import 'package:flutter_test/flutter_test.dart';
import 'package:frosty/constants.dart';
import 'package:frosty/models/irc.dart';

import '../fixtures/irc_messages.dart';

void main() {
  group('IRCMessage.fromString', () {
    group('basic parsing', () {
      test('parses basic chat message correctly', () {
        final msg = IRCMessage.fromString(basicPrivmsg);

        expect(msg.user, 'testuser');
        expect(msg.message, 'Hello World');
        expect(msg.command, Command.privateMessage);
        expect(msg.tags['display-name'], 'TestUser');
        expect(msg.tags['color'], '#FF0000');
        expect(msg.tags['user-id'], '67890');
        expect(msg.tags['room-id'], '12345');
      });

      test('parses message with escaped spaces in tags', () {
        final msg = IRCMessage.fromString(messageWithEscapedSpaces);

        // \\s should be converted to actual space
        expect(msg.tags['badge-info'], 'subscriber/12 months');
        expect(msg.message, 'test message');
      });

      test('unescapes the full IRCv3 tag escape set', () {
        final msg = IRCMessage.fromString(messageWithEscapedTagChars);

        expect(msg.tags['a-space'], 'one two');
        expect(msg.tags['a-semi'], 'left;right');
        expect(msg.tags['a-slash'], r'a\b');
        // Only the first '=' splits key/value; later '=' stays in the value.
        expect(msg.tags['a-equals'], 'k=v');
        // `\\` consumes both backslashes; the following 's' is a literal letter,
        // not a `\s` space escape (single-pass unescaping).
        expect(msg.tags['a-double'], r'x\sy');
      });

      test('falls back to login tag when prefix has no "!"', () {
        // An unexpected prefix shape must not throw and drop the message.
        final msg = IRCMessage.fromString(messageNoBangPrefix);

        expect(msg.user, 'fallbackuser');
        expect(msg.message, 'server style');
      });

      test('handles message with no color tag', () {
        final msg = IRCMessage.fromString(messageNoColor);

        // Tags with empty values are skipped during parsing
        expect(msg.tags['color'], isNull);
        expect(msg.user, 'nocolor');
      });

      test('splits message into words correctly', () {
        final msg = IRCMessage.fromString(basicPrivmsg);

        expect(msg.split, ['Hello', 'World']);
      });
    });

    group('command detection', () {
      test('identifies PRIVMSG command', () {
        final msg = IRCMessage.fromString(basicPrivmsg);
        expect(msg.command, Command.privateMessage);
      });

      test('identifies CLEARCHAT command for user ban', () {
        final msg = IRCMessage.fromString(clearChatUser);
        expect(msg.command, Command.clearChat);
        expect(msg.message, 'banneduser');
        expect(msg.tags['ban-duration'], '600');
      });

      test('identifies CLEARCHAT command for full chat clear', () {
        final msg = IRCMessage.fromString(clearChatAll);
        expect(msg.command, Command.clearChat);
        expect(msg.message, isNull);
      });

      test('identifies CLEARMSG command', () {
        final msg = IRCMessage.fromString(clearMsg);
        expect(msg.command, Command.clearMessage);
        expect(msg.tags['target-msg-id'], 'target-msg-abc123');
      });

      test('identifies NOTICE command', () {
        final msg = IRCMessage.fromString(noticeMessage);
        expect(msg.command, Command.notice);
        expect(msg.tags['msg-id'], 'slow_on');
      });

      test('identifies USERNOTICE command', () {
        final msg = IRCMessage.fromString(userNoticeSubscription);
        expect(msg.command, Command.userNotice);
        expect(msg.tags['msg-id'], 'sub');
      });

      test('identifies ROOMSTATE command', () {
        final msg = IRCMessage.fromString(roomState);
        expect(msg.command, Command.roomState);
        expect(msg.tags['slow'], '0');
        expect(msg.tags['emote-only'], '0');
      });

      test('identifies USERSTATE command', () {
        final msg = IRCMessage.fromString(userState);
        expect(msg.command, Command.userState);
        expect(msg.tags['mod'], '0');
      });

      test('identifies GLOBALUSERSTATE command', () {
        final msg = IRCMessage.fromString(globalUserState);
        expect(msg.command, Command.globalUserState);
      });
    });

    group('emote parsing', () {
      test('extracts local emotes from emote tag', () {
        final msg = IRCMessage.fromString(privmsgWithEmotes);

        expect(msg.localEmotes, isNotNull);
        expect(msg.localEmotes!.containsKey('Kappa'), isTrue);
        expect(msg.localEmotes!.containsKey('LUL'), isTrue);

