import React, {Component} from 'react';
import PropTypes from 'prop-types';
import WebView from 'react-native-webview';
import {MessageConverter} from './WebviewMessageHandler';
import {actions, messages} from './const';
import {Modal, View, Text, StyleSheet, TextInput, TouchableOpacity, Platform, PixelRatio, Keyboard, Dimensions} from 'react-native';

const PlatformIOS = Platform.OS === 'ios';

export default class RichTextEditor extends Component {
  static propTypes = {
    initialTitleHTML: PropTypes.string,
    initialContentHTML: PropTypes.string,
    titlePlaceholder: PropTypes.string,
    contentPlaceholder: PropTypes.string,
    editorInitializedCallback: PropTypes.func,
    customCSS: PropTypes.string,
    hiddenTitle: PropTypes.bool,
    enableOnChange: PropTypes.bool,
    footerHeight: PropTypes.number,
    contentInset: PropTypes.object
  };

  static defaultProps = {
    contentInset: {},
    style: {}
  };

  constructor(props) {
    super(props);
    this._sendAction = this._sendAction.bind(this);
    this.registerToolbar = this.registerToolbar.bind(this);
    this.onMessage = this.onMessage.bind(this);
    this._onKeyboardWillShow = this._onKeyboardWillShow.bind(this);
    this._onKeyboardWillHide = this._onKeyboardWillHide.bind(this);
    this.state = {
      selectionChangeListeners: [],
      onChange: [],
      isShowLinkDialog: false,
      linkInitialUrl: '',
      linkTitle: '',
      linkUrl: '',
      keyboardHeight: 0
    };
    this._selectedTextChangeListeners = [];
  }

  componentDidMount() {
    if(PlatformIOS) {
      this.keyboardEventListeners = [
        Keyboard.addListener('keyboardWillShow', this._onKeyboardWillShow),
        Keyboard.addListener('keyboardWillHide', this._onKeyboardWillHide)
      ];
    } else {
      this.keyboardEventListeners = [
        Keyboard.addListener('keyboardDidShow', this._onKeyboardWillShow),
        Keyboard.addListener('keyboardDidHide', this._onKeyboardWillHide)
      ];
      if (this.props.autoFocus) {
        this.webview.requestFocus();
      }
    }
  }

  componentWillUnmount() {
    this.keyboardEventListeners.forEach((eventListener) => eventListener.remove());
  }

  _onKeyboardWillShow(event) {
    const newKeyboardHeight = event.endCoordinates.height;
    if (this.state.keyboardHeight === newKeyboardHeight) {
      return;
    }
    if (newKeyboardHeight) {
      this.setEditorAvailableHeightBasedOnKeyboardHeight(newKeyboardHeight);
    }
    this.setState({keyboardHeight: newKeyboardHeight});
  }

  _onKeyboardWillHide(event) {
    this.setState({keyboardHeight: 0});
  }

  setEditorAvailableHeightBasedOnKeyboardHeight(keyboardHeight) {
    const {top = 0, bottom = 0} = this.props.contentInset;
    const {marginTop = 0, marginBottom = 0} = this.props.style;
    const {heightToScreenTop = 0} = this.props;
    const spacing = marginTop + marginBottom + top + bottom;

    const editorAvailableHeight = Dimensions.get('window').height - keyboardHeight - spacing - heightToScreenTop;
    this.setEditorHeight(editorAvailableHeight);
  }

  onMessage({ nativeEvent }){
    const { data: str } = nativeEvent;
    try {
      const message = JSON.parse(str);

