package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"github.com/veandco/go-sdl2/sdl"
	"log"
	"net"
	"os"
	"sync"
	"time"
)

const GameVersion = "0.0.1"

type ServerConfig struct {
	MapWidth    uint32 `json:"map_width"`
	MapHeight   uint32 `json:"map_height"`
	BlastRadius uint8  `json:"blast_radius"`

	MaxEnergy     uint32 `json:"max_energy"`
	MaxAmmunition uint32 `json:"max_ammunition"`
	MaxShields    uint32 `json:"max_shields"`

	NormalShotCost        uint32 `json:"normal_shot_cost"`
	SuperShotCost         uint32 `json:"super_shot_cost"`
	ReloadCost            uint32 `json:"reload_cost"`
	MovementCost          uint32 `json:"movement_cost"`
	DiggingCost           uint32 `json:"digging_cost"`
	ShootDiggingCostBonus uint32 `json:"shoot_digging_cost_bonus"`

	ShootCooldown            uint32 `json:"shoot_cooldown"`
	RechargeCooldownOwn      uint32 `json:"recharge_cooldown_own"`
	DiggingCooldown          uint32 `json:"digging_cooldown"`
	RechargeCooldownOpponent uint32 `json:"recharge_cooldown_opponent"`
	RepairCooldown           uint32 `json:"repair_cooldown"`
	MovementCooldown         uint32 `json:"movement_cooldown"`
	MovementCooldownNoEnergy uint32 `json:"movement_cooldown_no_energy"`
	DiggingCooldownNoEnergy  uint32 `json:"digging_cooldown_no_energy"`
	ReloadCooldown           uint32 `json:"reload_cooldown"`
	ReloadWait               uint32 `json:"reload_wait"`
}

type Config struct {
	Debug                          bool         `json:"debug"`
	MapWindow                      bool         `json:"map_window"`
	MapUpdateInterval              uint16       `json:"map_update_interval"`
	RenderGameObjects              bool         `json:"render_game_objects"`
	ProfilerOn                     bool         `json:"profiler_on"`
	ProfilerInterval               uint64       `json:"profiler_interval"`
	Server                         bool         `json:"server"`
	CameraW                        int32        `json:"camera_w"`
	CameraH                        int32        `json:"camera_h"`
	Client                         bool         `json:"client"`
	Address                        string       `json:"address"`
	JoyStickDeadZone               int16        `json:"joystick_dead_zone"`
	DoAllKeymapsPlayers            bool         `json:"do_all_keymaps_players"`
	DoJoyStickPlayers              bool         `json:"do_joystick_players"`
	DoKeymapPlayer                 bool         `json:"do_keymap_player"`
	RecentlyDugBlocksClearInterval uint16       `json:"recently_dug_blocks_clear_interval"`
	KeyBindOffset                  uint16       `json:"key_bind_offset"`
	ServerConfig                   ServerConfig `json:"server_config"`
}

func loadOrCreateConfig(filename string) (*Config, error) {
	config := &Config{
		Debug:                          false,
		MapWindow:                      false,
		MapUpdateInterval:              999,
		RenderGameObjects:              true,
		ProfilerOn:                     false,
		ProfilerInterval:               100,
		Server:                         false,
		CameraW:                        76,
		CameraH:                        76,
		Client:                         true,
		Address:                        "192.168.1.8:5074",
		JoyStickDeadZone:               8000,
		DoAllKeymapsPlayers:            false,
		DoJoyStickPlayers:              true,
		DoKeymapPlayer:                 true,
		RecentlyDugBlocksClearInterval: 20,
		KeyBindOffset:                  0,
		ServerConfig: ServerConfig{
			MapWidth:    1000,
			MapHeight:   1000,
			BlastRadius: 5,

			MaxEnergy:     3520,
			MaxAmmunition: 6,
			MaxShields:    100,

			NormalShotCost:        7,
			SuperShotCost:         80,
			ReloadCost:            4,
			MovementCost:          1,
			DiggingCost:           3,
			ShootDiggingCostBonus: 1,

			ShootCooldown:            8,
			RechargeCooldownOwn:      0,
			DiggingCooldown:          4,
			RechargeCooldownOpponent: 6,
			RepairCooldown:           4,
			MovementCooldown:         2,
			MovementCooldownNoEnergy: 4,
			DiggingCooldownNoEnergy:  8,
			ReloadCooldown:           16,
			ReloadWait:               16,
		},
	}

