-- MinecartTracks
-- by Revolucas


local PLUGIN_NAME = "MinecartTracks"
local PLUGIN_VERSION = 1

--BlockMetas for Minecart tracks which are compatible to visually join
local CompatibleMetas = { 		[0] = {0,4,5,6,7,8,9},
								[1] = {1,2,3,6,7,8,9},
								[2] = {1,2,3,7,8},
								[3] = {1,2,3,6,9},
								[4] = {0,4,5,6,7},
								[5] = {0,4,5,8,9},
								[6] = {0,1,2,3,4,5,6,7,8,9},
								[7] = {0,1,2,3,4,5,6,7,8,9},
								[8] = {0,1,2,3,4,5,6,7,8,9},
								[9] = {0,1,2,3,4,5,6,7,8,9}}
--Positions to check for tracks according to block meta
local CompatibleDirections = {
								[0] = { {0,0,1} ,{0,0,-1},{0,1,1} ,{0,-1,1} ,{0,1,-1},{0,-1,-1}},
								[1] = { {1,0,0} ,{-1,0,0},{1,1,0} ,{1,-1,0} ,{-1,1,0},{-1,-1,0}},
								[2] = { {-1,0,0},{-1,1,0},{1,1,0} ,{-1,-1,0} },
								[3] = { {1,0,0} ,{1,1,0} ,{-1,1,0},{-1,-1,0} },
								[4] = { {0,0,1} ,{0,-1,1},{0,1,-1},{0,1,1} },
								[5] = { {0,0,-1},{0,-1,-1},{0,1,1},{0,1,-1} },
								[6] = { {1,0,0} ,{0,0,1} ,{1,1,0} ,{1,-1,0} ,{0,1,1},{0,-1,1} },
								[7] = { {-1,0,0},{0,0,1} ,{-1,1,0},{-1,-1,0},{0,1,1},{0,-1,1}},
								[8] = { {-1,0,0},{0,0,-1},{-1,1,0},{-1,-1,0},{0,1,-1},{0,-1,-1}},
								[9] = { {1,0,0} ,{1,1,0} ,{1,-1,0},{0,0,-1} ,{0,1,-1},{0,-1,-1}}}




--Definitions of behavior for Relative Positions to placed track
--           [-1,0,0]
--    [0,0,1][0,0,0 ][0,0,-1]
--           [1,0,0 ]
local DefineTrackBehavior = {
	["1,0,0"]  = {	["0,0,1"]  = {9,1},["0,0,-1"] = {6,1},["-1,0,0"] = {1,1}, ["1,0,0"] = {1,1},
					["0,1,1"]  = {9,1},["0,1,-1"] = {6,1},["-1,1,0"] = {1,1}, ["1,1,0"] = {1,1},
					["0,-1,1"] = {9,1},["0,-1,-1"]= {6,1},["-1,-1,0"]= {1,1}, ["1,-1,0"]= {3,1}},
	["1,1,0"]  = {	["0,0,1"]  = {9,2},["0,0,-1"] = {6,2},["-1,0,0"] = {1,1}, ["1,0,0"] = {2,1},
					["0,1,1"]  = {9,2},["0,1,-1"] = {6,2},["-1,1,0"] = {2,1}, ["1,1,0"] = {2,1},
					["0,-1,1"] = {9,2},["0,-1,-1"]= {6,2},["-1,-1,0"]= {2,1}, ["1,-1,0"]= {2,1}},
	["1,-1,0"] = {	["0,0,1"]  = {9,3},["0,0,-1"] = {6,3},["-1,0,0"] = {1,3}, ["1,0,0"] = {1,3},
					["0,1,1"]  = {9,3},["0,1,-1"] = {6,3},["-1,1,0"] = {1,3}, ["1,1,0"] = {1,3},
					["0,-1,1"] = {9,3},["0,-1,-1"]= {6,3},["-1,-1,0"]= {1,3}, ["1,-1,0"]= {3,3}},

