monorepo/visions/server/src/database.rs

use std::path::Path;

use async_std::channel::{bounded, Receiver, Sender};
use async_trait::async_trait;
use include_dir::{include_dir, Dir};
use lazy_static::lazy_static;
use result_extended::{error, fatal, ok, return_error, ResultExt};
use rusqlite::{types::{FromSql, FromSqlResult, ValueRef}, Connection};
use rusqlite_migration::Migrations;
use serde::{Deserialize, Serialize};
use thiserror::Error;
use uuid::Uuid;

use crate::types::FatalError;

static MIGRATIONS_DIR: Dir = include_dir!("$CARGO_MANIFEST_DIR/migrations");

lazy_static! {
    static ref MIGRATIONS: Migrations<'static> =
        Migrations::from_directory(&MIGRATIONS_DIR).unwrap();
}

#[derive(Debug, Error)]
pub enum Error {
    #[error("No response to request")]
    NoResponse,
}

#[derive(Debug)]
enum Request {
    Charsheet(CharacterId),
    Games,
    Users,
}

#[derive(Debug)]
struct DatabaseRequest {
    tx: Sender<DatabaseResponse>,
    req: Request,
}

#[derive(Debug)]
enum DatabaseResponse {
    Charsheet(Option<CharsheetRow>),
    Games(Vec<GameRow>),
    Users(Vec<UserRow>),
}

#[derive(Clone, Debug, Deserialize, Eq, Hash, PartialEq, Serialize)]
pub struct UserId(String);

impl UserId {
    pub fn new() -> Self {
        Self(format!("{}", Uuid::new_v4().hyphenated()))
    }

    pub fn as_str<'a>(&'a self) -> &'a str {
        &self.0
    }
}

impl From<&str> for UserId {
    fn from(s: &str) -> Self {
        Self(s.to_owned())
    }
}

impl From<String> for UserId {
    fn from(s: String) -> Self {
        Self(s)
    }
}

impl FromSql for UserId {
    fn column_result(value: ValueRef<'_>) -> FromSqlResult<Self> {
        match value {
            ValueRef::Text(text) => Ok(Self::from(String::from_utf8(text.to_vec()).unwrap())),
            _ => unimplemented!(),
        }
    }
}

#[derive(Clone, Debug, Deserialize, Eq, Hash, PartialEq, Serialize)]
pub struct GameId(String);

impl GameId {
    pub fn new() -> Self {
        Self(format!("{}", Uuid::new_v4().hyphenated()))
    }

    pub fn as_str<'a>(&'a self) -> &'a str {
        &self.0
    }
}

impl From<&str> for GameId {
    fn from(s: &str) -> Self {
        Self(s.to_owned())
    }
}

impl From<String> for GameId {
    fn from(s: String) -> Self {
        Self(s)
    }
}

impl FromSql for GameId {
    fn column_result(value: ValueRef<'_>) -> FromSqlResult<Self> {
        match value {
            ValueRef::Text(text) => Ok(Self::from(String::from_utf8(text.to_vec()).unwrap())),
            _ => unimplemented!(),
        }
    }
}

#[derive(Clone, Debug, Deserialize, Eq, Hash, PartialEq, Serialize)]
pub struct CharacterId(String);

impl CharacterId {
    pub fn new() -> Self {
        Self(format!("{}", Uuid::new_v4().hyphenated()))
    }

    pub fn as_str<'a>(&'a self) -> &'a str {
        &self.0
    }
}

impl From<&str> for CharacterId {
    fn from(s: &str) -> Self {
        Self(s.to_owned())
    }
}

impl From<String> for CharacterId {
    fn from(s: String) -> Self {
        Self(s)
    }
}

impl FromSql for CharacterId {
    fn column_result(value: ValueRef<'_>) -> FromSqlResult<Self> {
        match value {
            ValueRef::Text(text) => Ok(Self::from(String::from_utf8(text.to_vec()).unwrap())),
            _ => unimplemented!(),
        }
    }
}