        // Verify emote URLs are constructed correctly
        expect(
          msg.localEmotes!['Kappa']!.url,
          contains('static-cdn.jtvnw.net/emoticons/v2/25'),
        );
      });

      test('handles multiple instances of same emote', () {
        final msg = IRCMessage.fromString(privmsgWithMultipleEmotes);

        // Should still only have one entry in localEmotes map
        expect(msg.localEmotes!.length, 1);
        expect(msg.localEmotes!['Kappa'], isNotNull);
      });

      test('handles message with no emotes', () {
        final msg = IRCMessage.fromString(basicPrivmsg);

        expect(msg.localEmotes, isEmpty);
      });
    });

    group('IRC action (/me) detection', () {
      test('detects /me action messages', () {
        final msg = IRCMessage.fromString(actionMessage);

        expect(msg.action, isTrue);
        expect(msg.message, 'is testing');
        // Action prefix and suffix should be stripped
        expect(msg.message, isNot(contains('\x01')));
      });

      test('non-action messages have action=false', () {
        final msg = IRCMessage.fromString(basicPrivmsg);
        expect(msg.action, isFalse);
      });
    });

    group('mention detection', () {
      test('detects when message mentions logged-in user', () {
        final msg = IRCMessage.fromString(
          mentionMessage,
          userLogin: 'targetuser',
        );

        expect(msg.mention, isTrue);
      });

      test('mention detection lowercases the message', () {
        // Note: The code lowercases the message but compares against userLogin as-is
        // So userLogin should be provided in lowercase for proper matching
        final msg = IRCMessage.fromString(
          mentionMessage,
          userLogin: 'targetuser', // lowercase to match the lowercased message
        );

        expect(msg.mention, isTrue);
      });

      test('no mention when user is not mentioned', () {
        final msg = IRCMessage.fromString(
          basicPrivmsg,
          userLogin: 'someotheruser',
        );

        expect(msg.mention, isFalse);
      });

      test('mention is false when userLogin not provided', () {
        final msg = IRCMessage.fromString(basicPrivmsg);
        expect(msg.mention, isFalse);
      });
    });

    group('Unicode handling', () {
      test('removes invalid Unicode characters', () {
        final msg = IRCMessage.fromString(messageWithInvalidUnicode);

        // The invalid Unicode character should be stripped
        expect(msg.message, 'HelloWorld');
        expect(msg.message, isNot(contains('\u{E0000}')));
      });

      test('handles emoji characters correctly', () {
        final msg = IRCMessage.fromString(messageWithEmoji);

        expect(msg.message, contains('😀'));
        expect(msg.message, contains('🎉'));
        // Emojis should be separated into their own entries in split
        expect(msg.split!.any((s) => s.contains('😀')), isTrue);
      });
    });

    group('reply message handling', () {
      test('parses reply message tags', () {
        final msg = IRCMessage.fromString(replyMessage);

        expect(msg.tags['reply-parent-display-name'], 'OriginalUser');
        expect(msg.tags['reply-parent-msg-id'], 'original-123');
        expect(msg.tags['reply-parent-user-login'], 'originaluser');
      });
    });

    group('special message types', () {
      test('parses moderator message', () {
        final msg = IRCMessage.fromString(moderatorMessage);

        expect(msg.tags['mod'], '1');
        expect(msg.tags['badges'], contains('moderator'));
      });

      test('parses historical message', () {
        final msg = IRCMessage.fromString(historicalMessage);

        expect(msg.tags['historical'], '1');
      });

