--[[
Functions:
    SpawnMaze(maze (table), x (number), y (number), z (number) [, save (boolean)])
        Spawns a maze using 'maze' as a blueprint. 'x', 'y', 'z' determines the upper-left
        corner of the maze. 'save' determines if the maze is saved to the database (defaults
        to false).
        returns: nothing.
    SpawnMazeLoad(file (string), x (number), y (number), z (number) [, save (boolean)])
        Loads a maze from 'file'.txt and passes it to SpawnMaze().
        returns: nothing.
    GenerateMaze(width, height)
        Generates a maze with dimensions 'width'*2, 'height'*2. It also includes a
        start point (randomly selected at start of generation) and an end point
        (the point farthest from the start point at end of generation).
        Does not generate despawning walls.
        returns: a table representing the generated maze.

Please use SpawnMazeLoad() to actually spawn the maze! It gives much more power over
the final output, and allows placement of despawning walls!
Also, the 'save' argument should only be used when the maze is finalized, as it saves
the whole thing to the database.

Please follow these guidelines when editing a maze file:
    # = wall
    S = start point
    E = end point (defaults as the farthest point from start)
    H = despawning wall
    + = corridor
]]

local sizeW = 6 --Width of maze box
local sizeH = 5.5125 --Height of maze box
local Box1 = 50000 --Normal maze box (gameobject)
local Box2 = 50001 --Despawning wall (gameobject)
local StartDummy = 60010 --Start dummy (unit)
local EndDummy = 60016 --End dummy (unit)
local firstMaze = true
local Duration = 60 * 60 * 1000 --1 hour

mazeInfo = {
    generating = false,
    players = {},
    completed = {},
    currentMaze = {},
    Start,
    End,
    mazeStart = {0, 0, 0}
}

function SpawnMaze(maze, x, y, z)
    assert (type(maze) == "table", "Bad argument #1 to SpawnMaze (table expected, got "..type(maze)..")")
    for k, v in pairs (maze) do
        assert (type(v) == "string")
    end
    assert (type(x) == "number", "Bad argument #2 to SpawnMaze (number expected, got "..type(x)..")")
    assert (type(y) == "number", "Bad argument #3 to SpawnMaze (number expected, got "..type(y)..")")
    assert (type(z) == "number", "Bad argument #4 to SpawnMaze (number expected, got "..type(z)..")")
    for k, v in pairs (maze) do
        for i = 1, string.len(v) do
            local s = string.sub(v, i, i)
            local nX = x + (i * sizeW)
            local nY = y + (k * sizeW)
            if (s == "#") then --Wall
                local nZ = z
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
            elseif (s == "+") then --Corridor
                local nZ = z + sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z - sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
            elseif (s == "S") then --Start point dummy
                local nZ = z + sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z - sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z + 0.1
                PerformIngameSpawn(1, StartDummy, 13, nX, nY, nZ, 0, 35, Duration)
                mazeInfo.mazeStart[1] = nX
                mazeInfo.mazeStart[2] = nY
                mazeInfo.mazeStart[3] = nZ + 0.9
            elseif (s == "E") then --End point dummy
                local nZ = z + sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z - sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z + 0.1
                PerformIngameSpawn(1, EndDummy, 13, nX, nY, nZ, 0, 35, Duration)
            elseif (s == "H") then --Despawning wall
                local nZ = z
                PerformIngameSpawn(2, Box2, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z + sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z - sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
            else
                print ("Unhandled character \'"..s.."\' in maze spawning code. Replacing with corridor.")
                local nZ = z + sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
                nZ = z - sizeH
                PerformIngameSpawn(2, Box1, 13, nX, nY, nZ, 0, 400, Duration)
            end
        end
    end
end
function SpawnMazeLoad(file, x, y, z)
    local f = assert(io.open("scripts/dropbox/kronos/"..file..".txt"), "Bad argument #1 to SpawnMazeLoad (no .txt file with name "..file..")")
    assert (type(x) == "number", "Bad argument #2 to SpawnMazeLoad (number expected, got "..type(x)..")")
    assert (type(y) == "number", "Bad argument #3 to SpawnMazeLoad (number expected, got "..type(y)..")")
    assert (type(z) == "number", "Bad argument #4 to SpawnMazeLoad (number expected, got "..type(z)..")")
    local maze = {}
    for l in f:lines() do
        table.insert(maze, l)
    end
    f:close()
    SpawnMaze(maze, x, y, z)
end