#[derive(Clone, Debug)]
pub struct UserRow {
    pub id: UserId,
    pub name: String,
    pub password: String,
    pub admin: bool,
    pub enabled: bool,
}

#[derive(Clone, Debug)]
pub struct Role {
    userid: UserId,
    gameid: GameId,
    role: String,
}

#[derive(Clone, Debug)]
pub struct GameRow {
    pub id: UserId,
    pub name: String,
}

#[derive(Clone, Debug)]
pub struct CharsheetRow {
    id: String,
    game: GameId,
    pub data: serde_json::Value,
}

#[async_trait]
pub trait Database: Send + Sync {
    async fn users(&mut self) -> result_extended::ResultExt<Vec<UserRow>, Error, FatalError>;

    async fn games(&mut self) -> result_extended::ResultExt<Vec<GameRow>, Error, FatalError>;

    async fn character(
        &mut self,
        id: CharacterId,
    ) -> result_extended::ResultExt<Option<CharsheetRow>, Error, FatalError>;
}

pub struct DiskDb {
    conn: Connection,
}

fn setup_test_database(conn: &Connection) -> Result<(), FatalError> {
    let mut gamecount_stmt = conn.prepare("SELECT count(*) FROM games").unwrap();
    let mut count = gamecount_stmt.query([]).unwrap();
    if count.next().unwrap().unwrap().get::<usize, usize>(0) == Ok(0) {
        let admin_id = format!("{}", Uuid::new_v4());
        let user_id = format!("{}", Uuid::new_v4());
        let game_id = format!("{}", Uuid::new_v4());
        let char_id = CharacterId::new();

        let mut user_stmt = conn
            .prepare("INSERT INTO users VALUES (?, ?, ?, ?, ?)")
            .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
        user_stmt
            .execute((admin_id.clone(), "admin", "abcdefg", true, true))
            .unwrap();
        user_stmt
            .execute((user_id.clone(), "savanni", "abcdefg", false, true))
            .unwrap();

        let mut game_stmt = conn
            .prepare("INSERT INTO games VALUES (?, ?)")
            .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
        game_stmt
            .execute((game_id.clone(), "Circle of Bluest Sky"))
            .unwrap();

        let mut role_stmt = conn
            .prepare("INSERT INTO roles VALUES (?, ?, ?)")
            .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
        role_stmt
            .execute((user_id.clone(), game_id.clone(), "gm"))
            .unwrap();

        let mut sheet_stmt = conn
            .prepare("INSERT INTO characters VALUES (?, ?, ?)")
            .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;

        sheet_stmt.execute((char_id.as_str(), game_id, r#"{ "type_": "Candela", "name": "Soren Jensen", "pronouns": "he/him", "circle": "Circle of the Bluest Sky", "style": "dapper gentleman", "catalyst": "a cursed book", "question": "What were the contents of that book?", "nerve": { "type_": "nerve", "drives": { "current": 1, "max": 2 }, "resistances": { "current": 0, "max": 3 }, "move": { "gilded": false, "score": 2 }, "strike": { "gilded": false, "score": 1 }, "control": { "gilded": true, "score": 0 } }, "cunning": { "type_": "cunning", "drives": { "current": 1, "max": 1 }, "resistances": { "current": 0, "max": 3 }, "sway": { "gilded": false, "score": 0 }, "read": { "gilded": false, "score": 0 }, "hide": { "gilded": false, "score": 0 } }, "intuition": { "type_": "intuition", "drives": { "current": 0, "max": 0 }, "resistances": { "current": 0, "max": 3 }, "survey": { "gilded": false, "score": 0 }, "focus": { "gilded": false, "score": 0 }, "sense": { "gilded": false, "score": 0 } }, "role": "Slink", "role_abilities": [ "Scout: If you have time to observe a location, you can spend 1 Intuition to ask a question: What do I notice here that others do not see? What in this place might be of use to us? What path should we follow?" ], "specialty": "Detective", "specialty_abilities": [ "Mind Palace: When you want to figure out how two clues might relate or what path they should point you towards, burn 1 Intution resistance. The GM will give you the information you have deduced." ] }"#))
                    .unwrap();
    }

