-- TODO: just for the apple quest...needs to be deleted later on
yl_sokomine = {}
yl_sokomine["q_apple_explorer"] = {}
-- if player has npc_talk_owner priv AND is owner of this particular npc (second one: TODO):
--   chat option: "I am your owner. I have new orders for you.
--   -> enters edit mode
-- when edit_mode has been enabled, the following chat options are added to the options:
--   chat option: "Add new answer/option to this dialog."
--   -> adds a new option TODO
--   chat option: "That was all. I'm finished with giving you new orders. Remember them!"
--   -> ends edit mode
--
-- TODO: add the actual edit menu for options
-- can be entered from the edit, conditions and effects button;
-- style: Answer/Option: <text>
--        Lets the NPC answer with: <dialog_id> [Button GOTO target dialog]
--
--        Only offer this answer if all the following conditions are true:
--            <list of preconditions>
--        If at least one condition is not fulfilled, ..
--            <display the following text|grey out this answer|do not offer this answer>
--                <alternate answer>
--        When this answer has been selected, apply the following effects:
--            <list of effects>
--
--        [Store]  [Delete this option] [Back to dialog xyz] [GOTO target diaglog]
--
-- TODO: check if security is ok (minetest.formspec_escape etc)
-- TODO: actually process changed entries
-- TODO: allow owner to mute/unmute npc (would be bad if players can already see what is going
--       to happen while the owner creates a long quest)

--###
-- Init
--###

-- store if the player is editing a particular NPC; format: yl_speak_up.edit_mode[pname] = npc_id
yl_speak_up.edit_mode = {}

function yl_speak_up.init_mob_table()
    return false
end

minetest.register_on_leaveplayer(
    function(player)
        yl_speak_up.speak_to[player:get_player_name()] = nil
        yl_speak_up.edit_mode[player:get_player_name()] = nil
    end
)

minetest.register_on_joinplayer(
    function(player)
        yl_speak_up.speak_to[player:get_player_name()] = nil
        yl_speak_up.edit_mode[player:get_player_name()] = nil
    end
)

--###
-- Debug
--###

yl_speak_up.debug = true

local function say(text)
    if yl_speak_up.debug then
        --minetest.chat_send_all(text)
        minetest.log("action", "[MOD] yl_speak_up: " .. text)
    end
end

--###
-- Helpers
--###

local function get_prerequisite_types()
    --local t_gpt = {"item", "quest", "function", "auto", "delete"}
    local t_gpt = {"item", "function", "delete"}
    local s_gpt = ""
    for _, v in pairs(t_gpt) do
        s_gpt = s_gpt .. v .. ","
    end

    s_gpt = s_gpt:sub(1, -2) -- cut last comma

    return s_gpt, t_gpt
end

local function get_result_types()
    --local t_grt = {"dialog", "give_item", "quest", "function", "auto", "delete"}
    local t_grt = {"dialog","give_item","take_item","move","function","delete"}
    local s_grt = ""
    for _, v in pairs(t_grt) do
        s_grt = s_grt .. v .. ","
    end

    s_grt = s_grt:sub(1, -2) -- cut last comma

    return s_grt, t_grt
end

local function get_number_from_id(any_id)
    return string.split(any_id, "_")[2]
end

local function save_path(n_id)
    return yl_speak_up.worldpath .. yl_speak_up.path .. DIR_DELIM .. n_id .. ".json"
end

local function get_error_message()
    local formspec = {
        "formspec_version[3]",
        "size[13.4,8.5]",
        "bgcolor[#FF0000]",
        "label[0.2,0.35;Please save a NPC file first]",
        "button_exit[0.2,7.7;3,0.75;button_back;Back]"
    }

    return table.concat(formspec, "")
end

local function find_next_id(t)
    local start_id = 1

    if t == nil then
        return start_id
    end

    local keynum = 1
    for k, _ in pairs(t) do
        local keynum = tonumber(get_number_from_id(k))
        if keynum >= start_id then
            start_id = keynum + 1
        end
    end
    return start_id
end

local function sanitize_sort(options, value)
    local retval = value

    if value == "" or value == nil or tonumber(value) == nil then
        local temp = 0
        for k, v in pairs(options) do
            if v.o_sort ~= nil then
                if tonumber(v.o_sort) > temp then
                    temp = tonumber(v.o_sort)
                end
            end
        end
        retval = tostring(temp + 1)
    end
    return retval
end

--###
--Load and Save
--###

local function save_dialog(n_id, dialog)
    if type(n_id) ~= "string" or type(dialog) ~= "table" then
        return false
    end
    local p = save_path(n_id)
    local content = minetest.write_json(dialog)
    return minetest.safe_file_write(p, content)
end


local function load_dialog(n_id) -- returns the saved dialog
    local p = save_path(n_id)

    local file, err = io.open(p, "r")
    if err then
        return {}
    end
    io.input(file)
    local content = io.read()
    local dialog = minetest.parse_json(content)
    io.close(file)

    if type(dialog) ~= "table" then
        dialog = {}
    end

    return dialog
end

local function fields_to_dialog(pname, fields)
    local n_id = yl_speak_up.speak_to[pname].n_id
    local dialog = load_dialog(n_id)
    local save_d_id = ""

    if next(dialog) == nil then -- No file found. Let's create the basic values
        dialog = {}
        dialog.n_dialogs = {}
    end

    if dialog.n_dialogs == nil or next(dialog.n_dialogs) == nil then --No dialogs found. Let's make a table
        dialog.n_dialogs = {}
    end

    if fields.d_text ~= "" then -- If there is dialog text, then save new or old dialog
        if fields.d_id == yl_speak_up.text_new_dialog_id then --New dialog --
            -- Find highest d_id and increase by 1
            save_d_id = "d_" .. find_next_id(dialog.n_dialogs)

            -- Initialize empty dialog
            dialog.n_dialogs[save_d_id] = {}
        else -- Already existing dialog
            save_d_id = fields.d_id
        end
        -- Change dialog
        dialog.n_dialogs[save_d_id].d_id = save_d_id
        dialog.n_dialogs[save_d_id].d_type = "text"
        dialog.n_dialogs[save_d_id].d_text = fields.d_text
        dialog.n_dialogs[save_d_id].d_sort = fields.d_sort
    end

    --Context
    yl_speak_up.speak_to[pname].d_id = save_d_id

    -- Just in case the NPC vlaues where changed or set
    dialog.n_id = n_id
    dialog.n_description = fields.n_description
    dialog.n_npc = fields.n_npc

    return dialog
end

local function options_to_dialog(pname)
    local dialog = yl_speak_up.speak_to[pname].dialog

    local n_id = yl_speak_up.speak_to[pname].n_id
    local d_id = yl_speak_up.speak_to[pname].d_id
    local o_id = yl_speak_up.speak_to[pname].o_id
    local p_id = yl_speak_up.speak_to[pname].p_id
    local r_id = yl_speak_up.speak_to[pname].r_id

    if yl_speak_up.speak_to[pname].d_text then
        dialog.n_dialogs[d_id].d_text = yl_speak_up.speak_to[pname].d_text
    end

    --Find the o_id to save to
    local future_o_id = ""
    if yl_speak_up.speak_to[pname].o_id ~= nil and yl_speak_up.speak_to[pname].o_id ~= yl_speak_up.text_new_option_id then
        future_o_id = yl_speak_up.speak_to[pname].o_id
    else
        future_o_id = "o_" .. find_next_id(dialog.n_dialogs[d_id].d_options)

        if dialog.n_dialogs[d_id].d_options == nil then
            dialog.n_dialogs[d_id].d_options = {}
        end

        dialog.n_dialogs[d_id].d_options[future_o_id] = {}
    end

    --Find the p_id to save to
    local future_p_id = ""
    if
        yl_speak_up.speak_to[pname].p_id ~= nil and
            yl_speak_up.speak_to[pname].p_id ~= yl_speak_up.text_new_prerequisite_id
     then
        future_p_id = yl_speak_up.speak_to[pname].p_id
    else
        future_p_id = "p_" .. find_next_id(dialog.n_dialogs[d_id].d_options[future_o_id].o_prerequisites)
        if future_p_id == "p_1" then
            dialog.n_dialogs[d_id].d_options[future_o_id].o_prerequisites = {}
        end
        dialog.n_dialogs[d_id].d_options[future_o_id].o_prerequisites[future_p_id] = {}
    end

    --Find the r_id to save to
    local future_r_id = ""
    if yl_speak_up.speak_to[pname].r_id ~= nil and yl_speak_up.speak_to[pname].r_id ~= yl_speak_up.text_new_result_id then
        future_r_id = yl_speak_up.speak_to[pname].r_id
    else
        future_r_id = "r_" .. find_next_id(dialog.n_dialogs[d_id].d_options[future_o_id].o_results)
        if future_r_id == "r_1" then
            dialog.n_dialogs[d_id].d_options[future_o_id].o_results = {}
        end
        dialog.n_dialogs[d_id].d_options[future_o_id].o_results[future_r_id] = {}
    end

    --Edit options
    dialog.n_dialogs[d_id].d_options[future_o_id].o_id = future_o_id
    dialog.n_dialogs[d_id].d_options[future_o_id].o_hide_when_prerequisites_not_met =
        yl_speak_up.speak_to[pname].o_hide or "false"
    dialog.n_dialogs[d_id].d_options[future_o_id].o_grey_when_prerequisites_not_met =
        yl_speak_up.speak_to[pname].o_grey or "false"
    local s = sanitize_sort(dialog.n_dialogs[d_id].d_options, yl_speak_up.speak_to[pname].o_sort)
    dialog.n_dialogs[d_id].d_options[future_o_id].o_sort = s
    dialog.n_dialogs[d_id].d_options[future_o_id].o_text_when_prerequisites_not_met =
        yl_speak_up.speak_to[pname].o_not_met or ""
    dialog.n_dialogs[d_id].d_options[future_o_id].o_text_when_prerequisites_met =
        yl_speak_up.speak_to[pname].o_met or ""

    --Edit prerequisites

    --Do we delete the prerequisite?
    if
        yl_speak_up.speak_to[pname].p_type == "delete" and yl_speak_up.speak_to[pname].p_id ~= nil and
            yl_speak_up.speak_to[pname].p_id ~= yl_speak_up.text_new_prerequisite_id
     then
        dialog.n_dialogs[d_id].d_options[future_o_id].o_prerequisites[future_p_id] = nil
    else
        if yl_speak_up.speak_to[pname].p_value ~= nil and yl_speak_up.speak_to[pname].p_value ~= "" then
            dialog.n_dialogs[d_id].d_options[future_o_id].o_prerequisites[future_p_id].p_id = future_p_id
            dialog.n_dialogs[d_id].d_options[future_o_id].o_prerequisites[future_p_id].p_type =
                yl_speak_up.speak_to[pname].p_type
            dialog.n_dialogs[d_id].d_options[future_o_id].o_prerequisites[future_p_id].p_value =
                yl_speak_up.speak_to[pname].p_value
        end
    end

