import { computeBoxProps } from './Box';
import { Stack } from './Stack';
import { ProgressBar } from './ProgressBar';
import { Button } from './Button';
import { Component } from 'inferno';

const ZOOM_MIN_VAL = 0.5;
const ZOOM_MAX_VAL = 1.5;

const ZOOM_INCREMENT = 0.1;

export class InfinitePlane extends Component {
  constructor() {
    super();

    this.state = {
      mouseDown: false,

      left: 0,
      top: 0,

      lastLeft: 0,
      lastTop: 0,

      zoom: 1,
    };

    this.handleMouseDown = this.handleMouseDown.bind(this);
    this.handleMouseMove = this.handleMouseMove.bind(this);
    this.handleZoomIncrease = this.handleZoomIncrease.bind(this);
    this.handleZoomDecrease = this.handleZoomDecrease.bind(this);
    this.onMouseUp = this.onMouseUp.bind(this);

    this.doOffsetMouse = this.doOffsetMouse.bind(this);
  }

  componentDidMount() {
    window.addEventListener('mouseup', this.onMouseUp);

    window.addEventListener('mousedown', this.doOffsetMouse);
    window.addEventListener('mousemove', this.doOffsetMouse);
    window.addEventListener('mouseup', this.doOffsetMouse);
  }

  componentWillUnmount() {
    window.removeEventListener('mouseup', this.onMouseUp);

    window.removeEventListener('mousedown', this.doOffsetMouse);
    window.removeEventListener('mousemove', this.doOffsetMouse);
    window.removeEventListener('mouseup', this.doOffsetMouse);
  }

  doOffsetMouse(event) {
    const { zoom } = this.state;
    event.screenZoomX = event.screenX * Math.pow(zoom, -1);
    event.screenZoomY = event.screenY * Math.pow(zoom, -1);
  }

  handleMouseDown(event) {
    this.setState((state) => {
      return {
        mouseDown: true,
        lastLeft: event.clientX - state.left,
        lastTop: event.clientY - state.top,
      };
    });
  }

  onMouseUp() {
    this.setState({
      mouseDown: false,
    });
  }

  handleZoomIncrease(event) {
    const { onZoomChange } = this.props;
    const { zoom } = this.state;
    const newZoomValue = Math.min(zoom + ZOOM_INCREMENT, ZOOM_MAX_VAL);
    this.setState({
      zoom: newZoomValue,
    });
    if (onZoomChange) {
      onZoomChange(newZoomValue);
    }
  }

  handleZoomDecrease(event) {
    const { onZoomChange } = this.props;
    const { zoom } = this.state;
    const newZoomValue = Math.max(zoom - ZOOM_INCREMENT, ZOOM_MIN_VAL);
    this.setState({
      zoom: newZoomValue,
    });

    if (onZoomChange) {
      onZoomChange(newZoomValue);
    }
  }

  handleMouseMove(event) {
    const { onBackgroundMoved, initialLeft = 0, initialTop = 0 } = this.props;
    if (this.state.mouseDown) {
      let newX, newY;
      this.setState((state) => {
        newX = event.clientX - state.lastLeft;
        newY = event.clientY - state.lastTop;
        return {
          left: newX,
          top: newY,
        };
      });
      if (onBackgroundMoved) {
        onBackgroundMoved(newX + initialLeft, newY + initialTop);
      }
    }
  }

  render() {
    const {
      children,
      backgroundImage,
      imageWidth,
      initialLeft = 0,
      initialTop = 0,
      ...rest
    } = this.props;
    const { left, top, zoom } = this.state;

    const finalLeft = initialLeft + left;
    const finalTop = initialTop + top;

    return (
      <div
        ref={this.ref}
        {...computeBoxProps({
          ...rest,
          style: {
            ...rest.style,
            overflow: 'hidden',
            position: 'relative',
          },
        })}>
        <div
          onMouseDown={this.handleMouseDown}
          onMouseMove={this.handleMouseMove}
          style={{
            'position': 'fixed',
            'height': '100%',
            'width': '100%',
            'background-image': `url("${backgroundImage}")`,
            'background-position': `${finalLeft}px ${finalTop}px`,
            'background-repeat': 'repeat',
            'background-size': `${zoom * imageWidth}px`,
          }}
        />
        <div
          onMouseDown={this.handleMouseDown}
          onMouseMove={this.handleMouseMove}
          style={{
            'position': 'fixed',
            'transform': `translate(${finalLeft}px, ${finalTop}px) scale(${zoom})`,
            'transform-origin': 'top left',
            'height': '100%',
            'width': '100%',
          }}>
          {children}
        </div>

        <Stack position="absolute" width="100%">
          <Stack.Item>
            <Button icon="minus" onClick={this.handleZoomDecrease} />
          </Stack.Item>
          <Stack.Item grow={1}>
            <ProgressBar
              minValue={ZOOM_MIN_VAL}
              value={zoom}
              maxValue={ZOOM_MAX_VAL}>
              {zoom}x
            </ProgressBar>
          </Stack.Item>
          <Stack.Item>
            <Button icon="plus" onClick={this.handleZoomIncrease} />
          </Stack.Item>
        </Stack>
      </div>
    );
  }
}