-- separate_spawns.lua
-- Nov 2016
--
-- Code that handles everything regarding giving each player a separate spawn
-- Includes the GUI stuff


--------------------------------------------------------------------------------
-- EVENT RELATED FUNCTIONS
--------------------------------------------------------------------------------

-- When a new player is created, present the spawn options
-- Assign them to the main force so they can communicate with the team
-- without shouting.
function SeparateSpawnsPlayerCreated(event)
    local player = game.players[event.player_index]
    player.force = MAIN_FORCE
    DisplayWelcomeTextGui(player)
end


-- Check if the player has a different spawn point than the default one
-- Make sure to give the default starting items
function SeparateSpawnsPlayerRespawned(event)
    local player = game.players[event.player_index]
    SendPlayerToSpawn(player)
end


-- This is the main function that creates the spawn area
-- Provides resources, land and a safe zone
function SeparateSpawnsGenerateChunk(event)
    local surface = event.surface
    local chunkArea = event.area
    
    -- This handles chunk generation near player spawns
    -- If it is near a player spawn, it does a few things like make the area
    -- safe and provide a guaranteed area of land and water tiles.
    CreateSpawnAreas(surface, chunkArea, global.uniqueSpawns)
end


-- Call this if a player leaves the game
-- Seems to be susceptiable to causing desyncs...
function FindUnusedSpawns(event)
    local player = game.players[event.player_index]
    if (player.online_time < MIN_ONLINE_TIME) then

        DropGravestoneChests(player)

        -- Clear out global variables for that player???
        if (global.playerSpawns[player.name] ~= nil) then
            global.playerSpawns[player.name] = nil
        end

        -- If a uniqueSpawn was created for the player, mark it as unused.
        if (global.uniqueSpawns[player.name] ~= nil) then
            table.insert(global.unusedSpawns, global.uniqueSpawns[player.name])
            
            -- TODO: Test player joining and leaving quickly to ensure
            -- spawn points are not messed up...
            -- global.uniqueSpawns[player.name] = nil
            SendBroadcastMsg(player.name .. " base was freed up because they left within 5 minutes of joining.")
        end
        
        -- Remove from shared spawns
        if (global.sharedSpawns[player.name] ~= nil) then
            global.sharedSpawns[player.name] = nil
        end

        -- remove that player's cooldown setting
        if (global.playerCooldowns[player.name] ~= nil) then
            global.playerCooldowns[player.name] = nil
        end

        -- Remove from shared spawn player slots (need to search all)
        for _,sharedSpawn in pairs(global.sharedSpawns) do
            for key,playerName in pairs(sharedSpawn.players) do
                if (player.name == playerName) then
                    sharedSpawn.players[key] = nil;
                end
            end
        end

        -- Remove a force if this player created it and they are the only one on it
        if (#player.force.players <= 1) then
            game.merge_forces(player.force, MAIN_FORCE)
        end

        -- Remove the character completely
        game.remove_offline_players({player})
    end
end


--------------------------------------------------------------------------------
-- NON-EVENT RELATED FUNCTIONS
-- These should be local functions where possible!
--------------------------------------------------------------------------------

-- Add a spawn to the shared spawn global
-- Used for tracking which players are assigned to it, where it is and if
-- it is open for new players to join
function CreateNewSharedSpawn(player)
    global.sharedSpawns[player.name] = {openAccess=true,
                                    position=global.playerSpawns[player.name],
                                    players={}}
end

-- Returns the number of players currently online at the shared spawn
function GetOnlinePlayersAtSharedSpawn(ownerName)
    if (global.sharedSpawns[ownerName] ~= nil) then

        -- Does not count base owner
        local count = 0

        -- For each player in the shared spawn, check if online and add to count.
        for _,player in pairs(game.connected_players) do
            if (ownerName == player.name) then
                count = count + 1
            end

            for _,playerName in pairs(global.sharedSpawns[ownerName].players) do
            
                if (playerName == player.name) then
                    count = count + 1
                end
            end
        end

        return count
    else
        return 0
    end
end

-- Get the number of currently available shared spawns
-- This means the base owner has enabled access AND the number of online players
-- is below the threshold.
function GetNumberOfAvailableSharedSpawns()
    local count = 0

    for ownerName,sharedSpawn in pairs(global.sharedSpawns) do
        if (sharedSpawn.openAccess) then
            if (GetOnlinePlayersAtSharedSpawn(ownerName) < MAX_ONLINE_PLAYERS_AT_SHARED_SPAWN) then
                count = count+1
            end
        end
    end

