-----------------------------------------------------------------------------
-- This can be customized for each server.
-----------------------------------------------------------------------------

-----------------------------------------------------------------------------
-- Placeholders (i.e. $NPC_NAME$) in texts
-----------------------------------------------------------------------------
-- this contains custom functions that you can override on your server
-- please take a look at the example code!

-- replace some variables in the text the NPC speaks and which the player can use to reply
-- pname: the name of the player that is talking to the NPC;
-- Note: If you want to change this function, best call the original as well after
--       applying your custom changes.
yl_speak_up.replace_vars_in_text = function(text, dialog, pname)
	local subs = {
		MY_NAME = dialog.n_npc,
		NPC_NAME = dialog.n_npc,
		OWNER_NAME = dialog.npc_owner,
		PLAYER_NAME = pname,
	}

	local day_time_name = "day"
	local day_time = minetest.get_timeofday()
	if(day_time < 0.5) then
		day_time_name = "morning"
	elseif(day_time < 0.75) then
		day_time_name = "afternoon"
	else
		day_time_name = "evening"
	end
	subs.GOOD_DAY = "Good "..day_time_name
	subs.good_DAY = "good "..day_time_name

	-- Note: the $ char is a special one. It needs to be escaped with %$ in lua.
	-- Note: when substitution argument is a table, we look up
	-- substitutions in it using substring captured by "()" in
	-- pattern. "[%a_]+" means one or more letter or underscore.
	-- If lookup returns nil, then no substitution is made.
	text = string.gsub(text or "", "%$([%a_]+)%$", subs)

	return text
end


-----------------------------------------------------------------------------
-- Custom preconditions
-----------------------------------------------------------------------------

-- When you change an existing texts NPC that make use of that precondition will no
-- longer be able to recognize it. You have to reconfigure all those NPC!
-- Adding new texts is no problem.
yl_speak_up.custom_server_functions.precondition_descriptions = {
	"(internal) hour of ingame day",
	"(internal) player's health points",
	"(internal) player has priv:",
}

-- please return a useful value depending on the function;
-- parameter:
-- 	player		the player object
-- 	desc		entry from yl_speak_up.custom_server_functions.precondition_descriptions above
-- 	precondition	contains the data of the precondition for additional information;
-- 			precondition.p_var_cmp_value contains a user-specified value against which
-- 			the return value of this function is checked. This depends on
-- 			precondition.p_operator. Depending on the operator, precondition.p_var_cmp_value
-- 			may also be used as a parameter to this function.
-- 			Just make sure to tell your users what return values they shall expect and which
-- 			operators make sense!
yl_speak_up.custom_server_functions.precondition_eval = function(player, descr, precondition)

	if(descr == "(internal) hour of ingame day") then
		-- timeofday is between 0..1; translate to 24 hours
		return math.floor((minetest.get_timeofday() * 24)+0.5)

	elseif(descr == "(internal) player's health points") then
		return player:get_hp()

	elseif(descr == "(internal) player has priv:") then
		-- the name of the priv is derived from the parameter
		local ret = minetest.check_player_privs(player,
				minetest.string_to_privs(tostring(precondition.p_var_cmp_value)))
		-- evaluate the parameter directly
		if(not(ret) or precondition.p_operator == "true_for_param"
		            or precondition.p_operator == "false_for_param") then
			return ret
		end
		-- return the parameter for == / != comparison
		return tostring(precondition.p_var_cmp_value)

	-- if this custom server function does not exist: return false
	else
		return false
	end
end


-- a custom precondition; still works, but less useful than the above method.
-- Please use
-- 	yl_speak_up.custom_server_functions.precondition_descriptions = {..}
-- and
--	1yl_speak_up.custom_server_functions.precondition_eval(player, descr, precondition)
-- instead!
-- has to return either true (=precondition is fulfilled) or false (=precondition is not fulfilled)
-- Note: This function will be called often. Make it efficient!
yl_speak_up.precondition_custom = function(player, param)
	minetest.chat_send_player(player:get_player_name(),
		"Checking custom precondition with parameter \""..tostring(param).."\"..")
	-- return if your precondition is fulfilled (true) or not (false)
	return true
end


