erDiagram
    %% ========================================
    %% CORE ENTITIES dengan RBAC
    %% ========================================
    ROLES ||--o{ USERS : "defines"
    USERS ||--o{ ITEMS : "reports_found"
    USERS ||--o{ LOST_ITEMS : "reports_lost"
    USERS ||--o{ CLAIMS : "submits"
    USERS ||--o{ CLAIMS : "verifies_as"
    USERS ||--o{ REVISION_LOGS : "creates"
    USERS ||--o{ NOTIFICATIONS : "receives"
    USERS ||--o{ AUDIT_LOGS : "performs"
    USERS ||--o{ ARCHIVES : "claims_item"
    
    %% ========================================
    %% CATEGORY & ATTACHMENT RELATIONS
    %% ========================================
    CATEGORIES ||--o{ ITEMS : "categorizes"
    CATEGORIES ||--o{ LOST_ITEMS : "categorizes"
    CATEGORIES ||--o{ ARCHIVES : "categorizes"
    ITEMS ||--o{ ATTACHMENTS : "has_photos"
    LOST_ITEMS ||--o{ ATTACHMENTS : "has_photos"
    
    %% ========================================
    %% CORE MATCHING & CLAIM LOGIC
    %% ========================================
    ITEMS ||--o{ CLAIMS : "receives"
    ITEMS ||--o{ REVISION_LOGS : "tracks_changes"
    ITEMS ||--|{ ARCHIVES : "becomes_archived"
    LOST_ITEMS ||--o{ MATCH_RESULTS : "matched_to"
    ITEMS ||--o{ MATCH_RESULTS : "matched_with"
    
    %% ========================================
    %% VERIFICATION PIPELINE (ETL)
    %% ========================================
    CLAIMS ||--|| CLAIM_VERIFICATIONS : "verified_by"
    CLAIM_VERIFICATIONS ||--o{ VERIFICATION_LOGS : "tracks_verification"
    
    %% ========================================
    %% TABLE DEFINITIONS WITH DETAILED SPECS
    %% ========================================
    
    ROLES {
        int id PK "AUTO_INCREMENT"
        string name UK "UNIQUE, NOT NULL"
        text description
        json permissions "RBAC permissions"
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE"
    }
    
    USERS {
        int id PK "AUTO_INCREMENT"
        string name "NOT NULL"
        string email UK "UNIQUE, INDEXED"
        string password "ENCRYPTED (bcrypt)"
        string nrp UK "UNIQUE, INDEXED"
        string phone
        int role_id FK "→ ROLES, INDEXED"
        string status "INDEXED, DEFAULT: active"
        datetime last_login
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE, INDEXED"
    }
    
    CATEGORIES {
        int id PK "AUTO_INCREMENT"
        string name "NOT NULL"
        string slug UK "UNIQUE, INDEXED"
        text description
        string icon_url
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE, INDEXED"
    }
    
    ITEMS {
        int id PK "AUTO_INCREMENT"
        string name "INDEXED, NOT NULL"
        int category_id FK "→ CATEGORIES, INDEXED"
        string location "INDEXED, NOT NULL"
        text description "SECRET (for verification)"
        text secret_details "Only for owner/admin"
        date date_found "INDEXED"
        string status "INDEXED, DEFAULT: unclaimed"
        int reporter_id FK "→ USERS, INDEXED"
        string reporter_name
        string reporter_contact
        int view_count "Default: 0"
        datetime expires_at "INDEXED, TRIGGER"
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "INDEXED"
    }
    
    LOST_ITEMS {
        int id PK "AUTO_INCREMENT"
        int user_id FK "→ USERS, CASCADE"
        string name "NOT NULL"
        int category_id FK "→ CATEGORIES, INDEXED"
        string color
        string location "INDEXED"
        text description "For auto-matching"
        date date_lost "INDEXED"
        string status "INDEXED, DEFAULT: active"
        datetime resolved_at
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE, INDEXED"
    }
    
