/*istanbul ignore start*/'use strict';

exports.__esModule = true;
exports. /*istanbul ignore end*/calcLineCount = calcLineCount;
/*istanbul ignore start*/exports. /*istanbul ignore end*/merge = merge;

var /*istanbul ignore start*/_create = require('./create') /*istanbul ignore end*/;

var /*istanbul ignore start*/_parse = require('./parse') /*istanbul ignore end*/;

var /*istanbul ignore start*/_array = require('../util/array') /*istanbul ignore end*/;

/*istanbul ignore start*/
function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }

/*istanbul ignore end*/function calcLineCount(hunk) {
  var conflicted = false;

  hunk.oldLines = 0;
  hunk.newLines = 0;

  hunk.lines.forEach(function (line) {
    if (typeof line !== 'string') {
      conflicted = true;
      return;
    }

    if (line[0] === '+' || line[0] === ' ') {
      hunk.newLines++;
    }
    if (line[0] === '-' || line[0] === ' ') {
      hunk.oldLines++;
    }
  });

  if (conflicted) {
    delete hunk.oldLines;
    delete hunk.newLines;
  }
}

function merge(mine, theirs, base) {
  mine = loadPatch(mine, base);
  theirs = loadPatch(theirs, base);

  var ret = {};

  // For index we just let it pass through as it doesn't have any necessary meaning.
  // Leaving sanity checks on this to the API consumer that may know more about the
  // meaning in their own context.
  if (mine.index || theirs.index) {
    ret.index = mine.index || theirs.index;
  }

  if (mine.newFileName || theirs.newFileName) {
    if (!fileNameChanged(mine)) {
      // No header or no change in ours, use theirs (and ours if theirs does not exist)
      ret.oldFileName = theirs.oldFileName || mine.oldFileName;
      ret.newFileName = theirs.newFileName || mine.newFileName;
      ret.oldHeader = theirs.oldHeader || mine.oldHeader;
      ret.newHeader = theirs.newHeader || mine.newHeader;
    } else if (!fileNameChanged(theirs)) {
      // No header or no change in theirs, use ours
      ret.oldFileName = mine.oldFileName;
      ret.newFileName = mine.newFileName;
      ret.oldHeader = mine.oldHeader;
      ret.newHeader = mine.newHeader;
    } else {
      // Both changed... figure it out
      ret.oldFileName = selectField(ret, mine.oldFileName, theirs.oldFileName);
      ret.newFileName = selectField(ret, mine.newFileName, theirs.newFileName);
      ret.oldHeader = selectField(ret, mine.oldHeader, theirs.oldHeader);
      ret.newHeader = selectField(ret, mine.newHeader, theirs.newHeader);
    }
  }

  ret.hunks = [];

  var mineIndex = 0,
      theirsIndex = 0,
      mineOffset = 0,
      theirsOffset = 0;

  while (mineIndex < mine.hunks.length || theirsIndex < theirs.hunks.length) {
    var mineCurrent = mine.hunks[mineIndex] || { oldStart: Infinity },
        theirsCurrent = theirs.hunks[theirsIndex] || { oldStart: Infinity };

    if (hunkBefore(mineCurrent, theirsCurrent)) {
      // This patch does not overlap with any of the others, yay.
      ret.hunks.push(cloneHunk(mineCurrent, mineOffset));
      mineIndex++;
      theirsOffset += mineCurrent.newLines - mineCurrent.oldLines;
    } else if (hunkBefore(theirsCurrent, mineCurrent)) {
      // This patch does not overlap with any of the others, yay.
      ret.hunks.push(cloneHunk(theirsCurrent, theirsOffset));
      theirsIndex++;
      mineOffset += theirsCurrent.newLines - theirsCurrent.oldLines;
    } else {
      // Overlap, merge as best we can
      var mergedHunk = {
        oldStart: Math.min(mineCurrent.oldStart, theirsCurrent.oldStart),
        oldLines: 0,
        newStart: Math.min(mineCurrent.newStart + mineOffset, theirsCurrent.oldStart + theirsOffset),
        newLines: 0,
        lines: []
      };
      mergeLines(mergedHunk, mineCurrent.oldStart, mineCurrent.lines, theirsCurrent.oldStart, theirsCurrent.lines);
      theirsIndex++;
      mineIndex++;

      ret.hunks.push(mergedHunk);
    }
  }

  return ret;
}

function loadPatch(param, base) {
  if (typeof param === 'string') {
    if (/^@@/m.test(param) || /^Index:/m.test(param)) {
      return (/*istanbul ignore start*/(0, _parse.parsePatch) /*istanbul ignore end*/(param)[0]
      );
    }

    if (!base) {
      throw new Error('Must provide a base reference or pass in a patch');
    }
    return (/*istanbul ignore start*/(0, _create.structuredPatch) /*istanbul ignore end*/(undefined, undefined, base, param)
    );
  }