	["0,0,1"]  = {	["1,0,0"]  = {7,0},["-1,0,0"] = {6,0},["0,0,1"]  = {0,0}, ["0,0,-1"] = {0,0},
					["1,1,0"]  = {7,0},["-1,1,0"] = {6,0},["0,1,1"]  = {0,0}, ["0,1,-1"] = {0,0},
					["1,-1,0"] = {7,0},["-1,-1,0"]= {6,0},["0,-1,1"] = {4,0}, ["0,-1,-1"]= {4,0}},
	["0,1,1"]  = {	["1,0,0"]  = {7,5},["-1,0,0"] = {6,5},["0,0,1"]  = {5,0}, ["0,0,-1"] = {0,0},
					["1,1,0"]  = {7,5},["-1,1,0"] = {6,5},["0,1,1"]  = {5,0}, ["0,1,-1"] = {5,0},
					["1,-1,0"] = {7,5},["-1,-1,0"]= {6,5},["0,-1,1"] = {5,0}, ["0,-1,-1"]= {5,0}},
	["0,-1,1"] = {	["1,0,0"]  = {7,4},["-1,0,0"] = {6,4},["0,0,1"]  = {0,4}, ["0,0,-1"] = {0,4},
					["1,1,0"]  = {7,4},["-1,1,0"] = {6,4},["0,1,1"]  = {0,4}, ["0,1,-1"] = {0,4},
					["1,-1,0"] = {7,4},["-1,-1,0"]= {6,4},["0,-1,1"] = {4,4}, ["0,-1,-1"]= {4,4}},

	["-1,0,0"] = {	["0,0,-1"] = {7,1},["0,0,1"]  = {8,1},["1,0,0"]  = {1,1}, ["-1,0,0"] = {1,1},
					["0,1,-1"] = {7,1},["0,1,1"]  = {8,1},["1,1,0"]  = {1,1}, ["-1,1,0"] = {1,1},
					["0,-1,-1"]= {7,1},["0,-1,1"] = {8,1},["1,-1,0"] = {1,1}, ["-1,-1,0"]= {2,1}},
	["-1,1,0"] = {	["0,0,-1"] = {7,3},["0,0,1"]  = {8,3},["1,0,0"]  = {1,3}, ["-1,0,0"] = {1,3},
					["0,1,-1"] = {7,3},["0,1,1"]  = {8,3},["1,1,0"]  = {3,1}, ["-1,1,0"] = {3,1},
					["0,-1,-1"]= {7,3},["0,-1,1"] = {8,3},["1,-1,0"] = {3,1}, ["-1,-1,0"]= {3,1}},
	["-1,-1,0"]= {	["0,0,-1"] = {7,2},["0,0,1"]  = {8,2},["1,0,0"]  = {1,2}, ["-1,0,0"] = {1,2},
					["0,1,-1"] = {7,2},["0,1,1"]  = {8,2},["1,1,0"]  = {1,2}, ["-1,1,0"] = {1,2},
					["0,-1,-1"]= {7,2},["0,-1,1"] = {8,2},["1,-1,0"] = {1,2}, ["-1,-1,0"]= {2,2}},

	["0,0,-1"] = {	["-1,0,0"] = {9,0},["1,0,0"]  = {8,0},["0,0,1"]  = {0,0}, ["0,0,-1"] = {0,0},
					["-1,1,0"] = {9,0},["1,1,0"]  = {8,0},["0,1,1"]  = {0,0}, ["0,1,-1"] = {0,0},
					["-1,-1,0"]= {9,0},["1,-1,0"] = {8,0},["0,-1,1"] = {5,0}, ["0,-1,-1"]= {5,0}},
	["0,1,-1"] = {	["-1,0,0"] = {9,4},["1,0,0"]  = {8,4},["0,0,1"]  = {0,4}, ["0,0,-1"] = {4,0},
					["-1,1,0"] = {9,4},["1,1,0"]  = {8,4},["0,1,1"]  = {4,0}, ["0,1,-1"] = {4,0},
					["-1,-1,0"]= {9,4},["1,-1,0"] = {8,4},["0,-1,1"] = {4,0}, ["0,-1,-1"]= {4,0}},
	["0,-1,-1"]= {	["-1,0,0"] = {9,5},["1,0,0"]  = {8,5},["0,0,1"]  = {0,5}, ["0,0,-1"] = {0,5},
					["-1,1,0"] = {9,5},["1,1,0"]  = {8,5},["0,1,1"]  = {0,5}, ["0,1,-1"] = {0,5},
					["-1,-1,0"]= {9,5},["1,-1,0"] = {8,5},["0,-1,1"] = {0,5}, ["0,-1,-1"]= {5,5}}}

--When to be placed as a corner piece
local DefineCornerTrack = {
	["1,0,0" ] = { ["0,0,1"]  = 8, 	["0,0,-1"] = 7},
	["0,0,-1"] = { ["-1,0,0"] = 6,  ["1,0,0"]  = 9},
	["-1,0,0"] = { ["0,0,-1"] = 6,	["0,0,1"]  = 9},
	["0,0,1" ] = { ["-1,0,0"] = 8,	["1,0,0"]  = 7}}

