local NAME = minetest.get_current_modname()
local ENERGYCOST  = {
	static_strut = 20,
	dynamic_struct = 24,
	hardness_mod = 1,
	mining = 25,
}
local MAX_ENERGY = 3000
local FORMSPEC = sparktech.add_inventory(19.8,8,
	"list[current_name;quarry;0,0;16,6;]")
local MAX_SIZE = 64

local function Position(x, y, z) ---
	--- Returns a valid pos as used by the game
	return {x=x, y=y, z=z}
end

local function try_drain_energy(target_pos, amount) ---
	--- Returns true if drained, false otherwise
	--- Removes amount energy from target_pos if energy >= amount
	local target = minetest.get_meta(target_pos)
	local current = target:get_int("energy")
	if current >= amount then
		target:set_int("energy", current - amount)
		return true
	else
		return false
	end
end

local function try_remove_item(target_pos, listname, itemname, amount)
	local inv = minetest.get_inventory({type="node", pos=target_pos})
	local stack = ItemStack(itemname)
	local amount = amount or 1
	stack:set_count(amount)

	local result = inv:remove_item(listname, stack)

	if result:get_count() ~= amount then
		inv:add_item(listname, result)
	else
		return true
	end
	
	return false
end

local function on_construct(pos, player)
	player:get_meta():set_string(NAME .. ":quarry_pos" , minetest.pos_to_string(pos))

	local meta = minetest.get_meta(pos)
	meta:set_string("formspec", FORMSPEC)
	local inventory = meta:get_inventory()
	inventory:set_size('quarry', 96)
end

local function dig_node(pos, quarrypos)
	local node = minetest.get_node(pos)

	if node.name ~= "air" and sparktech.drain_energy(quarrypos, ENERGYCOST.mining) then

		local quarry = minetest.get_meta(quarrypos)
		local quarry_inv = quarry:get_inventory()

		sparktech.dig_node(pos, quarry_inv, "quarry", nil)
	end

	return node.name ~= "air"
end

local function on_marker_placed(pos, quarry_pos, player)
	-- Validate position
	if quarry_pos.x == pos.x and
	   quarry_pos.y == pos.y and
	   quarry_pos.z == pos.z then
		-- Invalid position, marker replaced quarry somehow
		return -- TODO Report failure?
		-- TODO clear clipboard in quarry on_break

	end

	local minx, maxx = math.order(pos.x, quarry_pos.x)
	local miny, maxy = math.order(pos.y, quarry_pos.y)
	local minz, maxz = math.order(pos.z, quarry_pos.z)

	local diffx = maxx - minx
	local diffy = maxy - miny
	local diffz = maxz - minz

	if diffx < 2 or diffx >= MAX_SIZE or
	   diffy < 2 or diffy >= MAX_SIZE or
	   diffz < 2 or diffz >= MAX_SIZE
	then
		notify.hud.sendtext(player, "Invalid dimensions for quarry 3x3x3")
		return
	end

	-- Set quarry metadata
	local meta = minetest.get_meta(quarry_pos)
	meta:set_string("marker", minetest.pos_to_string(pos))
	meta:set_int("current_frame", 1)

	minetest.get_node_timer(quarry_pos):start(1.0)
end

local function marker_construct(pos, player)
	local quarry_pos = minetest.string_to_pos(player:get_meta():get_string(NAME .. ":quarry_pos"))
	local quarry = minetest.get_node(quarry_pos)		
	on_marker_placed(pos, quarry_pos, player)	
end

local function place_strut(position, quarrypos)
	if minetest.get_node(position).name == "air" then
		local placed = false
		if try_drain_energy(quarrypos, ENERGYCOST.static_strut) then
			if try_remove_item(quarrypos, "quarry", NAME .. ":static_strut") then
				minetest.set_node(position, { name = NAME .. ":static_strut"})
				placed = true
			end
		end
		return true, placed
	end
	return false, false
end

local function prepare_area(pos, pos2)
	local placement_done = true
	local minx, maxx = math.order(pos.x, pos2.x)
	local miny, maxy = math.order(pos.y, pos2.y)
	local minz, maxz = math.order(pos.z, pos2.z)
	for x=minx , maxx do
		for y=miny, maxy do
			for z=minz, maxz do
				-- dont remove quarry or marker
				if not (x == pos.x and y == pos.y and z == pos.z) then
					local count = 0
					if x == pos.x then count = count +1 end
					if x == pos2.x then count = count +1 end
					if y == pos.y then count = count +1 end
					if y == pos2.y then count = count +1 end
					if z == pos.z then count = count +1 end
					if z == pos2.z then count = count +1 end
					if count >= 2 then
						local node = minetest.get_node(Position(x, y, z))
						if node.name ~= NAME .. ":static_strut" then
							if node.name ~= "air" then
								dig_node(Position(x, y, z), pos)
								return false
							end
							local incomplete, placed = place_strut(Position(x, y, z), pos)
							if placed then
								return false
							end

							if incomplete then
								placement_done = false
							end
						end
					else
						if dig_node(Position(x, y, z), pos) then
							return false
						end
					end
				end
			end
		end
	end
	return placement_done --true: cleared
end


