Initial commit: Backend API Phase 1a complete

- FastAPI backend with JWT auth
- PostgreSQL database schema
- Trees and Sessions CRUD APIs
- Export functionality (Markdown, Text, HTML)
- Docker setup for local development
- Alembic migrations

backend/app/api/endpoints/auth.py

@@ -0,0 +1,159 @@
+from datetime import datetime, timezone
+from typing import Annotated
+from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi.security import OAuth2PasswordRequestForm
+from sqlalchemy.ext.asyncio import AsyncSession
+from sqlalchemy import select
+
+from app.core.database import get_db
+from app.core.security import (
+    verify_password,
+    get_password_hash,
+    create_access_token,
+    create_refresh_token,
+    decode_token
+)
+from app.models.user import User
+from app.schemas.user import UserCreate, UserResponse, UserLogin
+from app.schemas.token import Token
+from app.api.deps import get_current_user
+
+router = APIRouter(prefix="/auth", tags=["authentication"])
+
+
+@router.post("/register", response_model=UserResponse, status_code=status.HTTP_201_CREATED)
+async def register(
+    user_data: UserCreate,
+    db: Annotated[AsyncSession, Depends(get_db)]
+):
+    """Register a new user."""
+    # Check if email already exists
+    result = await db.execute(select(User).where(User.email == user_data.email))
+    existing_user = result.scalar_one_or_none()
+    if existing_user:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail="Email already registered"
+        )
+
+    # Create new user
+    new_user = User(
+        email=user_data.email,
+        password_hash=get_password_hash(user_data.password),
+        name=user_data.name,
+        role="engineer"  # Default role
+    )
+    db.add(new_user)
+    await db.commit()
+    await db.refresh(new_user)
+
+    return new_user
+
+
+@router.post("/login", response_model=Token)
+async def login(
+    form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
+    db: Annotated[AsyncSession, Depends(get_db)]
+):
+    """Login and get access token."""
+    # Find user by email
+    result = await db.execute(select(User).where(User.email == form_data.username))
+    user = result.scalar_one_or_none()
+
+    if not user or not verify_password(form_data.password, user.password_hash):
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect email or password",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+
+    # Update last login
+    user.last_login = datetime.now(timezone.utc)
+    await db.commit()
+
+    # Create tokens
+    access_token = create_access_token(data={"sub": str(user.id)})
+    refresh_token = create_refresh_token(data={"sub": str(user.id)})
+
+    return Token(
+        access_token=access_token,
+        refresh_token=refresh_token,
+        token_type="bearer"
+    )
+
+
+@router.post("/login/json", response_model=Token)
+async def login_json(
+    credentials: UserLogin,
+    db: Annotated[AsyncSession, Depends(get_db)]
+):
+    """Login with JSON body (alternative to form data)."""
+    result = await db.execute(select(User).where(User.email == credentials.email))
+    user = result.scalar_one_or_none()
+
+    if not user or not verify_password(credentials.password, user.password_hash):
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect email or password"
+        )
+
+    user.last_login = datetime.now(timezone.utc)
+    await db.commit()
+
+    access_token = create_access_token(data={"sub": str(user.id)})
+    refresh_token = create_refresh_token(data={"sub": str(user.id)})
+
+    return Token(
+        access_token=access_token,
+        refresh_token=refresh_token,
+        token_type="bearer"
+    )
+
+
+@router.post("/refresh", response_model=Token)
+async def refresh_token(
+    refresh_token: str,
+    db: Annotated[AsyncSession, Depends(get_db)]
+):
+    """Refresh access token using refresh token."""
+    payload = decode_token(refresh_token)
+    if payload is None or payload.get("type") != "refresh":
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid refresh token"
+        )
+
+    user_id = payload.get("sub")
+    result = await db.execute(select(User).where(User.id == user_id))
+    user = result.scalar_one_or_none()
+
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="User not found"
+        )
+
+    access_token = create_access_token(data={"sub": str(user.id)})
+    new_refresh_token = create_refresh_token(data={"sub": str(user.id)})
+
+    return Token(
+        access_token=access_token,
+        refresh_token=new_refresh_token,
+        token_type="bearer"
+    )
+
+
+@router.get("/me", response_model=UserResponse)
+async def get_me(
+    current_user: Annotated[User, Depends(get_current_user)]
+):
+    """Get current authenticated user."""
+    return current_user
+
+
+@router.post("/logout")
+async def logout():
+    """Logout user (client should discard tokens)."""
+    # JWT tokens are stateless, so logout is handled client-side
+    # In a production app, you might want to blacklist the token
+    return {"message": "Successfully logged out"}