    --Do we delete the result?
    if
        yl_speak_up.speak_to[pname].r_type == "delete" and yl_speak_up.speak_to[pname].r_id ~= nil and
            yl_speak_up.speak_to[pname].r_id ~= yl_speak_up.text_new_result_id
     then
        dialog.n_dialogs[d_id].d_options[future_o_id].o_results[future_r_id] = nil
    else
        if yl_speak_up.speak_to[pname].r_value ~= nil and yl_speak_up.speak_to[pname].r_value ~= "" then
            dialog.n_dialogs[d_id].d_options[future_o_id].o_results[future_r_id].r_id = future_r_id
            dialog.n_dialogs[d_id].d_options[future_o_id].o_results[future_r_id].r_type =
                yl_speak_up.speak_to[pname].r_type
            dialog.n_dialogs[d_id].d_options[future_o_id].o_results[future_r_id].r_value =
                yl_speak_up.speak_to[pname].r_value
        end
    end

    return dialog
end

local function delete_dialog(n_id, d_id)
    if d_id == yl_speak_up.text_new_dialog_id then
        return false
    end -- We don't delete "New dialog"

    local dialog = load_dialog(n_id)

    dialog.n_dialogs[d_id] = nil

    save_dialog(n_id, dialog)
end

local function delete_option(n_id, d_id, o_id)
    if d_id == yl_speak_up.text_new_dialog_id then
        return false
    end -- We don't delete "New dialog" Also, something might have gone wrong here.
    if o_id == yl_speak_up.text_new_option_id then
        return false
    end -- We don't delete "New option"

    local dialog = load_dialog(n_id)

    dialog.n_dialogs[d_id].d_options[o_id] = nil

    save_dialog(n_id, dialog)
end

local function delete_prerequisite(n_id, d_id, o_id, p_id)
    if d_id == yl_speak_up.text_new_dialog_id then
        return false
    end -- We don't delete "New dialog" Also, something might have gone wrong here.
    if o_id == yl_speak_up.text_new_option_id then
        return false
    end -- We don't delete "New option" Also, something might have gone wrong here.
    if p_id == yl_speak_up.text_new_prerequisite_id then
        return false
    end

    local dialog = load_dialog(n_id)

    dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites[p_id] = nil

    save_dialog(n_id, dialog)
end

local function delete_result(n_id, d_id, o_id, r_id)
    if d_id == yl_speak_up.text_new_dialog_id then
        return false
    end -- We don't delete "New dialog" Also, something might have gone wrong here.
    if o_id == yl_speak_up.text_new_option_id then
        return false
    end -- We don't delete "New option" Also, something might have gone wrong here.
    if r_id == yl_speak_up.text_new_result_id then
        return false
    end

    local dialog = load_dialog(n_id)

    dialog.n_dialogs[d_id].d_options[o_id].o_resultss[r_id] = nil

    save_dialog(n_id, dialog)
end

local function calculate_displayable_options(pname, d_options)
    -- Let's go through all the options and see if we need to display them to the user

    local retval = {}

    local player = minetest.get_player_by_name(pname)

    if d_options == nil then
        return {}
    end

    for o_k, o_v in pairs(d_options) do
        --minetest.chat_send_all("#####"..o_k.."#####")
        local o_p_met = true
        if o_v.o_prerequisites == nil then
            --minetest.chat_send_all("display this because no prereq:"..dump(o_v))
        else
            --minetest.chat_send_all("prereqs exists")
            if next(o_v.o_prerequisites) == nil then
                --minetest.chat_send_all("prereqs exist, but empty")
            else
                --minetest.chat_send_all("prereqs exists and not empty")
                --minetest.chat_send_all("if all prereqs are met, then we can display the option")
                local p_met = {}
                for p_k, p_v in pairs(o_v.o_prerequisites) do
                    --minetest.chat_send_all("this is in a single prereq: "..dump(p_v))
                    p_met[p_k] = false
                    local p_id = p_v.p_id
                    if p_v.p_type == "item" then
                        --minetest.chat_send_all("item! Does the player have this thing?")
                        if player:get_inventory():contains_item("main", p_v.p_value) then
                            --minetest.chat_send_all("found item:"..p_v.p_value)
                            p_met[p_k] = true
                        end
                    end
                    if p_v.p_type == "quest" then
                        --minetest.chat_send_all("quest! let's call the quest api?")
                        p_met[p_k] = false
                    end
                    if p_v.p_type == "function" then
                        
                        local code = p_v.p_value
                        if code:byte(1) == 27 then
                            local obj = yl_speak_up.speak_to[pname].obj
                            local n_id = yl_speak_up.speak_to[pname].n_id
                            local npc = get_number_from_id(n_id)
                            if obj:get_luaentity() and tonumber(npc) then
                                minetest.log("error","[MOD] yl_speak_up: NPC with ID n_"..npc.." at position "..minetest.pos_to_string(obj:get_pos(),0).." could not compile the content of "..p_id.." :"..dump(code) .. " because of illegal bytecode for player "..pname)
                            else
                                minetest.log("error","[MOD] yl_speak_up: NPC with ID unknown could not compile the content of "..p_id.." :"..dump(code) .. " for player unknown because of illegal bytecode")
                            end
                        end
    
                        local f, msg = loadstring("return function(playername) " .. code .. " end")
    
                        if not f then
                            local obj = yl_speak_up.speak_to[pname].obj
                            local n_id = yl_speak_up.speak_to[pname].n_id
                            local npc = get_number_from_id(n_id)
                            if obj:get_luaentity() and tonumber(npc) then
                                minetest.log("error","[MOD] yl_speak_up: NPC with ID n_"..npc.." at position "..minetest.pos_to_string(obj:get_pos(),0).." could not compile the content of "..p_id.." :"..dump(code) .. " for player "..pname)
                            else
                                minetest.log("error","[MOD] yl_speak_up: NPC with ID unknown could not compile the content of "..p_id.." :"..dump(code) .. " for player unknown")
                            end
                        else
                        
    
                            local func = f()

                            local ok, ret = pcall(func,pname)
    
                            if not ok then
                                local obj = yl_speak_up.speak_to[pname].obj
                                local n_id = yl_speak_up.speak_to[pname].n_id
                                local npc = get_number_from_id(n_id)
                                if obj:get_luaentity() and tonumber(npc) then
                                    minetest.log("error","[MOD] yl_speak_up: NPC with ID n_"..npc.." at position "..minetest.pos_to_string(obj:get_pos(),0).." could not execute the content of "..p_id.." :"..dump(code) .. " for player "..pname)
                                else
                                    minetest.log("error","[MOD] yl_speak_up: NPC with ID unknown could not execute the content of "..p_id.." :"..dump(code) .. " for player unknown")
                                end
                            end

                            if type(ret) == "boolean" then
                                p_met[p_k] = ret
                            end

                        end
                        

                        
                    end
                    if p_v.p_type == "auto" then
                        --minetest.chat_send_all("auto! what shall we do now?")
                        p_met[p_k] = true
                    end
                end
                -- is there a "false" in the p_met ?
                for m_k, m_v in pairs(p_met) do
                    --minetest.chat_send_all(o_k..",m_v="..dump(m_v))
                    if m_v == false then
                        o_p_met = false
                    end
                end
            end
        end
        -- Can we display this option?
        retval[o_k] = o_p_met
        --[[
            if o_p_met == true then
                minetest.chat_send_all("Prereqs say YES")
                retval[o_k] = o_p_met
            else
                minetest.chat_send_all("Prereqs say NOO")
            end
            ]]--
    end
    return retval
end

local function calculate_portrait(pname, n_id)
    local tex = yl_speak_up.speak_to[pname].textures

    local head = ""

    head = head .. "[combine:8x8:-8,-8=" .. tex[2] .. ":-40,-8=" .. tex[2]

    return head
end

--###
--Formspecs
--###

-- get formspecs

-- dialog

local function get_fs_setdialog(clicker, n_id, d_id)
    local dialog = load_dialog(n_id)

    local items = yl_speak_up.text_new_dialog_id
    local count = 1
    local d_sort = ""
    local text = ""

    if next(dialog) == nil then -- file does not exist
        dialog.n_id = n_id
        dialog.n_npc = ""
        dialog.n_description = ""
    elseif dialog.n_dialogs == nil then -- file does exist, but no dialogs are set
        dialog.n_id = n_id
        text = ""
    else -- file exists and there's already content
        local n = 1
        for k, v in pairs(dialog.n_dialogs) do
            n = n + 1
            if k == d_id then
                count = n
                d_sort = v.d_sort or ""
                text = v.d_text or ""
            end
            items = items .. "," .. v.d_id
        end

        text = minetest.formspec_escape(text)
    end

    local formspec = {
        "formspec_version[3]",
        "size[13.4,8.5]",
        "label[0.2,0.35;",
        dialog.n_id,
        "]",
        "field[1,0.1;4,0.5;n_npc;;",
        dialog.n_npc,
        "]",
        "field[5.2,0.1;8,0.5;n_description;;",
        dialog.n_description,
        "]",
        "dropdown[5.2,0.75;5,0.75;d_id;",
        items,
        ";",
        count,
        "]",
        "label[0.2,1;Sort]",
        "field[1.0,0.75;4,0.5;d_sort;;",
        d_sort,
        "]",
        "textarea[0.2,1.6;13,6;d_text;;",
        text,
        "]",
        "button_exit[0.2,7.7;3,0.75;button_cancel;Cancel]",
        "button[4,7.7;3,0.75;button_delete;Delete]",
        "button[7.1,7.7;3,0.75;button_option;Options]",
        "button[10.2,7.7;3,0.75;button_save;Save]",
        -- tooltips

        "tooltip[n_npc;n_npc: The name of the NPC;#FFFFFF;#000000]",
        "tooltip[n_description;n_description: A description for the NPC;#FFFFFF;#000000]",
        "tooltip[d_sort;d_sort: Make this 0 on your dialog if you want it to be shown the first time a player talks to the NPC\nNegative values are ignored\n;#FFFFFF;#000000]",
        "tooltip[5.2,0.75;5,0.75;d_id: Dialog Id;#FFFFFF;#000000]",
        "tooltip[d_text;d_text: Dialog text. What the NPC says to you;#FFFFFF;#000000]"
    }

    return table.concat(formspec, "")
end

-- options

local function get_fs_optiondialog(player, n_id, d_id, o_id, p_id, r_id)
    local dialog = load_dialog(n_id)
    local pname = player:get_player_name()

    if next(dialog) == nil or d_id == yl_speak_up.text_new_dialog_id or dialog.n_dialogs == nil then -- file does not exist or the user sent the New dialog
        return get_error_message(n_id)
    end

    -- default values
    local out = {}

    -- npc
    out.n_id = n_id

    -- dialog
    out.d_id = yl_speak_up.text_new_dialog_id
    out.d_text = "Dialog Text"

    -- option
    out.o_id_items = yl_speak_up.text_new_option_id
    out.o_id_count = 1
    out.o_hide = "false"
    out.o_grey = "false"
    out.o_sort = ""
    out.o_met = "Text when conditions are met"
    out.o_not_met = "Text when conditions are not met"

    -- prerequisite
    out.p_id_items = yl_speak_up.text_new_prerequisite_id
    out.p_id_count = 1
    out.p_type_items, out.p_type_items_table = get_prerequisite_types()
    out.p_type_count = 1
    out.p_value = ""

    -- result
    out.r_id_items = yl_speak_up.text_new_result_id
    out.r_id_count = 1
    out.r_type_items = get_result_types()
    out.r_type_count = 1
    out.r_value = ""

    --dialogs
    for k, v in pairs(dialog.n_dialogs) do
        if k == d_id then
            out.d_id = v.d_id
            out.d_text = minetest.formspec_escape(v.d_text):trim()
        end
    end

