'use strict';

Object.defineProperty(exports, '__esModule', {
  value: true
});
exports.default = void 0;

var _chalk = _interopRequireDefault(require('chalk'));

var _diffSequences = _interopRequireDefault(require('diff-sequences'));

var _constants = require('./constants');

function _interopRequireDefault(obj) {
  return obj && obj.__esModule ? obj : {default: obj};
}

/**
 * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
const DIFF_CONTEXT_DEFAULT = 5;
const fgPatchMark = _chalk.default.yellow;
const fgDelete = _chalk.default.green;
const fgInsert = _chalk.default.red;
const fgCommon = _chalk.default.dim; // common lines (even indentation same)

const fgIndent = _chalk.default.cyan; // common lines (only indentation different)

const bgCommon = _chalk.default.bgYellow; // edge spaces in common line (even indentation same)

const bgInverse = _chalk.default.inverse; // edge spaces in any other lines
// ONLY trailing if expected value is snapshot or multiline string.

const highlightTrailingSpaces = (line, bgColor) =>
  line.replace(/\s+$/, bgColor('$&')); // BOTH leading AND trailing if expected value is data structure.

const highlightLeadingTrailingSpaces = (
  line,
  bgColor // If line consists of ALL spaces: highlight all of them.
) =>
  highlightTrailingSpaces(line, bgColor).replace(
    // If line has an ODD length of leading spaces: highlight only the LAST.
    /^(\s\s)*(\s)(?=[^\s])/,
    '$1' + bgColor('$2')
  );

const getHighlightSpaces = bothEdges =>
  bothEdges ? highlightLeadingTrailingSpaces : highlightTrailingSpaces;

const getAnnotation = options =>
  fgDelete('- ' + ((options && options.aAnnotation) || 'Expected')) +
  '\n' +
  fgInsert('+ ' + ((options && options.bAnnotation) || 'Received')) +
  '\n\n';

// Given index interval in expected lines, put formatted delete lines.
const formatDelete = (aStart, aEnd, aLinesUn, aLinesIn, put) => {
  const highlightSpaces = getHighlightSpaces(aLinesUn !== aLinesIn);

  for (let aIndex = aStart; aIndex !== aEnd; aIndex += 1) {
    const aLineUn = aLinesUn[aIndex];
    const aLineIn = aLinesIn[aIndex];
    const indentation = aLineIn.slice(0, aLineIn.length - aLineUn.length);
    put(fgDelete('- ' + indentation + highlightSpaces(aLineUn, bgInverse)));
  }
}; // Given index interval in received lines, put formatted insert lines.

const formatInsert = (bStart, bEnd, bLinesUn, bLinesIn, put) => {
  const highlightSpaces = getHighlightSpaces(bLinesUn !== bLinesIn);

  for (let bIndex = bStart; bIndex !== bEnd; bIndex += 1) {
    const bLineUn = bLinesUn[bIndex];
    const bLineIn = bLinesIn[bIndex];
    const indentation = bLineIn.slice(0, bLineIn.length - bLineUn.length);
    put(fgInsert('+ ' + indentation + highlightSpaces(bLineUn, bgInverse)));
  }
}; // Given the number of items and starting indexes of a common subsequence,
// put formatted common lines.

const formatCommon = (
  nCommon,
  aCommon,
  bCommon,
  aLinesIn,
  bLinesUn,
  bLinesIn,
  put
) => {
  const highlightSpaces = getHighlightSpaces(bLinesUn !== bLinesIn);

  for (; nCommon !== 0; nCommon -= 1, aCommon += 1, bCommon += 1) {
    const bLineUn = bLinesUn[bCommon];
    const bLineIn = bLinesIn[bCommon];
    const bLineInLength = bLineIn.length; // For common lines, received indentation seems more intuitive.

    const indentation = bLineIn.slice(0, bLineInLength - bLineUn.length); // Color shows whether expected and received line has same indentation.

    const hasSameIndentation = aLinesIn[aCommon].length === bLineInLength;
    const fg = hasSameIndentation ? fgCommon : fgIndent;
    const bg = hasSameIndentation ? bgCommon : bgInverse;
    put(fg('  ' + indentation + highlightSpaces(bLineUn, bg)));
  }
}; // jest --expand
// Return formatted diff as joined string of all lines.

const diffExpand = (aLinesUn, bLinesUn, aLinesIn, bLinesIn) => {
  const isCommon = (aIndex, bIndex) => aLinesUn[aIndex] === bLinesUn[bIndex];

  const array = [];

  const put = line => {
    array.push(line);
  };

  let aStart = 0;
  let bStart = 0;

  const foundSubsequence = (nCommon, aCommon, bCommon) => {
    formatDelete(aStart, aCommon, aLinesUn, aLinesIn, put);
    formatInsert(bStart, bCommon, bLinesUn, bLinesIn, put);
    formatCommon(nCommon, aCommon, bCommon, aLinesIn, bLinesUn, bLinesIn, put);
    aStart = aCommon + nCommon;
    bStart = bCommon + nCommon;
  };

  const aLength = aLinesUn.length;
  const bLength = bLinesUn.length;
  (0, _diffSequences.default)(aLength, bLength, isCommon, foundSubsequence); // After the last common subsequence, format remaining change lines.

  formatDelete(aStart, aLength, aLinesUn, aLinesIn, put);
  formatInsert(bStart, bLength, bLinesUn, bLinesIn, put);
  return array.join('\n');
}; // In GNU diff format, indexes are one-based instead of zero-based.

