feat: implement core backend API structure and frontend service layer for case management and authentication

backend/routes/auth.py

@@ -0,0 +1,88 @@
+# backend/routes/auth.py
+from flask import Blueprint, request, jsonify
+from datetime import datetime, timedelta
+import bcrypt
+import jwt
+
+from ..db import get_db_connection, release_db_connection
+from ..middleware import SECRET_KEY, token_required
+
+auth_blueprint = Blueprint('auth', __name__)
+
+@auth_blueprint.route('/auth/register', methods=['POST'])
+def register():
+    data = request.json
+    username = data.get('username')
+    password = data.get('password')
+    
+    if not username or not password:
+        return jsonify({"error": "Username and password are required"}), 400
+        
+    conn = get_db_connection()
+    cur = conn.cursor()
+    
+    # Check if exists
+    cur.execute("SELECT id FROM users WHERE username = %s", (username,))
+    if cur.fetchone():
+        release_db_connection(conn)
+        return jsonify({"error": "Username already exists"}), 400
+        
+    hashed_password = bcrypt.hashpw(password.encode('utf-8'), bcrypt.gensalt()).decode('utf-8')
+    
+    cur.execute(
+        "INSERT INTO users (username, password_hash) VALUES (%s, %s) RETURNING id",
+        (username, hashed_password)
+    )
+    user_id = cur.fetchone()[0]
+    conn.commit()
+    release_db_connection(conn)
+    
+    return jsonify({"message": "User registered successfully", "user_id": user_id}), 201
+
+@auth_blueprint.route('/auth/login', methods=['POST'])
+def login():
+    data = request.json
+    username = data.get('username')
+    password = data.get('password')
+    
+    conn = get_db_connection()
+    cur = conn.cursor()
+    cur.execute("SELECT id, password_hash FROM users WHERE username = %s", (username,))
+    user = cur.fetchone()
+    release_db_connection(conn)
+    
+    if not user or not bcrypt.checkpw(password.encode('utf-8'), user[1].encode('utf-8')):
+        return jsonify({"error": "Invalid credentials"}), 401
+        
+    token = jwt.encode({
+        'user_id': user[0],
+        'exp': datetime.utcnow() + timedelta(days=7)
+    }, SECRET_KEY, algorithm="HS256")
+    
+    return jsonify({"token": token})
+
+@auth_blueprint.route('/auth/me', methods=['GET'])
+@token_required
+def get_me(current_user_id):
+    conn = get_db_connection()
+    cur = conn.cursor()
+    cur.execute("SELECT id, username, plan FROM users WHERE id = %s", (current_user_id,))
+    user = cur.fetchone()
+    release_db_connection(conn)
+    
+    if not user:
+        return jsonify({"error": "User not found"}), 404
+        
+    return jsonify({"id": user[0], "username": user[1], "plan": user[2]})
+
+@auth_blueprint.route('/auth/upgrade', methods=['POST'])
+@token_required
+def upgrade_plan(current_user_id):
+    """Simulates payment success and upgrades to PRO."""
+    conn = get_db_connection()
+    cur = conn.cursor()
+    cur.execute("UPDATE users SET plan = 'pro' WHERE id = %s", (current_user_id,))
+    conn.commit()
+    release_db_connection(conn)
+    
+    return jsonify({"message": "Successfully upgraded to PRO"}), 200