--


local MinecartTracksPlugin = {}
MinecartTracksPlugin.__index = MinecartTracksPlugin

function MinecartTracksPlugin:new()
   local t = {}
   setmetatable(t, MinecartTracksPlugin)
   local w = Lua__cPlugin:new()
   tolua.setpeer(w, t)
   w:tolua__set_instance(w)
   return w
end

function MinecartTracksPlugin:OnDisable()
   Log( self:GetName() .. " v." .. self:GetVersion() .. " is shutting down..." )
end

function MinecartTracksPlugin:Initialize()
	self:SetName( PLUGIN_NAME )
	self:SetVersion( PLUGIN_VERSION )

	PluginManager = cRoot:Get():GetPluginManager()
	PluginManager:AddHook( self, cPluginManager.E_PLUGIN_BLOCK_PLACE )
	PluginManager:AddHook( self, cPluginManager.E_PLUGIN_TICK )
	Log( "Initialized " .. self:GetName() .. " v." .. self:GetVersion() )
   return true
end

function IsTrack(BlockID)
	if( BlockID == E_BLOCK_MINECART_TRACKS ) then
		return true
	end
	return false
end

function StringToXYZ(str)
	local pos = {}
	for n in string.gmatch(str,"[^,]+") do
		table.insert(pos,n)
	end
	return tonumber(pos[1]),tonumber(pos[2]),tonumber(pos[3]),tonumber(pos[4])
end

function XYZToString(x,y,z)
	return tostring(x) .. "," ..tostring(y)..","..tostring(z)
end

--local sPlayer --(debug purposes)
--local sServer = cRoot:Get():GetServer() --(debug purposes)
--Searches positions according to meta to see if track is visually connected
function ListConnectedTrack(X,Y,Z,IgnoreX,IgnoreY,IgnoreZ)
	local World = cRoot:Get():GetWorld()
	local Meta = World:GetBlockMeta(X,Y,Z)

	--Loop through tables to find compatible track to connect to
	local ConnectedTrack = {}
	for i,v in ipairs(CompatibleDirections[Meta]) do
			local x = X + v[1]
			local y = Y + v[2]
			local z = Z + v[3]
		if not(x == IgnoreX and y == IgnoreY and z == IgnoreZ) then
			if (IsTrack(World:GetBlock(x,y,z))) then
				local TargetMeta = World:GetBlockMeta(x,y,z)
				for ii,vv in ipairs(CompatibleMetas[Meta]) do
					if (vv == TargetMeta) then
						table.insert(ConnectedTrack,{["X"] = x, ["Y"] = y, ["Z"] = z, ["M"] = TargetMeta})
						break
					end
				end
			end
		end
	end

	return ConnectedTrack
end

--Lists adjacentTrack that is not already connected
function ListAdjacentTrack(X,Y,Z)
	local World = cRoot:Get():GetWorld()
	local AdjacentTracks = {}
	for k,v in pairs(DefineTrackBehavior) do
		-- Grab the relative x,y,z to test for adjacent track
		local x,y,z = StringToXYZ(k)

		x = X-x
		y = Y-y
		z = Z-z
		if (IsTrack(World:GetBlock(x,y,z))) then
			--Check if adjacent track is connected to anything before adding it to list
			local ConnectedTrack = ListConnectedTrack(x,y,z,X,Y,Z)
			if (#ConnectedTrack <= 1) then
				table.insert(AdjacentTracks,{ ["X"] = x, ["Y"] = y, ["Z"] = z, ["M"] = World:GetBlockMeta(x,y,z) })
			end
		end
	end
	return AdjacentTracks
end

function EvaluateConnections(X,Y,Z)
	local World = cRoot:Get():GetWorld()
	local AdjacentTrack = ListAdjacentTrack(X,Y,Z)
	local ConnectedTrack = ListConnectedTrack(X,Y,Z)

	if (#AdjacentTrack == 0) then
		return -- No need to run check
	end

	local CornerMatch
	--See if I can visually join adjacent track
	for i=1, #AdjacentTrack,1 do

		local AdjacentTracksConnections = ListConnectedTrack(AdjacentTrack[i].X,AdjacentTrack[i].Y,AdjacentTrack[i].Z,X,Y,Z)