      switch (message.type) {
        case messages.TITLE_HTML_RESPONSE:
          if (this.titleResolve) {
            this.titleResolve(message.data);
            this.titleResolve = undefined;
            this.titleReject = undefined;
            if (this.pendingTitleHtml) {
              clearTimeout(this.pendingTitleHtml);
              this.pendingTitleHtml = undefined;
            }
          }
          break;
        case messages.TITLE_TEXT_RESPONSE:
          if (this.titleTextResolve) {
            this.titleTextResolve(message.data);
            this.titleTextResolve = undefined;
            this.titleTextReject = undefined;
            if (this.pendingTitleText) {
              clearTimeout(this.pendingTitleText);
              this.pendingTitleText = undefined;
            }
          }
          break;
        case messages.CONTENT_HTML_RESPONSE:
          if (this.contentResolve) {
            this.contentResolve(message.data);
            this.contentResolve = undefined;
            this.contentReject = undefined;
            if (this.pendingContentHtml) {
              clearTimeout(this.pendingContentHtml);
              this.pendingContentHtml = undefined;
            }
          }
          break;
        case messages.SELECTED_TEXT_RESPONSE:
          if (this.selectedTextResolve) {
            this.selectedTextResolve(message.data);
            this.selectedTextResolve = undefined;
            this.selectedTextReject = undefined;
            if (this.pendingSelectedText) {
              clearTimeout(this.pendingSelectedText);
              this.pendingSelectedText = undefined;
            }
          }
          break;
        case messages.ZSS_INITIALIZED:
          if (this.props.customCSS) {
            this.setCustomCSS(this.props.customCSS);
          }
          this.setTitlePlaceholder(this.props.titlePlaceholder);
          this.setContentPlaceholder(this.props.contentPlaceholder);
          this.setTitleHTML(this.props.initialTitleHTML || '');
          this.setContentHTML(this.props.initialContentHTML || '');
          !this.props.hiddenTitle && this.showTitle();
          this.props.enableOnChange && this.enableOnChange();

          this.props.editorInitializedCallback && this.props.editorInitializedCallback();

          break;
        case messages.LINK_TOUCHED:
          const {title, url} = message.data;
          this.showLinkDialog(title, url);
          break;
        case messages.LOG:
          console.log('FROM ZSS', message.data);
          break;
        case messages.SCROLL:
          this.webview.setNativeProps({contentOffset: {y: message.data}});
          break;
        case messages.TITLE_FOCUSED:
          this.titleFocusHandler && this.titleFocusHandler();
          break;
        case messages.CONTENT_FOCUSED:
          this.contentFocusHandler && this.contentFocusHandler();
          break;
        case messages.CONTENT_BLUR:
          this.contentBlurHandler && this.contentBlurHandler();
          break;
        case messages.ONCHANGE_EMPTY_OR_NOT:
          this.onChangeEmptyOrNot && this.onChangeEmptyOrNot(message.isEmpty);
          break;
        case messages.SELECTION_CHANGE: {
          const items = message.data.items;
          this.state.selectionChangeListeners.map((listener) => {
            listener(items);
          });
          break;
        }
        case messages.CONTENT_CHANGE: {
          const content = message.data.content;
          this.state.onChange.map((listener) => listener(content));
          break;
        }
        case messages.SELECTED_TEXT_CHANGED: {
          const selectedText = message.data;
          this._selectedTextChangeListeners.forEach((listener) => {
            listener(selectedText);
          });
          break;
        }
      }
    } catch(e) {
      //alert('NON JSON MESSAGE');
    }
  }

  _renderLinkModal() {
    const {linkOption,optionalText} = this.props;
    return (
        <Modal
            animationType={"fade"}
            transparent
            visible={this.state.isShowLinkDialog}
            onRequestClose={() => this.setState({isShowLinkDialog: false})}
        >
          <View style={styles.modal}>
            <View style={[styles.innerModal, {marginBottom: PlatformIOS ? this.state.keyboardHeight : 0}]}>
              <Text style={styles.inputTitle}>{linkOption.titleText}</Text>
              <View style={styles.inputWrapper}>
                <TextInput
                  style={styles.input}
                  onChangeText={(text) => this.setState({linkTitle: text})}
                  value={this.state.linkTitle}
                  placeholder={optionalText}
                />
              </View>
              <Text style={[styles.inputTitle ,{marginTop: 10}]}>{linkOption.urlText}</Text>
              <View style={styles.inputWrapper}>
                <TextInput
                  style={styles.input}
                  onChangeText={(text) => this.setState({linkUrl: text})}
                  value={this.state.linkUrl}
                  keyboardType="url"
                  autoCapitalize="none"
                  autoCorrect={false}
                />
              </View>
              <View style={styles.lineSeparator}/>
              {this._renderModalButtons()}
            </View>
          </View>
        </Modal>
    );
  }

