ash469/pims-leave-app

Purpose and Runtime

PIMS is a Flutter client for institutional leave management across student, parent, warden, and guard roles. It targets Android, iOS, web, Linux, macOS, and Windows; the operational product is primarily a mobile workflow. Flutter starts from lib/main.dart, with platform host bootstraps such as android/app/src/main/kotlin/com/pims/pims_app/MainActivity.kt and ios/Runner/AppDelegate.swift.

Application Composition and Navigation

The UI is organized as role-specific screens rather than feature modules. Initial role choice and Google login determine the active dashboard, then each role reaches its permitted workflow.

• Entry/access: lib/main.dart, lib/screens/role_selection_screen.dart, lib/screens/login_screen.dart

• Dashboards: lib/screens/student_dashboard_screen.dart, lib/screens/parent_dashboard_screen.dart, lib/screens/warden_dashboard_screen.dart

• Guard operations: lib/screens/guard_dashboard_screen.dart, lib/screens/raise_concern_screen.dart, lib/screens/qr_scanner_screen.dart

Identity and Authorization Boundary

Authentication is Firebase Authentication with Google Sign-In; application role authorization is implied by the login and backend/service layer rather than by separate client applications. Firebase initialization/configuration is held in lib/firebase_options.dart; authentication calls are centralized in lib/services/auth_service.dart. Native Firebase credentials exist for iOS at ios/Runner/GoogleService-Info.plist; Android requires its equivalent deployment configuration.

Leave Lifecycle

The core domain flow is: student creates a leave request, parent performs first approval, warden performs final approval, and approved leave information becomes available for gate validation. Shared domain entities are defined in lib/models/data_models.dart; mutations and retrieval flow through lib/services/leave_service.dart. Role-specific processing is exposed through lib/services/parent_service.dart and lib/services/warden_service.dart, with UI stages in lib/screens/leave_request_screen.dart and lib/screens/leave_details_screen.dart.

Gate Verification and Concerns

Approved leaves generate QR-based credentials. Guards scan them to mark departure/return, placing the scanner at a trust boundary between a presented code and server-side leave status. Scanner UI/rendering is in lib/screens/qr_scanner_screen.dart, lib/widgets/qr_scan_body.dart, and lib/helpers/qr_handler.dart. Guard-raised issues, optionally with attachments, are handled through lib/screens/raise_concern_screen.dart and lib/services/concern_service.dart.

Notifications and Local Behavior

Leave-state changes are surfaced through in-app notifications and Firebase Cloud Messaging. FCM integration is centralized in lib/services/fcm_service.dart; notification data/UI is handled by lib/services/notification_service.dart and lib/screens/notifications_screen.dart. The README states offline persistence, though the concrete storage implementation is not identifiable from the provided tree.

External Systems and Delivery

The Flutter client calls a Node.js API hosted on Render, which persists operational data in MongoDB; neither backend code nor database schema is present here. Firebase provides Authentication and FCM. Firebase hosting/project metadata is represented by firebase.json. CI/build delivery is configured through .gitlab-ci.yml and codemagic.yaml; native packaging resides under android/, ios/, and the other Flutter platform directories.