package main

import (
	"math"
	"bytes"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	"os"
	"strconv"
	"time"

	"battlecamp-go/board"
	"battlecamp-go/events"
	"battlecamp-go/flag"
	"battlecamp-go/game"
	"battlecamp-go/player"
	"battlecamp-go/stomp"
)

func main() {
	initLogging()
	log.Println("Game bot version 0.1")

	flag.ParseFlags()
	pu := make(chan *events.PlayerUpdate)
	go subscribeToUpdate(pu)
	subscribeToGame(pu)
}

func subscribeToGame(pu chan *events.PlayerUpdate) {
	sub := stomp.Subscribe("game")

	for {
		announcement := <-sub
		gs := new(events.GameStart)
		json.Unmarshal(announcement.Body, &gs)
		log.Printf("announcement type: %v ", strconv.FormatInt(gs.GameId, 10))
		gameEndChan := make(chan bool)
		if "GAME_START" == gs.Type {
			go joinGame(gs.GameId, gameEndChan, pu)
		} else {
			gameEndChan <- true
		}
	}
}

func subscribeToUpdate(pu chan *events.PlayerUpdate) {
	sub := stomp.Subscribe("update")

	for {
		announcement := <-sub
		if "vnd.battlecamp.player" == announcement.ContentType {
			p := new(player.Player)
			json.Unmarshal(announcement.Body, &p)
			playerJoin(p)
		} else {
			pue := new(events.PlayerUpdate)
			json.Unmarshal(announcement.Body, &pue)
			pu <- pue
		}
	}
}

func joinGame(gameId int64, gameEndChan chan bool, pu chan *events.PlayerUpdate) {
	//join game
	p := &player.Player{
		Id:    "Zeus",
		Color: "#238b02",
		Type:  1,
	}

	players := make([]*player.Player, 5)

	//retrieve finish
	gameUrl := "http://localhost:8080/games/" + strconv.FormatInt(gameId, 10)
	fmt.Println("getGame:>", gameUrl)
	resp, _ := http.Get(gameUrl)
	g := new(game.Game)
	b, _ := ioutil.ReadAll(resp.Body)
	json.Unmarshal(b, &g)
	boardSummery := g.Board
	fmt.Printf("Finish x=%v y=%v\n", boardSummery.Finish.X, boardSummery.Finish.Y)

	//join the game
	url := "http://localhost:8080/games/" + strconv.FormatInt(gameId, 10) + "/join"

	jsonStr, _ := json.Marshal(p)
	req, _ := http.NewRequest("POST", url, bytes.NewBuffer(jsonStr))
	req.Header.Set("Content-Type", "application/json")

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		panic(err)
	}
	v, _ := ioutil.ReadAll(resp.Body)
	json.Unmarshal(v, p) //Set my location in the player
	fmt.Printf("My start position x %v y %v\n", p.Pos.X, p.Pos.Y)
	resp.Body.Close()

	//determine to avoind north or south
	north := true
	if boardSummery.Finish.Y > p.Pos.Y {
		north = false
	}

	for {
		select {
		case <-gameEndChan:
			return
		case playerUpdate := <-pu:
			if playerUpdate.GameId == gameId {
				players = playerUpdate.Players
				for _, pup := range players {
					if pup.Id == p.Id {
						p.Pos.X = pup.Pos.X
						p.Pos.Y = pup.Pos.Y
						fmt.Printf("Set position to x=%v y=%v\n", pup.Pos.X, pup.Pos.Y)
					}
				}
			}
		default:
			move(gameId, p, players, boardSummery, north)
			time.Sleep(2 * time.Second)
		}
	}
}

type viewport struct {
	x, y, width, height int
	Board               *board.Board
}

func getViewPort(x, y, width, height int, gameId int64, bs *board.Board) *viewport {
	x = max(x, 0)
	x = min(x, bs.Width)
	y = max(y, 0)
	y = min(y, bs.Height)
	if x+width > bs.Width {
		width = bs.Width - x
	}
	if y+height > bs.Height {
		height = bs.Height - x
	}
	url := "http://localhost:8080/games/board/" + strconv.FormatInt(gameId, 10) + "?x=" + strconv.Itoa(x) + "&y=" + strconv.Itoa(y) + "&rows=" + strconv.Itoa(width) + "&cols=" + strconv.Itoa(height)
	fmt.Println("getViewPort:>", url)
	resp, _ := http.Get(url)
	board := board.ReadJSON(x, y, resp.Body)
	return &viewport{
		x:      x,
		y:      y,
		width:  width,
		height: height,
		Board:  board,
	}
}

func (v viewport) Get(x, y int) board.TileType {
	fmt.Printf("retrieving from viewport x %v y %v position in viewport x %v y %v", x, y, x-v.x, y-v.y)
	return v.Board.Get(x-v.x, y-v.y)
}

