use secrecy::ExposeSecret;
use sqlx::{query, query_as, Connection, SqliteConnection};

use crate::secrets::UserToken;

// TODO: allow configuring this via envar
const DB_URI_DEFAULT: &str = "sqlite://sqlite.db";

const TABLE_USER_TOKENS: &str = "user_tokens";

pub trait Database {
    async fn get_token(&mut self, username: &str) -> Result<UserToken, sqlx::Error>;

    async fn save_token(&mut self, username: &str, token: &UserToken) -> Result<(), sqlx::Error>;
}

#[derive(Debug)]
pub struct SqliteDatabase {
    conn: SqliteConnection,
}

impl SqliteDatabase {
    pub async fn open() -> Self {
        let mut db = Self {
            conn: SqliteConnection::connect(DB_URI_DEFAULT)
                .await
                .expect("Failed to open SQLite database"),
        };

        db.init().await;

        db
    }

    pub async fn init(&mut self) {
        query(
            "CREATE TABLE IF NOT EXISTS {TABLE_USER_TOKENS} (
                id          INTEGER PRIMARY KEY AUTOINCREMENT,
                username    VARCHAR(255) NOT NULL,
                token       NCHAR(30) NOT NULL,
                valid       BOOLEAN NOT NULL,
                created     DATETIME NOT NULL,
                last_used   DATETIME
            )",
        )
        .execute(&mut self.conn)
        .await
        .expect("Failed to initialize table user_tokens");
    }
}

impl Database for SqliteDatabase {
    // TODO: distinguish between invalid token and SQLX error
    async fn get_token(&mut self, username: &str) -> Result<UserToken, sqlx::Error> {
        let row: (String,) = query_as(
            "SELECT token
            FROM user_tokens
            WHERE
                username = ?
                AND valid = TRUE
            ORDER BY
                created DESC",
        )
        .bind(username)
        .fetch_one(&mut self.conn)
        .await?;

        Ok(UserToken::from(row.0))
    }

    async fn save_token(&mut self, username: &str, token: &UserToken) -> Result<(), sqlx::Error> {
        query(
            "INSERT INTO {TABLE_USER_TOKENS}
                (username, token, created, valid)
            VALUES
                (?, ?, DATETIME('NOW'), TRUE)
            ",
        )
        .bind(username)
        .bind(token.0.expose_secret())
        .execute(&mut self.conn)
        .await?;

        Ok(())
    }
}