// Originally from linkify: https://github.com/Cretezy/linkify/blob/dfb3e43b0e56452bad584ddb0bf9b73d8db0589f/lib/src/url.dart
//
// Removed handling of `removeWWW` and `humanize`.
// Removed auto-appending of `http(s)://` to the readable url
//
// MIT License
//
// Copyright (c) 2019 Charles-William Crete
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

import 'linkify.dart';

final _urlRegex = RegExp(
  r'^(.*?)((?:https?:\/\/|www\.)[^\s/$.?#].[^\s]*)',
  caseSensitive: false,
  dotAll: true,
);

final _looseUrlRegex = RegExp(
  r'^(.*?)((https?:\/\/)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,4}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*))',
  caseSensitive: false,
  dotAll: true,
);

final _protocolIdentifierRegex = RegExp(
  r'^(https?:\/\/)',
  caseSensitive: false,
);

class UrlLinkifier extends Linkifier {
  const UrlLinkifier();

  @override
  List<LinkifyElement> parse(elements, options) {
    final list = <LinkifyElement>[];

    elements.forEach((element) {
      if (element is TextElement) {
        var match = options.looseUrl ? _looseUrlRegex.firstMatch(element.text) : _urlRegex.firstMatch(element.text);

        if (match == null) {
          list.add(element);
        } else {
          final text = element.text.replaceFirst(match.group(0)!, '');

          if (match.group(1)?.isNotEmpty == true) {
            list.add(TextElement(match.group(1)!));
          }

          if (match.group(2)?.isNotEmpty == true) {
            var originalUrl = match.group(2)!;
            String? end;

            if ((options.excludeLastPeriod) && originalUrl[originalUrl.length - 1] == ".") {
              end = ".";
              originalUrl = originalUrl.substring(0, originalUrl.length - 1);
            }

            var url = originalUrl;

            // If protocol has not been specified then append a protocol
            // to the start of the URL so that it can be opened...
            if (!url.startsWith("https://") && !url.startsWith("http://")) {
              url = "https://" + url;
            }

            list.add(UrlElement(url, originalUrl));

            if (end != null) {
              list.add(TextElement(end));
            }
          }

          if (text.isNotEmpty) {
            list.addAll(parse([TextElement(text)], options));
          }
        }
      } else {
        list.add(element);
      }
    });

    return list;
  }
}

/// Represents an element containing a link
class UrlElement extends LinkableElement {
  UrlElement(String url, [String? text]) : super(text, url);

  @override
  String toString() {
    return "LinkElement: '$url' ($text)";
  }

  @override
  bool operator ==(other) => equals(other);

  @override
  bool equals(other) => other is UrlElement && super.equals(other);
}