    --options
    if dialog.n_dialogs[d_id].d_options ~= nil then
        local o_n = 1
        for o_k, o_v in pairs(dialog.n_dialogs[d_id].d_options) do
            o_n = o_n + 1
            if o_k == o_id then
                out.o_id_count = o_n
            end
            out.o_id_items = out.o_id_items .. "," .. o_v.o_id
        end
        if dialog.n_dialogs[d_id].d_options[o_id] then
            if dialog.n_dialogs[d_id].d_options[o_id].o_hide_when_prerequisites_not_met then
                out.o_hide = dialog.n_dialogs[d_id].d_options[o_id].o_hide_when_prerequisites_not_met
            end
            if dialog.n_dialogs[d_id].d_options[o_id].o_grey_when_prerequisites_not_met then
                out.o_grey = dialog.n_dialogs[d_id].d_options[o_id].o_grey_when_prerequisites_not_met
            end
            if dialog.n_dialogs[d_id].d_options[o_id].o_sort then
                out.o_sort = dialog.n_dialogs[d_id].d_options[o_id].o_sort
            end
            if dialog.n_dialogs[d_id].d_options[o_id].o_text_when_prerequisites_met then
                out.o_met =
                    minetest.formspec_escape(dialog.n_dialogs[d_id].d_options[o_id].o_text_when_prerequisites_met):trim(

                )
            end
            if dialog.n_dialogs[d_id].d_options[o_id].o_text_when_prerequisites_not_met then
                out.o_not_met =
                    minetest.formspec_escape(dialog.n_dialogs[d_id].d_options[o_id].o_text_when_prerequisites_not_met):trim(

                )
            end

            -- prerequisite

            --if dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites ~= nil and p_id == yl_speak_up.text_new_prerequisite_id then -- new prerequisite
            --end
            if dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites ~= nil then
                local p_n = 1
                for p_k, p_v in pairs(dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites) do
                    p_n = p_n + 1
                    if p_k == p_id then
                        out.p_id_count = p_n
                    end
                    out.p_id_items = out.p_id_items .. "," .. p_v.p_id
                end

                out.p_type_items, out.p_type_items_table = get_prerequisite_types()

                if
                    dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites[p_id] ~= nil and
                        dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites[p_id].p_type ~= nil
                 then
                    local p_type_n = 1
                    for _, p_type_v in pairs(out.p_type_items_table) do
                        if p_type_v == dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites[p_id].p_type then
                            out.p_type_count = p_type_n
                        end
                        p_type_n = p_type_n + 1
                    end

                    out.p_value =
                        minetest.formspec_escape(dialog.n_dialogs[d_id].d_options[o_id].o_prerequisites[p_id].p_value):trim(

                    )
                end
            end

            -- result
            if dialog.n_dialogs[d_id].d_options[o_id].o_results ~= nil then
                local r_n = 1
                for r_k, r_v in pairs(dialog.n_dialogs[d_id].d_options[o_id].o_results) do
                    r_n = r_n + 1
                    if r_k == r_id then
                        out.r_id_count = r_n
                    end
                    out.r_id_items = out.r_id_items .. "," .. r_v.r_id
                end

                out.r_type_items, out.r_type_items_table = get_result_types()

                if
                    dialog.n_dialogs[d_id].d_options[o_id].o_results[r_id] ~= nil and
                        dialog.n_dialogs[d_id].d_options[o_id].o_results[r_id].r_type ~= nil
                 then
                    local r_type_n = 1
                    for _, r_type_v in pairs(out.r_type_items_table) do
                        if r_type_v == dialog.n_dialogs[d_id].d_options[o_id].o_results[r_id].r_type then
                            out.r_type_count = r_type_n
                        end
                        r_type_n = r_type_n + 1
                    end

                    out.r_value =
                        minetest.formspec_escape(dialog.n_dialogs[d_id].d_options[o_id].o_results[r_id].r_value):trim()
                end
            end
        end
    end

    local formspec = {
        "formspec_version[3]",
        "size[13.4,8.5]",
        -- npc
        "field[-10,-10;4,0.5;n_id;;",
        out.n_id,
        "]",
        -- dialog
        "field[-10,-10;4,0.5;d_id;;",
        out.d_id,
        "]",
        "label[0.2,0.35;",
        out.d_id,
        "]",
        "field[1,0.1;12.2,0.5;d_text;;",
        out.d_text,
        "]",
        -- option
        "dropdown[0.2,0.75;2,0.75;o_id;",
        out.o_id_items,
        ";",
        out.o_id_count,
        "]",
        "checkbox[0.2,1.85;o_hide;Hide;",
        out.o_hide,
        "]",
        "checkbox[0.2,2.35;o_grey;Grey;",
        out.o_grey,
        "]",
        "field[1.6,2.05;0.75,0.5;o_sort;Sort;",
        out.o_sort,
        "]",
        "textarea[2.4,0.75;10.8,0.95;o_met;;",
        out.o_met,
        "]",
        "textarea[2.4,1.75;10.8,0.95;o_not_met;;",
        out.o_not_met,
        "]",
        -- prerequisite
        "dropdown[0.2,2.8;3,0.75;p_id;",
        out.p_id_items,
        ";",
        out.p_id_count,
        "]",
        "dropdown[0.2,3.8;3,0.75;p_type;",
        out.p_type_items,
        ";",
        out.p_type_count,
        "]",
        "textarea[3.4,2.8;9.8,2.1;p_value;;",
        out.p_value,
        "]",
        -- result
        "dropdown[0.2,5;3,0.75;r_id;",
        out.r_id_items,
        ";",
        out.r_id_count,
        "]",
        "dropdown[0.2,6;3,0.75;r_type;",
        out.r_type_items,
        ";",
        out.r_type_count,
        "]",
        "textarea[3.4,5;9.8,2.1;r_value;;",
        out.r_value,
        "]",
        -- buttons
        "button[0.2,7.7;3,0.75;button_back;Back]",
        "button[7.1,7.7;3,0.75;button_delete;Delete OPTION]",
        "button[10.2,7.7;3,0.75;button_save;Save]",
        -- tooltips

        "tooltip[d_text;d_text: Dialog text. What the NPC says to you\n\n",
        out.d_text,
        ";#FFFFFF;#000000]",
        "tooltip[0.2,0.75;2,0.75;o_id: Option Id;#FFFFFF;#000000]",
        "tooltip[o_met;o_met: Option text when prerequisites are met\n(What you say to the NPC)\n\n",
        out.o_met,
        ";#FFFFFF;#000000]",
        "tooltip[o_not_met;o_not_met: Option text when prerequisites are not met\n(What you say to the NPC instead)\n\n",
        out.o_not_met,
        ";#FFFFFF;#000000]",
        "tooltip[o_hide;o_hide: If checked, this option is hidden when prerequistes are not met;#FFFFFF;#000000]",
        "tooltip[o_grey;o_grey: If checked, this option is shown when prerequistes are not met, but grey and not selectable;#FFFFFF;#000000]",
        "tooltip[o_sort;o_sort: The lower the number, the higher up in the list this option goes\nNegative values are ignored;#FFFFFF;#000000]",
        "tooltip[0.2,2.8;3,0.75;p_id: Prerequisite Id;#FFFFFF;#000000]",
        "tooltip[0.2,3.8;3,0.75;p_type: Defines what the p_value stands for.\n\n",
        "item: requires the user to have this item in the inventory\n",
        "quest: requires the user to have completed a quest with this id\n",
        "function: executes the given LUA function which must return true or false. true = prerequisite met\n",
        "auto: ???\n",
        "delete: Deletes the chosen prerequiste when the dialog is saved",
        ";#FFFFFF;#000000]",
        "tooltip[p_value;p_value: This is evaluated to decide whether the prerequisites are met or not;#FFFFFF;#000000]",
        "tooltip[0.2,5;3,0.75;r_id: Result Id;#FFFFFF;#000000]",
        "tooltip[0.2,6;3,0.75;r_type: Defines what the r_value stands for.\n\n",
        "dialog: forwards the user to the given dialog d_id\n",
        "item: places this item in the inventory of the user\n",
        "quest: starts a quest with this id for the user\n",
        "function: executes the given LUA function\n",
        "auto: automatically forwards the user to the given dialog d_id after a given time\n",
        "delete: Deletes the chosen prerequiste when the dialog is saved",
        ";#FFFFFF;#000000]",
        "tooltip[r_value;r_value: This is what happens when the user chooses this option;#FFFFFF;#000000]"
    }

    return table.concat(formspec, "")
end

-- talk

local function get_fs_talkdialog(player, n_id, d_id)
    local pname = player:get_player_name()
    local dialog = yl_speak_up.speak_to[pname].dialog
    local context_d_id = yl_speak_up.speak_to[pname].d_id
    local active_dialog

    if not player and not player:is_player() then
        minetest.log(
            "action",
            "[MOD] yl_speak_up: User " ..
                pname ..
                    " talked to unconfigured NPC with ID n_" ..
                        n_id .. ", position of user was " .. minetest.pos_to_string(player:get_pos(), 0)
        )
        return get_error_message()
    end

    --[[ If we have an explicit call for a certain d_id, we grab it from parameters. 
    If not, we grab in from context. 
    When neither are present, we grab it from d_sort
    ]]--
    
    local c_d_id

    if d_id ~= nil then
        active_dialog = dialog.n_dialogs[d_id]
        c_d_id = d_id
    elseif yl_speak_up.speak_to[pname].d_id ~= nil then
        c_d_id = yl_speak_up.speak_to[pname].d_id
        active_dialog = dialog.n_dialogs[c_d_id]
    elseif dialog.n_dialogs ~= nil then
        -- Find the dialog with d_sort = 0
        local lowest_sort = nil
        for k, v in pairs(dialog.n_dialogs) do
            if tonumber(v.d_sort) ~= nil then
                if not lowest_sort or tonumber(v.d_sort) < tonumber(lowest_sort) or v.d_sort == "0" then
                    if tonumber(v.d_sort) >= 0 then
                        lowest_sort = v.d_sort
                        active_dialog = v
                        c_d_id = k
                    end
                end
            end
        end
    else
        minetest.log(
            "action",
            "[MOD] yl_speak_up: User " ..
                pname ..
                    " talked to unconfigured NPC with ID n_" ..
                        n_id .. ", position of user was " .. minetest.pos_to_string(player:get_pos(), 0)
        )
        return get_error_message()
    end

    if c_d_id == nil then return get_error_message() end

    yl_speak_up.speak_to[pname].d_id = c_d_id

    -- Now we have a dialog to display to the user

    local allowed = calculate_displayable_options(pname, active_dialog.d_options)
    yl_speak_up.speak_to[pname].allowed = allowed

    local portrait = calculate_portrait(pname, n_id)

    local formspec_v = minetest.get_player_information(pname).formspec_version
    local protocol_v = minetest.get_player_information(pname).protocol_version
    local formspec = {}
    local h

    if formspec_v >= 4 then
        formspec = {
            "formspec_version[3]",
            "size[57,33]",
            "position[0,0.45]",
            "anchor[0,0.45]",
            "no_prepend[]",
            "bgcolor[#00000000;false]",
            -- Container

            "container[2,0.75]",
            -- Background

            "background[0,0;20,23;yl_speak_up_bg_dialog.png;false]",
            "background[0,24;54.5,7.5;yl_speak_up_bg_dialog.png;false]",
            -- Frame Dialog