      test('parses historical message with bare (valueless) tags', () {
        // The recent-messages API serializes empty tags as bare keys (e.g.
        // `emotes`, `flags`) instead of `key=`. This previously threw a
        // RangeError, silently dropping all recent messages.
        final msg = IRCMessage.fromString(historicalMessageBareTags);

        expect(msg.tags['historical'], '1');
        expect(msg.tags['display-name'], 'BareUser');
        expect(msg.message, 'Bare tag message');
        // Bare tags should be absent from the map, not crash parsing.
        expect(msg.tags.containsKey('emotes'), isFalse);
        expect(msg.tags.containsKey('flags'), isFalse);
      });

      test('parses shared chat message with source room', () {
        final msg = IRCMessage.fromString(sharedChatMessage);

        expect(msg.tags['source-room-id'], '99999');
        expect(msg.tags['room-id'], '12345');
      });

      test('parses message with URL in split', () {
        final msg = IRCMessage.fromString(messageWithUrl);

        expect(msg.message, contains('https://twitch.tv/channel'));
        expect(msg.split, isNotNull);
        expect(
          msg.split!.any((word) => regexLink.hasMatch(word)),
          isTrue,
        );
      });
    });
  });

  group('IRCMessage.clearChat', () {
    late List<IRCMessage> messages;
    late List<IRCMessage> bufferedMessages;

    setUp(() {
      // Create test messages from different users
      messages = [
        IRCMessage.fromString(basicPrivmsg), // from testuser
        IRCMessage.fromString(moderatorMessage), // from moduser
        IRCMessage.fromString(
          basicPrivmsg.replaceAll('testuser', 'user2').replaceAll('TestUser', 'User2'),
        ), // from user2
      ];
      bufferedMessages = [];
    });

    test('marks all messages from banned user', () {
      // Create a CLEARCHAT message targeting testuser
      final clearChatMsg = IRCMessage(
        raw: '',
        command: Command.clearChat,
        tags: {'ban-duration': '600'},
        message: 'testuser',
      );

      IRCMessage.clearChat(
        messages: messages,
        bufferedMessages: bufferedMessages,
        ircMessage: clearChatMsg,
      );

      // testuser's message should be marked as clearChat
      expect(
        messages.where((m) => m.user == 'testuser').first.command,
        Command.clearChat,
      );
      // Other users' messages should be unchanged
      expect(
        messages.where((m) => m.user == 'moduser').first.command,
        Command.privateMessage,
      );
    });

    test('adds ban-duration tag to affected messages', () {
      final clearChatMsg = IRCMessage(
        raw: '',
        command: Command.clearChat,
        tags: {'ban-duration': '300'},
        message: 'testuser',
      );

      IRCMessage.clearChat(
        messages: messages,
        bufferedMessages: bufferedMessages,
        ircMessage: clearChatMsg,
      );

      final affectedMessage = messages.where((m) => m.user == 'testuser').first;
      expect(affectedMessage.tags['ban-duration'], '300');
    });

    test('clears entire chat when no target user', () {
      final clearAllMsg = IRCMessage(
        raw: '',
        command: Command.clearChat,
        tags: {},
      );

      IRCMessage.clearChat(
        messages: messages,
        bufferedMessages: bufferedMessages,
        ircMessage: clearAllMsg,
      );

      // Messages list should be cleared and contain only the notice
      expect(messages.length, 1);
      expect(messages.first.command, Command.notice);
      expect(messages.first.message, 'Chat was cleared by a moderator');
    });
  });

  group('IRCMessage.clearMessage', () {
    late List<IRCMessage> messages;
    late List<IRCMessage> bufferedMessages;

    setUp(() {
      messages = [
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {'id': 'msg-1'},
          user: 'user1',
          message: 'Message 1',
        ),
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {'id': 'msg-2'},
          user: 'user2',
          message: 'Message 2',
        ),
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {'id': 'msg-3'},
          user: 'user1',
          message: 'Message 3',
        ),
      ];
      bufferedMessages = [];
    });

    test('marks specific message by ID', () {
      final clearMsg = IRCMessage(
        raw: '',
        command: Command.clearMessage,
        tags: {'target-msg-id': 'msg-2'},
      );