-----------------------------------------------------------------------------
--  Custom effects
-----------------------------------------------------------------------------

-- a custom effect;
-- has to return true (=effect was executed successfully) or false (=effect failed for some reason)
yl_speak_up.effect_custom = function(player, param)
	minetest.chat_send_player(player:get_player_name(),
		"Executing custom effect with parameter \""..tostring(param).."\"..")
	-- return true if your effect executed successfuly, and false if not
	-- (only relevant for following on_failure effects)
        return true
end


-----------------------------------------------------------------------------
--  Custom actions
-----------------------------------------------------------------------------

-- a custom action (the formspec shown to the player);
-- overwrite this function on your server with a custom one that shows the formspec
-- that you want!
yl_speak_up.get_fs_action_custom = function(player, param)
	local pname = player:get_player_name()
	local dialog = yl_speak_up.speak_to[pname].dialog
	return "size[8.5,4.0]"..
		"button[0.2,0.0;2.0,0.9;back_to_talk;Back to talk]"..
		"button[4.75,0.0;3.0,0.9;finished_action;Stare back]"..
		"button[4.75,0.8;3.0,0.9;failed_action;Fail to stare back]"..
		"tooltip[back_to_talk;Click here if you want to abort/cancel.]"..
		"tooltip[failed_action;Click here if you want the action to FAIL.]"..
		"tooltip[finished_action;Click here if you want the action to be a SUCCESS.]"..
		"label[0.5,1.7;"..minetest.formspec_escape(
			"["..(dialog.n_npc or "- ? -").." stares expectantly at you.]").."]"..
		"label[0.5,2.5;Your custom parameter is:]"..
		"label[1.5,3.0;"..minetest.formspec_escape(tostring(param)).."]"..
		"label[0.5,3.5;Overwrite this function with a custom one!]"
end


-- a custom action (checking of the input);
-- overwrite this function on your server with a custom one that checks the
-- input to your formspec - but don't forget to call the necessary functions
-- as shown here
yl_speak_up.input_fs_action_custom = function(player, formname, fields)
	-- back from error_msg? then show the formspec again
	if(fields.back_from_error_msg) then
		yl_speak_up.show_fs(player, "action_custom", nil)
		return
	end
	local pname = player:get_player_name()
	local a_id = yl_speak_up.speak_to[pname].a_id
	if(fields.back_to_talk) then
		-- the action was aborted
		yl_speak_up.execute_next_action(player, a_id, nil)
		return
	end
	if(fields.failed_action) then
		-- the action failed
		yl_speak_up.execute_next_action(player, a_id, false)
		return
	end
	if(fields.finished_action) then
		-- the action was a success
		yl_speak_up.execute_next_action(player, a_id, true)
		return
	end
	-- else show a message to the player that he ought to decide
	yl_speak_up.show_fs(player, "msg", {
		input_to = "yl_speak_up:action_custom",
		formspec = "size[7,1.0]"..
			"label[0.2,-0.2;"..
				"Please click either on \"Stare back\" or \"Back to talk\"!]"..
				"button[2,0.5;1.5,0.9;back_from_error_msg;Back]"})
end

-----------------------------------------------------------------------------
-- Custom preconditions and effects (functions; they have the type "evaluate")
-----------------------------------------------------------------------------
-- each entry in the table has the following format:
-- key: for display in edit options dialog and dropdown menu,
--	function_name: name of the function that shall be called
--      description: long description of what the function does,
--      param1_text: label for the input field for param1 (if empty, no input field is offered)
--      param1_desc: mouseover text for the input field for param1
--      ...
--      param9_text: label for the input field for param1
--      param9_desc: mouseover text for the input field for param1
--
-- preconditions:
yl_speak_up.custom_functions_p_ = {}
-- actions: (not yet used)
yl_speak_up.custom_functions_a_ = {}
-- results:
yl_speak_up.custom_functions_r_ = {}

