-- power/network.lua

local me = microexpansion

---
--- Helper Functions
---

-- [local function] Renumber table
local function renumber_table(t)
		local result = {}
		for _, value in pairs(t) do
				result[#result+1] = value
		end
		return result
end

-- [local function] Get netitem by position
local function get_netitem_by_pos(list, pos)
	for _, i in pairs(list) do
		if vector.equals(pos, i.pos) then
			return i
		end
	end
end

---
--- API Functions
---

-- [function] Get node
function me.get_node(pos)
	local node = minetest.get_node_or_nil(pos)
	if node then return node end
	local vm = VoxelManip()
	local MinEdge, MaxEdge = vm:read_from_map(pos, pos)
	return minetest.get_node(pos)
end

-- [function] Generate new network ID
function power.new_id()
	local count = 1
	for _, i in pairs(me.networks) do
		count = count + 1
	end

	return "network_"..count
end

-- [function] Can connect
function power.can_connect(pos)
	local node = me.get_node(pos)
	local res  = minetest.get_item_group(node.name, "me_connect")

	if res == 1 then
		return true
	else
		return false
	end
end

-- [function] Get connected nodes
function power.get_connected_nodes(pos, include_ctrl)
	local nodes = {
			{x=pos.x+1, y=pos.y,   z=pos.z},
			{x=pos.x-1, y=pos.y,   z=pos.z},
			{x=pos.x,   y=pos.y+1, z=pos.z},
			{x=pos.x,   y=pos.y-1, z=pos.z},
			{x=pos.x,   y=pos.y,   z=pos.z+1},
			{x=pos.x,   y=pos.y,   z=pos.z-1},
		}

	for _, pos in pairs(nodes) do
		if not power.can_connect(pos) then
			nodes[_] = nil
		else
			if include_ctrl == false then
				if me.get_node(pos).name == "microexpansion:ctrl" then
					nodes[_] = nil
				end
			end
		end
	end

	return renumber_table(nodes)
end

-- [function] Add machine to network
function power.add_machine(pos, def)
	
end

-- [function] Remove machine from network
function power.remove_machine(pos)
	local meta = minetest.get_meta(pos)
	meta:set_string("network_ignore", "true")
end

-- [function] Trace network
function power.trace(pos)
	local netpos = me.networks[minetest.get_meta(pos):get_string("network_id")]

	-- if no network, return
	if not netpos then
		return
	end

	local meta  = minetest.get_meta(netpos)
	local netid = meta:get_string("network_id")
	local list  = {}
	local demand

	local delete = false
	if meta:get_string("network_ignore") == "true" then
		delete = true
	end

	-- [local function] Indexed
	local function indexed(pos)
		for _, i in pairs(list) do
			if vector.equals(pos, i.pos) then
				return true
			end
		end
	end

	-- [local function] Trace
	local function trace(nodes)
		for _, pos in pairs(nodes) do
			if not indexed(pos) then
				local machine = minetest.get_meta(pos)
				if machine:get_string("network_ignore") ~= "true" then
					local node = me.get_node(pos).name
					local desc = minetest.registered_nodes[node].description
					if delete then
						machine:set_string("network_id", nil)
						machine:set_string("infotext", desc.."\nNo Network")
						me.network_set_demand(pos, 0)
					else
						machine:set_string("network_id", netid)
						machine:set_string("infotext", desc.."\nNetwork ID: "..netid)
					end

					list[#list + 1] = { pos = pos, demand = machine:get_int("demand") }
					trace(power.get_connected_nodes(pos, false))
				end
			end
		end
	end

	trace(power.get_connected_nodes(netpos))

	-- Check original list
	local original = minetest.deserialize(meta:get_string("netitems"))
	if original then
		for _, i in pairs(original) do
			if not indexed(i.pos) then
				local node = me.get_node(i.pos).name
				local desc = minetest.registered_nodes[node].description
				local machine = minetest.get_meta(i.pos)
				machine:set_string("network_id", nil)
				machine:set_string("infotext", desc.."\nNo Network")
				me.network_set_demand(pos, 0)
			end
		end
	end

	meta:set_string("netitems", minetest.serialize(list))

	-- Update infotext
	meta:set_string("infotext", "Network Controller (owned by "..
		meta:get_string("owner")..")\nNetwork ID: "..meta:get_string("network_id")..
		"\nDemand: "..dump(me.network_get_demand(netpos)))
end

---
--- Load Management
---

-- [function] Get load information
function me.network_get_load(pos)
	local ctrl = me.networks[minetest.get_meta(pos):get_string("network_id")]
	if ctrl then
		local meta = minetest.get_meta(ctrl)
		local list = minetest.deserialize(meta:get_string("netitems"))
	end
end

---- Generators ----

---- Output ----

-- [function] Get total network demand
function me.network_get_demand(pos)
	local ctrl = me.networks[minetest.get_meta(pos):get_string("network_id")]

	-- if no network, return
	if not ctrl then
		return
	end

	local meta = minetest.get_meta(ctrl)
	local list = minetest.deserialize(meta:get_string("netitems"))

	local demand = 0
	for _, i in pairs(list) do
		if i.demand then
			demand = demand + i.demand
		end
	end

	return demand
end

-- [function] Set demand for machine
function me.network_set_demand(pos, demand)
	-- Update original metadata
	minetest.get_meta(pos):set_int("demand", demand)

	local ctrl = me.networks[minetest.get_meta(pos):get_string("network_id")]

	-- if no network, return
	if not ctrl then
		return
	end

	local meta = minetest.get_meta(ctrl)
	local list = minetest.deserialize(meta:get_string("netitems"))
	local item = get_netitem_by_pos(list, pos)

	if not item then
		return
	end

	item.demand = demand
	meta:set_string("netitems", minetest.serialize(list))

	-- Update infotext
	meta:set_string("infotext", "Network Controller (owned by "..
		meta:get_string("owner")..")\nNetwork ID: "..meta:get_string("network_id")..
		"\nDemand: "..dump(me.network_get_demand(pos)))
end

---- Storage ----