      IRCMessage.clearMessage(
        messages: messages,
        bufferedMessages: bufferedMessages,
        ircMessage: clearMsg,
      );

      // Only msg-2 should be marked
      expect(
        messages.firstWhere((m) => m.tags['id'] == 'msg-2').command,
        Command.clearMessage,
      );
      // Other messages unchanged
      expect(
        messages.firstWhere((m) => m.tags['id'] == 'msg-1').command,
        Command.privateMessage,
      );
      expect(
        messages.firstWhere((m) => m.tags['id'] == 'msg-3').command,
        Command.privateMessage,
      );
    });

    test('handles non-existent message ID gracefully', () {
      final clearMsg = IRCMessage(
        raw: '',
        command: Command.clearMessage,
        tags: {'target-msg-id': 'non-existent'},
      );

      // Should not throw
      expect(
        () => IRCMessage.clearMessage(
          messages: messages,
          bufferedMessages: bufferedMessages,
          ircMessage: clearMsg,
        ),
        returnsNormally,
      );

      // All messages should be unchanged
      expect(
        messages.every((m) => m.command == Command.privateMessage),
        isTrue,
      );
    });
  });

  group('IRCMessage.createNotice', () {
    test('creates notice message with correct properties', () {
      final notice = IRCMessage.createNotice(message: 'Test notice');

      expect(notice.command, Command.notice);
      expect(notice.message, 'Test notice');
      expect(notice.raw, isEmpty);
      expect(notice.tags, contains('tmi-sent-ts'));
      expect(notice.tags.length, 1);
    });

    test('creates notice with action callback', () {
      var called = false;
      final notice = IRCMessage.createNotice(
        message: 'Test',
        actionCallback: () => called = true,
        actionLabel: 'Retry',
      );

      expect(notice.actionCallback, isNotNull);
      expect(notice.actionLabel, 'Retry');
      notice.actionCallback!();
      expect(called, isTrue);
    });
  });

  group('ROOMSTATE', () {
    test('creates default ROOMSTATE', () {
      const roomstate = ROOMSTATE();

      expect(roomstate.emoteOnly, '0');
      expect(roomstate.followersOnly, '-1');
      expect(roomstate.r9k, '0');
      expect(roomstate.slowMode, '0');
      expect(roomstate.subMode, '0');
    });

    test('updates from IRC message', () {
      const original = ROOMSTATE();
      final ircMsg = IRCMessage(
        raw: '',
        command: Command.roomState,
        tags: {
          'emote-only': '1',
          'followers-only': '10',
          'slow': '30',
        },
      );

      final updated = original.fromIRCMessage(ircMsg);

      expect(updated.emoteOnly, '1');
      expect(updated.followersOnly, '10');
      expect(updated.slowMode, '30');
      // Unchanged values should keep original
      expect(updated.r9k, '0');
      expect(updated.subMode, '0');
    });
  });

  group('IRCMessage.clearChat — buffered messages', () {
    test('marks buffered messages from banned user', () {
      final messages = <IRCMessage>[];
      final bufferedMessages = [
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {'id': 'buf-1'},
          user: 'banneduser',
          message: 'Buffered msg',
        ),
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {'id': 'buf-2'},
          user: 'innocentuser',
          message: 'Other msg',
        ),
      ];

      final clearChatMsg = IRCMessage(
        raw: '',
        command: Command.clearChat,
        tags: {'ban-duration': '600'},
        message: 'banneduser',
      );

      IRCMessage.clearChat(
        messages: messages,
        bufferedMessages: bufferedMessages,
        ircMessage: clearChatMsg,
      );

      expect(bufferedMessages[0].command, Command.clearChat);
      expect(bufferedMessages[0].tags['ban-duration'], '600');
      expect(bufferedMessages[1].command, Command.privateMessage);
    });

    test('full chat clear also clears buffered messages', () {
      final messages = [
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {},
          message: 'msg',
        ),
      ];
      final bufferedMessages = [
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {},
          message: 'buffered',
        ),
      ];

      final clearAllMsg = IRCMessage(
        raw: '',
        command: Command.clearChat,
        tags: {},
      );

