import Phaser from 'phaser'
import { WORLD_TILES } from '../config'
import { stateManager } from '../StateManager'
import type { LocalAdapter } from '../NetworkAdapter'

const CAMERA_SPEED = 400  // px/s
const MIN_ZOOM = 0.25
const MAX_ZOOM = 2.0
const ZOOM_STEP = 0.1

export class CameraSystem {
  private scene: Phaser.Scene
  private adapter: LocalAdapter
  private keys!: {
    up: Phaser.Input.Keyboard.Key
    down: Phaser.Input.Keyboard.Key
    left: Phaser.Input.Keyboard.Key
    right: Phaser.Input.Keyboard.Key
    w: Phaser.Input.Keyboard.Key
    s: Phaser.Input.Keyboard.Key
    a: Phaser.Input.Keyboard.Key
    d: Phaser.Input.Keyboard.Key
  }
  private saveTimer = 0
  private readonly SAVE_TICK = 2000
  private middlePanActive = false
  private lastPanX = 0
  private lastPanY = 0
  private debugCross?: Phaser.GameObjects.Graphics

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

  create(): void {
    const state = stateManager.getState()
    const cam = this.scene.cameras.main

    // Start at saved player position (reused as camera anchor)
    cam.scrollX = state.player.x - cam.width / 2
    cam.scrollY = state.player.y - cam.height / 2

    const kb = this.scene.input.keyboard!
    this.keys = {
      up:    kb.addKey(Phaser.Input.Keyboard.KeyCodes.UP),
      down:  kb.addKey(Phaser.Input.Keyboard.KeyCodes.DOWN),
      left:  kb.addKey(Phaser.Input.Keyboard.KeyCodes.LEFT),
      right: kb.addKey(Phaser.Input.Keyboard.KeyCodes.RIGHT),
      w:     kb.addKey(Phaser.Input.Keyboard.KeyCodes.W),
      s:     kb.addKey(Phaser.Input.Keyboard.KeyCodes.S),
      a:     kb.addKey(Phaser.Input.Keyboard.KeyCodes.A),
      d:     kb.addKey(Phaser.Input.Keyboard.KeyCodes.D),
    }

    // Debug cross at viewport center (fixed to screen, not world)
    this.debugCross = this.scene.add.graphics()
    this.debugCross.setScrollFactor(0).setDepth(999)
    this.debugCross.lineStyle(2, 0xff0000, 1)
    const cx = cam.width / 2
    const cy = cam.height / 2
    this.debugCross.lineBetween(cx - 12, cy, cx + 12, cy)
    this.debugCross.lineBetween(cx, cy - 12, cx, cy + 12)

    // Scroll wheel zoom
    this.scene.input.on('wheel', (ptr: Phaser.Input.Pointer, _objs: unknown, _dx: number, dy: number) => {
      const newZoom = Phaser.Math.Clamp(cam.zoom - Math.sign(dy) * ZOOM_STEP, MIN_ZOOM, MAX_ZOOM)
      cam.setZoom(newZoom)
      const centerX = cam.scrollX + cam.width  / (2 * cam.zoom)
      const centerY = cam.scrollY + cam.height / (2 * cam.zoom)
      console.log(`[zoom] ptr.x=${ptr.x.toFixed(0)} ptr.y=${ptr.y.toFixed(0)} | ptr.worldX=${ptr.worldX.toFixed(0)} ptr.worldY=${ptr.worldY.toFixed(0)} | center=(${centerX.toFixed(0)}, ${centerY.toFixed(0)}) zoom=${cam.zoom.toFixed(2)}`)
    })

    // Middle-click pan: start on button down
    this.scene.input.on('pointerdown', (ptr: Phaser.Input.Pointer) => {
      if (ptr.middleButtonDown()) {
        this.middlePanActive = true
        this.lastPanX = ptr.x
        this.lastPanY = ptr.y
      }
    })

    // Middle-click pan: move camera while held
    this.scene.input.on('pointermove', (ptr: Phaser.Input.Pointer) => {
      if (!this.middlePanActive) return
      const dx = (ptr.x - this.lastPanX) / cam.zoom
      const dy = (ptr.y - this.lastPanY) / cam.zoom
      cam.scrollX -= dx
      cam.scrollY -= dy
      this.lastPanX = ptr.x
      this.lastPanY = ptr.y
    })

    // Middle-click pan: stop on button release
    this.scene.input.on('pointerup', (ptr: Phaser.Input.Pointer) => {
      if (this.middlePanActive && !ptr.middleButtonDown()) {
        this.middlePanActive = false
      }
    })
  }

  update(delta: number): void {
    const cam = this.scene.cameras.main
    const speed = CAMERA_SPEED * (delta / 1000) / cam.zoom

    const up    = this.keys.up.isDown    || this.keys.w.isDown
    const down  = this.keys.down.isDown  || this.keys.s.isDown
    const left  = this.keys.left.isDown  || this.keys.a.isDown
    const right = this.keys.right.isDown || this.keys.d.isDown

    let dx = 0, dy = 0
    if (left)  dx -= speed
    if (right) dx += speed
    if (up)    dy -= speed
    if (down)  dy += speed

    if (dx !== 0 && dy !== 0) { dx *= 0.707; dy *= 0.707 }

    const worldW = WORLD_TILES * 32  // TILE_SIZE hardcoded since WORLD_PX may not exist
    const worldH = WORLD_TILES * 32
    cam.scrollX = Phaser.Math.Clamp(cam.scrollX + dx, 0, worldW - cam.width / cam.zoom)
    cam.scrollY = Phaser.Math.Clamp(cam.scrollY + dy, 0, worldH - cam.height / cam.zoom)

    // Periodically save camera center as "player position"
    this.saveTimer += delta
    if (this.saveTimer >= this.SAVE_TICK) {
      this.saveTimer = 0
      this.adapter.send({
        type: 'PLAYER_MOVE',
        x: cam.scrollX + cam.width / 2,
        y: cam.scrollY + cam.height / 2,
      })
    }
  }

  getCenterWorld(): { x: number; y: number } {
    const cam = this.scene.cameras.main
    return {
      x: cam.scrollX + cam.width / (2 * cam.zoom),
      y: cam.scrollY + cam.height / (2 * cam.zoom),
    }
  }

  getCenterTile(): { tileX: number; tileY: number } {
    const { x, y } = this.getCenterWorld()
    return { tileX: Math.floor(x / 32), tileY: Math.floor(y / 32) }
  }
}