import 'package:flutter/material.dart';
import 'package:permission_handler/permission_handler.dart';
import 'package:saf/saf.dart';
import 'package:sheetless/sheetview.dart';

import 'sheet.dart';

void main() {
  runApp(const MyApp());
}

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Sheetless',
      theme: ThemeData(
        useMaterial3: true,
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key});

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

class _MyHomePageState extends State<MyHomePage> {
  @override
  void initState() {
    super.initState();
  }

  Future<String?> getSafPickedSheetsDirectory() async {
    await Permission.storage.request();
    await Permission.manageExternalStorage.request();
    var pickedDirectories = await Saf.getPersistedPermissionDirectories();
    if (pickedDirectories == null || pickedDirectories.isEmpty) {
      return null;
    }
    return pickedDirectories.last;
  }

  Future<List<Sheet>> acquireSheets() async {
    String? sheetsDirectory = await getSafPickedSheetsDirectory();
    if (sheetsDirectory == null || sheetsDirectory.isEmpty) {
      await Saf.getDynamicDirectoryPermission(grantWritePermission: false);
      sheetsDirectory = await getSafPickedSheetsDirectory();
      if (sheetsDirectory == null || sheetsDirectory.isEmpty) {
        throw Exception("No Directory selected");
      }
    }

    var sheetsDirectoryFiles = await Saf.getFilesPathFor(sheetsDirectory);
    if (sheetsDirectoryFiles == null) {
      await Saf.releasePersistedPermissions();
      throw Exception(
          "Permissions for directory no longer valid or Directory deleted. Please restart app.");
    }
    return loadSheetsSorted(sheetsDirectoryFiles);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("My Sheets"),
      ),
      body: FutureBuilder(
          future: acquireSheets(),
          builder: (BuildContext context, AsyncSnapshot<List<Sheet>> snapshot) {
            if (snapshot.hasData) {
              return SheetsWidget(
                sheets: snapshot.data!,
                callback: (sheet) => Navigator.push(
                  context,
                  MaterialPageRoute(
                    builder: (context) => SheetViewerPage(sheet: sheet),
                  ),
                ),
              );
            } else if (snapshot.hasError) {
              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());
            }
          }),
    );
  }
}