/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */

import { connect } from "../../utils/connect";
import PropTypes from "prop-types";
import { Component } from "react";
import { toEditorLine, fromEditorLine } from "../../utils/editor";
import { getBlackBoxRanges, getSelectedSource } from "../../selectors";

// This renders blackbox line highlighting in the editor
class BlackboxLines extends Component {
  static get propTypes() {
    return {
      editor: PropTypes.object,
      selectedSource: PropTypes.object,
      blackboxedRangesForSelectedSource: PropTypes.object,
    };
  }

  componentDidMount() {
    const {
      selectedSource,
      blackboxedRangesForSelectedSource,
      editor,
    } = this.props;

    // When `blackboxedRangesForSelectedSource` is undefined, the source isn't blackboxed
    if (!blackboxedRangesForSelectedSource) {
      return;
    }

    // But when `blackboxedRangesForSelectedSource` is defined and the array is empty,
    // the whole source was blackboxed.
    if (!blackboxedRangesForSelectedSource.length) {
      this.setAllBlackboxLines(editor);
    } else {
      editor.codeMirror.operation(() => {
        blackboxedRangesForSelectedSource.forEach(range => {
          const start = toEditorLine(selectedSource.id, range.start.line);
          const end = toEditorLine(selectedSource.id, range.end.line);
          editor.codeMirror.eachLine(start, end, lineHandle => {
            this.setBlackboxLine(editor, lineHandle);
          });
        });
      });
    }
  }

  componentDidUpdate() {
    const {
      selectedSource,
      blackboxedRangesForSelectedSource,
      editor,
    } = this.props;

    // when unblackboxed
    if (!blackboxedRangesForSelectedSource) {
      this.clearAllBlackboxLines(editor);
      return;
    }

    // When the whole source is blackboxed
    if (!blackboxedRangesForSelectedSource.length) {
      this.setAllBlackboxLines(editor);
      return;
    }

    // TODO: Possible perf improvement. Instead of going
    // over all the lines each time get diffs of what has
    // changed and update those.
    editor.codeMirror.operation(() => {
      editor.codeMirror.eachLine(lineHandle => {
        const line = fromEditorLine(
          selectedSource.id,
          editor.codeMirror.getLineNumber(lineHandle)
        );

        if (this.isLineBlackboxed(blackboxedRangesForSelectedSource, line)) {
          this.setBlackboxLine(editor, lineHandle);
        } else {
          this.clearBlackboxLine(editor, lineHandle);
        }
      });
    });
  }

  componentWillUnmount() {
    // Lets make sure we remove everything  relating to
    // blackboxing lines when this component is unmounted.
    this.clearAllBlackboxLines(this.props.editor);
  }

  isLineBlackboxed(ranges, line) {
    return !!ranges.find(
      range => line >= range.start.line && line <= range.end.line
    );
  }

  clearAllBlackboxLines(editor) {
    editor.codeMirror.operation(() => {
      editor.codeMirror.eachLine(lineHandle => {
        this.clearBlackboxLine(editor, lineHandle);
      });
    });
  }

  setAllBlackboxLines(editor) {
    //TODO:We might be able to handle the whole source
    // than adding the blackboxing line by line
    editor.codeMirror.operation(() => {
      editor.codeMirror.eachLine(lineHandle => {
        this.setBlackboxLine(editor, lineHandle);
      });
    });
  }

  clearBlackboxLine(editor, lineHandle) {
    editor.codeMirror.removeLineClass(
      lineHandle,
      "wrapClass",
      "blackboxed-line"
    );
  }

  setBlackboxLine(editor, lineHandle) {
    editor.codeMirror.addLineClass(lineHandle, "wrapClass", "blackboxed-line");
  }

  render() {
    return null;
  }
}

const mapStateToProps = state => {
  const selectedSource = getSelectedSource(state);
  return {
    selectedSource,
    blackboxedRangesForSelectedSource: selectedSource
      ? getBlackBoxRanges(state)[selectedSource.url]
      : undefined,
  };
};

export default connect(mapStateToProps)(BlackboxLines);