  return param;
}

function fileNameChanged(patch) {
  return patch.newFileName && patch.newFileName !== patch.oldFileName;
}

function selectField(index, mine, theirs) {
  if (mine === theirs) {
    return mine;
  } else {
    index.conflict = true;
    return { mine: mine, theirs: theirs };
  }
}

function hunkBefore(test, check) {
  return test.oldStart < check.oldStart && test.oldStart + test.oldLines < check.oldStart;
}

function cloneHunk(hunk, offset) {
  return {
    oldStart: hunk.oldStart, oldLines: hunk.oldLines,
    newStart: hunk.newStart + offset, newLines: hunk.newLines,
    lines: hunk.lines
  };
}

function mergeLines(hunk, mineOffset, mineLines, theirOffset, theirLines) {
  // This will generally result in a conflicted hunk, but there are cases where the context
  // is the only overlap where we can successfully merge the content here.
  var mine = { offset: mineOffset, lines: mineLines, index: 0 },
      their = { offset: theirOffset, lines: theirLines, index: 0 };

  // Handle any leading content
  insertLeading(hunk, mine, their);
  insertLeading(hunk, their, mine);

  // Now in the overlap content. Scan through and select the best changes from each.
  while (mine.index < mine.lines.length && their.index < their.lines.length) {
    var mineCurrent = mine.lines[mine.index],
        theirCurrent = their.lines[their.index];

    if ((mineCurrent[0] === '-' || mineCurrent[0] === '+') && (theirCurrent[0] === '-' || theirCurrent[0] === '+')) {
      // Both modified ...
      mutualChange(hunk, mine, their);
    } else if (mineCurrent[0] === '+' && theirCurrent[0] === ' ') {
      /*istanbul ignore start*/
      var _hunk$lines;

      /*istanbul ignore end*/
      // Mine inserted
      /*istanbul ignore start*/(_hunk$lines = /*istanbul ignore end*/hunk.lines).push. /*istanbul ignore start*/apply /*istanbul ignore end*/( /*istanbul ignore start*/_hunk$lines /*istanbul ignore end*/, /*istanbul ignore start*/_toConsumableArray( /*istanbul ignore end*/collectChange(mine)));
    } else if (theirCurrent[0] === '+' && mineCurrent[0] === ' ') {
      /*istanbul ignore start*/
      var _hunk$lines2;

      /*istanbul ignore end*/
      // Theirs inserted
      /*istanbul ignore start*/(_hunk$lines2 = /*istanbul ignore end*/hunk.lines).push. /*istanbul ignore start*/apply /*istanbul ignore end*/( /*istanbul ignore start*/_hunk$lines2 /*istanbul ignore end*/, /*istanbul ignore start*/_toConsumableArray( /*istanbul ignore end*/collectChange(their)));
    } else if (mineCurrent[0] === '-' && theirCurrent[0] === ' ') {
      // Mine removed or edited
      removal(hunk, mine, their);
    } else if (theirCurrent[0] === '-' && mineCurrent[0] === ' ') {
      // Their removed or edited
      removal(hunk, their, mine, true);
    } else if (mineCurrent === theirCurrent) {
      // Context identity
      hunk.lines.push(mineCurrent);
      mine.index++;
      their.index++;
    } else {
      // Context mismatch
      conflict(hunk, collectChange(mine), collectChange(their));
    }
  }

  // Now push anything that may be remaining
  insertTrailing(hunk, mine);
  insertTrailing(hunk, their);

  calcLineCount(hunk);
}

function mutualChange(hunk, mine, their) {
  var myChanges = collectChange(mine),
      theirChanges = collectChange(their);

  if (allRemoves(myChanges) && allRemoves(theirChanges)) {
    // Special case for remove changes that are supersets of one another
    if ( /*istanbul ignore start*/(0, _array.arrayStartsWith) /*istanbul ignore end*/(myChanges, theirChanges) && skipRemoveSuperset(their, myChanges, myChanges.length - theirChanges.length)) {
      /*istanbul ignore start*/
      var _hunk$lines3;

      /*istanbul ignore end*/
      /*istanbul ignore start*/(_hunk$lines3 = /*istanbul ignore end*/hunk.lines).push. /*istanbul ignore start*/apply /*istanbul ignore end*/( /*istanbul ignore start*/_hunk$lines3 /*istanbul ignore end*/, /*istanbul ignore start*/_toConsumableArray( /*istanbul ignore end*/myChanges));
      return;
    } else if ( /*istanbul ignore start*/(0, _array.arrayStartsWith) /*istanbul ignore end*/(theirChanges, myChanges) && skipRemoveSuperset(mine, theirChanges, theirChanges.length - myChanges.length)) {
      /*istanbul ignore start*/
      var _hunk$lines4;