    ATTACHMENTS {
        int id PK "AUTO_INCREMENT"
        int item_id FK "nullable, → ITEMS"
        int lost_item_id FK "nullable, → LOST_ITEMS"
        string file_url "NOT NULL"
        string file_type "jpg, png, etc"
        int file_size "in bytes"
        string upload_by_user_id FK "→ USERS"
        int display_order "for ordering"
        boolean is_primary "DEFAULT: FALSE"
        timestamp created_at
        timestamp updated_at
    }
    
    CLAIMS {
        int id PK "AUTO_INCREMENT"
        int item_id FK "→ ITEMS, CASCADE, INDEXED"
        int user_id FK "→ USERS, CASCADE, INDEXED"
        text description "User's verification desc"
        string proof_url
        string contact "NOT NULL"
        string status "INDEXED, DEFAULT: pending"
        text notes "Admin notes"
        datetime verified_at
        int verified_by FK "→ USERS, nullable"
        string rejection_reason
        int attempt_count "Default: 1"
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE, INDEXED"
    }
    
    CLAIM_VERIFICATIONS {
        int id PK "AUTO_INCREMENT"
        int claim_id FK "UNIQUE, → CLAIMS"
        decimal similarity_score "0-100, INDEXED"
        text matched_keywords "JSON format"
        text verification_notes
        boolean is_auto_matched "DEFAULT: FALSE"
        string verification_method "manual/auto"
        json metadata "Additional verification data"
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE"
    }
    
    VERIFICATION_LOGS {
        int id PK "AUTO_INCREMENT"
        int verification_id FK "→ CLAIM_VERIFICATIONS"
        int verified_by_user_id FK "→ USERS"
        string action "approve/reject/pending"
        text reason
        timestamp created_at
    }
    
    MATCH_RESULTS {
        int id PK "AUTO_INCREMENT"
        int lost_item_id FK "→ LOST_ITEMS, INDEXED"
        int item_id FK "→ ITEMS, INDEXED"
        decimal similarity_score "0-100, threshold: 70"
        text matched_fields "JSON format"
        string match_reason "color/location/description"
        datetime matched_at
        boolean is_notified "INDEXED, DEFAULT: FALSE"
        datetime notified_at
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE, INDEXED"
    }
    
    ARCHIVES {
        int id PK "AUTO_INCREMENT"
        int item_id FK "UNIQUE, Original ID"
        string name
        int category_id FK "→ CATEGORIES, INDEXED"
        string photo_url
        string location
        text description
        date date_found
        string status
        string reporter_name
        string reporter_contact
        string archived_reason "expired/closed/claimed"
        int claimed_by FK "→ USERS, SET NULL"
        datetime archived_at "INDEXED"
        timestamp created_at
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE, INDEXED"
    }
    
    REVISION_LOGS {
        int id PK "AUTO_INCREMENT"
        int item_id FK "→ ITEMS, CASCADE, INDEXED"
        int user_id FK "→ USERS, CASCADE, INDEXED"
        string field_name "changed field"
        text old_value
        text new_value
        text reason
        timestamp created_at "INDEXED"
        timestamp deleted_at "SOFT DELETE"
    }
    
    AUDIT_LOGS {
        int id PK "AUTO_INCREMENT"
        int user_id FK "nullable, → USERS, INDEXED"
        string action "INDEXED (CREATE/READ/UPDATE/DELETE)"
        string entity_type "INDEXED (table name)"
        int entity_id "INDEXED"
        json details "Change details"
        string ip_address
        string user_agent
        timestamp created_at "INDEXED"
        timestamp deleted_at "SOFT DELETE"
    }
    
    NOTIFICATIONS {
        int id PK "AUTO_INCREMENT"
        int user_id FK "→ USERS, CASCADE, INDEXED"
        string type "INDEXED (match/claim/update)"
        string title
        text message
        string entity_type "INDEXED"
        int entity_id
        string channel "email/sms/push"
        boolean is_read "INDEXED, DEFAULT: FALSE"
        datetime read_at
        timestamp created_at "INDEXED"
        timestamp updated_at
        timestamp deleted_at "SOFT DELETE"
    }