      IRCMessage.clearChat(
        messages: messages,
        bufferedMessages: bufferedMessages,
        ircMessage: clearAllMsg,
      );

      expect(bufferedMessages, isEmpty);
    });
  });

  group('IRCMessage.clearMessage — buffered messages', () {
    test('marks buffered message by ID', () {
      final messages = <IRCMessage>[];
      final bufferedMessages = [
        IRCMessage(
          raw: '',
          command: Command.privateMessage,
          tags: {'id': 'buf-target'},
          user: 'someuser',
          message: 'To be deleted',
        ),
      ];

      final clearMsg = IRCMessage(
        raw: '',
        command: Command.clearMessage,
        tags: {'target-msg-id': 'buf-target'},
      );

      IRCMessage.clearMessage(
        messages: messages,
        bufferedMessages: bufferedMessages,
        ircMessage: clearMsg,
      );

      expect(bufferedMessages.first.command, Command.clearMessage);
    });
  });

  group('IRCMessage edge cases', () {
    test('parses message with empty body', () {
      final msg = IRCMessage.fromString(messageEmptyBody);

      expect(msg.command, Command.privateMessage);
      // Empty trailing content after the colon
      expect(msg.message, isEmpty);
    });

    test('parses emote-only message', () {
      final msg = IRCMessage.fromString(messageOnlyEmotes);

      expect(msg.command, Command.privateMessage);
      expect(msg.message, 'Kappa Kappa');
      expect(msg.localEmotes, isNotNull);
      expect(msg.localEmotes!.containsKey('Kappa'), isTrue);
    });

    test('returns Command.none for a truncated line without a command', () {
      // A malformed/truncated line (e.g. from the recent-messages history API)
      // whose message section is a single token used to throw a RangeError on
      // splitMessage[1]. It must now parse safely as a none command.
      final msg = IRCMessage.fromString('@historical=1 :justaprefix');

      expect(msg.command, Command.none);
      expect(msg.tags['historical'], '1');
    });

    test('returns Command.none for a line with no separating space', () {
      // No space means there are no tags to slice and no body to parse; must
      // not throw on the substring/split calls.
      final msg = IRCMessage.fromString('@onlytags');

      expect(msg.command, Command.none);
    });
  });

  group('USERSTATE', () {
    test('creates default USERSTATE', () {
      const userstate = USERSTATE();

      expect(userstate.color, '');
      expect(userstate.displayName, '');
      expect(userstate.mod, isFalse);
      expect(userstate.subscriber, isFalse);
    });

    test('updates from IRC message', () {
      const original = USERSTATE();
      final ircMsg = IRCMessage(
        raw: '@color=#FF0000;display-name=TestUser;mod=1;subscriber=1',
        command: Command.userState,
        tags: {
          'color': '#FF0000',
          'display-name': 'TestUser',
          'mod': '1',
          'subscriber': '1',
        },
      );

      final updated = original.fromIRCMessage(ircMsg);

      expect(updated.color, '#FF0000');
      expect(updated.displayName, 'TestUser');
      expect(updated.mod, isTrue);
      expect(updated.subscriber, isTrue);
    });

    test('mod=0 is false', () {
      const original = USERSTATE();
      final ircMsg = IRCMessage(
        raw: '',
        command: Command.userState,
        tags: {'mod': '0'},
      );

      final updated = original.fromIRCMessage(ircMsg);
      expect(updated.mod, isFalse);
    });

    test('missing mod and subscriber tags are false', () {
      const original = USERSTATE();
      final ircMsg = IRCMessage(
        raw: '',
        command: Command.userState,
        tags: {'display-name': 'TestUser'},
      );

      final updated = original.fromIRCMessage(ircMsg);
      expect(updated.mod, isFalse);
      expect(updated.subscriber, isFalse);
    });
  });
}