Fix compilation errors: Add missing dependencies, fix module visibility, and update Axum middleware types

backend/src/handlers/auth.rs

@@ -0,0 +1,108 @@
+use crate::{db::Db, AppState};
+use axum::{
+    extract::{State, Json},
+    http::StatusCode,
+    response::IntoResponse,
+};
+use serde::{Deserialize, Serialize};
+use utoipa::ToSchema;
+use axum_extra::extract::cookie::{Cookie, CookieJar, SameSite};
+use time::Duration;
+
+#[derive(Deserialize, ToSchema)]
+pub struct LoginRequest {
+    username: String,
+    password: String,
+}
+
+#[derive(Serialize)]
+pub struct UserResponse {
+    username: String,
+}
+
+#[utoipa::path(
+    post,
+    path = "/api/auth/login",
+    request_body = LoginRequest,
+    responses(
+        (status = 200, description = "Login successful"),
+        (status = 401, description = "Invalid credentials"),
+        (status = 500, description = "Internal server error")
+    )
+)]
+pub async fn login_handler(
+    State(state): State<AppState>,
+    jar: CookieJar,
+    Json(payload): Json<LoginRequest>,
+) -> impl IntoResponse {
+    let user = match state.db.get_user_by_username(&payload.username).await {
+        Ok(Some(u)) => u,
+        Ok(None) => return (StatusCode::UNAUTHORIZED, "Invalid credentials").into_response(),
+        Err(e) => {
+            tracing::error!("DB error during login: {}", e);
+            return (StatusCode::INTERNAL_SERVER_ERROR, "Database error").into_response();
+        }
+    };
+
+    let (user_id, password_hash) = user;
+
+    match bcrypt::verify(&payload.password, &password_hash) {
+        Ok(true) => {
+            // Create session
+            let token: String = (0..32).map(|_| {
+                use rand::{distributions::Alphanumeric, Rng};
+                rand::thread_rng().sample(Alphanumeric) as char
+            }).collect();
+
+            // Expires in 30 days
+            let expires_in = 60 * 60 * 24 * 30;
+            let expires_at = time::OffsetDateTime::now_utc().unix_timestamp() + expires_in;
+
+            if let Err(e) = state.db.create_session(user_id, &token, expires_at).await {
+                tracing::error!("Failed to create session: {}", e);
+                return (StatusCode::INTERNAL_SERVER_ERROR, "Failed to create session").into_response();
+            }
+
+            let cookie = Cookie::build(("auth_token", token))
+                .path("/")
+                .http_only(true)
+                .same_site(SameSite::Strict)
+                .max_age(Duration::seconds(expires_in))
+                .build();
+
+            (StatusCode::OK, jar.add(cookie), "Login successful").into_response()
+        }
+        _ => (StatusCode::UNAUTHORIZED, "Invalid credentials").into_response(),
+    }
+}
+
+pub async fn logout_handler(
+    State(state): State<AppState>,
+    jar: CookieJar,
+) -> impl IntoResponse {
+    if let Some(token) = jar.get("auth_token") {
+        let _ = state.db.delete_session(token.value()).await;
+    }
+
+    let cookie = Cookie::build(("auth_token", ""))
+        .path("/")
+        .http_only(true)
+        .max_age(Duration::seconds(-1)) // Expire immediately
+        .build();
+
+    (StatusCode::OK, jar.add(cookie), "Logged out").into_response()
+}
+
+pub async fn check_auth_handler(
+    State(state): State<AppState>,
+    jar: CookieJar,
+) -> impl IntoResponse {
+    if let Some(token) = jar.get("auth_token") {
+        match state.db.get_session_user(token.value()).await {
+            Ok(Some(_)) => return StatusCode::OK.into_response(),
+            _ => {} // Invalid session
+        }
+    }
+
+    StatusCode::UNAUTHORIZED.into_response()
+}