--[[

	TechAge
	=======

	Copyright (C) 2019 Joachim Stolberg

	LGPLv2.1+
	See LICENSE.txt for more information
	
	TA3 Power Station Generator

]]--

-- for lazy programmers
local S = function(pos) if pos then return minetest.pos_to_string(pos) end end
local P = minetest.string_to_pos
local M = minetest.get_meta

-- Load support for intllib.
local MP = minetest.get_modpath("techage")
local I,_ = dofile(MP.."/intllib.lua")

local STANDBY_TICKS = 4
local COUNTDOWN_TICKS = 4
local CYCLE_TIME = 8
local POWER_CAPACITY = 75

local Cable = techage.ElectricCable

local function formspec(self, pos, mem)
	return "size[8,7]"..
		default.gui_bg..
		default.gui_bg_img..
		default.gui_slots..
		"image[6,0.5;1,2;"..techage.power.formspec_power_bar(POWER_CAPACITY, mem.power_result).."]"..
		"image_button[5,1;1,1;".. self:get_state_button_image(mem) ..";state_button;]"..
		"button[2,1.5;2,1;update;"..I("Update").."]"..
		"list[current_player;main;0,3;8,4;]"..
		default.get_hotbar_bg(0, 3)
end

local function turbine_running(pos)
	local pos1 = techage.get_pos(pos, 'L')
	local node = minetest.get_node(pos1)
	return node.name == "techage:turbine_on"
end

local function start_node(pos, mem, state)
	techage.power.power_distribution(pos)
end

local function stop_node(pos, mem, state)
	techage.power.power_distribution(pos)
end

local State = techage.NodeStates:new({
	node_name_passive = "techage:generator",
	node_name_active = "techage:generator_on",
	cycle_time = CYCLE_TIME,
	standby_ticks = STANDBY_TICKS,
	formspec_func = formspec,
	can_start = turbine_running,
	start_node = start_node,
	stop_node = stop_node,
})

-- Pass1: Power balance calculation
local function on_power_pass1(pos, mem)
	if State:is_active(mem) then
		return -POWER_CAPACITY
	end
	return 0
end	
		
-- Pass2: Power balance adjustment
local function on_power_pass2(pos, mem, sum)
	return 0
end

-- Pass3: Power balance result
local function on_power_pass3(pos, mem, sum)
	mem.power_result = sum
end

local function distibuting(pos, mem)
	if mem.power_result > 0 then
		State:keep_running(pos, mem, COUNTDOWN_TICKS)
	else
		State:fault(pos, mem)	
		techage.power.power_distribution(pos)
	end
end

local function node_timer(pos, elapsed)
	local mem = tubelib2.get_mem(pos)
	if turbine_running(pos) then
		distibuting(pos, mem)
	else
		State:fault(pos, mem)	
		techage.power.power_distribution(pos)
	end
	return State:is_active(mem)
end

local function on_receive_fields(pos, formname, fields, player)
	if minetest.is_protected(pos, player:get_player_name()) then
		return
	end
	local mem = tubelib2.get_mem(pos)
	State:state_button_event(pos, mem, fields)
	
	if fields.update then
		M(pos):set_string("formspec", formspec(State, pos, mem))
	end
end

local function on_rightclick(pos)
	local mem = tubelib2.get_mem(pos)
	M(pos):set_string("formspec", formspec(State, pos, mem))
end

minetest.register_node("techage:generator", {
	description = I("TA3 Generator"),
	tiles = {
		-- up, down, right, left, back, front
		"techage_filling_ta3.png^techage_frame_ta3.png",
		"techage_filling_ta3.png^techage_frame_ta3.png",
		"techage_filling_ta3.png^techage_appl_hole_electric.png^techage_frame_ta3.png",
		"techage_filling_ta3.png^techage_appl_open.png^techage_frame_ta3.png",
		"techage_filling_ta3.png^techage_frame_ta3.png^techage_appl_generator.png",
		"techage_filling_ta3.png^techage_frame_ta3.png^techage_appl_generator.png^[transformFX]",
	},
	
	on_construct = tubelib2.init_mem,
	
	after_place_node = function(pos, placer)
		local mem = tubelib2.get_mem(pos)
		State:node_init(pos, mem, "")
		on_rightclick(pos)
	end,

	after_dig_node = function(pos, oldnode, oldmetadata, digger)
		State:after_dig_node(pos, oldnode, oldmetadata, digger)
	end,
	
	on_receive_fields = on_receive_fields,
	on_rightclick = on_rightclick,
	on_timer = node_timer,

	drop = "",
	paramtype2 = "facedir",
	groups = {cracky=2, crumbly=2, choppy=2},
	on_rotate = screwdriver.disallow,
	is_ground_content = false,
	sounds = default.node_sound_wood_defaults(),
})

minetest.register_node("techage:generator_on", {
	description = I("TA3 Generator"),
	tiles = {
		-- up, down, right, left, back, front
		"techage_filling_ta3.png^techage_frame_ta3.png",
		"techage_filling_ta3.png^techage_frame_ta3.png",
		"techage_filling_ta3.png^techage_appl_hole_electric.png^techage_frame_ta3.png",
		"techage_filling_ta3.png^techage_appl_open.png^techage_frame_ta3.png",
		{
			image = "techage_filling4_ta3.png^techage_appl_generator4.png^techage_frame4_ta3.png",
			backface_culling = false,
			animation = {
				type = "vertical_frames",
				aspect_w = 32,
				aspect_h = 32,
				length = 0.3,
			},
		},
		{
			image = "techage_filling4_ta3.png^techage_appl_generator4.png^techage_frame4_ta3.png",
			backface_culling = false,
			animation = {
				type = "vertical_frames",
				aspect_w = 32,
				aspect_h = 32,
				length = 0.3,
			},
		},
	},
	
	on_receive_fields = on_receive_fields,
	on_rightclick = on_rightclick,
	on_timer = node_timer,

	drop = "",
	paramtype2 = "facedir",
	groups = {not_in_creative_inventory=1},
	diggable = false,
	on_rotate = screwdriver.disallow,
	is_ground_content = false,
	sounds = default.node_sound_wood_defaults(),
})

minetest.register_craft({
	output = "techage:generator",
	recipe = {
		{"basic_materials:steel_bar", "dye:green", "default:wood"},
		{"", "basic_materials:gear_steel", "techage:electric_cableS"},
		{"default:wood", "techage:iron_ingot", "basic_materials:steel_bar"},
	},
})

techage.power.register_node({"techage:generator", "techage:generator_on"}, {
	on_power_pass1 = on_power_pass1,
	on_power_pass2 = on_power_pass2,
	on_power_pass3 = on_power_pass3,
	conn_sides = {"R"},
	power_network = Cable,
})

techage.register_help_page(I("TA3 Generator"), 
I([[Part of the Coal Power Station.
Has to be placed side by side
with the TA3 Turbine.
Connect the Generator with your TA3 machines
by means of Electric Cables and Junction Boxes
(see TA3 Coal Power Station)]]), "techage:generator")