local function timer_trigger(pos, elapsed)
	local meta = minetest.get_meta(pos)
	if not meta then assert("FUCK") end
	local framenum = meta:get_int("current_frame")
	local marker_pos = minetest.string_to_pos(meta:get_string("marker"))

	while true do -- Make this section breakable
		if framenum < 0 then
			-- Operation Phase
			--
			local start_pos = minetest.string_to_pos(meta:get_string("dig_area_start"))
			local end_pos = minetest.string_to_pos(meta:get_string("dig_area_end"))
			if not start_pos or not end_pos then return end
			local height = start_pos.y + framenum

			local exitloop = false
			for x=start_pos.x, end_pos.x do
				for z=start_pos.z, end_pos.z do
					if dig_node(Position(x, height, z), pos) then
						exitloop = true
					end
					if exitloop then break end
				end
				if exitloop then break end
			end
			if not exitloop then
				-- Layer cleared, next layer
				framenum = framenum - 1
			end
		elseif framenum == 1 then
			-- preparation phase
			if prepare_area(pos, marker_pos) then
				framenum = 0
			end
		else
			--shrink the operational area here to a 2d space with one piece of border taken away to drill there
			--
			local posx, pos2x = math.order(pos.x, marker_pos.x)
			local posy, pos2y = math.order(pos.y, marker_pos.y)
			local posz, pos2z = math.order(pos.z, marker_pos.z)
			posx = posx +1
			pos2x = pos2x -1
			posz = posz + 1
			pos2z = pos2z -1
			meta:set_string("dig_area_start", minetest.pos_to_string(Position(posx, posy, posz)))
			meta:set_string("dig_area_end", minetest.pos_to_string(Position(pos2x, posy, pos2z))) -- can use this last z as counter, or ignore it
			framenum = -1
		end

		break
	end

	meta:set_int("current_frame", framenum)
	
	if framenum >= -MAX_SIZE then minetest.get_node_timer(pos):start(0.1) end
end

minetest.register_node( NAME .. ":quarry_marker", {
	descritption = "quarry marker",
	tiles = {
		NAME .. "marker.png"
	},
	groups = { sparktech_techy = 1 },
	after_place_node = marker_construct,
})

minetest.register_node( NAME .. ":static_strut", {
	description = "supporting strut",
	drawtype = "nodebox",
	paramtype = "light",
	connects_to = {
		NAME .. ":static_strut",
		NAME .. ":quarry_marker",
		NAME .. ":lv_quarry"
	},
	tiles = {
		NAME .. "_strut.png"
	},
	node_box = {
		type = "connected",
		fixed = {-0.2, -0.2, -0.2, 0.2, 0.2, 0.2},
		connect_top = {-0.2, 0.2, -0.2, 0.2, 0.5, 0.2},
		connect_bottom = {-0.2, -0.5, -0.2, 0.2, -0.2, 0.2},
		connect_back = {-0.2, -0.2, 0.2, 0.2, 0.2, 0.5},
		connect_right = {0.2, -0.2, -0.2, 0.5, 0.2, 0.2},
		connect_front = {-0.2, -0.2, -0.5, 0.2, 0.2, -0.2},
		connect_left = {-0.5, -0.2, -0.2, -0.2, 0.2, 0.2},
	},
	groups = { sparktech_techy = 1 }
})

minetest.register_node( NAME .. ":lv_quarry", {
	description = "Electric Quarry",

	tiles = {
		NAME .. "_steel_sideplate.png",
		NAME .. "_steel_sideplate.png",
		NAME .. "_steel_sideplate.png",
		NAME .. "_steel_sideplate.png",
		NAME .. "_steel_backplate.png",
		NAME .. "_quarry_frontplate.png"
	},
	paramtype2 = "facedir",

	groups = {
		sparktech_techy = WRENCHABLE,
		sparktech_energy_type = ENERGY_CONSUMER,
		sparktech_net_trigger = TRUE,
		sparktech_energy_max = MAX_ENERGY,
		sparktech_energy_wakeup = ENERGYCOST.mining
	},

	on_timer = timer_trigger,

	after_place_node = on_construct,

	--on_destruct = function(pos, player) player:get_meta():set_string(NAME .. ":quarry_pos" , "") end,
	allow_metadata_inventory_put = function(_,_,_, stack) return stack:get_count() end,
	allow_metadata_inventory_take = function(_, _, _, stack) return stack:get_count() end
})
minetest.register_craft({
	output = NAME .. ":lv_quarry",
	recipe = {
		{ NAME .. ":static_strut", "sparktool:handdrill", NAME .. ":static_strut" },
		{ NAME .. ":static_strut", "group:steel_chasis", NAME .. ":static_strut" },
		{ NAME .. ":static_strut", "sparkcore:cable", NAME .. ":static_strut" }
	}
})


minetest.register_craft({
	output = NAME .. ":static_strut 16",
	recipe = {
		{ "group:steel_plate", "group:steel_plate", "group:steel_plate" },
		{ "", "", "" },
		{ "group:steel_plate", "group:steel_plate", "group:steel_plate" }
	}
})