feat: adds deployment records for seismographs.

backend/migrate_add_deployment_records.py

@@ -0,0 +1,79 @@
+"""
+Migration: Add deployment_records table.
+
+Tracks each time a unit is sent to the field and returned.
+The active deployment is the row with actual_removal_date IS NULL.
+
+Run once per database:
+    python backend/migrate_add_deployment_records.py
+"""
+
+import sqlite3
+import os
+
+DB_PATH = "./data/seismo_fleet.db"
+
+
+def migrate_database():
+    if not os.path.exists(DB_PATH):
+        print(f"Database not found at {DB_PATH}")
+        return
+
+    conn = sqlite3.connect(DB_PATH)
+    cursor = conn.cursor()
+
+    try:
+        # Check if table already exists
+        cursor.execute("""
+            SELECT name FROM sqlite_master
+            WHERE type='table' AND name='deployment_records'
+        """)
+        if cursor.fetchone():
+            print("✓ deployment_records table already exists, skipping")
+            return
+
+        print("Creating deployment_records table...")
+        cursor.execute("""
+            CREATE TABLE deployment_records (
+                id TEXT PRIMARY KEY,
+                unit_id TEXT NOT NULL,
+                deployed_date DATE,
+                estimated_removal_date DATE,
+                actual_removal_date DATE,
+                project_ref TEXT,
+                project_id TEXT,
+                location_name TEXT,
+                notes TEXT,
+                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+            )
+        """)
+
+        cursor.execute("""
+            CREATE INDEX idx_deployment_records_unit_id
+            ON deployment_records(unit_id)
+        """)
+        cursor.execute("""
+            CREATE INDEX idx_deployment_records_project_id
+            ON deployment_records(project_id)
+        """)
+        # Index for finding active deployments quickly
+        cursor.execute("""
+            CREATE INDEX idx_deployment_records_active
+            ON deployment_records(unit_id, actual_removal_date)
+        """)
+
+        conn.commit()
+        print("✓ deployment_records table created successfully")
+        print("✓ Indexes created")
+
+    except Exception as e:
+        conn.rollback()
+        print(f"✗ Migration failed: {e}")
+        raise
+    finally:
+        conn.close()
+
+
+if __name__ == "__main__":
+    migrate_database()