/*

  This file is part of solidity.

  solidity is free software: you can redistribute it and/or modify

  it under the terms of the GNU General Public License as published by

  the Free Software Foundation, either version 3 of the License, or

  (at your option) any later version.

  solidity is distributed in the hope that it will be useful,

  but WITHOUT ANY WARRANTY; without even the implied warranty of

  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License

  along with solidity.  If not, see <http://www.gnu.org/licenses/>.

*/

// SPDX-License-Identifier: GPL-3.0

/**

 * @author Lefteris Karapetsas <lefteris@ethdev.com>

 * @date 2015

 * Represents a location in a source file

 */

#pragma once

#include <iosfwd>

#include <memory>

#include <string>

#include <tuple>

#include <vector>

namespace solidity::langutil

{

/**

 * Representation of an interval of source positions.

 * The interval includes start and excludes end.

 */

struct SourceLocation

{

  bool operator==(SourceLocation const& _other) const

  {

    return start == _other.start && end == _other.end && equalSources(_other);

  }

  bool operator!=(SourceLocation const& _other) const { return !operator==(_other); }

  bool operator<(SourceLocation const& _other) const

  {

    if (!sourceName || !_other.sourceName)

      return std::make_tuple(int(!!sourceName), start, end) < std::make_tuple(int(!!_other.sourceName), _other.start, _other.end);

    else

      return std::make_tuple(*sourceName, start, end) < std::make_tuple(*_other.sourceName, _other.start, _other.end);

  }

  bool contains(SourceLocation const& _other) const

  {

    if (!hasText() || !_other.hasText() || !equalSources(_other))

      return false;

    return start <= _other.start && _other.end <= end;

  }

  bool containsOffset(int _pos) const

  {

    if (!hasText() || _pos < 0)

      return false;

    return start <= _pos && _pos < end;

  }

  bool intersects(SourceLocation const& _other) const

  {

    if (!hasText() || !_other.hasText() || !equalSources(_other))

      return false;

    return _other.start < end && start < _other.end;

  }

  bool equalSources(SourceLocation const& _other) const

  {

    if (!!sourceName != !!_other.sourceName)

      return false;

    if (sourceName && *sourceName != *_other.sourceName)

      return false;

    return true;

  }

  bool isValid() const { return sourceName || start != -1 || end != -1; }

  bool hasText() const { return sourceName && 0 <= start && start <= end; }

  /// @returns the smallest SourceLocation that contains both @param _a and @param _b.

  /// Assumes that @param _a and @param _b refer to the same source (exception: if the source of either one

  /// is unset, the source of the other will be used for the result, even if that is unset as well).

  /// Invalid start and end positions (with value of -1) are ignored (if start or end are -1 for both @param _a and

  /// @param _b, then start resp. end of the result will be -1 as well).

  static SourceLocation smallestCovering(SourceLocation _a, SourceLocation const& _b)

  {

    if (!_a.sourceName)

      _a.sourceName = _b.sourceName;

    if (_a.start < 0)

      _a.start = _b.start;

    else if (_b.start >= 0 && _b.start < _a.start)

      _a.start = _b.start;

    if (_b.end > _a.end)

      _a.end = _b.end;

    return _a;

  }

  int start = -1;

  int end = -1;

  std::shared_ptr<std::string const> sourceName;

};

SourceLocation parseSourceLocation(

  std::string const& _input,

  std::vector<std::shared_ptr<std::string const>> const& _sourceNames

);

/// Stream output for Location (used e.g. in boost exceptions).

std::ostream& operator<<(std::ostream& _out, SourceLocation const& _location);

/**

 * Alternative, line-column-based representation for source locations.

 * Both line and column are zero-based.

 * If used as a range, the second location is considered exclusive.

 * Negative values are invalid.

 */

struct LineColumn

{

  /// Line value, can be between zero and number of `\n` characters in the source file.

  int line = -1;

  /// Column value, can be between zero and number of characters in the line (inclusive).

  int column = -1;

  LineColumn() = default;

  explicit LineColumn(int _line, int _column): line(_line), column(_column) {}

};

}