  _hideModal() {
    this.setState({
      isShowLinkDialog: false,
      linkInitialUrl: '',
      linkTitle: '',
      linkUrl: ''
    })
  }

  _renderModalButtons() {
    const insertUpdateDisabled = this.state.linkUrl.trim().length <= 0;
    const containerPlatformStyle = {justifyContent: 'space-between'};
    const buttonPlatformStyle = {flex: 1, height: 45, justifyContent: 'center'};
    const { linkOption } = this.props;
    return (
      <View style={{alignSelf: 'stretch', flexDirection: 'row', justifyContent: 'space-between'}}>
        <TouchableOpacity
            onPress={() => this._hideModal()}
            style={buttonPlatformStyle}
        >
          <Text style={[styles.button, {paddingRight: 10}]}>
            {linkOption.cancelText}
          </Text>
        </TouchableOpacity>
        <TouchableOpacity
            onPress={() => {
              if (this._linkIsNew()) {
                this.insertLink(this.state.linkUrl, this.state.linkTitle);
              } else {
                this.updateLink(this.state.linkUrl, this.state.linkTitle);
              }
              this._hideModal();
            }}
            disabled={insertUpdateDisabled}
            style={buttonPlatformStyle}
        >
          <Text style={[styles.button, {opacity: insertUpdateDisabled ? 0.5 : 1}]}>
            {this._linkIsNew() ? linkOption.insertText : linkOption.updateText}
          </Text>
        </TouchableOpacity>
      </View>
    );
  }

  _linkIsNew() {
    return !this.state.linkInitialUrl;
  }

  render() {
    //in release build, external html files in Android can't be required, so they must be placed in the assets folder and accessed via uri
    const pageSource = PlatformIOS ? require('./editor.html') : { uri: 'file:///android_asset/editor.html' };
    return (
      <View style={{flex: 1}}>
        <WebView
          {...this.props}
          hideKeyboardAccessoryView={true}
          keyboardDisplayRequiresUserAction={false}
          ref={(r) => {this.webview = r}}
          onMessage={(message) => this.onMessage(message)}
          source={pageSource}
          onLoad={() => this.init()}
        />
        {this._renderLinkModal()}
      </View>
    );
  }

  _sendAction(action, data) {
    let jsToBeExecutedOnPage = MessageConverter({ type: action, data });
    this.webview.injectJavaScript(jsToBeExecutedOnPage + ';true;');
  }

  //-------------------------------------------------------------------------------
  //--------------- Public API

  showLinkDialog(optionalTitle = '', optionalUrl = '', notCheckedUrlCallback) {
    this.notCheckedUrlCallback = notCheckedUrlCallback || this.notCheckedUrlCallback;
    this.prepareInsert();
    this.setState({
      linkInitialUrl: optionalUrl,
      linkTitle: optionalTitle,
      linkUrl: optionalUrl,
      isShowLinkDialog: true
    });
  }

  focusTitle() {
    this._sendAction(actions.focusTitle);
  }

  focusContent() {
    this._sendAction(actions.focusContent);
  }

  registerToolbar(listener) {
    this.setState({
      selectionChangeListeners: [...this.state.selectionChangeListeners, listener]
    });
  }

  enableOnChange() {
    this._sendAction(actions.enableOnChange);
  }

  registerContentChangeListener(listener) {
    this.setState({
      onChange: [...this.state.onChange, listener]
    });
  }

  setTitleHTML(html) {
    this._sendAction(actions.setTitleHtml, html);
  }
  hideTitle() {
    this._sendAction(actions.hideTitle);
  }
  showTitle() {
    this._sendAction(actions.showTitle);
  }
  toggleTitle() {
    this._sendAction(actions.toggleTitle);
  }
  setContentHTML(html) {
    this._sendAction(actions.setContentHtml, html);
  }

