import "package:shadcn_flutter/shadcn_flutter.dart";

import "../../../../src/project_store.dart";
import "../../../../src/session/session_types.dart";
import "../../../providers/projects_provider.dart";
import "../../../providers/session_provider.dart";

class ThreadsSection extends StatelessWidget {
  const ThreadsSection({
    required this.projectsProvider,
    required this.sessionProvider,
    required this.sessionsByProject,
    required this.onOpenSession,
    required this.onSelectProject,
    required this.onDeleteSession,
  });

  final ProjectsProvider projectsProvider;
  final SessionProvider sessionProvider;
  final Map<String, List<SessionSummary>> sessionsByProject;
  final ValueChanged<SessionSummary> onOpenSession;
  final ValueChanged<ProjectRecord> onSelectProject;
  final ValueChanged<SessionSummary> onDeleteSession;

  @override
  Widget build(BuildContext context) {
    // Sort sessions by update time (newest first) within each project
    final sortedSessionsByProject = <String, List<SessionSummary>>{};
    sessionsByProject.forEach((workingDirectory, sessions) {
      final sortedSessions = List<SessionSummary>.from(sessions)
        ..sort((a, b) => b.updated.compareTo(a.updated));
      sortedSessionsByProject[workingDirectory] = sortedSessions;
    });

    return ListView(
      padding: const EdgeInsets.fromLTRB(8, 0, 8, 12),
      children: [
        if (projectsProvider.projects.isEmpty)
          const _SidebarHint(text: "No projects yet")
        else
          for (final project in projectsProvider.projects) ...[
            // Project header
            SizedBox(
              width: double.infinity,
              child: Button.ghost(
                onPressed: () => onSelectProject(project),
                child: Container(
                  padding: const EdgeInsets.symmetric(vertical: 6),
                  child: Text(
                    project.name,
                    style: TextStyle(
                      fontWeight: FontWeight.w600,
                      fontSize: 12,
                      color: Theme.of(context).colorScheme.mutedForeground,
                    ),
                  ),
                ),
              ),
            ),
            // Project sessions
            if (sortedSessionsByProject[project.workingDirectory]?.isEmpty ??
                true)
              const Padding(
                padding: EdgeInsets.fromLTRB(8, 4, 8, 8),
                child: _SidebarHint(text: "No threads yet"),
              )
            else
              for (final session
                  in sortedSessionsByProject[project.workingDirectory]!)
                _SidebarSessionTile(
                  session: session,
                  isSelected: sessionProvider.currentSessionId == session.id,
                  onTap: () => onOpenSession(session),
                  onDelete: () => onDeleteSession(session),
                ),
            const Divider(height: 16),
          ],
        // Handle sessions that don't belong to any current project
        if (sortedSessionsByProject.keys.any(
          (key) => !projectsProvider.projects.any(
            (project) => project.workingDirectory == key,
          ),
        )) ...[
          Padding(
            padding: const EdgeInsets.fromLTRB(8, 8, 8, 4),
            child: Text(
              "Sessions Without Projects",
              style: TextStyle(
                fontWeight: FontWeight.w600,
                fontSize: 12,
                color: Theme.of(context).colorScheme.mutedForeground,
              ),
            ),
          ),
          for (final entry in sortedSessionsByProject.entries)
            if (!projectsProvider.projects.any(
                  (project) => project.workingDirectory == entry.key,
                ) &&
                entry.key.isNotEmpty)
              for (final session in entry.value)
                _SidebarSessionTile(
                  session: session,
                  isSelected: sessionProvider.currentSessionId == session.id,
                  onTap: () => onOpenSession(session),
                  onDelete: () => onDeleteSession(session),
                ),
        ],
      ],
    );
  }
}

class _SidebarHint extends StatelessWidget {
  const _SidebarHint({required this.text});

  final String text;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 6),
      child: Text(text).textSmall.muted,
    );
  }
}

class _SidebarSessionTile extends StatelessWidget {
  const _SidebarSessionTile({
    required this.session,
    required this.isSelected,
    required this.onTap,
    required this.onDelete,
  });

  final SessionSummary session;
  final bool isSelected;
  final VoidCallback onTap;
  final VoidCallback onDelete;

  @override
  Widget build(BuildContext context) {
    return ContextMenu(
      items: [
        MenuButton(
          onPressed: (context) {
            onDelete();
          },
          child: const Text("Delete"),
        ),
      ],
      child: SizedBox(
        width: double.infinity,
        child: Button(
          style: isSelected ? ButtonStyle.secondary() : ButtonStyle.ghost(),
          child: Text(
            session.name,
            maxLines: 1,
            overflow: TextOverflow.ellipsis,
            style: TextStyle(fontWeight: FontWeight.w400, fontSize: 13),
          ).textSmall,
          trailing: Text(
            _formatRelativeTime(session.updated),
            style: TextStyle(fontWeight: FontWeight.w400, fontSize: 13),
          ).muted.textSmall,
          onPressed: () {
            onTap();
          },
        ),
      ),
    );
  }
}

String _formatRelativeTime(DateTime timestamp) {
  final difference = DateTime.now().toUtc().difference(timestamp.toUtc());

  if (difference.inMinutes < 1) {
    return "just now";
  }
  if (difference.inHours < 1) {
    return "${difference.inMinutes}m";
  }
  if (difference.inDays < 1) {
    return "${difference.inHours}h";
  }
  if (difference.inDays < 7) {
    return "${difference.inDays}d";
  }

  final month = timestamp.month.toString().padLeft(2, "0");
  final day = timestamp.day.toString().padLeft(2, "0");
  return "${timestamp.year}-$month-$day";
}