    return count
end


-- Initializes the globals used to track the special spawn and player
-- status information
function InitSpawnGlobalsAndForces()
    -- Containes an array of all player spawns
    -- A secondary array tracks whether the character will respawn there.
    if (global.playerSpawns == nil) then
        global.playerSpawns = {}
    end
    if (global.uniqueSpawns == nil) then
        global.uniqueSpawns = {}
    end
    if (global.sharedSpawns == nil) then
        global.sharedSpawns = {}
    end
    if (global.unusedSpawns == nil) then
        global.unusedSpawns = {}
    end
    if (global.playerCooldowns == nil) then
        global.playerCooldowns = {}
    end

    game.create_force(MAIN_FORCE)
    game.forces[MAIN_FORCE].set_spawn_position(game.forces["player"].get_spawn_position(GAME_SURFACE_NAME), GAME_SURFACE_NAME)
    SetCeaseFireBetweenAllForces()
    SetFriendlyBetweenAllForces()
    AntiGriefing(game.forces[MAIN_FORCE])
end


function DoesPlayerHaveCustomSpawn(player)
    for name,spawnPos in pairs(global.playerSpawns) do
        if (player.name == name) then
            return true
        end
    end
    return false
end

function ChangePlayerSpawn(player, pos)
    global.playerSpawns[player.name] = pos
    global.playerCooldowns[player.name] = {setRespawn=game.tick}
end

function SendPlayerToNewSpawnAndCreateIt(player, spawn)
    -- Send the player to that position
    player.teleport(spawn, GAME_SURFACE_NAME)
    GivePlayerStarterItems(player)
    ChartArea(player.force, player.position, 4, player.surface)

    -- If we get a valid spawn point, setup the area
    if ((spawn.x ~= 0) and (spawn.y ~= 0)) then
        global.uniqueSpawns[player.name] = spawn
        ClearNearbyEnemies(player, SAFE_AREA_TILE_DIST)
    else      
        DebugPrint("THIS SHOULD NOT EVER HAPPEN! Spawn failed!")
        SendBroadcastMsg("Failed to create spawn point for: " .. player.name)
    end
end

function SendPlayerToSpawn(player)
    if (DoesPlayerHaveCustomSpawn(player)) then
        player.teleport(global.playerSpawns[player.name], GAME_SURFACE_NAME)
    else
        player.teleport(game.forces[MAIN_FORCE].get_spawn_position(GAME_SURFACE_NAME), GAME_SURFACE_NAME)
    end
end

function SendPlayerToRandomSpawn(player)
    local numSpawns = TableLength(global.uniqueSpawns)
    local rndSpawn = math.random(0,numSpawns)
    local counter = 0

    if (rndSpawn == 0) then
        player.teleport(game.forces[MAIN_FORCE].get_spawn_position(GAME_SURFACE_NAME), GAME_SURFACE_NAME)
    else
        counter = counter + 1
        for name,spawnPos in pairs(global.uniqueSpawns) do
            if (counter == rndSpawn) then
                player.teleport(spawnPos)
                break
            end
            counter = counter + 1
        end 
    end
end

function CreatePlayerCustomForce(player)
    local newForce = nil
    
    -- Check if force already exists
    if (game.forces[player.name] ~= nil) then
        DebugPrint("Force already exists!")
        player.force = game.forces[player.name]
        return game.forces[player.name]

    -- Create a new force using the player's name
    elseif (TableLength(game.forces) < MAX_FORCES) then
        newForce = game.create_force(player.name)
        player.force = newForce
        SetCeaseFireBetweenAllForces()
        SetFriendlyBetweenAllForces() 
        SendBroadcastMsg(player.name.." has started their own team!")     
    else
        player.force = MAIN_FORCE
        player.print("Sorry, no new teams can be created. You were assigned to the default team instead.")
    end

    return newForce
end

-- For each force, if it's a valid force, chart the chunk that all active players
-- are in.
-- I have no idea how compute intensive this function is. If it starts to lag the game
-- we'll have to figure out how to change it.
function ShareVisionBetweenPlayers()
    for _,force in pairs(game.forces) do
        if (force~=nil) then
            if ((force.name~=enemy) and
                (force.name ~=neutral) and
                (force.name ~=player)) then

                for _,player in pairs(game.connected_players) do
                    force.chart(GAME_SURFACE_NAME,
                                {{player.position.x-CHUNK_SIZE,
                                 player.position.y-CHUNK_SIZE},
                                 {player.position.x+CHUNK_SIZE,
                                 player.position.y+CHUNK_SIZE}})
                end

            end
        end
    end
end