const createPatchMark = (aStart, aEnd, bStart, bEnd) =>
  fgPatchMark(
    `@@ -${aStart + 1},${aEnd - aStart} +${bStart + 1},${bEnd - bStart} @@`
  );

const getContextLines = options =>
  options &&
  typeof options.contextLines === 'number' &&
  options.contextLines >= 0
    ? options.contextLines
    : DIFF_CONTEXT_DEFAULT; // jest --no-expand
// Return joined string of formatted diff for all change lines,
// but if some common lines are omitted because there are more than the context,
// then a “patch mark” precedes each set of adjacent changed and common lines.

const diffNoExpand = (
  aLinesUn,
  bLinesUn,
  aLinesIn,
  bLinesIn,
  nContextLines
) => {
  const isCommon = (aIndex, bIndex) => aLinesUn[aIndex] === bLinesUn[bIndex];

  let iPatchMark = 0; // index of placeholder line for patch mark

  const array = [''];

  const put = line => {
    array.push(line);
  };

  let isAtEnd = false;
  const aLength = aLinesUn.length;
  const bLength = bLinesUn.length;
  const nContextLines2 = nContextLines + nContextLines; // Initialize the first patch for changes at the start,
  // especially for edge case in which there is no common subsequence.

  let aStart = 0;
  let aEnd = 0;
  let bStart = 0;
  let bEnd = 0; // Given the number of items and starting indexes of each common subsequence,
  // format any preceding change lines, and then common context lines.

  const foundSubsequence = (nCommon, aStartCommon, bStartCommon) => {
    const aEndCommon = aStartCommon + nCommon;
    const bEndCommon = bStartCommon + nCommon;
    isAtEnd = aEndCommon === aLength && bEndCommon === bLength; // If common subsequence is at start, re-initialize the first patch.

    if (aStartCommon === 0 && bStartCommon === 0) {
      const nLines = nContextLines < nCommon ? nContextLines : nCommon;
      aStart = aEndCommon - nLines;
      bStart = bEndCommon - nLines;
      formatCommon(nLines, aStart, bStart, aLinesIn, bLinesUn, bLinesIn, put);
      aEnd = aEndCommon;
      bEnd = bEndCommon;
      return;
    } // Format preceding change lines.

    formatDelete(aEnd, aStartCommon, aLinesUn, aLinesIn, put);
    formatInsert(bEnd, bStartCommon, bLinesUn, bLinesIn, put);
    aEnd = aStartCommon;
    bEnd = bStartCommon; // If common subsequence is at end, then context follows preceding changes;
    // else context follows preceding changes AND precedes following changes.

    const maxContextLines = isAtEnd ? nContextLines : nContextLines2;

    if (nCommon <= maxContextLines) {
      // The patch includes all lines in the common subsequence.
      formatCommon(nCommon, aEnd, bEnd, aLinesIn, bLinesUn, bLinesIn, put);
      aEnd += nCommon;
      bEnd += nCommon;
      return;
    } // The patch ends because context is less than number of common lines.

    formatCommon(nContextLines, aEnd, bEnd, aLinesIn, bLinesUn, bLinesIn, put);
    aEnd += nContextLines;
    bEnd += nContextLines;
    array[iPatchMark] = createPatchMark(aStart, aEnd, bStart, bEnd); // If common subsequence is not at end, another patch follows it.

    if (!isAtEnd) {
      iPatchMark = array.length; // index of placeholder line

      array[iPatchMark] = '';
      const nLines = nContextLines < nCommon ? nContextLines : nCommon;
      aStart = aEndCommon - nLines;
      bStart = bEndCommon - nLines;
      formatCommon(nLines, aStart, bStart, aLinesIn, bLinesUn, bLinesIn, put);
      aEnd = aEndCommon;
      bEnd = bEndCommon;
    }
  };

  (0, _diffSequences.default)(aLength, bLength, isCommon, foundSubsequence); // If no common subsequence or last was not at end, format remaining change lines.

  if (!isAtEnd) {
    formatDelete(aEnd, aLength, aLinesUn, aLinesIn, put);
    formatInsert(bEnd, bLength, bLinesUn, bLinesIn, put);
    aEnd = aLength;
    bEnd = bLength;
  }

  if (aStart === 0 && aEnd === aLength && bStart === 0 && bEnd === bLength) {
    array.splice(0, 1); // delete placeholder line for patch mark
  } else {
    array[iPatchMark] = createPatchMark(aStart, aEnd, bStart, bEnd);
  }

  return array.join('\n');
};

var _default = (a, b, options, original) => {
  if (a === b) {
    return _constants.NO_DIFF_MESSAGE;
  }

  let aLinesUn = a.split('\n');
  let bLinesUn = b.split('\n'); // Indentation is unknown if expected value is snapshot or multiline string.

  let aLinesIn = aLinesUn;
  let bLinesIn = bLinesUn;

  if (original) {
    // Indentation is known if expected value is data structure:
    // Compare lines without indentation and format lines with indentation.
    aLinesIn = original.a.split('\n');
    bLinesIn = original.b.split('\n');

    if (
      aLinesUn.length !== aLinesIn.length ||
      bLinesUn.length !== bLinesIn.length
    ) {
      // Fall back if unindented and indented lines are inconsistent.
      aLinesUn = aLinesIn;
      bLinesUn = bLinesIn;
    }
  }

  return (
    getAnnotation(options) +
    (options && options.expand === false
      ? diffNoExpand(
          aLinesUn,
          bLinesUn,
          aLinesIn,
          bLinesIn,
          getContextLines(options)
        )
      : diffExpand(aLinesUn, bLinesUn, aLinesIn, bLinesIn))
  );
};

exports.default = _default;