package main

import (
	"github.com/aquilax/go-perlin"
	"github.com/veandco/go-sdl2/sdl"
	"image/color"
	"time"
)

type GameMap struct {
	tiles [][]uint8
	//tile 0 - air
	//tile 1 - rock
	//tile 2 - soil 1
	//tile 3 - soil 2
	//tile 4 - base
	//tile 5 - world edge (should not be present in the map object)
	width  int32
	height int32
}

func GetTileColorValue(value uint8) color.Color {
	switch value {
	case 0:
		return color.RGBA{}
	case 1:
		return color.RGBA{R: 154, G: 154, B: 154, A: 255}
	case 2:
		return color.RGBA{R: 195, G: 121, B: 48, A: 255}
	case 3:
		return color.RGBA{R: 186, G: 89, B: 4, A: 255}
	case 4:
		return color.RGBA{R: 255, G: 44, B: 255, A: 255}
	case 5:
		return color.RGBA{R: 86, G: 86, B: 86, A: 255}
	default:
		return color.RGBA{R: 255, G: 255, B: 255, A: 255}
	}
}

func (gameMap *GameMap) getTileColor(x int32, y int32) color.Color {
	if x < 0 || x >= gameMap.width || y < 0 || y >= gameMap.height {
		return GetTileColorValue(5)
	} else {
		tileValue := gameMap.tiles[x][y]
		return GetTileColorValue(tileValue)
	}
}

func (gameMap *GameMap) createGameMap(width int32, height int32) {
	gameMap.tiles = make([][]uint8, width)
	perlinNoiseRock := perlin.NewPerlin(2, 2, 4, time.Now().Unix())
	perlinNoiseSoil := perlin.NewPerlin(2, 8, 4, time.Now().Unix())
	for i := range gameMap.tiles {
		gameMap.tiles[i] = make([]uint8, height)
		for j := range gameMap.tiles[i] {
			perlinRock := perlinNoiseRock.Noise2D(float64(i)/float64(width)*3, float64(j)/float64(height)*3)
			if perlinRock > 0.2 {
				gameMap.tiles[i][j] = 1
			} else {
				perlinSoil := perlinNoiseSoil.Noise2D(float64(i)/float64(width)*10, float64(j)/float64(height)*10)
				if perlinSoil >= 0 {
					gameMap.tiles[i][j] = 2
				} else {
					gameMap.tiles[i][j] = 3
				}
			}

		}
	}
	gameMap.width = width
	gameMap.height = height
}

func (gameMap *GameMap) render(camera *sdl.Rect, surface *sdl.Surface) {
	fromX := camera.X
	fromY := camera.Y
	toX := camera.X + camera.W
	toY := camera.Y + camera.H
	for x := fromX; x < toX; x++ {
		for y := fromY; y < toY; y++ {
			cameraY := y - camera.Y
			cameraX := x - camera.X
			pixelColor := gameMap.getTileColor(x, y)
			surface.Set(int(cameraX), int(cameraY), pixelColor)

		}
	}
}

func (gameMap *GameMap) checkCollision(posX, posY int32) uint8 {
	//0 no collision
	//1 destructible collision
	//2 rock collision
	//3 indestructible collision
	if posX >= gameMap.width || posX < 0 || posY >= gameMap.height || posY < 0 {
		return 3
	}
	switch gameMap.tiles[posX][posY] {
	case 0:
		return 0
	case 1:
		return 2
	case 2:
		return 1
	case 3:
		return 1
	case 4:
		return 3
	case 5:
		return 3
	default:
		return 3
	}

}