            "image[-0.25,-0.25;1,1;yl_speak_up_bg_dialog_tl.png]",
            "image[-0.25,22.25;1,1;yl_speak_up_bg_dialog_bl.png]",
            "image[19.25,-0.25;1,1;yl_speak_up_bg_dialog_tr.png]",
            "image[19.25,22.25;1,1;yl_speak_up_bg_dialog_br.png]",
            "image[-0.25,0.75;1,21.5;yl_speak_up_bg_dialog_hl.png]",
            "image[19.25,0.75;1,21.5;yl_speak_up_bg_dialog_hr.png]",
            "image[0.75,-0.25;18.5,1;yl_speak_up_bg_dialog_vt.png]",
            "image[0.75,22.25;18.5,1;yl_speak_up_bg_dialog_vb.png]",
            -- Frame Options

            "image[-0.25,23.75;1,1;yl_speak_up_bg_dialog_tl.png]",
            "image[-0.25,30.75;1,1;yl_speak_up_bg_dialog_bl.png]",
            "image[53.75,23.75;1,1;yl_speak_up_bg_dialog_tr.png]",
            "image[53.75,30.75;1,1;yl_speak_up_bg_dialog_br.png]",
            "image[-0.25,24.75;1,6;yl_speak_up_bg_dialog_hl.png]",
            "image[53.75,24.75;1,6;yl_speak_up_bg_dialog_hr.png]",
            "image[0.75,23.75;53,1;yl_speak_up_bg_dialog_vt.png]",
            "image[0.75,30.75;53,1;yl_speak_up_bg_dialog_vb.png]",
            "style_type[button;bgcolor=#a37e45]",
            "style_type[button_exit;bgcolor=#a37e45]", -- Dialog

            --[[
            "background[-1,-1;22,25;yl_speak_up_bg_dialog2.png;false]",
            "background[-1,23;58,10;yl_speak_up_bg_dialog2.png;false]",
            "style_type[button;bgcolor=#a37e45]",
            ]]-- 
            "label[0.3,0.6;",
            minetest.formspec_escape(dialog.n_npc),
            "]",
            "label[0.3,1.8;",
            minetest.formspec_escape(dialog.n_description),
            "]",
            "image[15.5,0.5;4,4;",
            portrait,
            "]",
        }

	-- Is the player working on this particular npc?
	local edit_mode = (yl_speak_up.edit_mode[pname] == yl_speak_up.speak_to[pname].n_id)

	-- this is used to build a list of all available dialogs for a dropdown menu in edit mode
	-- (only relevant in edit mode)
        local dialog_list = yl_speak_up.text_new_dialog_id
	-- find the right index for the dialog_list dropdown above
	local d_id_to_dropdown_index = {}

	-- display the window with the text the NPC is saying
	-- TODO: make name and description likewise editable?
	if(edit_mode) then

	    -- TODO: sort by name?
            -- build the list of available dialogs for the dropdown list(s)
            -- if there are dialogs defined
            if(dialog and dialog.n_dialogs) then
                -- the first entry will be "New dialog"
                local n = 1
                for k, v in pairs(dialog.n_dialogs) do
                    dialog_list = dialog_list .. "," .. v.d_id
		    -- which one is the current dialog?
                    n = n + 1
		    d_id_to_dropdown_index[v.d_id] = n
                end
            end

	    local i = (d_id_to_dropdown_index[c_d_id] or 0)
            table.insert(formspec, "label[0.2,4.6;Dialog:]") -- "..minetest.formspec_escape(c_d_id)..":]")
	    table.insert(formspec, "dropdown[3.0,4.0;5,1;d_id;"..dialog_list..";"..i..",]")
            table.insert(formspec, "tooltip[3.0,4.0;5,1;Select the dialog you want to edit. Currently, dialog "..c_d_id.." is beeing displayed.;#FFFFFF;#000000]")
	    -- add previous/next buttons for previous/next dialog (sorted as in the dropdown menu);
	    -- this is just an alternate way of walking through the dialogs
	    for k,v in pairs(d_id_to_dropdown_index) do
                if(    v == i-1) then
                    table.insert(formspec, "button[8.5,4.0;2,0.9;prev_dialog_"..k..";<]")
		    -- add a tooltip
                    table.insert(formspec, "tooltip[prev_dialog_" .. k .. ";Go to previous dialog "..k..".]")
                elseif(v == i+1) then
                    table.insert(formspec, "button[11,4.0;2,0.9;next_dialog_"..k..";>]")
		    -- add a tooltip
                    table.insert(formspec, "tooltip[next_dialog_" .. k .. ";Go to next dialog "..k..".]")
                end
            end
            -- add a "+" button for creating a new dialog
            table.insert(formspec, "button[13.9,4.0;1,0.9;show_new_dialog;+]")
            table.insert(formspec, "tooltip[show_new_dialog;Create a new dialog.]")


            table.insert(formspec, "textarea[0.2,5;19.6,17.8;d_text;;")
            table.insert(formspec, minetest.formspec_escape(active_dialog.d_text))
            table.insert(formspec, "]")
	else
            table.insert(formspec, "hypertext[0.2,5;19.6,17.8;d_text;<normal>")
            table.insert(formspec, minetest.formspec_escape(active_dialog.d_text) .. "\n</normal>")
            table.insert(formspec, "]")
            table.insert(formspec, "tooltip[d_text;")
            table.insert(formspec, minetest.formspec_escape(active_dialog.d_text):trim())
            table.insert(formspec, ";#000000;#FFFFFF]")
        end
        table.insert(formspec, "scrollbaroptions[min=0;max=14;smallstep=1;largestep=2;arrows=show]")
        table.insert(formspec, "scrollbar[0.2,24.2;0.2,7;vertical;scr0;0]")
        table.insert(formspec, "scroll_container[0,24;56,7;scr0;vertical;1]")
        h = -0.8

        -- Let#s sort the options by o_sort
        if active_dialog ~= nil and active_dialog.d_options ~= nil then
            local sorted_buttons = {}
            for _, ad_v in pairs(active_dialog.d_options) do
                sorted_buttons[tonumber(ad_v.o_sort)] = ad_v
            end

            for _, sb_v in pairs(sorted_buttons) do
                -- in edit_mode: show all options
		if edit_mode then
                    h = h + 1
		    -- add a button "o_<nr>:" that leads to an edit formspec for this option
                    table.insert(formspec, "button[1.8," .. h .. ";2,0.9;edit_option_" .. sb_v.o_id .. ";"..sb_v.o_id..":]")
		    -- add a tooltip "Edit target dialog, pre(C)onditions and (E)ffects for option o_<nr>"
                    table.insert(formspec, "tooltip[edit_option_" .. sb_v.o_id .. ";Edit target dialog, pre(C)onditions and (E)ffects for option "..sb_v.o_id..".]")

                    -- find the right target dialog for this option (if it exists):
		    local target_dialog = nil
                    local results = active_dialog.d_options[sb_v.o_id].o_results
		    -- has this option more results/effects than just switching to another dialog?
		    local has_other_results = false
		    if(results ~= nil) then
                        for k, v in pairs(results) do
                            if v.r_type == "dialog" and dialog.n_dialogs[v.r_value] ~= nil then
			        -- there may be more than one in the data structure
                                target_dialog = v.r_value
                            elseif v.r_type ~= "dialog" then
                                has_other_results = true
                            end
                        end
                    end
		    if(target_dialog) then
		        -- add a button "-> d_<nr>" that leads to the target dialog (if one is set)
                        table.insert(formspec, "button[8.5," .. h .. ";1,0.9;button_" .. sb_v.o_id .. ";->]")
		        -- add a tooltip "Go to target dialog d_<nr>"
                        table.insert(formspec, "tooltip[button_" .. sb_v.o_id .. ";Go to target dialog "..target_dialog.." that will be shown when this option ("..sb_v.o_id..") is selected.]")

			-- selecting an option this way MUST NOT execute the pre(C)onditions or (E)ffects!
		    end
		    -- allow to set a new target dialog
	            table.insert(formspec, "dropdown[3.9,"..h..";4.7,1;d_id_"..sb_v.o_id..";"..dialog_list..";"..(d_id_to_dropdown_index[target_dialog] or "0")..",]")
		    -- add a tooltip "Change target dialog"
                    table.insert(formspec, "tooltip[3.9,"..h..";4.7,1;Change target dialog for option "..sb_v.o_id..".;#FFFFFF;#000000]")

		    -- are there any prerequirements?
                    local prereq = active_dialog.d_options[sb_v.o_id].o_prerequisites
		    if(prereq) then
                        table.insert(formspec, "button[0.5," .. h .. ";0.5,0.9;conditions_"..sb_v.o_id..";C]")
		        -- label: "There are pre(C)onditions required for showing this option. Display them."
                        table.insert(formspec, "tooltip[conditions_" .. sb_v.o_id .. ";There are pre(C)onditions required for showing this option. Display them.]")
                    end
		    if(has_other_results) then
                        table.insert(formspec, "button[1.1," .. h .. ";0.6,0.9;effects_"..sb_v.o_id..";Ef]")
		        -- label: "There are further (E)ffects (apart from switching to a new dialog) set for this option. Display them."
                        table.insert(formspec, "tooltip[effects_" .. sb_v.o_id .. ";There are further (E)ffects (apart from switching to a new dialog) set for this option. Display them.]")
                    end

		    -- show the actual text for the option
                    table.insert(formspec, "field[9.4," .. h .. ";44.9,0.9;text_option_" .. sb_v.o_id .. ";;"..sb_v.o_text_when_prerequisites_met.."]")
		    -- add a tooltip "Edit the text that is displayed on button o_<nr>."
                    table.insert(formspec, "tooltip[text_option_" .. sb_v.o_id .. ";Edit the text that is displayed on button "..sb_v.o_id..".]")

		-- normal mode: show an option if the prerequirements (if any are defined) are met
	        elseif allowed[sb_v.o_id] == true then
                    h = h + 1
                    table.insert(formspec, "button[0.5," .. h .. ";53.8,0.9;button_" .. sb_v.o_id .. ";]")
                    table.insert(
                        formspec,
                        "tooltip[button_" .. sb_v.o_id .. ";" .. sb_v.o_text_when_prerequisites_met .. "]"
                    )
                    local l = h + 0.45
                    table.insert(formspec, "label[0.7," .. l .. ";" .. sb_v.o_text_when_prerequisites_met .. "]")
                else
                    if sb_v.o_hide_when_prerequisites_not_met == "true" then
                    else
                        if
                            sb_v.o_grey_when_prerequisites_not_met == "true" and
                                sb_v.o_text_when_prerequisites_not_met == ""
                         then
                            h = h + 1
                            table.insert(formspec, "button[0.5," .. h .. ";53.8,0.9;button_" .. sb_v.o_id .. ";]")
                            table.insert(
                                formspec,
                                "tooltip[button_" ..
                                    sb_v.o_id ..
                                        ";" .. yl_speak_up.message_button_option_prerequisites_not_met_default .. "]"
                            )
                            local l = h + 0.45
                            table.insert(
                                formspec,
                                "label[0.7," ..
                                    l .. ";" .. yl_speak_up.message_button_option_prerequisites_not_met_default .. "]"
                            )
                            table.insert(formspec, "box[0.5," .. h .. ";53.8,0.9;#BBBBBB]")
                        end
                        if
                            sb_v.o_grey_when_prerequisites_not_met == "true" and
                                sb_v.o_text_when_prerequisites_not_met ~= ""
                         then
                            h = h + 1
                            table.insert(formspec, "button[0.5," .. h .. ";53.8,0.9;button_" .. sb_v.o_id .. ";]")
                            table.insert(
                                formspec,
                                "tooltip[button_" .. sb_v.o_id .. ";" .. sb_v.o_text_when_prerequisites_not_met .. "]"
                            )
                            local l = h + 0.45
                            table.insert(
                                formspec,
                                "label[0.7," .. l .. ";" .. sb_v.o_text_when_prerequisites_not_met .. "]"
                            )
                            table.insert(formspec, "box[0.5," .. h .. ";53.8,0.9;#BBBBBB]")
                        end
                        if
                            sb_v.o_grey_when_prerequisites_not_met == "false" and
                                sb_v.o_text_when_prerequisites_not_met == ""
                         then
                        -- no hide, no grey, no text
                        end
                        if
                            sb_v.o_grey_when_prerequisites_not_met == "false" and
                                sb_v.o_text_when_prerequisites_not_met ~= ""
                         then
                            -- no grey, but text
                            h = h + 1
                            table.insert(formspec, "button[0.5," .. h .. ";53.8,0.9;button_" .. sb_v.o_id .. ";]")
                            table.insert(
                                formspec,
                                "tooltip[button_" .. sb_v.o_id .. ";" .. sb_v.o_text_when_prerequisites_not_met .. "]"
                            )
                            local l = h + 0.45
                            table.insert(
                                formspec,
                                "label[0.7," .. l .. ";" .. sb_v.o_text_when_prerequisites_not_met .. "]"
                            )
                        end
                    end
                end
            end
        end