  blurTitleEditor() {
    this._sendAction(actions.blurTitleEditor);
  }

  blurContentEditor() {
    this._sendAction(actions.blurContentEditor);
  }

  setBold() {
    this._sendAction(actions.setBold);
  }

  setItalic() {
    this._sendAction(actions.setItalic);
  }

  setUnderline() {
    this._sendAction(actions.setUnderline);
  }

  heading1() {
    this._sendAction(actions.heading1);
  }

  heading2() {
    this._sendAction(actions.heading2);
  }

  heading3() {
    this._sendAction(actions.heading3);
  }

  heading4() {
    this._sendAction(actions.heading4);
  }

  heading5() {
    this._sendAction(actions.heading5);
  }

  heading6() {
    this._sendAction(actions.heading6);
  }

  setParagraph() {
    this._sendAction(actions.setParagraph);
  }

  removeFormat() {
    this._sendAction(actions.removeFormat);
  }

  alignLeft() {
    this._sendAction(actions.alignLeft);
  }

  alignCenter() {
    this._sendAction(actions.alignCenter);
  }

  alignRight() {
    this._sendAction(actions.alignRight);
  }

  alignFull() {
    this._sendAction(actions.alignFull);
  }

  insertBulletsList() {
    this._sendAction(actions.insertBulletsList);
  }

  insertOrderedList() {
    this._sendAction(actions.insertOrderedList);
  }

  insertLink(url, title) {
    // 不填写标题，则采用链接作为url
    title = title || url;
    // 如果前没有http://，则需要加入
    if (!(/^(http:\/\/|https:\/\/)/.test(url))) {
      url = `http://${url}`;
    }
    this._sendAction(actions.insertLink, {url, title});
    // if (/^(http:\/\/|https:\/\/)/.test(url)) {
    //   this._sendAction(actions.insertLink, {url, title: title || url});
    // } else {
    //   this.notCheckedUrlCallback && this.notCheckedUrlCallback()
    // }
  }

  updateLink(url, title) {
    // 不填写标题，则采用链接作为url
    title = title || url;
    // 如果前没有http://，则需要加入
    if (!(/^(http:\/\/|https:\/\/)/.test(url))) {
      url = `http://${url}`;
    }
    this._sendAction(actions.updateLink, {url, title});
    // if (/^(http:\/\/|https:\/\/)/.test(url)) {
    //   this._sendAction(actions.updateLink, {url, title: title || url});
    // } else {
    //   this.notCheckedUrlCallback && this.notCheckedUrlCallback()
    // }
  }

  insertImage(url) {
    this._sendAction(actions.insertImage, url);
  }

  insertEmoji(url, tag) {
    this._sendAction(actions.insertEmoji, { tag, url });
  }

  deleteEmoji(url) {
    this._sendAction(actions.deleteEmoji, url);
  }

  setSubscript() {
    this._sendAction(actions.setSubscript);
  }

  setSuperscript() {
    this._sendAction(actions.setSuperscript);
  }

  setStrikethrough() {
    this._sendAction(actions.setStrikethrough);
  }

  setHR() {
    this._sendAction(actions.setHR);
  }

  setIndent() {
    this._sendAction(actions.setIndent);
  }

  setOutdent() {
    this._sendAction(actions.setOutdent);
  }

  setBackgroundColor(color) {
    this._sendAction(actions.setBackgroundColor, color);
  }

  setTextColor(color) {
    this._sendAction(actions.setTextColor, color);
  }

  setTitlePlaceholder(placeholder) {
    this._sendAction(actions.setTitlePlaceholder, placeholder);
  }

  setContentPlaceholder(placeholder) {
    this._sendAction(actions.setContentPlaceholder, placeholder);
  }

  setCustomCSS(css) {
    this._sendAction(actions.setCustomCSS, css);
  }

  prepareInsert(showCaretPlaceholder) {
    this._sendAction(actions.prepareInsert, showCaretPlaceholder);
  }