	// Check if the file exists
	if _, err := os.Stat(filename); os.IsNotExist(err) {
		// File does not exist, create it with the default config
		data, err := json.MarshalIndent(config, "", "  ")
		if err != nil {
			return nil, fmt.Errorf("failed to marshal config: %v", err)
		}

		err = os.WriteFile(filename, data, 0644)
		if err != nil {
			return nil, fmt.Errorf("failed to write config file: %v", err)
		}
		fmt.Println("Config file created with default values.")
	} else {
		// File exists, load the config
		data, err := os.ReadFile(filename)
		if err != nil {
			return nil, fmt.Errorf("failed to read config file: %v", err)
		}

		err = json.Unmarshal(data, config)
		if err != nil {
			return nil, fmt.Errorf("failed to unmarshal config: %v", err)
		}
		fmt.Println("Config file loaded.")
	}

	return config, nil
}

var config *Config

var gameMap = &GameMap{}

var serverConfig ServerConfig

var mapWindow *sdl.Window
var mapSurface *sdl.Surface
var mapRendererRect *sdl.Rect

var netPlayerMapper = map[*net.TCPConn]*Player{}

var clientInitialized = false

var worldLock sync.Mutex

var totalRenderTime, totalGameLogicCatchUp, totalNormalGameLogic, totalTicking, totalScalingTime, totalRemotePlayerUpdate, tickCount, totalFrameTime, frameCount uint64

func main() {
	configX, err := loadOrCreateConfig("config.json")
	if err != nil {
		log.Fatal(err)
	}
	serverConfig = configX.ServerConfig
	config = configX

	if !(config.Server && !config.DoKeymapPlayer && !config.DoJoyStickPlayers && !config.DoAllKeymapsPlayers && !config.MapWindow) {
		initializeSDL()
		defer sdl.Quit()
	}
	mapRendererRect = &sdl.Rect{X: 0, Y: 0, W: int32(serverConfig.MapWidth), H: int32(serverConfig.MapHeight)}
	players := make(map[uint32]*Player)
	initPlayerColors()
	bullets := make(map[uint32]*Bullet)
	bulletParticles := make(map[uint32]*BulletParticle)
	bases := make(map[uint32]*Base)

	if config.Client && config.Server {
		panic("You can' t run client and server in the same instance")
	}

	if !config.Client {
		gameMap.createGameMap(true)
		createPlayers(getNeededPlayers(), playerColors, keyMaps, joyMaps, gameMap, players, bases)
		bases = createBases(players, gameMap)
	} else {
		// Create a connection to the server
		addr, err := net.ResolveTCPAddr("tcp", config.Address)

		if err != nil {
			log.Fatal("Error resolving address " + config.Address + ": " + err.Error())
		}

		conn, err := net.DialTCP("tcp", nil, addr)
		if err != nil {
			log.Fatalf("Failed to connect to server: %v", err)
		}
		defer func(conn *net.TCPConn) {
			_ = conn.Close()
		}(conn)

		go handleConnectionClient(conn, players, bases, bullets, bulletParticles)
		for !clientInitialized {
			time.Sleep(100 * time.Millisecond)
		}
	}

	defer closeThings(players)

	playersMutex.Lock()
	for playerIndex, player := range players {
		initPlayer(uint8(playerIndex), player)
	}
	playersMutex.Unlock()

	if config.Server {
		// Create a connection to the server
		addr, err := net.ResolveTCPAddr("tcp", config.Address)

		if err != nil {
			log.Fatal("Error resolving address " + config.Address + ": " + err.Error())
		}
		listen, err := net.ListenTCP("tcp", addr)
		if err != nil {
			log.Fatal(err)
		}
		// close listener
		defer func(listen *net.TCPListener) {
			_ = listen.Close()
		}(listen)
		go func() {
			for {
				conn, err := listen.AcceptTCP()
				if err != nil {
					var opErr *net.OpError
					if errors.As(err, &opErr) && opErr.Err.Error() == "use of closed network connection" {
						log.Println("Listener closed, stopping server.")
						return
					}
					log.Println("Error accepting connection:", err)
					continue
				}
				go handleRequest(conn, players, bullets, bases)
			}
		}()
	}

	if config.MapWindow {
		mapWindow, mapSurface = setupMapWindowAndSurface()
	}
	running := true