    Ok(())
}

impl DiskDb {
    pub fn new<P>(path: Option<P>) -> Result<Self, FatalError>
    where
        P: AsRef<Path>,
    {
        let mut conn = match path {
            None => Connection::open(":memory:").expect("to create a memory connection"),
            Some(path) => Connection::open(path).expect("to create connection"),
        };

        MIGRATIONS
            .to_latest(&mut conn)
            .map_err(|err| FatalError::DatabaseMigrationFailure(format!("{}", err)))?;

        setup_test_database(&conn)?;

        Ok(DiskDb { conn })
    }

    fn users(&self) -> Result<Vec<UserRow>, FatalError> {
        let mut stmt = self.conn.prepare("SELECT * FROM USERS")
            .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
        let items = stmt.query_map([], |row| {
            Ok(UserRow {
                id: row.get(0).unwrap(),
                name: row.get(1).unwrap(),
                password: row.get(2).unwrap(),
                admin: row.get(3).unwrap(),
                enabled: row.get(4).unwrap(),
            })
        }).unwrap().collect::<Result<Vec<UserRow>, rusqlite::Error>>().unwrap();
        Ok(items)
    }

    fn user(&self, id: UserId) -> Result<Option<UserRow>, FatalError> {
        let mut stmt = self
            .conn
            .prepare("SELECT uuid, name, password, admin, enabled WHERE uuid=?")
            .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
        let items: Vec<UserRow> = stmt
            .query_map([id.as_str()], |row| {
                Ok(UserRow {
                    id: row.get(0).unwrap(),
                    name: row.get(1).unwrap(),
                    password: row.get(2).unwrap(),
                    admin: row.get(3).unwrap(),
                    enabled: row.get(4).unwrap(),
                })
            })
            .unwrap()
            .collect::<Result<Vec<UserRow>, rusqlite::Error>>()
            .unwrap();
        match &items[..] {
            [] => Ok(None),
            [item] => Ok(Some(item.clone())),
            _ => Err(FatalError::NonUniqueDatabaseKey(id.as_str().to_owned())),
        }
    }

    fn save_user(
        &self,
        user_id: Option<UserId>,
        name: &str,
        password: &str,
        admin: bool,
        enabled: bool,
    ) -> Result<UserId, FatalError> {
        match user_id {
            None => {
                let user_id = UserId::new();
                let mut stmt = self
                    .conn
                    .prepare("INSERT INTO users VALUES (?, ?, ?, ?, ?)")
                    .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
                stmt.execute((user_id.as_str(), name, password, admin, enabled))
                    .unwrap();
                Ok(user_id)
            }
            Some(user_id) => {
                let mut stmt = self
                    .conn
                    .prepare(
                        "UPDATE users SET name=?, password=?, admin=?, enbabled=? WHERE uuid=?",
                    )
                    .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
                stmt.execute((name, password, admin, enabled, user_id.as_str()))
                    .unwrap();
                Ok(user_id)
            }
        }
    }

    fn save_game(
        &self,
        game_id: Option<GameId>,
        name: &str,
    ) -> Result<GameId, FatalError> {
        match game_id {
            None => {
                let game_id = GameId::new();
                let mut stmt = self
                    .conn
                    .prepare("INSERT INTO games VALUES (?, ?)")
                    .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
                stmt.execute((game_id.as_str(), name))
                    .unwrap();
                Ok(game_id)
            }
            Some(game_id) => {
                let mut stmt = self
                    .conn
                    .prepare(
                        "UPDATE games SET name=? WHERE uuid=?",
                    )
                    .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
                stmt.execute((name, game_id.as_str()))
                    .unwrap();
                Ok(game_id)
            }
        }
    }

