Implement authentication system with SQLite: Add login/setup pages, auth middleware, and database integration

backend/src/db.rs

@@ -0,0 +1,106 @@
+use sqlx::{sqlite::SqlitePoolOptions, Pool, Sqlite, Row};
+use std::time::Duration;
+use anyhow::Result;
+
+#[derive(Clone)]
+pub struct Db {
+    pool: Pool<Sqlite>,
+}
+
+impl Db {
+    pub async fn new(db_url: &str) -> Result<Self> {
+        let pool = SqlitePoolOptions::new()
+            .max_connections(5)
+            .acquire_timeout(Duration::from_secs(3))
+            .connect(db_url)
+            .await?;
+
+        let db = Self { pool };
+        db.init().await?;
+        Ok(db)
+    }
+
+    async fn init(&self) -> Result<()> {
+        // Create users table
+        sqlx::query(
+            "CREATE TABLE IF NOT EXISTS users (
+                id INTEGER PRIMARY KEY,
+                username TEXT NOT NULL UNIQUE,
+                password_hash TEXT NOT NULL,
+                created_at DATETIME DEFAULT CURRENT_TIMESTAMP
+            )",
+        )
+        .execute(&self.pool)
+        .await?;
+
+        // Create sessions table
+        sqlx::query(
+            "CREATE TABLE IF NOT EXISTS sessions (
+                token TEXT PRIMARY KEY,
+                user_id INTEGER NOT NULL,
+                expires_at DATETIME NOT NULL,
+                FOREIGN KEY(user_id) REFERENCES users(id)
+            )",
+        )
+        .execute(&self.pool)
+        .await?;
+
+        Ok(())
+    }
+
+    // --- User Operations ---
+
+    pub async fn create_user(&self, username: &str, password_hash: &str) -> Result<()> {
+        sqlx::query("INSERT INTO users (username, password_hash) VALUES (?, ?)")
+            .bind(username)
+            .bind(password_hash)
+            .execute(&self.pool)
+            .await?;
+        Ok(())
+    }
+
+    pub async fn get_user_by_username(&self, username: &str) -> Result<Option<(i64, String)>> {
+        let row = sqlx::query("SELECT id, password_hash FROM users WHERE username = ?")
+            .bind(username)
+            .fetch_optional(&self.pool)
+            .await?;
+
+        Ok(row.map(|r| (r.get(0), r.get(1))))
+    }
+
+    pub async fn has_users(&self) -> Result<bool> {
+        let row: (i64,) = sqlx::query_as("SELECT COUNT(*) FROM users")
+            .fetch_one(&self.pool)
+            .await?;
+        Ok(row.0 > 0)
+    }
+
+    // --- Session Operations ---
+
+    pub async fn create_session(&self, user_id: i64, token: &str, expires_at: i64) -> Result<()> {
+        sqlx::query("INSERT INTO sessions (token, user_id, expires_at) VALUES (?, ?, datetime(?, 'unixepoch'))")
+            .bind(token)
+            .bind(user_id)
+            .bind(expires_at)
+            .execute(&self.pool)
+            .await?;
+        Ok(())
+    }
+
+    pub async fn get_session_user(&self, token: &str) -> Result<Option<i64>> {
+        let row = sqlx::query("SELECT user_id FROM sessions WHERE token = ? AND expires_at > datetime('now')")
+            .bind(token)
+            .fetch_optional(&self.pool)
+            .await?;
+
+        Ok(row.map(|r| r.get(0)))
+    }
+
+    pub async fn delete_session(&self, token: &str) -> Result<()> {
+        sqlx::query("DELETE FROM sessions WHERE token = ?")
+            .bind(token)
+            .execute(&self.pool)
+            .await?;
+        Ok(())
+    }
+}