		for k,v in pairs(DefineTrackBehavior) do
			local RelativeXYZ = tostring(X - AdjacentTrack[i].X) .. "," .. tostring(Y - AdjacentTrack[i].Y) .. "," .. tostring(Z - AdjacentTrack[i].Z)
			if (k == RelativeXYZ and #AdjacentTracksConnections == 0) then
				local AdjConRelXYZ = XYZToString(AdjacentTrack[i].X - X,AdjacentTrack[i].Y - Y,AdjacentTrack[i].Z - Z)

				if (DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][1] ~= -1) then
					World:SetBlockMeta(AdjacentTrack[i].X,AdjacentTrack[i].Y,AdjacentTrack[i].Z,DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][1])
				end
				if (DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][2] ~= -1) then
					World:SetBlockMeta(X,Y,Z,DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][2])
				end
				--sServer:SendMessage( cChatColor.Gold .. AdjConRelXYZ.."|".. XYZToString(X-AdjacentTrack[i].X,Y-AdjacentTrack[i].Y,Z-AdjacentTrack[i].Z) .."[C]=" .. #AdjacentTracksConnections, sPlayer )
			elseif (k == RelativeXYZ and #AdjacentTracksConnections > 0) then
				--Find Adjacent tracks connection's position so we can determine which meta to use
				local AdjConRelXYZ = XYZToString(AdjacentTrack[i].X - AdjacentTracksConnections[1].X,AdjacentTrack[i].Y - AdjacentTracksConnections[1].Y,AdjacentTrack[i].Z - AdjacentTracksConnections[1].Z)
				if (DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ]) then
					if (DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][1] ~= -1) then
						World:SetBlockMeta(AdjacentTrack[i].X,AdjacentTrack[i].Y,AdjacentTrack[i].Z,DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][1])
					end
					if (DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][2] ~= -1) then
						World:SetBlockMeta(X,Y,Z,DefineTrackBehavior[RelativeXYZ][AdjConRelXYZ][2])
					end
				end
				--sServer:SendMessage( cChatColor.Gold .. AdjConRelXYZ .. "|" ..XYZToString(X-AdjacentTrack[i].X,Y-AdjacentTrack[i].Y,Z-AdjacentTrack[i].Z) .."[C]=" .. #AdjacentTracksConnections, sPlayer )

			end
		end

		--CHeck if placed track should be a corner and apply this effect last
		if (#AdjacentTracksConnections <= 1 and CornerMatch == nil) then
			--keep tabs on this adjacent track to see if I can form a corner piece from it
			CornerMatch = XYZToString(X-AdjacentTrack[i].X,Y-AdjacentTrack[i].Y,Z-AdjacentTrack[i].Z)
		end
		if (CornerMatch) then
			local RelXYZCornerMatch = XYZToString(X-AdjacentTrack[i].X,Y-AdjacentTrack[i].Y,Z-AdjacentTrack[i].Z)
			if (DefineCornerTrack[CornerMatch] and DefineCornerTrack[CornerMatch][RelXYZCornerMatch]) then
				World:SetBlockMeta(X,Y,Z,DefineCornerTrack[CornerMatch][RelXYZCornerMatch])
			end
		end
	end
end

UpdateMinecartTracks = false
PlacedTrack = {}



function MinecartTracksPlugin:OnBlockPlace(PacketData,Player)
	sPlayer = Player
	if( PacketData.m_ItemType == E_BLOCK_MINECART_TRACKS ) then
		local X = PacketData.m_PosX
		local Y = PacketData.m_PosY
		local Z = PacketData.m_PosZ
		local World = cRoot:Get():GetWorld()
		if (IsTrack(World:GetBlock(X,Y,Z))) then
			Player:GetInventory():AddItem(cItem(66,1))
		end
		X,Y,Z = AddDirection( X, Y, Z, PacketData.m_Direction)
		PlacedTrack = { ["X"] = X, ["Y"] = Y, ["Z"] = Z}
		UpdateMinecartTracks = true
	end
	return false
end

function MinecartTracksPlugin:Tick( DeltaTime )
	if ( UpdateMinecartTracks == true ) then
		local World = cRoot:Get():GetWorld()
		UpdateMinecartTracks = false
		if (IsTrack(World:GetBlock(PlacedTrack.X,PlacedTrack.Y-1,PlacedTrack.Z))) then
			World:SetBlock(PlacedTrack.X,PlacedTrack.Y,PlacedTrack.Z,0,0)
		else
			EvaluateConnections(PlacedTrack.X,PlacedTrack.Y,PlacedTrack.Z)
		end
	end
end

Plugin = MinecartTracksPlugin:new()
cRoot:Get():GetPluginManager():AddPlugin( Plugin )