const viewPortWidth = 32
const viewPortHeight = 32

func max(a, b int) int {
	if a >= b {
		return a
	}
	return b
}

func min(a, b int) int {
	if a <= b {
		return a
	}
	return b
}

func move(gameId int64, p *player.Player, players []*player.Player, bs *board.Board, north bool) {
	//determine move

	viewPortX := p.Pos.X - 1
	viewPortY := p.Pos.Y - 1
	if north {
		viewPortX = viewPortX - viewPortHeight
	}

	viewPort := getViewPort(viewPortX, viewPortY, viewPortWidth, viewPortHeight, gameId, bs)

	direction := "W"

	fmt.Printf("p.Pos.X+1 %v p.Pos.Y %v\n", p.Pos.X+1, p.Pos.Y)

	if viewPort.Get(p.Pos.X+1, p.Pos.Y) != board.Rock {
		direction = "E"
	}
	var igloY int
	if bs.Finish.Y > viewPort.y {
		//iglo ten noorden van ons
		igloY = 0
		/*for  viewPort.Get(viewPort.x+viewPortWidth, igloY) == board.Rock && igloY <= viewPort.y+viewPortHeight {
			igloY++
		}*/
	} else if(bs.Finish.Y < viewPort.y+viewPortHeight) {
		//iglo ten zuiden van ons
		igloY = viewPort.Board.Height-1
		/*for  viewPort.Get(viewPort.x+viewPortWidth, igloY) == board.Rock  && igloY >= viewPort.y+viewPortHeight {
			igloY--
		}*/
	} else {
		igloY = bs.Finish.Y
	}
	igloX := viewPort.Board.Width
	calcDist(igloX, igloY, viewPort)
	
	
	smallestDist := math.MaxInt32
	
	
	
	
	//send move
	url := "http://localhost:8080/games/" + strconv.FormatInt(gameId, 10) + "/move/" + p.Id + "/" + direction
	fmt.Println("move:>", url, smallestDist)

	http.Post(url, "text/plain", nil)

	//update x,y
	switch direction {
	case "N":
		p.Pos.Y++
	case "E":
		p.Pos.X++
	case "S":
		p.Pos.Y--
	case "W":
		p.Pos.Y++
	}
	fmt.Printf("new pos x=%v y=%v\n", p.Pos.X, p.Pos.Y)
}



func toXy(index, boardWidth int) (x, y int) {
	x = index % boardWidth
	y = (index-x)/boardWidth
	return x,y 
}

func toIndex(x,y , boardWidth int) (index int) {
	return y*boardWidth+x
}

func calcDist(igloX, igloY int, viewPort *viewport) map[int]int {
	distance := make(map[int]int)
	
	s := stack{}
	index := toIndex(igloX, igloY, viewPort.Board.Width)
	s.Put(index)
	distance[index] = -1
	for !s.Empty() {
		i := s.Pop()
		x, y := toXy(i, viewPort.Board.Width)
		if(x+1 < viewPort.width) {
			newI := toIndex(x+1, y, viewPort.Board.Width)
			
			if(distance[newI] == 0 && viewPort.Board.Get(x+1, y) != board.Rock) {
				distance[newI] = distance[toIndex(x, y, viewPort.Board.Width)] + 1
				s.Put(newI)
			}
		}
		if(x-1 > 0) {
			newI := toIndex(x-1, y, viewPort.Board.Width)
			if(distance[newI] == 0 && viewPort.Board.Get(x+1, y) != board.Rock) {
				distance[newI] = distance[toIndex(x, y, viewPort.Board.Width)] + 1
				s.Put(newI)
			}
		}
		if(y+1 < viewPort.height) {
			newI := toIndex(x, y+1, viewPort.Board.Width)
			if(distance[newI] == 0 && viewPort.Board.Get(x+1, y) != board.Rock) {
				distance[newI] = distance[toIndex(x, y, viewPort.Board.Width)] + 1
				s.Put(newI)
			}
		}
		
		if(y-1 > 0) {
			newI := toIndex(x, y-1, viewPort.Board.Width)
			if(distance[newI] == 0 && viewPort.Board.Get(x+1, y) != board.Rock) {
				distance[newI] = distance[toIndex(x, y, viewPort.Board.Width)] + 1
				s.Put(newI)
			}
		}
	}
	return distance
}

type stack []int

func (s stack) Empty() bool { return len(s) == 0 }
func (s stack) Peek() int   { return s[len(s)-1] }
func (s *stack) Put(i int)  { (*s) = append((*s), i) }
func (s *stack) Pop() int {
  d := (*s)[len(*s)-1]
  (*s) = (*s)[:len(*s)-1]
  return d
}

func playerJoin(p *player.Player) {

}

func initLogging() {
	logFile, err := os.Create("server.log")

	if err == nil {
		log.SetOutput(logFile)
	} else {
		log.Println("ERROR: Cannot open log file, using console.")
		log.Printf("%v=n", err)
	}
}