	-- If in edit mode, add two new menu entries: "add new options" and "end edit mode".
	if(edit_mode) then
            -- chat option: "Add a new answer/option to this dialog."
            h = h + 1
            table.insert(formspec, "button_exit[0.5," .. h .. ";53.8,0.9;button_add_option;]")
            table.insert(formspec, "tooltip[button_add_option;Adds a new option to this dialog. You can delete options via the option edit menu.]")
            table.insert(formspec, "label[0.7,"..(h+0.45)..";Add a new option/answer to this dialog. You can delete options via the option edit menu.]")
            -- chat option: "That was all. I'm finished with giving you new orders. Remember them!"
            h = h + 1
            table.insert(formspec, "button_exit[0.5," .. h .. ";53.8,0.9;button_end_edit_mode;]")
            table.insert(formspec, "tooltip[button_end_edit_mode;Ends edit mode. From now on, your NPC will talk to you like he talks to other players. You can always give him new orders by entering edit mode again.]")
            table.insert(formspec, "label[0.7,"..(h+0.45)..";That was all. I'm finished with giving you new orders. Remember them!]")

        -- Offer to enter edit mode if the player has the npc_talk_owner priv AND owns the npc.
	-- The npc_master priv allows to edit all NPC.
	-- TODO: the player also has to be owner of that particular npc
        elseif((minetest.check_player_privs(player, {npc_talk_owner=true}))
            or (minetest.check_player_privs(player, {npc_master=true}))) then
            -- chat option: "I am your owner. I have new orders for you.
            h = h + 1
            table.insert(formspec, "button_exit[0.5," .. h .. ";53.8,0.9;button_start_edit_mode;]")
            table.insert(formspec, "tooltip[button_start_edit_mode;Enters edit mode. In this mode, you can edit the texts the NPC says and the answers that can be given.]")
            table.insert(formspec, "label[0.7,"..(h+0.45)..";I am your owner. I have new orders for you.]")
        end

        h = h + 1
        table.insert(formspec, "button_exit[0.5," .. h .. ";53.8,0.9;button_exit;]")
        table.insert(formspec, "tooltip[button_exit;" .. yl_speak_up.message_button_option_exit .. "]")
        local l = h + 0.45
        table.insert(formspec, "label[0.7," .. l .. ";" .. yl_speak_up.message_button_option_exit .. "]")

        table.insert(formspec, "scroll_container_end[]")

        table.insert(formspec, "container_end[]")
    else
        minetest.log(
            "info",
            "[MOD] yl_speak_up: User " .. pname .. " talked to NPC ID n_" .. n_id .. " with an old formspec version!"
        )

        local upgrade_warning = ""
        local max_number_of_buttons = yl_speak_up.max_number_of_buttons
        local start_index = yl_speak_up.speak_to[pname].option_index

        if formspec_v < 3 or protocol_v < 39 then
            local warn = {
                "box[0.3,3;15,2;red]",
                "label[0.7,3.2;",
                yl_speak_up.text_version_warning,
                "]"
            }
            upgrade_warning = table.concat(warn, "")
        end

        formspec = {
            "formspec_version[1]",
            "size[48,28]",
            "position[0,0.45]",
            "anchor[0,0.45]",
            "no_prepend[]",
            "bgcolor[#00000000;false]",
            -- Container

            "container[2,0.75]",
            -- Background

            "background[0,0;20,17;yl_speak_up_bg_dialog.png]",
            "background[0,18;45,8;yl_speak_up_bg_dialog.png]",
            -- Frame Dialog

            "image[-0.35,-0.35;1,1;yl_speak_up_bg_dialog_tl.png]",
            "image[-0.35,16.25;1,1;yl_speak_up_bg_dialog_bl.png]",
            "image[19.35,-0.35;1,1;yl_speak_up_bg_dialog_tr.png]",
            "image[19.35,16.25;1,1;yl_speak_up_bg_dialog_br.png]",
            "image[-0.35,0.35;1,19.5;yl_speak_up_bg_dialog_hl.png]",
            "image[19.35,0.35;1,19.5;yl_speak_up_bg_dialog_hr.png]",
            "image[0.35,-0.35;24.5,1;yl_speak_up_bg_dialog_vt.png]",
            "image[0.35,16.25;24.5,1;yl_speak_up_bg_dialog_vb.png]",
            -- Frame Options

            "image[-0.35,17.65;1,1;yl_speak_up_bg_dialog_tl.png]",
            "image[-0.35,25.35;1,1;yl_speak_up_bg_dialog_bl.png]",
            "image[44.35,17.65;1,1;yl_speak_up_bg_dialog_tr.png]",
            "image[44.35,25.35;1,1;yl_speak_up_bg_dialog_br.png]",
            "image[-0.35,18.35;1,8.5;yl_speak_up_bg_dialog_hl.png]",
            "image[44.35,18.35;1,8.5;yl_speak_up_bg_dialog_hr.png]",
            "image[0.35,17.65;56.5,1;yl_speak_up_bg_dialog_vt.png]",
            "image[0.35,25.35;56.5,1;yl_speak_up_bg_dialog_vb.png]",
            -- Upgrade Warning

            upgrade_warning,
            -- Dialog

            "label[0.3,0.6;",
            minetest.formspec_escape(dialog.n_npc),
            "]",
            "label[0.3,1.8;",
            minetest.formspec_escape(dialog.n_description),
            "]",
            "image[15.5,0.5;4,4;",
            portrait,
            "]",
            "textarea[0.5,5;19.6,13.5;;;",
            minetest.formspec_escape(active_dialog.d_text) .. "\n",
            "]",
            "container[0,18]"
        }
        h = -1

        if active_dialog ~= nil and active_dialog.d_options ~= nil then
            -- Let's sort the options by o_sort.
            local sorted_buttons = {}
            for _, ad_v in pairs(active_dialog.d_options) do
                sorted_buttons[tonumber(ad_v.o_sort)] = ad_v
            end

            if #sorted_buttons > max_number_of_buttons then
                -- Generate arrows
                table.insert(formspec, "button[0.1,0;1,0.9;button_down;^]")
                table.insert(formspec, "button[0.1,7.0;1,0.9;button_up;v]")
            end

            local counter = 1

            for _, sb_v in pairs(sorted_buttons) do
                local end_index = start_index + max_number_of_buttons
                if counter >= start_index and counter < end_index then
                    if allowed[sb_v.o_id] == true then
                        h = h + 1
                        table.insert(
                            formspec,
                            "button[1," ..
                                h .. ";44,0.9;button_" .. sb_v.o_id .. ";" .. sb_v.o_text_when_prerequisites_met .. "]"
                        )
                        table.insert(
                            formspec,
                            "tooltip[button_" .. sb_v.o_id .. ";" .. sb_v.o_text_when_prerequisites_met .. "]"
                        )
                    else
                        if sb_v.o_hide_when_prerequisites_not_met == "true" then
                            -- hide! Nothing to do
                        else
                            if
                                sb_v.o_grey_when_prerequisites_not_met == "true" and
                                    sb_v.o_text_when_prerequisites_not_met == ""
                             then
                                h = h + 1
                                local l = h - 0.2
                                table.insert(formspec, "box[1," .. l .. ";43,1;#BBBBBB]")
                                table.insert(
                                    formspec,
                                    "label[3," ..
                                        h ..
                                            ";" ..
                                                yl_speak_up.message_button_option_prerequisites_not_met_default .. "]"
                                )
                            end
                            if
                                sb_v.o_grey_when_prerequisites_not_met == "true" and
                                    sb_v.o_text_when_prerequisites_not_met ~= ""
                             then
                                h = h + 1
                                local l = h - 0.2
                                table.insert(formspec, "box[1," .. l .. ";43,1;#BBBBBB]")
                                table.insert(
                                    formspec,
                                    "label[3," ..
                                        h ..
                                            ";" ..
                                                yl_speak_up.message_button_option_prerequisites_not_met_default ..
                                                    " : " .. sb_v.o_text_when_prerequisites_not_met .. "]"
                                )
                            end
                            if
                                sb_v.o_grey_when_prerequisites_not_met == "false" and
                                    sb_v.o_text_when_prerequisites_not_met == ""
                             then
                            -- no hide, no grey, no text
                            end
                            if
                                sb_v.o_grey_when_prerequisites_not_met == "false" and
                                    sb_v.o_text_when_prerequisites_not_met ~= ""
                             then
                                h = h + 1
                                table.insert(
                                    formspec,
                                    "button[1," ..
                                        h ..
                                            ";44,0.9;button_" ..
                                                sb_v.o_id .. ";" .. sb_v.o_text_when_prerequisites_not_met .. "]"
                                )
                                table.insert(
                                    formspec,
                                    "tooltip[button_" ..
                                        sb_v.o_id .. ";" .. sb_v.o_text_when_prerequisites_not_met .. "]"
                                )
                            end
                        end
                    end
                end

                counter = counter + 1
            end
        end
        h = h + 1
        table.insert(
            formspec,
            "button_exit[1," .. h .. ";44,0.9;button_exit;" .. yl_speak_up.message_button_option_exit .. "]"
        )
        table.insert(formspec, "tooltip[button_exit;" .. yl_speak_up.message_button_option_exit .. "]")

        table.insert(formspec, "container_end[]")
        table.insert(formspec, "container_end[]")
    end

    return table.concat(formspec, "")
end

-- receive fields

-- options

minetest.register_on_player_receive_fields(
    function(player, formname, fields)
        if formname ~= "yl_speak_up:optiondialog" then
            return
        end

        local pname = player:get_player_name()
        local n_id = yl_speak_up.speak_to[pname].n_id
        local d_id = yl_speak_up.speak_to[pname].d_id
        local dialog = yl_speak_up.speak_to[pname].dialog

        if fields then
            -- Button Cancel: Exit the form
            if fields.button_back or fields.quit then
                local temp_dialog = yl_speak_up.speak_to[pname].dialog

                yl_speak_up.speak_to[pname] = {}

                yl_speak_up.speak_to[pname].dialog = temp_dialog
                yl_speak_up.speak_to[pname].n_id = n_id
                yl_speak_up.speak_to[pname].d_id = d_id

                minetest.show_formspec(pname, "yl_speak_up:setdialog", get_fs_setdialog(player, n_id, d_id))
                return
            end