-- example function for preconditions:
yl_speak_up.custom_functions_p_[ "example function" ] = {
	function_call = "yl_speak_up.custom_example_function",
	description = "This function is just an example. It does nothing.",
	param1_text = "1. Parameter:",
	param1_desc = "This is the value passed to the function as first parameter.",
	param2_text = "2. Parameter:",
	param2_desc = "This is the value passed to the function as second parameter.",
	param3_text = "3. Parameter:",
	param3_desc = "This is the value passed to the function as 3. parameter.",
	param4_text = "4. Parameter:",
	param4_desc = "This is the value passed to the function as 4. parameter.",
	param5_text = "5. Parameter:",
	param5_desc = "This is the value passed to the function as 5. parameter.",
	param6_text = "6. Parameter:",
	param6_desc = "This is the value passed to the function as 6. parameter.",
	param7_text = "7. Parameter:",
	param7_desc = "This is the value passed to the function as 7. parameter.",
	param8_text = "8. Parameter:",
	param8_desc = "This is the value passed to the function as 8. parameter.",
	param9_text = "9. Parameter:",
	param9_desc = "This is the value passed to the function as 9. parameter.",
}

-- TODO: actually implement these as examples
yl_speak_up.custom_functions_p_[ "set_variable_to_random_number" ] = {
	function_call = "yl_speak_up.set_variable_to_random_number",
	description = "Set a variable to a random number.",
	param1_text = "Name of the variable:",
	param1_desc = "Which variable do you want to set to a random number?",
	param2_text = "Minimum value:",
	param2_desc = "Which is the MINIMUM value the varible might be set to?",
	param3_text = "Maximum value:",
	param3_desc = "Which is the MAXIMUM value the varible might be set to?",
}

yl_speak_up.custom_functions_p_[ "set_variable_to_random_value_from_list" ] = {
	function_call = "yl_speak_up.select_random_value_from_list",
	description = "Set a variable to a random value from a list.",
	param1_text = "Name of the variable:",
	param1_desc = "Which variable do you want to set to a random value from your list?",
	param2_text = "Possible values:",
	param2_desc = "Enter all the possible values/texts for your variable here.\n"..
			"Seperate the entires by \"|\", i.e.: \"entry1|entry2|entry3\".",
}


yl_speak_up.custom_functions_p_[ "get_level_of_player" ] = {
	function_call = "yl_speak_up.get_player_level",
	description = "Get the level the player has achieved.",
}


-- example function for results/effects:
yl_speak_up.custom_functions_r_[ "example function" ] = {
	function_call = "yl_speak_up.custom_example_function",
	description = "Describe here in short form what your function does.",
	description = "This function is just an example. It does nothing.",
	param1_text = "1. Parameter:",
	param1_desc = "This is the value passed to the function as first parameter.",
	param2_text = "2. Parameter:",
	param2_desc = "This is the value passed to the function as second parameter.",
	param3_text = "3. Parameter:",
	param3_desc = "This is the value passed to the function as 3. parameter.",
	param4_text = "4. Parameter:",
	param4_desc = "This is the value passed to the function as 4. parameter.",
	param5_text = "5. Parameter:",
	param5_desc = "This is the value passed to the function as 5. parameter.",
	param6_text = "6. Parameter:",
	param6_desc = "This is the value passed to the function as 6. parameter.",
	param7_text = "7. Parameter:",
	param7_desc = "This is the value passed to the function as 7. parameter.",
	param8_text = "8. Parameter:",
	param8_desc = "This is the value passed to the function as 8. parameter.",
	param9_text = "9. Parameter:",
	param9_desc = "This is the value passed to the function as 9. parameter.",
}