	// Delta time management
	var prevTime = sdl.GetTicks64()
	const maxDeltaTime uint64 = 1000 / 60 // max 60 FPS, ~16ms per frame

	for running {
		currentTime := sdl.GetTicks64()
		deltaTime := currentTime - prevTime
		prevTime = currentTime
		worldLock.Lock()

		totalGameLogicCatchUp += profileSection(func() {
			// Catch up in case of a large delta time
			for deltaTime > maxDeltaTime {
				deltaTime -= maxDeltaTime

				// Run multiple logic ticks if deltaTime is too large
				runGameLogic(players, gameMap, bases, bullets, bulletParticles)
			}
		})
		totalNormalGameLogic += profileSection(func() {
			// Run logic for the remaining delta time
			runGameLogic(players, gameMap, bases, bullets, bulletParticles)
		})

		playersMutex.RLock()
		for playerIndex, player := range players {
			if player.local {
				running = doPlayerFrame(uint8(playerIndex), player, players, gameMap, bases, bullets, bulletParticles)
				if !running {
					break
				}
			}
		}
		playersMutex.RUnlock()

		// Render logic
		if config.MapWindow && frameCount%uint64(config.MapUpdateInterval) == 0 {
			// Profile rendering (aggregate all renderings)
			totalRenderTime += profileSection(func() {
				running = running && handleEvents(mapWindow, mapSurface)
				gameMap.render(mapRendererRect, mapSurface)
				bulletMutex.RLock()
				for _, bullet := range bullets {
					(*bullet).render(mapRendererRect, mapSurface, bullets)
				}
				bulletMutex.RUnlock()
				baseMutex.RLock()
				for _, base := range bases {
					(*base).render(mapRendererRect, mapSurface, bases)
				}
				baseMutex.RUnlock()
				playersMutex.RLock()
				for _, playerLoop := range players {
					(*playerLoop).render(mapRendererRect, mapSurface, players)
				}
				playersMutex.RUnlock()
				bulletParticleMutex.RLock()
				for _, bulletParticle := range bulletParticles {
					bulletParticle.render(mapRendererRect, mapSurface, bulletParticles)
				}
				bulletParticleMutex.RUnlock()
			})
			totalScalingTime += profileSection(func() {
				adjustWindow(mapWindow, mapSurface)
			})
		}

		frameEnd := sdl.GetTicks64()
		totalFrameTime += frameEnd - currentTime
		frameCount++

		// Log profiling information every 1000 frames
		if frameCount%config.ProfilerInterval == 0 && config.ProfilerOn {
			logMapProfilingInfo(totalRenderTime, totalScalingTime, totalFrameTime, totalGameLogicCatchUp, totalNormalGameLogic, totalTicking, totalRemotePlayerUpdate, frameCount, tickCount)
			resetMapProfilingCounters(&totalRenderTime, &totalScalingTime, &totalFrameTime, &totalGameLogicCatchUp, &totalNormalGameLogic, &totalTicking, &totalRemotePlayerUpdate, &frameCount, &tickCount)
		}
		worldLock.Unlock()
		enforceFrameRate(currentTime, 60)
	}
}

// Separate function to handle game logic
func runGameLogic(players map[uint32]*Player, gameMap *GameMap, bases map[uint32]*Base, bullets map[uint32]*Bullet, bulletParticles map[uint32]*BulletParticle) {
	// Tick world

	if config.Server {
		//update remote player maps
		totalRemotePlayerUpdate += profileSection(func() {
			var wgX sync.WaitGroup
			playerUpdateMutex.Lock()
			playersMutex.RLock()
			for _, player := range players {
				if player.local || !player.initialized {
					continue
				}
				wgX.Add(6)
				go player.updateRemotePlayerBases(bases, players, &wgX)
				go player.updateRemotePlayerMap(&wgX)
				go player.updateRemotePlayerBullets(bullets, &wgX)
				go player.updateRemotePlayerBulletParticles(bulletParticles, &wgX)
				go player.updateRemotePlayerPlayers(players, &wgX)
				playerX := player
				go func() {
					success := playerX.sendPlayerUpdate(&wgX)
					if !success {
						if playerX.connection != nil {
							_ = (*playerX.connection).Close()
						}
						baseMutex.Lock()
						if bases[playerX.playerID] != nil {
							bases[playerX.playerID].delete(bases)
						}
						baseMutex.Unlock()
						playersMutex.TryLock()
						delete(players, playerX.playerID)
						playersMutex.Unlock()
					}
				}()
			}
			playersMutex.RUnlock()
			wgX.Wait()
			playerUpdateMutex.Unlock()
		})
	}
	totalTicking += profileSection(func() {
		playerUpdateMutex.Lock()
		bulletMutex.RLock()
		for _, bullet := range bullets {
			(*bullet).tick(gameMap, bulletParticles, bullets, players)
		}
		bulletMutex.RUnlock()
		playersMutex.RLock()
		for _, player := range players {
			if player.local {
				continue
			}
			(*player).tick(bullets)
		}
		playersMutex.RUnlock()
		baseMutex.RLock()
		for _, base := range bases {
			(*base).tick(players)
		}
		baseMutex.RUnlock()
		bulletParticleMutex.RLock()
		for _, bulletParticle := range bulletParticles {
			bulletParticle.tick(bulletParticles)
		}
		bulletParticleMutex.RUnlock()
		playerUpdateMutex.Unlock()
	})
	tickCount++
}

