import { Vector2D } from './Vector2D.js';

export class Input {
  constructor(canvas, viewport) {
    this.keys = new Set();
    this.pressed = new Set();
    this.mouse = new Vector2D(viewport.width / 2, viewport.height / 2);
    this.mouseDown = false;
    this.mouseClicked = false;
    this.viewport = viewport;
    this.isMobile = 'ontouchstart' in window || navigator.maxTouchPoints > 0;
    this.joystickActive = false;
    this.joystickTouchId = null;
    this.joystickBasePos = { x: 0, y: 0 };
    this.joystickRadius = 60;

    window.addEventListener('keydown', (event) => {
      this.keys.add(event.key.toLowerCase());
      if (!event.repeat) {
        this.pressed.add(event.key.toLowerCase());
      }
      if (event.key === ' ') {
        event.preventDefault();
        if (
          document.activeElement &&
          document.activeElement.tagName === 'BUTTON' &&
          typeof document.activeElement.blur === 'function'
        ) {
          document.activeElement.blur();
        }
      }
    });
    window.addEventListener('keyup', (event) => {
      this.keys.delete(event.key.toLowerCase());
    });
    window.addEventListener('blur', () => {
      this.keys.clear();
      this.pressed.clear();
      this.mouseDown = false;
    });

    canvas.addEventListener('mousemove', (event) => {
      const rect = canvas.getBoundingClientRect();
      this.mouse.x = ((event.clientX - rect.left) / rect.width) * viewport.width;
      this.mouse.y = ((event.clientY - rect.top) / rect.height) * viewport.height;
    });
    canvas.addEventListener('mousedown', (event) => {
      if (event.button === 0) {
        this.mouseDown = true;
        this.mouseClicked = true;
      }
    });
    window.addEventListener('mouseup', () => {
      this.mouseDown = false;
    });

    if (this.isMobile) {
      this._initTouchJoystick(canvas);
    }
  }

  _initTouchJoystick(canvas) {
    this.joystickBaseEl = document.createElement('div');
    this.joystickBaseEl.className = 'joystick-base';
    this.joystickBaseEl.style.display = 'none';

    this.joystickThumbEl = document.createElement('div');
    this.joystickThumbEl.className = 'joystick-thumb';
    this.joystickThumbEl.style.display = 'none';

    document.body.appendChild(this.joystickBaseEl);
    document.body.appendChild(this.joystickThumbEl);

    canvas.addEventListener('touchstart', (event) => this._handleTouchStart(event), { passive: false });
    canvas.addEventListener('touchmove', (event) => this._handleTouchMove(event), { passive: false });
    canvas.addEventListener('touchend', (event) => this._handleTouchEnd(event), { passive: false });
    canvas.addEventListener('touchcancel', (event) => this._handleTouchEnd(event), { passive: false });
  }

  _handleTouchStart(event) {
    event.preventDefault();
    for (const touch of event.changedTouches) {
      const x = touch.clientX;
      if (x < this.viewport.width / 2 && !this.joystickActive) {
        this.joystickActive = true;
        this.joystickTouchId = touch.identifier;
        this.joystickBasePos.x = x;
        this.joystickBasePos.y = touch.clientY;

        this.joystickBaseEl.style.left = `${x}px`;
        this.joystickBaseEl.style.top = `${this.joystickBasePos.y}px`;
        this.joystickBaseEl.style.display = 'block';
        this.joystickThumbEl.style.left = `${x}px`;
        this.joystickThumbEl.style.top = `${this.joystickBasePos.y}px`;
        this.joystickThumbEl.style.display = 'block';
      }
    }
  }

  _handleTouchMove(event) {
    event.preventDefault();
    for (const touch of event.changedTouches) {
      if (touch.identifier !== this.joystickTouchId) continue;
      const dx = touch.clientX - this.joystickBasePos.x;
      const dy = touch.clientY - this.joystickBasePos.y;
      const dist = Math.sqrt(dx * dx + dy * dy);
      let clampedDx = dx;
      let clampedDy = dy;
      if (dist > this.joystickRadius) {
        clampedDx = (dx / dist) * this.joystickRadius;
        clampedDy = (dy / dist) * this.joystickRadius;
      }

      this.joystickThumbEl.style.left = `${this.joystickBasePos.x + clampedDx}px`;
      this.joystickThumbEl.style.top = `${this.joystickBasePos.y + clampedDy}px`;

      const deadZone = 12;
      this.keys.delete('w');
      this.keys.delete('a');
      this.keys.delete('s');
      this.keys.delete('d');
      if (dy < -deadZone) this.keys.add('w');
      if (dy > deadZone) this.keys.add('s');
      if (dx < -deadZone) this.keys.add('a');
      if (dx > deadZone) this.keys.add('d');
    }
  }

  _handleTouchEnd(event) {
    for (const touch of event.changedTouches) {
      if (touch.identifier === this.joystickTouchId) {
        this.joystickActive = false;
        this.joystickTouchId = null;
        this.keys.delete('w');
        this.keys.delete('a');
        this.keys.delete('s');
        this.keys.delete('d');
        this.joystickBaseEl.style.display = 'none';
        this.joystickThumbEl.style.display = 'none';
      }
    }
  }

  clearPressed() {
    this.pressed.clear();
    this.mouseClicked = false;
  }
}