import Phaser from 'phaser'
import { TILE_SIZE, WORLD_TILES } from '../config'
import { TileType, IMPASSABLE } from '../types'
import { stateManager } from '../StateManager'

const BIOME_COLORS: Record<number, string> = {
  0: '#1565C0',  // DEEP_WATER
  1: '#42A5F5',  // SHALLOW_WATER
  2: '#F5DEB3',  // SAND
  3: '#66BB6A',  // GRASS
  4: '#43A047',  // DARK_GRASS
  5: '#33691E',  // FOREST
  6: '#616161',  // ROCK
  // Built types: show grass below
  7: '#66BB6A', 8: '#66BB6A', 9: '#66BB6A', 10: '#66BB6A',
}

export class WorldSystem {
  private scene: Phaser.Scene
  private map!: Phaser.Tilemaps.Tilemap
  private tileset!: Phaser.Tilemaps.Tileset
  private bgImage!: Phaser.GameObjects.Image
  private builtLayer!: Phaser.Tilemaps.TilemapLayer

  constructor(scene: Phaser.Scene) {
    this.scene = scene
  }

  create(): void {
    const state = stateManager.getState()

    // --- Canvas background (1px per tile, scaled up, LINEAR filtered) ---
    const canvas = document.createElement('canvas')
    canvas.width = WORLD_TILES
    canvas.height = WORLD_TILES
    const ctx = canvas.getContext('2d')!

    for (let y = 0; y < WORLD_TILES; y++) {
      for (let x = 0; x < WORLD_TILES; x++) {
        const tile = state.world.tiles[y * WORLD_TILES + x]
        ctx.fillStyle = BIOME_COLORS[tile] ?? '#0a2210'
        ctx.fillRect(x, y, 1, 1)
      }
    }

    this.scene.textures.addCanvas('terrain_bg', canvas)
    this.bgImage = this.scene.add.image(0, 0, 'terrain_bg')
      .setOrigin(0, 0)
      .setScale(TILE_SIZE)
      .setDepth(0)
    this.scene.textures.get('terrain_bg').setFilter(Phaser.Textures.FilterMode.LINEAR)

    // --- Built tile layer (sparse — only FLOOR, WALL, TILLED_SOIL, WATERED_SOIL) ---
    this.map = this.scene.make.tilemap({
      tileWidth: TILE_SIZE,
      tileHeight: TILE_SIZE,
      width: WORLD_TILES,
      height: WORLD_TILES,
    })

    const ts = this.map.addTilesetImage('tiles', 'tiles', TILE_SIZE, TILE_SIZE, 0, 0, 0)
    if (!ts) throw new Error('Failed to add tileset')
    this.tileset = ts

    const layer = this.map.createBlankLayer('built', this.tileset, 0, 0)
    if (!layer) throw new Error('Failed to create built layer')
    this.builtLayer = layer
    this.builtLayer.setDepth(1)

    const BUILT_TILES = new Set([7, 8, 9, 10])  // FLOOR, WALL, TILLED_SOIL, WATERED_SOIL
    for (let y = 0; y < WORLD_TILES; y++) {
      for (let x = 0; x < WORLD_TILES; x++) {
        const t = state.world.tiles[y * WORLD_TILES + x]
        if (BUILT_TILES.has(t)) {
          this.builtLayer.putTileAt(t, x, y)
        }
      }
    }

    // Camera bounds
    this.scene.cameras.main.setBounds(0, 0, WORLD_TILES * TILE_SIZE, WORLD_TILES * TILE_SIZE)
  }

  getLayer(): Phaser.Tilemaps.TilemapLayer {
    return this.builtLayer
  }

  setTile(tileX: number, tileY: number, type: TileType): void {
    const BUILT_TILES = new Set([TileType.FLOOR, TileType.WALL, TileType.TILLED_SOIL, TileType.WATERED_SOIL])
    if (BUILT_TILES.has(type)) {
      this.builtLayer.putTileAt(type, tileX, tileY)
    } else {
      // Reverting to natural: remove from built layer
      this.builtLayer.removeTileAt(tileX, tileY)
    }
  }

  isPassable(tileX: number, tileY: number): boolean {
    if (tileX < 0 || tileY < 0 || tileX >= WORLD_TILES || tileY >= WORLD_TILES) return false
    const state = stateManager.getState()
    const tile = state.world.tiles[tileY * WORLD_TILES + tileX]
    return !IMPASSABLE.has(tile)
  }

  worldToTile(worldX: number, worldY: number): { tileX: number; tileY: number } {
    return {
      tileX: Math.floor(worldX / TILE_SIZE),
      tileY: Math.floor(worldY / TILE_SIZE),
    }
  }

  tileToWorld(tileX: number, tileY: number): { x: number; y: number } {
    return {
      x: tileX * TILE_SIZE + TILE_SIZE / 2,
      y: tileY * TILE_SIZE + TILE_SIZE / 2,
    }
  }

  getTileType(tileX: number, tileY: number): TileType {
    const state = stateManager.getState()
    return state.world.tiles[tileY * WORLD_TILES + tileX] as TileType
  }

  destroy(): void {
    this.map.destroy()
    this.bgImage.destroy()
  }
}