import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import '../../models/log_entry.dart';
import '../../providers/session_provider.dart';
import '../../theme/app_theme.dart';
import 'widgets/assistant_message_card.dart';
import 'widgets/system_message_card.dart';
import 'widgets/user_message_card.dart';

class TimelineScreen extends StatelessWidget {
  const TimelineScreen({super.key});

  @override
  Widget build(BuildContext context) {
    final provider = context.watch<SessionProvider>();
    final session = provider.session;
    if (session == null) {
      return const Center(
        child: Text('No session loaded', style: TextStyle(color: AppColors.textMuted)),
      );
    }

    final entries = provider.filteredEntries;

    return Scaffold(
      backgroundColor: AppColors.background,
      body: Column(
        children: [
          _FilterBar(provider: provider),
          Expanded(
            child: entries.isEmpty
                ? const Center(
                    child: Text('No matching entries',
                        style: TextStyle(color: AppColors.textMuted)),
                  )
                : ListView.builder(
                    padding: const EdgeInsets.fromLTRB(24, 8, 24, 24),
                    itemCount: entries.length,
                    itemBuilder: (context, index) {
                      return _buildEntryCard(entries[index], index);
                    },
                  ),
          ),
        ],
      ),
    );
  }

  Widget _buildEntryCard(LogEntry entry, int index) {
    if (entry is UserEntry && !entry.isToolResult) {
      return Padding(
        padding: const EdgeInsets.only(bottom: 8),
        child: UserMessageCard(entry: entry, index: index),
      );
    }
    if (entry is AssistantEntry) {
      return Padding(
        padding: const EdgeInsets.only(bottom: 8),
        child: AssistantMessageCard(entry: entry, index: index),
      );
    }
    if (entry is SystemEntry) {
      return Padding(
        padding: const EdgeInsets.only(bottom: 8),
        child: SystemMessageCard(entry: entry),
      );
    }
    return const SizedBox.shrink();
  }
}

class _FilterBar extends StatelessWidget {
  final SessionProvider provider;

  const _FilterBar({required this.provider});

  @override
  Widget build(BuildContext context) {
    final session = provider.session!;

    return Container(
      padding: const EdgeInsets.fromLTRB(24, 16, 24, 12),
      decoration: const BoxDecoration(
        color: AppColors.surface,
        border: Border(
          bottom: BorderSide(color: AppColors.surfaceBorder, width: 1),
        ),
      ),
      child: Row(
        children: [
          // Session info
          Expanded(
            child: Row(
              children: [
                Text(
                  session.sessionId?.substring(0, 8) ?? 'Session',
                  style: const TextStyle(
                    fontSize: 14,
                    fontWeight: FontWeight.w600,
                    color: AppColors.textPrimary,
                  ),
                ),
                const SizedBox(width: 12),
                if (session.version != null)
                  _InfoChip(label: 'v${session.version}'),
                const SizedBox(width: 8),
                _InfoChip(
                    label: '${provider.filteredEntries.length} entries'),
                const SizedBox(width: 8),
                _InfoChip(
                    label:
                        '${_formatTokens(session.totalUsage.totalTokens)} tokens'),
              ],
            ),
          ),
          // Agent filter
          if (session.agents.length > 1) ...[
            const SizedBox(width: 12),
            Container(
              padding: const EdgeInsets.symmetric(horizontal: 8),
              decoration: BoxDecoration(
                color: AppColors.surfaceLight,
                borderRadius: BorderRadius.circular(6),
                border: Border.all(color: AppColors.surfaceBorder),
              ),
              child: DropdownButtonHideUnderline(
                child: DropdownButton<String?>(
                  value: provider.selectedAgentId,
                  isDense: true,
                  dropdownColor: AppColors.surfaceLight,
                  style: const TextStyle(
                      fontSize: 12, color: AppColors.textPrimary),
                  hint: const Text('All Agents',
                      style: TextStyle(
                          fontSize: 12, color: AppColors.textSecondary)),
                  items: [
                    const DropdownMenuItem(
                      value: null,
                      child: Text('All Agents'),
                    ),
                    ...session.agents.map((a) => DropdownMenuItem(
                          value: a.id,
                          child: Text(a.name,
                              overflow: TextOverflow.ellipsis),
                        )),
                  ],
                  onChanged: (v) => provider.selectAgent(v),
                ),
              ),
            ),
          ],
          const SizedBox(width: 12),
          // Type toggles
          _TypeToggle(
            label: 'User',
            color: AppColors.user,
            active: provider.visibleTypes.contains('user'),
            onTap: () => provider.toggleTypeFilter('user'),
          ),
          const SizedBox(width: 4),
          _TypeToggle(
            label: 'Assistant',
            color: AppColors.assistant,
            active: provider.visibleTypes.contains('assistant'),
            onTap: () => provider.toggleTypeFilter('assistant'),
          ),
          const SizedBox(width: 4),
          _TypeToggle(
            label: 'System',
            color: AppColors.system,
            active: provider.visibleTypes.contains('system'),
            onTap: () => provider.toggleTypeFilter('system'),
          ),
          const SizedBox(width: 12),
          // Search
          SizedBox(
            width: 180,
            child: TextField(
              onChanged: provider.setSearchQuery,
              style: const TextStyle(fontSize: 12, color: AppColors.textPrimary),
              decoration: InputDecoration(
                hintText: 'Search...',
                hintStyle:
                    const TextStyle(fontSize: 12, color: AppColors.textMuted),
                prefixIcon: const Icon(Icons.search,
                    size: 16, color: AppColors.textMuted),
                isDense: true,
                contentPadding: const EdgeInsets.symmetric(vertical: 8),
                filled: true,
                fillColor: AppColors.surfaceLight,
                border: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(6),
                  borderSide:
                      const BorderSide(color: AppColors.surfaceBorder),
                ),
                enabledBorder: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(6),
                  borderSide:
                      const BorderSide(color: AppColors.surfaceBorder),
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }

  String _formatTokens(int tokens) {
    if (tokens >= 1000000) return '${(tokens / 1000000).toStringAsFixed(1)}M';
    if (tokens >= 1000) return '${(tokens / 1000).toStringAsFixed(1)}K';
    return '$tokens';
  }
}

class _InfoChip extends StatelessWidget {
  final String label;
  const _InfoChip({required this.label});

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 3),
      decoration: BoxDecoration(
        color: AppColors.surfaceLight,
        borderRadius: BorderRadius.circular(4),
      ),
      child: Text(
        label,
        style: const TextStyle(fontSize: 11, color: AppColors.textMuted),
      ),
    );
  }
}

class _TypeToggle extends StatelessWidget {
  final String label;
  final Color color;
  final bool active;
  final VoidCallback onTap;

  const _TypeToggle({
    required this.label,
    required this.color,
    required this.active,
    required this.onTap,
  });

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: onTap,
      borderRadius: BorderRadius.circular(4),
      child: Container(
        padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
        decoration: BoxDecoration(
          color: active ? color.withAlpha(25) : Colors.transparent,
          borderRadius: BorderRadius.circular(4),
          border: Border.all(
            color: active ? color.withAlpha(80) : AppColors.surfaceBorder,
          ),
        ),
        child: Text(
          label,
          style: TextStyle(
            fontSize: 11,
            color: active ? color : AppColors.textMuted,
            fontWeight: active ? FontWeight.w600 : FontWeight.w400,
          ),
        ),
      ),
    );
  }
}