            -- Button Delete Option: Delete option dialog, but do not exit
            if fields.button_delete and fields.d_id and fields.o_id ~= yl_speak_up.text_new_option_id then
                local temp_dialog = yl_speak_up.speak_to[pname].dialog

                yl_speak_up.speak_to[pname] = {}

                yl_speak_up.speak_to[pname].dialog = temp_dialog
                yl_speak_up.speak_to[pname].n_id = n_id
                yl_speak_up.speak_to[pname].d_id = d_id

                yl_speak_up.speak_to[pname].o_id = yl_speak_up.text_new_option_id
                yl_speak_up.speak_to[pname].p_id = yl_speak_up.text_new_prerequisite_id
                yl_speak_up.speak_to[pname].r_id = yl_speak_up.text_new_result_id

                local o_id = yl_speak_up.text_new_option_id
                local p_id = yl_speak_up.text_new_prerequisite_id
                local r_id = yl_speak_up.text_new_result_id

                delete_option(fields.n_id, fields.d_id, fields.o_id)
                minetest.show_formspec(
                    pname,
                    "yl_speak_up:optiondialog",
                    get_fs_optiondialog(player, n_id, d_id, o_id, p_id, r_id)
                )
                return
            end

            if fields.d_text then
                yl_speak_up.speak_to[pname].d_text = fields.d_text
            end
            if fields.d_type then
                yl_speak_up.speak_to[pname].d_type = fields.d_type
            end

            -- When a new o_id is chosen, then all the other stuff is invalidated and we need to take values from the dialog or even default values
            if fields.o_id ~= nil and fields.o_id ~= yl_speak_up.speak_to[pname].o_id then
                local o_id = fields.o_id
                yl_speak_up.speak_to[pname].o_id = o_id
                yl_speak_up.speak_to[pname].p_id = yl_speak_up.text_new_prerequisite_id
                yl_speak_up.speak_to[pname].r_id = yl_speak_up.text_new_result_id

                -- Depends on the dialog
                if o_id == yl_speak_up.text_new_option_id then --New dialog
                    yl_speak_up.speak_to[pname].o_hide = "false"
                    yl_speak_up.speak_to[pname].o_grey = "false"
                    yl_speak_up.speak_to[pname].o_sort = ""
                    yl_speak_up.speak_to[pname].o_met = "Text when conditions are not met"
                    yl_speak_up.speak_to[pname].o_not_met = "Text when conditions are met"
                else -- existing dialog
                    yl_speak_up.speak_to[pname].o_hide =
                        dialog.n_dialogs[d_id].d_options[o_id].o_hide_when_prerequisites_not_met or "false"
                    yl_speak_up.speak_to[pname].o_grey =
                        dialog.n_dialogs[d_id].d_options[o_id].o_grey_when_prerequisites_not_met or "false"
                    yl_speak_up.speak_to[pname].o_sort = dialog.n_dialogs[d_id].d_options[o_id].o_sort or ""
                    yl_speak_up.speak_to[pname].o_met =
                        dialog.n_dialogs[d_id].d_options[o_id].o_text_when_prerequisites_not_met or
                        "Text when conditions are not met"
                    yl_speak_up.speak_to[pname].o_not_met =
                        dialog.n_dialogs[d_id].d_options[o_id].o_text_when_prerequisites_met or
                        "Text when conditions are met"
                end
            else
                if fields.o_hide then
                    yl_speak_up.speak_to[pname].o_hide = fields.o_hide
                end
                if fields.o_grey then
                    yl_speak_up.speak_to[pname].o_grey = fields.o_grey
                end
                if fields.o_sort then
                    yl_speak_up.speak_to[pname].o_sort = fields.o_sort
                end
                if fields.o_met then
                    yl_speak_up.speak_to[pname].o_met = fields.o_met
                end
                if fields.o_not_met then
                    yl_speak_up.speak_to[pname].o_not_met = fields.o_not_met
                end

                if fields.p_id ~= nil and fields.p_id ~= yl_speak_up.speak_to[pname].p_id then
                    yl_speak_up.speak_to[pname].p_id = fields.p_id
                    yl_speak_up.speak_to[pname].p_value = fields.p_value
                    yl_speak_up.speak_to[pname].p_type = fields.p_type
                end
                if fields.p_value then
                    yl_speak_up.speak_to[pname].p_value = fields.p_value
                end
                if fields.p_type then
                    yl_speak_up.speak_to[pname].p_type = fields.p_type
                end
                if fields.r_id ~= nil and fields.r_id ~= yl_speak_up.speak_to[pname].r_id then
                    yl_speak_up.speak_to[pname].r_id = fields.r_id
                    yl_speak_up.speak_to[pname].r_value = fields.r_value
                    yl_speak_up.speak_to[pname].r_type = fields.r_type
                end
                if fields.r_value then
                    yl_speak_up.speak_to[pname].r_value = fields.r_value
                end
                if fields.r_type then
                    yl_speak_up.speak_to[pname].r_type = fields.r_type
                end
            end
        end

        local o_id = fields.o_id or yl_speak_up.speak_to[pname].o_id
        local p_id = fields.p_id or yl_speak_up.speak_to[pname].p_id
        local r_id = fields.r_id or yl_speak_up.speak_to[pname].r_id

        -- Button Save
        if fields and fields.button_save and fields.n_id and fields.d_id then
            local temp_dialog = options_to_dialog(pname)

            save_dialog(n_id, temp_dialog)

            minetest.show_formspec(
                pname,
                "yl_speak_up:optiondialog",
                get_fs_optiondialog(player, fields.n_id, fields.d_id, fields.o_id, fields.p_id, fields.r_id)
            )
        end

        minetest.show_formspec(
            pname,
            "yl_speak_up:optiondialog",
            get_fs_optiondialog(player, n_id, d_id, o_id, p_id, r_id)
        )
    end
)

-- dialog

minetest.register_on_player_receive_fields(
    function(player, formname, fields)
        if formname ~= "yl_speak_up:setdialog" then
            return
        end

        local pname = player:get_player_name()
        local n_id = yl_speak_up.speak_to[pname].n_id
        local d_id = yl_speak_up.speak_to[pname].d_id or yl_speak_up.text_new_dialog_id

        -- Button Cancel: Exit the form
        if fields.button_cancel or fields.quit then
            yl_speak_up.speak_to[pname] = nil
            minetest.close_formspec(pname, "yl_speak_up:setdialog")
            return
        end

        -- Button Options with valid d_id: Show options formspec
        if fields.button_option and fields.d_id and fields.d_id ~= yl_speak_up.text_new_dialog_id then
            local o_id = yl_speak_up.text_new_option_id
            local p_id = yl_speak_up.text_new_prerequisite_id
            local r_id = yl_speak_up.text_new_result_id

            -- Context
            yl_speak_up.speak_to[pname].d_id = fields.d_id
            yl_speak_up.speak_to[pname].o_id = o_id
            yl_speak_up.speak_to[pname].p_id = p_id
            yl_speak_up.speak_to[pname].r_id = r_id

            minetest.show_formspec(
                pname,
                "yl_speak_up:optiondialog",
                get_fs_optiondialog(player, n_id, fields.d_id, o_id, p_id, r_id)
            )
            return
        end

        -- Button Options with invalid d_id: Show options formspec
        if fields.button_option and fields.d_id and fields.d_id == yl_speak_up.text_new_dialog_id then
            yl_speak_up.speak_to[pname].d_id = yl_speak_up.text_new_dialog_id
            minetest.show_formspec(pname, "yl_speak_up:optiondialog", get_error_message())
            return
        end

        -- Button Save: Save the settings, but do not exit
        if fields.button_save and fields.d_id then
            local dialog = fields_to_dialog(pname, fields)
            save_dialog(n_id, dialog)
            yl_speak_up.speak_to[pname].dialog = dialog

            if yl_speak_up.speak_to[pname].obj then
                local obj = yl_speak_up.speak_to[pname].obj
                local ent = obj:get_luaentity()
                if ent ~= nil then
                    ent.yl_speak_up.npc_name = dialog.n_npc
                    ent.yl_speak_up.npc_description = dialog.n_description
                    
                    local i_text = dialog.n_npc .. "\n" .. dialog.n_description .. "\n" .. yl_speak_up.infotext
                    obj:set_properties({infotext = i_text})
                    obj:set_nametag_attributes({color="#00ff00", text=dialog.n_npc})
                end
            end

            minetest.show_formspec(pname, "yl_speak_up:setdialog", get_fs_setdialog(player, n_id, d_id))
            return
        end

        -- Button Delete: Delete dialog, but do not exit
        if fields.button_delete and fields.d_id then
            delete_dialog(n_id, fields.d_id)
            yl_speak_up.speak_to[pname].d_id = yl_speak_up.text_new_dialog_id
            minetest.show_formspec(
                pname,
                "yl_speak_up:setdialog",
                get_fs_setdialog(player, n_id, yl_speak_up.text_new_dialog_id)
            )
        end

        -- Change in Dropdown List: Show dialog formspec again with different dialog selected
        if fields.d_id then
            yl_speak_up.speak_to[pname].d_id = fields.d_id
            minetest.show_formspec(pname, "yl_speak_up:setdialog", get_fs_setdialog(player, n_id, fields.d_id))
        end
    end
)

-- talk

minetest.register_on_player_receive_fields(
    function(player, formname, fields)
        if formname ~= "yl_speak_up:talk" then
            return
        end

        local pname = player:get_player_name()
        local o = ""

	-- start edit mode (requires npc_talk_owner)
	if fields.button_start_edit_mode then
            if(  not(minetest.check_player_privs(player, {npc_talk_owner=true}))
             and not(minetest.check_player_privs(player, {npc_master=true}))) then
                minetest.chat_send_player(pname, "Sorry. You do not have the npc_talk_owner or npc_master priv.")
                return
	    end
	    -- TODO: check if this particular NPC is really owned by this player
	    -- enter edit mode with that particular NPC
            yl_speak_up.edit_mode[pname] = yl_speak_up.speak_to[pname].n_id
	    -- start a new chat - but this time in edit mode
            yl_speak_up.speak_to[pname].d_id = nil
            minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, yl_speak_up.speak_to[pname].n_id, nil))
	    return
        -- end edit mode (does not require the priv; will only switch back to normal behaviour)
        elseif fields.button_end_edit_mode then
            yl_speak_up.edit_mode[pname] = nil
	    -- start a new chat - but this time in normal mode
            yl_speak_up.speak_to[pname].d_id = nil
            minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, yl_speak_up.speak_to[pname].n_id, nil))
	    return
       end

        if fields.quit or fields.button_exit then
            -- Formspec was quit
            yl_speak_up.speak_to[pname] = nil
            return
        end

        if fields.button_up then
            yl_speak_up.speak_to[pname].option_index =
                yl_speak_up.speak_to[pname].option_index + yl_speak_up.max_number_of_buttons
            minetest.show_formspec(
                pname,
                "yl_speak_up:talk",
                get_fs_talkdialog(player, yl_speak_up.speak_to[pname].n_id, yl_speak_up.speak_to[pname].d_id)
            )
            return
        elseif fields.button_down then --and yl_speak_up.speak_to[pname].option_index > yl_speak_up.max_number_of_buttons then
            yl_speak_up.speak_to[pname].option_index =
                yl_speak_up.speak_to[pname].option_index - yl_speak_up.max_number_of_buttons
            if yl_speak_up.speak_to[pname].option_index < 0 then
                yl_speak_up.speak_to[pname].option_index = 1
            end
            minetest.show_formspec(
                pname,
                "yl_speak_up:talk",
                get_fs_talkdialog(player, yl_speak_up.speak_to[pname].n_id, yl_speak_up.speak_to[pname].d_id)
            )
            return
        else
            yl_speak_up.speak_to[pname].option_index = 1
        end

        for k, v in pairs(fields) do
            local s = string.split(k, "_")

            if
                s[1] == "button" and s[2] ~= nil and s[2] ~= "" and s[2] ~= "exit" and s[2] ~= "back" and s[3] ~= nil and
                    s[2] ~= "up" and
                    s[2] ~= "down"
             then
                o = s[2] .. "_" .. s[3]
            end
        end

