-- string
function string:split(inSplitPattern, outResults)
	if not outResults then
		outResults = {}
	end
	local theStart = 1
	local theSplitStart, theSplitEnd = string.find( self, inSplitPattern, theStart )
	while theSplitStart do
		table.insert( outResults, string.sub( self, theStart, theSplitStart-1 ) )
		theStart = theSplitEnd + 1
		theSplitStart, theSplitEnd = string.find( self, inSplitPattern, theStart )
	end
	table.insert( outResults, string.sub( self, theStart ) )
	return outResults
end

-- form

story.talk_form = "size[8,7.5;]"
story.talk_form = story.talk_form..default.gui_colors
story.talk_form = story.talk_form..default.gui_bg
story.talk_form = story.talk_form.."image[0,0.0;3,8;story_player.png]"
story.talk_form = story.talk_form.."label[2.5,0;%s]"
story.talk_form = story.talk_form.."image[6,0.0;3,8;story_character_1.png]"

story.get_talk_form = function(text)
	return string.format(story.talk_form, text)
end

-- hud

story.hud = {}

minetest.register_on_joinplayer(function(player)
	if story.generator.players_storys[player:get_player_name()] and story.generator.players_storys[player:get_player_name()].pos then
		story.hud[player:get_player_name()] = player:hud_add({
			hud_elem_type = "waypoint",
			name = "story",
			text = "",
			number = 0x00FF00,
			world_pos = story.generator.players_storys[player:get_player_name()].pos
		})
	end

	story.hud[player:get_player_name()] = player:hud_add({
		hud_elem_type = "waypoint",
		name = "story",
		text = "",
		number = 0x00FF00,
		world_pos = {x=0,y=0,z=0}
	})
end)

-- generator

story.generator = {}
story.generator.parts = {}
story.generator.dialogs = {}	
story.generator.players_storys = {}

function story.generator.gen_next_step(player)
	print("[INFO] generating story...")
	if not story.generator.players_storys[player:get_player_name()] then
		print("[ERROR][story] could not find players story")
		return
	end
	
	local part = story.generator.get_part(story.generator.players_storys[player:get_player_name()].part)
	if part then
		story.generator.players_storys[player:get_player_name()].part = story.generator.run(part, player)
		return
	else
		print("[ERROR][story] could not find part file")
		return
	end
end

function story.generator.new_player(player)
	-- adds a new entry to the story database
	story.generator.players_storys[player:get_player_name()] = {}
	story.generator.players_storys[player:get_player_name()].part = "base"
end

function story.generator.get_part(name)
	if not name then return end
	if name == "" then return end
	if not story.generator.parts[name] then
		local file = io.open(minetest.get_modpath("story").."/parts/"..name..".part", "r")
		story.generator.parts[name] = file:read("*all")
		io.close(file)
		return story.generator.parts[name]
	else
		return story.generator.parts[name]
	end
end

function story.generator.get_dialog(name)
	if not story.generator.dialogs[name] then
		local file = io.open(minetest.get_modpath("story").."/parts/"..name..".dialog", "r")
		story.generator.dialogs[name] = file:read("*all")
		io.close(file)
		return story.generator.dialogs[name]
	else
		return story.generator.dialogs[name]
	end
end

function story.generator.run(part, player)
	local next_part = ""
	print("[INFO] run script... " .. part)
	local lines = part:split("\n")
	if not lines then 
		return ""
	end	
	for k,v in pairs(lines) do
		local cmd = v:split(" ")
		if cmd[1] then
			print("[INFO] run line... " .. v)
			if cmd[1] == "$dialog" and cmd[2] then
				if story.generator.get_dialog(cmd[2]) then
					story.generator.players_storys[player:get_player_name()].text = story.generator.get_dialog(cmd[2])	
				end
			end
			if cmd[1] == "$create" then
				story.generator.show(player, {x=0, y=10, z=0})
			end
			-- test cmd
			if cmd[1] == "$pos" then
				story.generator.players_storys[player:get_player_name()].pos = {x=0, y=10, z=0}
			end
		end
	end
	return next_part
end

function story.generator.show(player, p)
	-- update waypoint
	player:hud_remove(story.hud[player:get_player_name()])
	story.hud[player:get_player_name()] = player:hud_add({
		hud_elem_type = "waypoint",
		name = "story",
		text = "",
		number = 0x00FF00,
		world_pos = p
	})

	minetest.add_entity(p, "story:human")
end

minetest.register_on_newplayer(function(player)
	story.generator.new_player(player)
	story.generator.gen_next_step(player)
end)

-- human
minetest.register_entity("story:human", {
	hp_max = 50,
	physical = true,
	collisionbox = {-0.4,-1,-0.4, 0.4,1,0.4},
 	visual = "mesh",
 	visual_size = {x=1, y=1},
	textures = {"character.png",},
	mesh = "character.x",
	spritediv = {x=1, y=1},
	initial_sprite_basepos = {x=0, y=0},	
	is_visible = true,
	makes_footstep_sound = false,
	automatic_rotate = true,
	speed = 0,
	plname = nil,
	text = nil,

	on_rightclick = function(self, clicker)
		if not clicker or not clicker:is_player() then
			return
		end
		if not story.generator.players_storys[clicker:get_player_name()] then
			return
		end
		-- shows the dialog
		if story.generator.players_storys[clicker:get_player_name()].pos then
			if vector.distance(self.object:getpos(), story.generator.players_storys[clicker:get_player_name()].pos) < 3 then
				minetest.show_formspec(clicker:get_player_name(), "story:story", story.get_talk_form(story.generator.players_storys[clicker:get_player_name()].text))
				story.generator.gen_next_step(clicker)	
				-- TODO : delete npc after talking with it (or move it some where else)	
			end
		end
	end,

	on_step = function(self, dtime)
		-- nothing
	end,
})

minetest.register_craftitem("story:human", {
	description = "Human",
	inventory_image = "story_character_spawn.png",

	on_place = function(itemstack, placer, pointed_thing)
		if pointed_thing.type ~= "node" then
			return
		end
		local p = pointed_thing.above
		p.y = p.y + 0.5
		minetest.add_entity(p, "story:human")
		if not minetest.setting_getbool("creative_mode") then
			itemstack:take_item()
		end
		return itemstack
	end,
})