      /*istanbul ignore end*/
      /*istanbul ignore start*/(_hunk$lines4 = /*istanbul ignore end*/hunk.lines).push. /*istanbul ignore start*/apply /*istanbul ignore end*/( /*istanbul ignore start*/_hunk$lines4 /*istanbul ignore end*/, /*istanbul ignore start*/_toConsumableArray( /*istanbul ignore end*/theirChanges));
      return;
    }
  } else if ( /*istanbul ignore start*/(0, _array.arrayEqual) /*istanbul ignore end*/(myChanges, theirChanges)) {
    /*istanbul ignore start*/
    var _hunk$lines5;

    /*istanbul ignore end*/
    /*istanbul ignore start*/(_hunk$lines5 = /*istanbul ignore end*/hunk.lines).push. /*istanbul ignore start*/apply /*istanbul ignore end*/( /*istanbul ignore start*/_hunk$lines5 /*istanbul ignore end*/, /*istanbul ignore start*/_toConsumableArray( /*istanbul ignore end*/myChanges));
    return;
  }

  conflict(hunk, myChanges, theirChanges);
}

function removal(hunk, mine, their, swap) {
  var myChanges = collectChange(mine),
      theirChanges = collectContext(their, myChanges);
  if (theirChanges.merged) {
    /*istanbul ignore start*/
    var _hunk$lines6;

    /*istanbul ignore end*/
    /*istanbul ignore start*/(_hunk$lines6 = /*istanbul ignore end*/hunk.lines).push. /*istanbul ignore start*/apply /*istanbul ignore end*/( /*istanbul ignore start*/_hunk$lines6 /*istanbul ignore end*/, /*istanbul ignore start*/_toConsumableArray( /*istanbul ignore end*/theirChanges.merged));
  } else {
    conflict(hunk, swap ? theirChanges : myChanges, swap ? myChanges : theirChanges);
  }
}

function conflict(hunk, mine, their) {
  hunk.conflict = true;
  hunk.lines.push({
    conflict: true,
    mine: mine,
    theirs: their
  });
}

function insertLeading(hunk, insert, their) {
  while (insert.offset < their.offset && insert.index < insert.lines.length) {
    var line = insert.lines[insert.index++];
    hunk.lines.push(line);
    insert.offset++;
  }
}
function insertTrailing(hunk, insert) {
  while (insert.index < insert.lines.length) {
    var line = insert.lines[insert.index++];
    hunk.lines.push(line);
  }
}

function collectChange(state) {
  var ret = [],
      operation = state.lines[state.index][0];
  while (state.index < state.lines.length) {
    var line = state.lines[state.index];

    // Group additions that are immediately after subtractions and treat them as one "atomic" modify change.
    if (operation === '-' && line[0] === '+') {
      operation = '+';
    }

    if (operation === line[0]) {
      ret.push(line);
      state.index++;
    } else {
      break;
    }
  }

  return ret;
}
function collectContext(state, matchChanges) {
  var changes = [],
      merged = [],
      matchIndex = 0,
      contextChanges = false,
      conflicted = false;
  while (matchIndex < matchChanges.length && state.index < state.lines.length) {
    var change = state.lines[state.index],
        match = matchChanges[matchIndex];

    // Once we've hit our add, then we are done
    if (match[0] === '+') {
      break;
    }

    contextChanges = contextChanges || change[0] !== ' ';

    merged.push(match);
    matchIndex++;

    // Consume any additions in the other block as a conflict to attempt
    // to pull in the remaining context after this
    if (change[0] === '+') {
      conflicted = true;

      while (change[0] === '+') {
        changes.push(change);
        change = state.lines[++state.index];
      }
    }

    if (match.substr(1) === change.substr(1)) {
      changes.push(change);
      state.index++;
    } else {
      conflicted = true;
    }
  }

  if ((matchChanges[matchIndex] || '')[0] === '+' && contextChanges) {
    conflicted = true;
  }

  if (conflicted) {
    return changes;
  }

  while (matchIndex < matchChanges.length) {
    merged.push(matchChanges[matchIndex++]);
  }

  return {
    merged: merged,
    changes: changes
  };
}

function allRemoves(changes) {
  return changes.reduce(function (prev, change) {
    return prev && change[0] === '-';
  }, true);
}
function skipRemoveSuperset(state, removeChanges, delta) {
  for (var i = 0; i < delta; i++) {
    var changeContent = removeChanges[removeChanges.length - delta + i].substr(1);
    if (state.lines[state.index + i] !== ' ' + changeContent) {
      return false;
    }
  }

  state.index += delta;
  return true;
}
//# sourceMappingURL=data:application/json;base64,[encoded data, 26104 characters]