	-- Is the player working on this particular npc?
	local edit_mode = (yl_speak_up.edit_mode[pname] == yl_speak_up.speak_to[pname].n_id)

	if not(edit_mode) and o == "" then
            return
        end

        -- Let's check if the button was among the "allowed buttons". Only those may be executed
        if not(edit_mode) and (yl_speak_up.speak_to[pname].allowed and yl_speak_up.speak_to[pname].allowed[o] == false) then
            return
        end

        -- button was clicked, now let's execute the results

        local d_id = yl_speak_up.speak_to[pname].d_id

        local dialog = yl_speak_up.speak_to[pname].dialog

	-- in edit mode: another dialog was selected
        if ( o == "" and edit_mode) then
            -- if nothing better can be found: keep the old dialog
            local show_dialog = d_id
	    -- "New dialog" button or option from dropdown menu was selected
	    if(fields.show_new_dialog or fields.d_id and fields.d_id == yl_speak_up.text_new_option_id) then
                -- TODO
            -- dropdown menu was used; provided the dialog exists (and it's not the "New dialog" option)
            elseif(fields.d_id and fields.d_id ~= show_dialog and dialog.n_dialogs[fields.d_id]) then
                show_dialog = fields.d_id
            -- in edit mode: prev_dialog_../next_dialog_.. was selected
            else
                for k,v in pairs(dialog.n_dialogs) do
                    if(fields["prev_dialog_"..k]) then
                        show_dialog = k
                    elseif(fields["next_dialog_"..k]) then
                        show_dialog = k
	            end
	        end
	    end
            yl_speak_up.speak_to[pname].d_id = show_dialog
            minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, yl_speak_up.speak_to[pname].n_id, show_dialog))
	    return
	end


        local n_dialog = dialog.n_dialogs[d_id]

        local d_option = n_dialog.d_options[o]

        -- Let's do something if results exist
        if d_option.o_results ~= nil then
            for k, v in pairs(d_option.o_results) do
		-- in edit_mode, only the switching to the next dialog is executed (we want to edit,
		-- not solve quests, get/take items, teleport...)
                if not(edit_mode) and v.r_type == "give_item" then
                    local item = ItemStack(v.r_value)

                    if minetest.registered_items[item:get_name()] ~= nil then
                        local r = player:get_inventory():add_item("main", item)
                    else
                        say("Item not found!")
                    end
                end
                if not(edit_mode) and v.r_type == "take_item" then
                    local item = ItemStack(v.r_value)

                    if minetest.registered_items[item:get_name()] ~= nil then
                        local r = player:get_inventory():remove_item("main", item)
                    else
                        say("Item not found!")
                    end
                end
                if not(edit_mode) and v.r_type == "move" then
                    local target_pos = nil
                    local target_pos_valid = false

                    --pos like (100,20,400)
                    if minetest.string_to_pos(v.r_value) then
                        target_pos = minetest.string_to_pos(v.r_value)
                        target_pos_valid = true
                    end

                    --pos like 100,20,400
                    local maybe = string.split(v.r_value, ",")
                    if not target_pos_valid and maybe and tonumber(maybe[1]) and tonumber(maybe[2]) and tonumber(maybe[3]) and maybe[4] == nil and 
                        tonumber(maybe[1]) <= 32000 and tonumber(maybe[1]) >= -32000 and
                        tonumber(maybe[2]) <= 32000 and tonumber(maybe[2]) >= -32000 and
                        tonumber(maybe[3]) <= 32000 and tonumber(maybe[3]) >= -32000 then
                            target_pos = {x=maybe[1],y=maybe[2],z=maybe[3]}
                            target_pos_valid = true
                    end
                    
                    --pos like {x=100,y=20,z=400}
                    if not target_pos_valid and string.sub(v.r_value,1,1) == "{" and string.sub(v.r_value,-1,-1) == "}" then
                        local might_be_pos = minetest.deserialize("return " .. v.r_value)
                        if tonumber(might_be_pos.x) and tonumber(might_be_pos.x) <= 32000 and tonumber(might_be_pos.x) >= -32000 and
                        tonumber(might_be_pos.y) and tonumber(might_be_pos.y) <= 32000 and tonumber(might_be_pos.y) >= -32000 and
                        tonumber(might_be_pos.z) and tonumber(might_be_pos.z) <= 32000 and tonumber(might_be_pos.z) >= -32000 then
                            target_pos = might_be_pos
                            target_pos_valid = true
                        end

                    end
                    
                    if target_pos_valid == true then
                        player:set_pos(target_pos)
                        if vector.distance(player:get_pos(),target_pos) >= 2 then
                            say("Something went wrong! Player wasn't moved properly.")
                        end
                    end

                    -- Debug
                    if target_pos_valid == false then
                        local obj = yl_speak_up.speak_to[pname].obj
                        local n_id = yl_speak_up.speak_to[pname].n_id
                        local npc = get_number_from_id(n_id)
                        if obj:get_luaentity() and tonumber(npc) then
                            minetest.log("error","[MOD] yl_speak_up: NPC with ID n_"..npc.." at position "..minetest.pos_to_string(obj:get_pos(),0).." could not move player "..pname.." because the content of "..v.r_id.." is wrong:"..dump(v.r_value))
                        else
                            minetest.log("error","[MOD] yl_speak_up: NPC with unknown ID or without proper object could not move player "..dump(pname).." because the content of "..v.r_id.." is wrong:"..dump(v.r_value))
                        end
                    end

                end
                if not(edit_mode) and v.r_type == "function" then
                    local code = v.r_value
                    if code:byte(1) == 27 then
                        local obj = yl_speak_up.speak_to[pname].obj
                        local n_id = yl_speak_up.speak_to[pname].n_id
                        local npc = get_number_from_id(n_id)
                        if obj:get_luaentity() and tonumber(npc) then
                            minetest.log("error","[MOD] yl_speak_up: NPC with ID n_"..npc.." at position "..minetest.pos_to_string(obj:get_pos(),0).." could not compile the content of "..v.r_id.." :"..dump(v.r_value) .. " because of illegal bytecode for player "..pname)
                        else
                            minetest.log("error","[MOD] yl_speak_up: NPC with ID unknown could not compile the content of "..v.r_id.." :"..dump(v.r_value) .. " for player unknown because of illegal bytecode")
                        end
                    end

                    local f, msg = loadstring("return function(player) " .. code .. " end")

                    if not f then
                        local obj = yl_speak_up.speak_to[pname].obj
                        local n_id = yl_speak_up.speak_to[pname].n_id
                        local npc = get_number_from_id(n_id)
                        if obj:get_luaentity() and tonumber(npc) then
                            minetest.log("error","[MOD] yl_speak_up: NPC with ID n_"..npc.." at position "..minetest.pos_to_string(obj:get_pos(),0).." could not compile the content of "..v.r_id.." :"..dump(v.r_value) .. " for player "..pname)
                        else
                            minetest.log("error","[MOD] yl_speak_up: NPC with ID unknown could not compile the content of "..v.r_id.." :"..dump(v.r_value) .. " for player unknown")
                        end
                    else
                    

                        local func = f()

                        local ok, ret = pcall(func,pname)

                        if not ok then
                            local obj = yl_speak_up.speak_to[pname].obj
                            local n_id = yl_speak_up.speak_to[pname].n_id
                            local npc = get_number_from_id(n_id)
                            if obj:get_luaentity() and tonumber(npc) then
                                minetest.log("error","[MOD] yl_speak_up: NPC with ID n_"..npc.." at position "..minetest.pos_to_string(obj:get_pos(),0).." could not execute the content of "..v.r_id.." :"..dump(v.r_value) .. " for player "..pname)
                            else
                                minetest.log("error","[MOD] yl_speak_up: NPC with ID unknown could not execute the content of "..v.r_id.." :"..dump(v.r_value) .. " for player unknown")
                            end
                        end
                    end
                    
                end
                if v.r_type == "dialog" then
                    if dialog.n_dialogs[v.r_value] ~= nil then
                        yl_speak_up.speak_to[pname].d_id = v.r_value
                        local n_id = yl_speak_up.speak_to[pname].n_id
                        minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, n_id, v.r_value))
                    else
                        say("This dialog does not exist")
                    end
                end
                if v.r_type == "auto" then
                    say("auto forward")
                end
            end
        end
    end
)

-- Make the NPC talk

function yl_speak_up.config(clicker, npc)
    if not clicker and not clicker:is_player() then
        return
    end
    if not npc then
        return
    end

    local npc_id = npc:get_luaentity().yl_speak_up.id
    local n_id = "n_" .. npc_id
    local pname = clicker:get_player_name()

    yl_speak_up.speak_to[pname] = {}
    yl_speak_up.speak_to[pname].n_id = n_id -- Memorize which player talks to which NPC
    yl_speak_up.speak_to[pname].d_id = yl_speak_up.text_new_dialog_id -- The only d_id we can rely on existing
    yl_speak_up.speak_to[pname].dialog = load_dialog(n_id) -- Load the dialog and see what we can do with it
    yl_speak_up.speak_to[pname].obj = npc

    minetest.show_formspec(
        pname,
        "yl_speak_up:setdialog",
        get_fs_setdialog(clicker, n_id, yl_speak_up.text_new_dialog_id)
    )
end

--###
-- Mob functions
--###

function yl_speak_up.on_rightclick(self, clicker)
    --local item = clicker:get_wielded_item()
    local name = clicker:get_player_name()

    -- Take the mob only with net or lasso
    if self.owner and self.owner == name then
        if mobs:capture_mob(self, clicker, nil, 100, 100, true, nil) then
            return
        end
    end

    -- protect npc with mobs:protector
    if mobs:protect(self, clicker) then
        return
    end

    -- bring up the dialog options
    if clicker then
        yl_speak_up.talk(self, clicker)
        return
    end
end

function yl_speak_up.on_spawn(self)
    --Let's assign an ID

    local m_talk = yl_speak_up.talk_after_spawn or true
    local m_id = yl_speak_up.number_of_npcs + 1

    yl_speak_up.number_of_npcs = m_id
    yl_speak_up.modstorage:set_int("amount", m_id)

    yl_speak_up.mob_table[m_id] = "yl_speak_up:test_npc"

    self.yl_speak_up = {
        talk = m_talk,
        id = m_id,
        textures = self.textures
    }

    --Let's protect it
    self.protected = true
    self.tamed = true
    self.object:set_armor_groups({immortal = 100})

    minetest.log(
        "action",
        "[MOD] yl_speak_up: NPC with ID n_" ..
            self.yl_speak_up.id .. " spawned at " .. minetest.pos_to_string(self.object:get_pos(), 0)
    )

