import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_fullscreen/flutter_fullscreen.dart';
import 'package:logging/logging.dart';
import 'package:sheetless/login_page.dart';
import 'package:sheetless/sheet_viewer_page.dart';
import 'package:sheetless/storage_helper.dart';
import 'package:package_info_plus/package_info_plus.dart';

import 'api.dart';
import 'sheet.dart';

class MyHomePage extends StatefulWidget {
  final Config config;

  const MyHomePage({super.key, required this.config});

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> with FullScreenListener {
  ApiClient? apiClient;
  Future<bool> apiLoggedIn = Future.value(false);
  final StorageHelper _storageHelper = StorageHelper();
  final log = Logger("MyHomePage");
  String? appName;
  String? appVersion;
  bool shuffling = false;
  late Future<List<Sheet>> sheets;

  @override
  void initState() {
    FullScreen.addListener(this);

    // Load saved fullscreen
    FullScreen.setFullScreen(widget.config.fullscreen);

    super.initState();
    _loadAppInfo();
    sheets = acquireSheets();
  }

  @override
  void dispose() {
    FullScreen.removeListener(this);
    super.dispose();
  }

  Future<void> _loadAppInfo() async {
    final info = await PackageInfo.fromPlatform();
    setState(() {
      appName = info.appName;
      appVersion = info.version;
    });
  }

  Future<List<Sheet>> acquireSheets() async {
    final url = await _storageHelper.readSecure(SecureStorageKey.url);
    final jwt = await _storageHelper.readSecure(SecureStorageKey.jwt);
    apiClient = ApiClient(baseUrl: url!, token: jwt);
    // TODO: check if really logged in
    final sheets = await apiClient!.fetchSheets();
    log.info("${sheets.length} sheets fetched");
    final sheetsSorted = await sortSheetsByRecency(sheets);
    log.info("${sheetsSorted.length} sheets sorted");

    // TODO: make work
    // final changeQueue = await _storageHelper.readChangeQueue();
    // changeQueue.applyToSheets(sheetsSorted);
    // log.info("${changeQueue.length()} changes applied");

    return sheetsSorted;
  }

  Future<List<Sheet>> sortSheetsByRecency(List<Sheet> sheets) async {
    final accessTimes = await _storageHelper.readSheetAccessTimes();

    sheets.sort((a, b) {
      var dateA = accessTimes[a.uuid];
      var dateB = accessTimes[b.uuid];

      if (dateA == null || a.updatedAt.isAfter(dateA)) {
        dateA = a.updatedAt;
      }
      if (dateB == null || b.updatedAt.isAfter(dateB)) {
        dateB = b.updatedAt;
      }

      return dateB.compareTo(dateA);
    });

    return sheets;
  }

  Future<void> _logOut() async {
    // Delete saved jwt
    await _storageHelper.writeSecure(SecureStorageKey.jwt, null);

    if (!mounted) return; // Widget already removed

    Navigator.of(
      context,
    ).pushReplacement(MaterialPageRoute(builder: (_) => LoginPage()));
  }

  void switchShufflingState(bool newState) async {
    if (newState) {
      (await sheets).shuffle();
    } else {
      sheets = sortSheetsByRecency(await sheets);
    }

    setState(() {
      shuffling = newState;
    });
  }

  Drawer _buildDrawer() {
    return Drawer(
      child: SafeArea(
        child: Padding(
          padding: EdgeInsetsGeometry.directional(start: 10, end: 10, top: 30),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              // Drawer Actions
              Column(
                children: [
                  ListTile(
                    leading: Icon(
                      Icons.shuffle,
                      color: shuffling ? Colors.blue : null,
                    ),
                    title: const Text('Shuffle'),
                    onTap: () {
                      switchShufflingState(!shuffling);
                    },
                  ),
                  ListTile(
                    leading: Icon(
                      widget.config.fullscreen
                          ? Icons.fullscreen_exit
                          : Icons.fullscreen,
                    ),
                    title: widget.config.fullscreen
                        ? const Text('Exit Fullscreen')
                        : const Text('Enter Fullscreen'),
                    onTap: toggleFullscreen,
                  ),
                  ListTile(
                    leading: const Icon(Icons.logout),
                    title: const Text('Logout'),
                    onTap: _logOut,
                  ),
                ],
              ),

              // App Info at bottom
              Padding(
                padding: const EdgeInsets.all(16.0),
                child: Text(
                  '$appName v$appVersion',
                  style: const TextStyle(color: Colors.grey),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  @override
  void onFullScreenChanged(bool enabled, SystemUiMode? systemUiMode) {
    setState(() {
      widget.config.fullscreen = enabled;
      _storageHelper.writeConfig(widget.config);
    });
  }

  void toggleFullscreen() {
    FullScreen.setFullScreen(!widget.config.fullscreen);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      // Icon for drawer appears automatically
      appBar: AppBar(title: const Text("Sheetless")),
      endDrawer: _buildDrawer(),
      body: FutureBuilder(
        future: sheets,
        builder: (BuildContext context, AsyncSnapshot<List<Sheet>> snapshot) {
          if (snapshot.hasData) {
            return SheetsWidget(
              sheets: snapshot.data!,
              onSheetOpenRequest: (sheet) {
                _storageHelper.writeSheetAccessTime(sheet.uuid, DateTime.now());
                Navigator.push(
                  context,
                  MaterialPageRoute(
                    builder: (context) => SheetViewerPage(
                      sheet: sheet,
                      apiClient: apiClient!,
                      config: widget.config,
                    ),
                  ),
                );
              },
            );
          } else if (snapshot.hasError) {
            log.warning("Error loading sheets:", snapshot.error);
            return Center(
              child: Text(
                style: Theme.of(
                  context,
                ).textTheme.displaySmall!.copyWith(color: Colors.red),
                textAlign: TextAlign.center,
                snapshot.error.toString(),
              ),
            );
          } else {
            return const Center(child: CircularProgressIndicator());
          }
        },
      ),
    );
  }
}