  restoreSelection() {
    this._sendAction(actions.restoreSelection);
  }

  init() {
    this._sendAction(actions.init);
    this.setPlatform();
    if (this.props.footerHeight) {
      this.setFooterHeight();
    }
  }

  setEditorHeight(height) {
    this._sendAction(actions.setEditorHeight, height);
  }

  setFooterHeight() {
    this._sendAction(actions.setFooterHeight, this.props.footerHeight);
  }

  setPlatform() {
    this._sendAction(actions.setPlatform, Platform.OS);
  }

  async getTitleHtml() {
    return new Promise((resolve, reject) => {
      this.titleResolve = resolve;
      this.titleReject = reject;
      this._sendAction(actions.getTitleHtml);

      this.pendingTitleHtml = setTimeout(() => {
        if (this.titleReject) {
          this.titleReject('timeout')
        }
      }, 5000);
    });
  }

  async getTitleText() {
    return new Promise((resolve, reject) => {
      this.titleTextResolve = resolve;
      this.titleTextReject = reject;
      this._sendAction(actions.getTitleText);

      this.pendingTitleText = setTimeout(() => {
        if (this.titleTextReject) {
          this.titleTextReject('timeout');
        }
      }, 5000);
    });
  }

  async getContentHtml() {
    return new Promise((resolve, reject) => {
      this.contentResolve = resolve;
      this.contentReject = reject;
      this._sendAction(actions.getContentHtml);

      this.pendingContentHtml = setTimeout(() => {
        if (this.contentReject) {
          this.contentReject('timeout')
        }
      }, 5000);
    });
  }

  async getSelectedText() {
    return new Promise((resolve, reject) => {
      this.selectedTextResolve = resolve;
      this.selectedTextReject = reject;
      this._sendAction(actions.getSelectedText);

      this.pendingSelectedText = setTimeout(() => {
        if (this.selectedTextReject) {
          this.selectedTextReject('timeout')
        }
      }, 5000);
    });
  }

  setTitleFocusHandler(callbackHandler) {
    this.titleFocusHandler = callbackHandler;
    this._sendAction(actions.setTitleFocusHandler);
  }

  setContentFocusHandler(callbackHandler) {
    this.contentFocusHandler = callbackHandler;
    this._sendAction(actions.setContentFocusHandler);
  }

  setContentBlurHandler(callbackHandler) {
    this.contentBlurHandler = callbackHandler;
    this._sendAction(actions.setContentBlurHandler);
  }

  setOnChangeEmptyOrNot(callbackHandler) {
    this.onChangeEmptyOrNot = callbackHandler;
    this._sendAction(actions.setOnChangeEmptyOrNot);
  } 

  addSelectedTextChangeListener(listener) {
    this._selectedTextChangeListeners.push(listener);
  }
}

const styles = StyleSheet.create({
  modal: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: 'rgba(0, 0, 0, 0.5)'
  },
  innerModal: {
    backgroundColor: 'rgba(255, 255, 255, 0.9)',
    paddingTop: 20,
    paddingBottom: 0,
    paddingLeft: 20,
    paddingRight: 20,
    alignSelf: 'stretch',
    margin: 40,
    borderRadius: 8
  },
  button: {
    fontSize: 16,
    color: '#4a4a4a',
    textAlign: 'center'
  },
  inputWrapper: {
    marginTop: 5,
    marginBottom: 10,
    borderBottomColor: '#4a4a4a',
    borderBottomWidth: StyleSheet.hairlineWidth,
    justifyContent :'flex-end',
    height: 30,
    paddingBottom: 1,
  },
  inputTitle: {
    color: '#4a4a4a'
  },
  input: {
    padding: 0,
    margin: 0,
    includeFontPadding:false,
  },
  lineSeparator: {
    height: 1 / PixelRatio.get(),
    backgroundColor: '#d5d5d5',
    marginLeft: -20,
    marginRight: -20,
    marginTop: 15
  }
});