function GenerateMaze(arg1, arg2)
    --Remember, width and height is doubled to make the recursive backtracking work with
    --uneven numbers, so a 10x10 maze actually becomes 20x20.
    --arg1 = width
    --arg2 = height
    assert (type(arg1) == "number", "Bad argument #1 to GenerateMaze (number expected, got "..type(arg1)..")")
    assert (type(arg2) == "number", "Bad argument #2 to GenerateMaze (number expected, got "..type(arg2)..")")
    local maze = {}
    for x = 1, arg1 * 2 do
        maze[x] = {}
        for y = 1, arg2 * 2 do
            maze[x][y] = {"#", 0, 0}
        end
    end
    local hash = (os.time() / os.clock()) + math.random(1, 2^16) - math.random(2^10, 2^16)
    math.randomseed(hash)
    local x = math.random(1, arg1) * 2
    local y = math.random(1, arg2) * 2
    maze[x][y][1] = "S"
    local startX = x
    local startY = y
    local fromStart = 0
    local longestFromStart = 0
    local fromStartX = 0
    local fromStartY = 0
    while (true) do
        local found = false
        local oldX = x
        local oldY = y
        local m = {}
        if (x < ((arg1 * 2) - 2) and maze[x+2][y][1] == "#") then
            table.insert(m, {x+2, y, 1})
        end
        if (x > 2 and maze[x-2][y][1] == "#") then
            table.insert(m, {x-2, y, 2})
        end
        if (y < ((arg2 * 2) - 2) and maze[x][y+2][1] == "#") then
            table.insert(m, {x, y+2, 3})
        end
        if (y > 2 and maze[x][y-2][1] == "#") then
            table.insert(m, {x, y-2, 4})
        end
        if ((#m) > 0) then
            fromStart = fromStart + 1
            local r = math.random(1, (#m))
            x = m[r][1]
            y = m[r][2]
            maze[x][y][1] = "+"
            maze[x][y][2] = oldX
            maze[x][y][3] = oldY
            if (m[r][3] == 1) then
                maze[x-1][y][1] = "+"
            elseif (m[r][3] == 2) then
                maze[x+1][y][1] = "+"
            elseif (m[r][3] == 3) then
                maze[x][y-1][1] = "+"
            else
                maze[x][y+1][1] = "+"
            end
        else
            if (fromStart > longestFromStart) then
                longestFromStart = fromStart
                fromStartX = x
                fromStartY = y
            end
            fromStart = fromStart - 1
            local tmp1 = x
            x = maze[x][y][2]
            y = maze[tmp1][y][3]
        end
        if (x == startX and y == startY) then
            maze[fromStartX][fromStartY][1] = "E"
            break
        end
    end
    local maze2 = {}
    for k1 = 1, ((arg1 * 2) - 1) do
        if (not maze2[k1]) then
            maze2[k1] = {}
        end
        for k2 = 1, ((arg2 * 2) - 1) do
            maze2[k1][k2] = maze[k1][k2][1]
        end
    end
    local Max = 0
    for k1, v1 in pairs (maze2) do
        for k2, v2 in pairs (v1) do
            local r = math.random(1, ((arg1 * arg2) / 5))
            if (Max < 10 and maze2[k1][k2] == "#" and r == 1) then
                local m = {}
                if (maze2[k1+2] and maze2[k1+2][k2] and maze2[k1+2][k2] == "+") then
                    table.insert(m, {k1+1, k2})
                end
                if (maze2[k1-2] and maze2[k1-2][k2] and maze2[k1-2][k2] == "+") then
                    table.insert(m, {k1-1, k2})
                end
                if (maze2[k1] and maze2[k1][k2+2] and maze2[k1][k2+2] == "+") then
                    table.insert(m, {k1, k2+1})
                end
                if (maze2[k1] and maze2[k1][k2-2] and maze2[k1][k2-2] == "+") then
                    table.insert(m, {k1, k2-1})
                end
                if ((#m) > 0) then
                    Max = Max + 1
                    maze2[k1][k2] = "+"
                end
            end
        end
    end
    local maze3 = {}
    for k1, v1 in pairs (maze2) do
        maze3[k1] = table.concat(v1)
    end
    return maze3
end

function GenerateNewMaze()
    mazeInfo.generating = true
    if (firstMaze) then
        firstMaze = false
    else
        for k, v in pairs (mazeInfo.players) do
            if (v) then
                v:Teleport(0, -7477.58, -1254.11, 477.4)
            end
            table.remove(k)
        end
    end
    CreateLuaEvent(DelayGeneration, 2000, 1)
end
function DelayGeneration()
    local maze = GenerateMaze(20, 20) --40x40
    SpawnMaze(maze, -100, -100, 250)
    mazeInfo.generating = false
end

function MazeCheckPlayers()
    if (not mazeInfo.generating) then
        for k, v in pairs (mazeInfo.players) do
            if (not v or (v:IsInWorld() and v:GetMapId() ~= 13)) then
                table.remove(mazeInfo.players, k)
            end
        end
    end
end

CreateLuaEvent(MazeCheckPlayers, 2000, 0)

function MazeDummyGossip(pUnit, event, player, id, intid)
    if (event == 1) then
        local tmp = true
        for k, v in pairs (mazeInfo.completed) do
            if (v:GetName() == player:GetName()) then
                tmp = false
            end
        end
        if (tmp) then
            table.insert(mazeInfo.completed, player)
            pUnit:SendChatMessageToPlayer(42, 0, "You have received 5 \124cffa335ee\124Hitem:29434:0:0:0:0:0:0:0:0\124h[Badge of Justice]\124h\124r for completing this course!", player)
            player:AddItem(29434, 5)
            player:CastSpell(47292)
        end
        pUnit:GossipCreateMenu(1, player, 0)
        pUnit:GossipMenuAddItem(2, "Return me to Blackrock Mountain.", 1, 0)
        pUnit:GossipMenuAddItem(0, "Nevermind.", 2, 0)
        pUnit:GossipSendMenu(player)
    elseif (event == 2) then
        if (intid == 1) then
            for k, v in pairs (mazeInfo.players) do
                if (v:GetName() == player:GetName()) then
                    table.remove(mazeInfo.players, k)
                end
            end
            player:GossipComplete()
            player:Teleport(0, -7555, -1200, 477)
        elseif (intid == 2) then
            player:GossipComplete()
        end
    end
end

RegisterUnitGossipEvent(EndDummy, 1, MazeDummyGossip)
RegisterUnitGossipEvent(EndDummy, 2, MazeDummyGossip)

CreateLuaEvent(GenerateNewMaze, 10000, 1)
CreateLuaEvent(GenerateNewMaze, Duration + 1000, 0)