📦 Lost & Found: Campus Asset Recovery System

A decentralized, trust-based platform for efficient campus asset recovery.
Built using Flutter & Supabase.

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📖 Overview

Traditional campus lost-and-found systems often rely on inefficient methods such as physical notice boards or unstructured chat groups. These systems suffer from low visibility, privacy risks regarding personal contact information, and a lack of verification mechanisms.

Lost & Found digitizes this process into a structured, peer-to-peer ecosystem. The platform leverages geospatial tagging for precise item location and introduces a Two-Handshake Protocol to verify physical handovers, ensuring security and trust within the campus community.

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🚀 Key Features

🗺️ Geospatial Tagging & Visualization

• Precision Pinning: Finders can mark the exact coordinates of a found item on an interactive map.
• Geospatial Browsing: Users can visually explore the map to locate items found near specific campus landmarks (e.g., Lab 301, Main Cafeteria).

🤝 Two-Handshake Verification Protocol

To prevent fraudulent claims and ensure item recovery, the system enforces a strict double-confirmation logic:

1. Finder Action: Marks the item as Handed Over (Status updates to verification_pending).
2. Owner Action: Receives a prompt to Confirm Receipt upon physical retrieval.
3. Completion: The transaction closes only when both parties confirm, triggering the reputation algorithm.

🌟 Reputation & Incentive System

• Trust Scoring: Successful returns award the finder +1 Reputation Point via secure database functions.
• Civic Gamification: A leaderboard system incentivizes active participation and honest behavior.
• Security: Reputation logic is handled via secure PostgreSQL RPCs to prevent client-side manipulation.

🛡️ Privacy-Centric Architecture

• Data Protection: User contact details (Email/Phone) are masked by default.
• Conditional Disclosure:
  • Finders view Owner details only after a claim is initiated.
  • Owners view Finder details only after a claim is preliminarily approved.

👮 Administration & Moderation

• Content Management: Automated and manual tools to flag spam or inappropriate content.
• Data Integrity: Database constraints ensure consistency during post deletion or user removal.

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📸 User Journey

1. Reporting: A user locates a lost item, captures an image, and pins the location on the map.
2. Claiming: The owner identifies the item via the feed or map and submits a claim with specific proof.
3. Verification: The finder reviews the proof and approves the claim. Contact information is mutually revealed.
4. Handover: Both parties meet. The finder initiates the handover sequence in the app.
5. Confirmation: The owner confirms receipt, closing the ticket and updating the finder's reputation score.

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🛠️ Technical Architecture

• Frontend: Flutter (Dart)
• Backend: Supabase (PostgreSQL)
• Authentication: Google OAuth & Secure Email/Password
• Mapping: flutter_map / Google Maps API
• State Management: setState / Provider
• Database Logic: PL/pgSQL functions for secure transaction handling

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⚡ Quick Start Guide

1. Prerequisites

Ensure the Flutter SDK is installed and configured:

flutter --version

2. Installation

Clone the repository and install dependencies:

git clone <repository-url>
cd lost_and_found_app
flutter pub get

3. Environment Configuration

Create a .env file in the root directory containing your Supabase credentials:

SUPABASE_URL=https://your-project-id.supabase.co
SUPABASE_ANON_KEY=your-long-anon-key-here

4. Database Initialization

Execute the following SQL function in the Supabase SQL Editor to enable the reputation system:

create or replace function increment_reputation(user_id uuid, amount int)
returns void as $$
begin
  update profiles
  set reputation = coalesce(reputation, 0) + amount
  where id = user_id;
end;
$$ language plpgsql security definer;

5. Execution

Run the application on a connected device or emulator:

flutter run

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📄 License

This project is licensed under the MIT License.