func initPlayer(playerIndex uint8, player *Player) {
	if !player.local {
		return
	}
	player.window, player.logicalSurface = setupWindowAndSurface(playerIndex)
	logicalColor := sdl.MapRGBA(player.logicalSurface.Format, 101, 101, 0, 255)
	_ = player.logicalSurface.FillRect(nil, logicalColor)

	player.playSurface, player.playSurfaceRect, player.playSurfaceTargetRect = setupPlaySurface()
	playColor := sdl.MapRGBA(player.playSurface.Format, 101, 0, 101, 255)
	_ = player.playSurface.FillRect(nil, playColor)

	player.HUDSurface, player.HUDSurfaceRect, player.HUDSurfaceTargetRect = setupHUDSurface()
	initHud(player.HUDSurface)
	player.camera = &sdl.Rect{X: 0, Y: 0, W: config.CameraW, H: config.CameraH}
}

func doPlayerFrame(playerIndex uint8, player *Player, players map[uint32]*Player, gameMap *GameMap, bases map[uint32]*Base, bullets map[uint32]*Bullet, bulletParticles map[uint32]*BulletParticle) bool {
	running := true
	var (
		shouldContinue bool
	)
	frameStart := sdl.GetTicks64()

	// Profile handleEvents
	player.totalHandleEventsTime += profileSection(func() {
		running = handleEvents(player.window, player.logicalSurface)
		keyboard := sdl.GetKeyboardState()
		shouldContinue = handleInput(keyboard, bullets, player, gameMap, players)
		running = running && shouldContinue
	})

	// Profile rendering (aggregate all renderings)
	player.totalRenderTime += profileSection(func() {
		player.track(player.camera)
		gameMap.render(player.camera, player.playSurface)

		bulletMutex.RLock()
		for _, bullet := range bullets {
			(*bullet).render(player.camera, player.playSurface, bullets)
		}
		bulletMutex.RUnlock()
		baseMutex.RLock()
		for _, base := range bases {
			(*base).render(player.camera, player.playSurface, bases)
		}
		baseMutex.RUnlock()
		playersMutex.RLock()
		for _, playerLoop := range players {
			(*playerLoop).render(player.camera, player.playSurface, players)
		}
		playersMutex.RUnlock()
		bulletParticleMutex.RLock()
		for _, bulletParticle := range bulletParticles {
			bulletParticle.render(player.camera, player.playSurface, bulletParticles)
		}
		bulletParticleMutex.RUnlock()

		player.tick(bullets)
		player.gameObject.prevBaseRect = player.gameObject.baseRect
		renderHud(player, player.HUDSurface)
		_ = player.playSurface.BlitScaled(player.playSurfaceRect, player.logicalSurface, player.playSurfaceTargetRect)
		_ = player.HUDSurface.BlitScaled(player.HUDSurfaceRect, player.logicalSurface, player.HUDSurfaceTargetRect)
	})

	// Profile window adjustments
	player.totalScalingTime += profileSection(func() {
		adjustWindow(player.window, player.logicalSurface)
	})

	frameEnd := sdl.GetTicks64()
	player.totalFrameTime += frameEnd - frameStart
	player.frameCount++

	// Log profiling information every 1000 frames
	if player.frameCount%config.ProfilerInterval == 0 && config.ProfilerOn && playerIndex == 0 {
		logProfilingInfo(player.totalHandleEventsTime, player.totalRenderTime, player.totalScalingTime, player.totalFrameTime, player.frameCount)
		resetProfilingCounters(&player.totalHandleEventsTime, &player.totalRenderTime, &player.totalScalingTime, &player.totalFrameTime, &player.frameCount)
	}
	return running
}