    --Let's do it only once
    return true
end

function yl_speak_up.after_activate(self, staticdata, def, dtime)
    minetest.log(
        "action",
        "[MOD] yl_speak_up: NPC with ID n_" ..
            self.yl_speak_up.id .. " activated at " .. minetest.pos_to_string(self.object:get_pos(), 0)
    )

    if yl_speak_up.status == 2 then
        self.object:remove()
        return true
    end

    if self.yl_speak_up and self.yl_speak_up.skin then
        local tex = self.yl_speak_up.skin
        self.object:set_properties({textures = {tex[1], tex[2], tex[3], tex[4]}})
    end

    if yl_speak_up.infotext then
        local i_text = ""
        if self.yl_speak_up.npc_name then
            i_text = i_text .. self.yl_speak_up.npc_name .. "\n"
        end
        if self.yl_speak_up.npc_description then
            i_text = i_text .. self.yl_speak_up.npc_description .. "\n"
        end
        i_text = i_text .. yl_speak_up.infotext
        self.object:set_properties({infotext = i_text})
    end

    if self.yl_speak_up.npc_name then
        self.object:set_nametag_attributes({color="#00ff00", text=self.yl_speak_up.npc_name})
    end

end

function yl_speak_up.talk(self, clicker)

    if not clicker and not clicker:is_player() then
        return
    end
    if not self then
        return
    end
    if not self.yl_speak_up or not self.yl_speak_up.id then
        return
    end

    if not self.yl_speak_up or not self.yl_speak_up.talk or self.yl_speak_up.talk~=true then
        return
    end

    local npc_id = self.yl_speak_up.id
    local n_id = "n_" .. npc_id
    local pname = clicker:get_player_name()

    yl_speak_up.speak_to[pname] = {}
    yl_speak_up.speak_to[pname].n_id = n_id -- Memorize which player talks to which NPC
    yl_speak_up.speak_to[pname].dialog = load_dialog(n_id) -- Load the dialog and see what we can do with it
    yl_speak_up.speak_to[pname].textures = self.yl_speak_up.textures
    yl_speak_up.speak_to[pname].option_index = 1
    yl_speak_up.speak_to[pname].obj = self.object

    minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(clicker, n_id))
end

-- ###
-- Fashion
-- ###

local function cape2texture(t)
    return "yl_speak_up_mask_cape.png^[combine:32x64:56,20=" .. t
end

local function shield2texture(t)
    return "yl_speak_up_mask_shield.png^[combine:32x64:0,0=(" .. t .. ")"
end

local function textures2skin(textures)
    local temp = {}
    -- Cape

    local cape = cape2texture(textures[1])

    -- Main

    local main = textures[2]

    -- left (Shield)

    local left = shield2texture(textures[3])

    -- right (Sword)

    local right = textures[4]

    temp = {cape, main, left, right}

    return temp
end

local function set_textures(obj, textures) -- this function takes the base name of the textures, converts them to usable textures and stores those on the NPC
    local skins = textures2skin(textures)

    local ent = obj:get_luaentity()
    ent.yl_speak_up.skin = skins

    obj:set_properties({textures = skins})
end

local function get_npc_skins(skin)
    local retstring = "yl_speak_up_main_default.png"
    local rettable = {"yl_speak_up_main_default.png"}
    local temp = {}

    -- get the files out of modpath
    local mp_list = minetest.get_dir_list(yl_speak_up.modpath .. DIR_DELIM .. "textures", false)

    -- get the files out of worlddir
    local wp_list =
        minetest.get_dir_list(
        yl_speak_up.worldpath .. DIR_DELIM .. "worldmods" .. DIR_DELIM .. "yl_npc" .. DIR_DELIM .. "textures",
        false
    )

    -- Let's join both lists.
    table.insert_all(temp, mp_list)
    table.insert_all(temp, wp_list)

    --[[ Let's see if the files are the ones we want. Format is 
    yl_npc_main_name.png <-- Those are the ones we want
    yl_npc_cape_name.png
    yl_npc_item_name.png
    ]]--
    local index = 1
    local retindex = 1

    for _, v in pairs(temp) do
        local s = string.split(v, "_")
        if s[1] == "yl" and s[2] == "npc" and s[3] == "main" then
            index = index + 1
            retstring = retstring .. "," .. v
            table.insert(rettable, v)
            if v == skin then
                retindex = index
            end
        end
    end

    return rettable, retstring, retindex
end

local function get_npc_capes(cape)
    local retstring = "yl_npc_cape_default.png"
    local rettable = {"yl_npc_cape_default.png"}
    local temp = {}

    -- get the files out of modpath
    local mp_list = minetest.get_dir_list(yl_speak_up.modpath .. DIR_DELIM .. "textures", false)

    -- get the files out of worlddir
    local wp_list =
        minetest.get_dir_list(
        yl_speak_up.worldpath .. DIR_DELIM .. "worldmods" .. DIR_DELIM .. "yl_npc" .. DIR_DELIM .. "textures",
        false
    )

    -- Let's join both lists.
    table.insert_all(temp, mp_list)
    table.insert_all(temp, wp_list)

    --[[ Let's see if the files are the ones we want. Format is 
    yl_npc_main_name.png
    yl_npc_cape_name.png <-- Those are the ones we want
    yl_npc_item_name.png
    ]]--
    local index = 1
    local retindex = 1

    for _, v in pairs(temp) do
        local s = string.split(v, "_")

        if s[1] == "yl" and s[2] == "npc" and s[3] == "cape" then
            index = index + 1
            retstring = retstring .. "," .. v
            table.insert(rettable, v)
            if cape ~= "" and v == cape then
                retindex = index
            end
        end
    end

    return rettable, retstring, retindex
end

local function create_preview(main_skin)
    if main_skin == nil or main_skin == "" then
        main_skin = "default_greyscale.png"
    end

    local player_skin = "(" .. main_skin .. ")"
    local skin = ""

    -- Consistent on both sizes:
    --Chest
    skin = skin .. "([combine:16x32:-16,-12=" .. player_skin .. "^[mask:yl_speak_up_mask_chest.png)^"

    --Head
    skin = skin .. "([combine:16x32:-4,-8=" .. player_skin .. "^[mask:yl_speak_up_mask_head.png)^"

    --Hat
    skin = skin .. "([combine:16x32:-36,-8=" .. player_skin .. "^[mask:yl_speak_up_mask_head.png)^"
    --Right Arm
    skin = skin .. "([combine:16x32:-44,-12=" .. player_skin .. "^[mask:yl_speak_up_mask_rarm.png)^"
    --Right Leg
    skin = skin .. "([combine:16x32:0,0=" .. player_skin .. "^[mask:yl_speak_up_mask_rleg.png)^"

    -- Left Arm
    skin = skin .. "([combine:16x32:-24,-44=" .. player_skin .. "^[mask:(yl_speak_up_mask_rarm.png^[transformFX))^"
    --Left Leg
    skin = skin .. "([combine:16x32:-12,-32=" .. player_skin .. "^[mask:(yl_speak_up_mask_rleg.png^[transformFX))^"

    -- Add overlays for 64x skins. these wont appear if skin is 32x because it will be cropped out
    --Chest Overlay
    skin = skin .. "([combine:16x32:-16,-28=" .. player_skin .. "^[mask:yl_speak_up_mask_chest.png)^"
    --Right Arm Overlay
    skin = skin .. "([combine:16x32:-44,-28=" .. player_skin .. "^[mask:yl_speak_up_mask_rarm.png)^"
    --Right Leg Overlay
    skin = skin .. "([combine:16x32:0,-16=" .. player_skin .. "^[mask:yl_speak_up_mask_rleg.png)^"
    --Left Arm Overlay
    skin = skin .. "([combine:16x32:-40,-44=" .. player_skin .. "^[mask:(yl_speak_up_mask_rarm.png^[transformFX))^"
    --Left Leg Overlay
    skin = skin .. "([combine:16x32:4,-32=" .. player_skin .. "^[mask:(yl_speak_up_mask_rleg.png^[transformFX))"

    -- Full Preview
    skin = "(((" .. skin .. ")^[resize:64x128)^[mask:yl_speak_up_transform.png)"

    return skin
end

local function get_fs_fashion(pname)
    local textures = yl_speak_up.speak_to[pname].textures

    local maintable, mainlist, mainindex = get_npc_skins(textures[2])
    local capetable, capelist, capeindex = get_npc_capes(textures[1])
    local preview = create_preview(textures[2])

    local formspec = {
        "formspec_version[3]",
        "size[13.4,9.5]",
        "dropdown[0.3,0.2;4,0.75;set_skin;",
        mainlist,
        ";",
        mainindex,
        "]",
        "label[4.6,0.45;",
        yl_speak_up.speak_to[pname].n_id,
        "]",
        "label[6,0.45;",
        yl_speak_up.speak_to[pname].n_npc,
        "]",
        "dropdown[9.1,0.2;4,0.75;set_cape;",
        capelist,
        ";",
        capeindex,
        "]",
        "field[0.3,3.2;4,0.75;set_sword;;",
        textures[4],
        "]",
        "field[9.1,3.2;4,0.75;set_shield;;",
        textures[3],
        "]",
        "field_close_on_enter[set_sword;false]",
        "field_close_on_enter[set_shield;false]",
        "image[0.3,1;4,2;",
        textures[2],
        "]", -- Main
        "image[9.1,1;4,2;",
        textures[1],
        "]", -- Cape
        "image[0.3,4.2;4,4;",
        textures[4],
        "]", -- Sword
        "image[9.1,4.2;4,4;",
        textures[3],
        "]", --textures[3],"]", -- Shield
        "image[4.7,1;4,8;",
        preview,
        "]",
        "button_exit[0.3,8.4;3,0.75;button_cancel;Cancel]",
        "button[10.1,8.4;3,0.75;button_save;Save]"
    }
    return table.concat(formspec, "")
end

minetest.register_on_player_receive_fields( --fashion
    function(player, formname, fields)
        if formname ~= "yl_speak_up:fashion" then
            return
        end

        local pname = player:get_player_name()
        local textures = yl_speak_up.speak_to[pname].textures

        if fields then
            if fields.quit or fields.button_cancel then
                yl_speak_up.speak_to[pname] = nil
                return
            end

            if fields.set_cape then
                textures[1] = fields.set_cape
            end
            if fields.set_skin then
                textures[2] = fields.set_skin
            end
            if fields.set_shield then
                textures[3] = fields.set_shield
            end
            if fields.set_sword then
                textures[4] = fields.set_sword
            end

            if fields.button_save then
                local obj = yl_speak_up.speak_to[pname].obj
                if obj ~= nil and obj:get_luaentity() ~= nil then
                    -- save textures
                    yl_speak_up.speak_to[pname].skins = textures2skin(textures)
                    set_textures(obj, textures)
                end
            end

        --yl_speak_up.speak_to[pname].textures = textures
        end

        minetest.show_formspec(pname, "yl_speak_up:fashion", get_fs_fashion(pname))
    end
)

function yl_speak_up.fashion(player, obj)
    local luaentity = obj:get_luaentity()
    local pname = player:get_player_name()
    local npc_id = luaentity.yl_speak_up.id
    local skins = luaentity.yl_speak_up.skins
    local n_id = "n_" .. npc_id
    local t = luaentity.textures

    yl_speak_up.speak_to[pname] = {}
    yl_speak_up.speak_to[pname].n_id = n_id
    yl_speak_up.speak_to[pname].obj = obj
    yl_speak_up.speak_to[pname].textures = t
    yl_speak_up.speak_to[pname].skins = textures2skin(t)

    local dialog = load_dialog(n_id)
    if next(dialog) then
        yl_speak_up.speak_to[pname].n_npc = dialog.n_npc
    else
        yl_speak_up.speak_to[pname].n_npc = "Unknown"
    end

    minetest.show_formspec(pname, "yl_speak_up:fashion", get_fs_fashion(pname))
end