import 'dart:io';
import 'dart:typed_data';

import 'package:alert_dialog/alert_dialog.dart';
import 'package:flutter/material.dart';
import 'package:flutter_hooks/flutter_hooks.dart';
import 'package:flutter_pdfview/flutter_pdfview.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:logging/logging.dart';
import 'package:moneymgr_mobile/services/storage/expenses.dart';
import 'package:moneymgr_mobile/services/storage/prefs.dart';
import 'package:moneymgr_mobile/utils/time_utils.dart';
import 'package:riverpod_annotation/riverpod_annotation.dart';
import 'package:scanbot_sdk/scanbot_sdk.dart';
import 'package:scanbot_sdk/scanbot_sdk_ui_v2.dart' hide IconButton, EdgeInsets;

part 'scan_screen.g.dart';

@riverpod
Future<Uint8List?> _scanDocument(Ref ref) async {
  var configuration = DocumentScanningFlow(
    appearance: DocumentFlowAppearanceConfiguration(
      statusBarMode: StatusBarMode.DARK,
    ),
    cleanScanningSession: true,
    outputSettings: DocumentScannerOutputSettings(pagesScanLimit: 1),
    screens: DocumentScannerScreens(
      review: ReviewScreenConfiguration(enabled: false),
    ),
  );
  var documentResult = await ScanbotSdkUiV2.startDocumentScanner(configuration);

  if (documentResult.status != OperationStatus.OK) {
    throw Exception("Scanner failed with status ${documentResult.status}");
  }

  // Convert result to PDF
  var result = await ScanbotSdk.document.createPDFForDocument(
    PDFFromDocumentParams(
      documentID: documentResult.data!.uuid,
      pdfConfiguration: PdfConfiguration(),
    ),
  );
  final pdfPath = result.pdfFileUri.replaceFirst("file://", "");
  return File(pdfPath).readAsBytes();
}

class ScanScreen extends HookConsumerWidget {
  const ScanScreen({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final boredSuggestion = ref.watch(_scanDocumentProvider);

    restartScan() async {
      try {
        final val = ref.refresh(_scanDocumentProvider);
        Logger.root.info("Load again startup result: $val");
      } catch (e, s) {
        Logger.root.shout("Failed to try again startup loading! $e $s");
      }
    }

    // Perform a switch-case on the result to handle loading/error states
    return Padding(
      padding: const EdgeInsets.all(8.0),
      child: switch (boredSuggestion) {
        AsyncData(:final value) when value != null => ExpenseEditor(
          file: value,
          onFinished: (e) {},
        ),

        // No data
        AsyncData(:final value) when value == null => ScanErrorScreen(
          message: "No document scanned!",
          onTryAgain: restartScan,
        ),

        // Error
        AsyncError(:final error) => ScanErrorScreen(
          message: error.toString(),
          onTryAgain: restartScan,
        ),
        _ => const Center(child: CircularProgressIndicator()),
      },
    );
  }
}

class ScanErrorScreen extends StatelessWidget {
  final String message;
  final Function() onTryAgain;

  const ScanErrorScreen({
    super.key,
    required this.message,
    required this.onTryAgain,
  });

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          Spacer(flex: 5),
          Text("An error occurred while scanning"),
          Spacer(flex: 1),
          Text(message),
          Spacer(flex: 1),
          MaterialButton(
            onPressed: onTryAgain,
            child: Text("Try again".toUpperCase()),
          ),
          Spacer(flex: 5),
        ],
      ),
    );
  }
}

class ExpenseEditor extends HookConsumerWidget {
  final Uint8List file;
  final Function(Expense) onFinished;

  const ExpenseEditor({
    super.key,
    required this.file,
    required this.onFinished,
  });

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final serverConfig = ref.watch(prefsProvider).requireValue.serverConfig()!;

    final labelController = useTextEditingController();
    final costController = useTextEditingController();
    final timeController = useState(DateTime.now());

    // Pick a new date
    handlePickDate() async {
      final date = await showDatePicker(
        context: context,
        firstDate: DateTime(2000),
        lastDate: DateTime(2099),
        initialDate: timeController.value,
      );
      if (date != null) timeController.value = date;
    }

    return ListView(
      children: [
        // Expense preview
        SizedBox(
          height: 200,
          child: PDFView(
            pdfData: file,
            onError: (e) {
              Logger.root.warning("Failed to render PDF $e");
              alert(context, content: Text("Failed to render PDF $e"));
            },
            fitPolicy: FitPolicy.BOTH,
          ),
        ),

        SizedBox(height: 10),

        // Cost
        TextField(
          controller: costController,
          keyboardType: TextInputType.number,
          decoration: const InputDecoration(labelText: 'Cost'),
          textInputAction: TextInputAction.done,
        ),

        SizedBox(height: 10),

        // Label
        TextField(
          controller: labelController,
          keyboardType: TextInputType.text,
          decoration: const InputDecoration(labelText: 'Label'),
          textInputAction: TextInputAction.done,
          maxLength: serverConfig.constraints.inbox_entry_label.max,
        ),

        SizedBox(height: 10),

        // Date
        TextField(
          enabled: true,
          readOnly: true,
          controller: TextEditingController(
            text: timeController.value.simpleDate,
          ),
          keyboardType: TextInputType.datetime,
          decoration: InputDecoration(
            labelText: 'Date',
            suffixIcon: IconButton(
              onPressed: handlePickDate,
              icon: const Icon(Icons.date_range),
            ),
          ),
        ),
      ],
    );
  }
}