use anyhow::Result;
use chrono::Utc;
use sqlx::SqlitePool;
use uuid::Uuid;

#[derive(Debug, Clone, sqlx::FromRow)]
pub struct AdminSessionRow {
    pub session_id: String,
    pub did: String,
    pub handle: String,
    pub oauth_session_id: String,
    pub created_at: String,
    pub expires_at: String,
}

/// Creates a new admin session and returns the generated session_id.
pub async fn create_session(
    pool: &SqlitePool,
    did: &str,
    handle: &str,
    oauth_session_id: &str,
    ttl_hours: u64,
) -> Result<String> {
    let session_id = Uuid::new_v4().to_string();
    let now = Utc::now();
    let created_at = now.to_rfc3339();
    let expires_at = (now + chrono::Duration::hours(ttl_hours as i64)).to_rfc3339();

    sqlx::query(
        "INSERT INTO admin_sessions (session_id, did, handle, oauth_session_id, created_at, expires_at) VALUES (?, ?, ?, ?, ?, ?)",
    )
    .bind(&session_id)
    .bind(did)
    .bind(handle)
    .bind(oauth_session_id)
    .bind(&created_at)
    .bind(&expires_at)
    .execute(pool)
    .await?;

    Ok(session_id)
}

/// Looks up a session by ID. Returns None if the session does not exist or has expired.
pub async fn get_session(pool: &SqlitePool, session_id: &str) -> Result<Option<AdminSessionRow>> {
    let now = Utc::now().to_rfc3339();

    let row = sqlx::query_as::<_, AdminSessionRow>(
        "SELECT session_id, did, handle, oauth_session_id, created_at, expires_at FROM admin_sessions WHERE session_id = ? AND expires_at > ?",
    )
    .bind(session_id)
    .bind(&now)
    .fetch_optional(pool)
    .await?;

    Ok(row)
}

/// Deletes a session by ID.
pub async fn delete_session(pool: &SqlitePool, session_id: &str) -> Result<()> {
    sqlx::query("DELETE FROM admin_sessions WHERE session_id = ?")
        .bind(session_id)
        .execute(pool)
        .await?;

    Ok(())
}

/// Deletes all expired sessions and returns the number of rows removed.
pub async fn cleanup_expired_sessions(pool: &SqlitePool) -> Result<u64> {
    let now = Utc::now().to_rfc3339();

    let result = sqlx::query("DELETE FROM admin_sessions WHERE expires_at <= ?")
        .bind(&now)
        .execute(pool)
        .await?;

    Ok(result.rows_affected())
}