/* @jsx createElement */

'use strict';

import { Component, createElement, PropTypes } from 'rax';

const isWeb =
  typeof navigator === 'object' &&
  (navigator.appCodeName === 'Mozilla' || navigator.product === 'Gecko');

const WIDTH_ORIGINAL = 1;
const HEIGHT_ORIGINAL = 1;

/**
 * Image
 * @description  图片
 */
class Image extends Component {
  constructor(props) {
    super(props);
    this.state = {
      width: WIDTH_ORIGINAL,
      height: HEIGHT_ORIGINAL,
    };
    this.load = this.load.bind(this);
  }

  convertToRem(num) {
    let pxWidth;
    if (isWeb) {
      pxWidth = document.documentElement.clientWidth * devicePixelRatio;
    } else {
      pxWidth = WXEnvironment.deviceWidth;
    }
    return Math.round(num * 750 / pxWidth);
  }
  load(e) {
    let width;
    let height;
    if (!isWeb) {
      if (e.size && e.size.naturalWidth > 0 && e.size.naturalHeight > 0) {
        width = this.convertToRem(e.size.naturalWidth);
        height = this.convertToRem(e.size.naturalHeight);
      }
    } else if (e.target) {
      width = this.convertToRem(e.target.naturalWidth);
      height = this.convertToRem(e.target.naturalHeight);
      e.size = {
        naturalWidth: width,
        naturalHeight: height,
      };
    }
    if (this.props.autoFit && width && height) {
      this.setState({
        width,
        height,
      });
    }

    this.props.onLoad && this.props.onLoad(e);
  }
  render() {
    const {
      style,
      autoFit,
      src,
      source = {},
      resizeMode,
      onLoad,
      onPress,
      onClick,
      ...others
    } = this.props;

    const {
      uri,
      width: sourceWidth = WIDTH_ORIGINAL,
      height: sourceHeight = HEIGHT_ORIGINAL,
    } = source;
    if (!src && !uri) {
      return null;
    }
    let ImageElement;
    if (isWeb) {
      ImageElement = 'img';
    } else {
      ImageElement = 'image';
    }
    /**
     * compatible with source props
     */
    const nativeProps = {
      src: src || uri,
      quality: 'original',
      style: {
        width: autoFit ? this.state.width : sourceWidth,
        height: autoFit ? this.state.height : sourceHeight,
        ...style,
      },
      onLoad: this.load,
      ...others,
    };
    if (onPress || onClick) {
      nativeProps.onClick = onPress || onClick;
    }
    /**
     * if flex is defined, delete width 1, height 1
     */
    if (nativeProps.style.flex) {
      if (nativeProps.style.width === WIDTH_ORIGINAL) {
        delete nativeProps.style.width;
      }
      if (nativeProps.style.height === HEIGHT_ORIGINAL) {
        delete nativeProps.style.height;
      }
    }

    // for cover and contain
    const propsResizeMode = resizeMode || nativeProps.style.resizeMode;
    if (propsResizeMode) {
      if (isWeb) {
        delete nativeProps.style.flex;
        nativeProps.style.width = nativeProps.style.width || '100%';
        nativeProps.style.height = nativeProps.style.height || '100%';
        nativeProps.style.objectFit = propsResizeMode;
      } else {
        nativeProps.resize = propsResizeMode;
        nativeProps.style.resizeMode = propsResizeMode;
      }
    }

    return <ImageElement {...nativeProps} />;
  }
}

Image.propTypes = {
  /**
   * 资源地址 source url
   */
  src: PropTypes.string,
  /**
   * style 样式
   */
  style: PropTypes.object,
};
Image.defaultProps = {
  style: {},
  autoFit: false,
};
export default Image;