ggen-api 5.1.0

//! Authentication handlers

use axum::{
    extract::State,
    http::StatusCode,
    Json,
};
use uuid::Uuid;

use crate::{
    error::{ApiError, ApiResult},
    models::{CreateApiKeyRequest, ApiKeyResponse, LoginRequest, LoginResponse, RegisterRequest},
    state::AppState,
};

/// User registration
pub async fn register(
    State(_state): State<AppState>,
    Json(req): Json<RegisterRequest>,
) -> ApiResult<(StatusCode, Json<LoginResponse>)> {
    // TODO: Validate request (email format, password requirements, etc.)
    // TODO: Check if user exists
    // TODO: Hash password
    // TODO: Insert user into database
    // TODO: Generate JWT token

    let token = generate_jwt_token(&req.email, "free");

    Ok((
        StatusCode::CREATED,
        Json(LoginResponse {
            token,
            user_id: Uuid::new_v4().to_string(),
            username: req.username,
            email: req.email,
            tier: "free".to_string(),
            expires_in_secs: 86400 * 30, // 30 days
        }),
    ))
}

/// User login
pub async fn login(
    State(_state): State<AppState>,
    Json(req): Json<LoginRequest>,
) -> ApiResult<Json<LoginResponse>> {
    // TODO: Validate request (email format, password requirements, etc.)
    // TODO: Look up user by email
    // TODO: Verify password hash
    // TODO: Retrieve user tier from database
    // TODO: Generate JWT token

    let token = generate_jwt_token(&req.email, "free");

    Ok(Json(LoginResponse {
        token,
        user_id: Uuid::new_v4().to_string(),
        username: "user".to_string(),
        email: req.email,
        tier: "free".to_string(),
        expires_in_secs: 86400 * 30,
    }))
}

/// Create a new API key
pub async fn create_api_key(
    State(_state): State<AppState>,
    Json(req): Json<CreateApiKeyRequest>,
) -> ApiResult<(StatusCode, Json<ApiKeyResponse>)> {
    // TODO: Validate request (name format, expiration, etc.)
    // TODO: Generate cryptographically secure API key
    // TODO: Hash the key before storing
    // TODO: Insert into database with expiration
    // TODO: Return unhashed key (only shown once)

    let key_id = Uuid::new_v4().to_string();
    let key = format!("ggen_key_{}", Uuid::new_v4().to_string().replace("-", ""));

    Ok((
        StatusCode::CREATED,
        Json(ApiKeyResponse {
            id: key_id,
            key: key.clone(),
            name: req.name,
            created_at: chrono::Utc::now(),
            expires_at: req.expires_in_days.map(|days| {
                chrono::Utc::now() + chrono::Duration::days(days as i64)
            }),
        }),
    ))
}

/// List API keys (metadata only, not actual keys)
pub async fn list_api_keys(
    State(_state): State<AppState>,
) -> ApiResult<Json<serde_json::Value>> {
    // TODO: Get user from auth context
    // TODO: Fetch user's API keys from database (without secret values)

    Ok(Json(serde_json::json!({
        "keys": []
    })))
}

/// Revoke an API key
pub async fn revoke_api_key(
    State(_state): State<AppState>,
    axum::extract::Path(key_id): axum::extract::Path<String>,
) -> ApiResult<StatusCode> {
    if key_id.is_empty() {
        return Err(ApiError::BadRequest("Key ID required".to_string()));
    }

    // TODO: Get user from auth context
    // TODO: Verify ownership of key
    // TODO: Mark key as revoked in database
    // TODO: Invalidate key in cache

    Ok(StatusCode::NO_CONTENT)
}

/// Validate JWT token
pub async fn validate_token(
    State(_state): State<AppState>,
    Json(payload): Json<serde_json::Value>,
) -> ApiResult<Json<serde_json::Value>> {
    let token = payload
        .get("token")
        .and_then(|v| v.as_str())
        .ok_or_else(|| ApiError::BadRequest("Token required".to_string()))?;

    // TODO: Verify JWT signature using configured secret
    // TODO: Check token expiration
    // TODO: Return token claims

    Ok(Json(serde_json::json!({
        "valid": true,
        "user_id": "user123",
        "email": "user@example.com",
        "tier": "free"
    })))
}

// Helper function to generate JWT tokens
fn generate_jwt_token(email: &str, tier: &str) -> String {
    // TODO: Implement proper JWT generation using jsonwebtoken crate
    format!("jwt.{}.{}", email, tier)
}