import 'dart:io';

import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:image_picker/image_picker.dart';
import 'package:path/path.dart' as p;
import 'package:path_provider/path_provider.dart';

import '../../../core/constants/app_defaults.dart';
import '../../../core/providers/app_providers.dart';
import '../../../data/local/models/models.dart';

final profileProvider =
    AsyncNotifierProvider<ProfileNotifier, UserProfile>(ProfileNotifier.new);

class ProfileNotifier extends AsyncNotifier<UserProfile> {
  @override
  Future<UserProfile> build() async {
    final isar = await ref.watch(isarProvider.future);
    final profile = await isar.userProfiles.get(AppDefaults.singletonId);
    if (profile == null) {
      // Bootstrap should have created one; create defensively.
      final fresh = UserProfile.createDefault();
      await isar.writeTxn(() => isar.userProfiles.put(fresh));
      return fresh;
    }
    if (_isLocalAvatarMissing(profile)) {
      return _clearMissingLocalAvatar(profile);
    }
    return profile;
  }

  bool _isLocalAvatarMissing(UserProfile profile) {
    if (profile.avatarSource != AvatarSource.localFile) return false;
    final path = profile.avatarLocalPath?.trim();
    if (path == null || path.isEmpty) return true;
    return !File(path).existsSync();
  }

  Future<UserProfile> _clearMissingLocalAvatar(UserProfile current) async {
    final updated = current.copyWith(
      avatarAssetPath: AppDefaults.defaultAvatarAssetPath,
      avatarLocalPath: null,
      avatarSource: AvatarSource.asset,
    );
    final isar = await ref.read(isarProvider.future);
    await isar.writeTxn(() => isar.userProfiles.put(updated));
    return updated;
  }

  Future<void> updateNickname(String nickname) async {
    final trimmed = nickname.trim();
    if (trimmed.isEmpty) return;
    final current = state.value;
    if (current == null) return;
    final updated = current.copyWith(nickname: trimmed);
    final isar = await ref.read(isarProvider.future);
    await isar.writeTxn(() => isar.userProfiles.put(updated));
    state = AsyncData(updated);
  }

  /// Picks an image from gallery or camera, copies it into the app sandbox
  /// and stores the local file path on the profile.
  Future<bool> updateAvatar({required bool fromCamera}) async {
    final current = state.value;
    if (current == null) return false;

    final picker = ImagePicker();
    final xfile = await picker.pickImage(
      source: fromCamera ? ImageSource.camera : ImageSource.gallery,
      maxWidth: 512,
      maxHeight: 512,
      imageQuality: 85,
    );
    if (xfile == null) return false;

    final docs = await getApplicationDocumentsDirectory();
    final destPath = p.join(docs.path, AppDefaults.avatarFileName);
    final sourceFile = File(xfile.path);
    await sourceFile.copy(destPath);

    final updated = current.copyWith(
      avatarLocalPath: destPath,
      avatarSource: AvatarSource.localFile,
    );
    final isar = await ref.read(isarProvider.future);
    await isar.writeTxn(() => isar.userProfiles.put(updated));
    state = AsyncData(updated);
    return true;
  }

  Future<void> resetAvatar() async {
    final current = state.value;
    if (current == null) return;

    final path = current.avatarLocalPath;
    if (path != null && path.isNotEmpty) {
      final file = File(path);
      if (await file.exists()) {
        try {
          await file.delete();
        } catch (_) {
          // Best-effort cleanup; profile reset still proceeds.
        }
      }
    }

    final updated = current.copyWith(
      avatarAssetPath: AppDefaults.defaultAvatarAssetPath,
      avatarLocalPath: null,
      avatarSource: AvatarSource.asset,
    );
    final isar = await ref.read(isarProvider.future);
    await isar.writeTxn(() => isar.userProfiles.put(updated));
    state = AsyncData(updated);
  }
}