    fn character(&self, id: CharacterId) -> Result<Option<CharsheetRow>, FatalError> {
        let mut stmt = self
            .conn
            .prepare("SELECT uuid, game, data FROM characters WHERE uuid=?")
            .map_err(|err| FatalError::ConstructQueryFailure(format!("{}", err)))?;
        let items: Vec<CharsheetRow> = stmt
            .query_map([id.as_str()], |row| {
                let data: String = row.get(2).unwrap();
                Ok(CharsheetRow {
                    id: row.get(0).unwrap(),
                    game: row.get(1).unwrap(),
                    data: serde_json::from_str(&data).unwrap(),
                })
            })
            .unwrap()
            .collect::<Result<Vec<CharsheetRow>, rusqlite::Error>>()
            .unwrap();
        match &items[..] {
            [] => Ok(None),
            [item] => Ok(Some(item.clone())),
            _ => Err(FatalError::NonUniqueDatabaseKey(id.as_str().to_owned())),
        }
    }

    fn save_character(
        &self,
        char_id: Option<CharacterId>,
        game: GameId,
        character: serde_json::Value,
    ) -> std::result::Result<CharacterId, Error> {
        match char_id {
            None => {
                let char_id = CharacterId::new();
                let mut stmt = self
                    .conn
                    .prepare("INSERT INTO characters VALUES (?, ?, ?)")
                    .unwrap();
                stmt.execute((char_id.as_str(), game.as_str(), character.to_string()))
                    .unwrap();

                Ok(char_id)
            }
            Some(char_id) => {
                let mut stmt = self
                    .conn
                    .prepare("UPDATE characters SET data=? WHERE uuid=?")
                    .unwrap();
                stmt.execute((character.to_string(), char_id.as_str()))
                    .unwrap();

                Ok(char_id)
            }
        }
    }
}

async fn db_handler(db: DiskDb, requestor: Receiver<DatabaseRequest>) {
    while let Ok(DatabaseRequest { tx, req }) = requestor.recv().await {
        println!("Request received: {:?}", req);
        match req {
            Request::Charsheet(id) => {
                let sheet = db.character(id);
                println!("sheet retrieved: {:?}", sheet);
                match sheet {
                    Ok(sheet) => {
                        tx.send(DatabaseResponse::Charsheet(sheet)).await.unwrap();
                    }
                    _ => unimplemented!(),
                }
            }
            Request::Games => {
                unimplemented!();
            }
            Request::Users => {
                let users = db.users();
                match users {
                    Ok(users) => {
                        tx.send(DatabaseResponse::Users(users)).await.unwrap();
                    }
                    _ => unimplemented!(),
                }
            }
        }
    }
    println!("ending db_handler");
}

pub struct DbConn {
    conn: Sender<DatabaseRequest>,
    handle: tokio::task::JoinHandle<()>,
}

impl DbConn {
    pub fn new<P>(path: Option<P>) -> Self
    where
        P: AsRef<Path>,
    {
        let (tx, rx) = bounded::<DatabaseRequest>(5);
        let db = DiskDb::new(path).unwrap();

        let handle = tokio::spawn(async move {
            db_handler(db, rx).await;
        });

        Self { conn: tx, handle }
    }
}

#[async_trait]
impl Database for DbConn {
    async fn users(&mut self) -> ResultExt<Vec<UserRow>, Error, FatalError> {
        let (tx, rx) = bounded::<DatabaseResponse>(1);

        let request = DatabaseRequest {
            tx,
            req: Request::Users,
        };

        match self.conn.send(request).await {
            Ok(()) => (),
            Err(_) => return fatal(FatalError::DatabaseConnectionLost),
        };

        match rx.recv().await {
            Ok(DatabaseResponse::Users(lst)) => ok(lst),
            Ok(_) => fatal(FatalError::MessageMismatch),
            Err(_) => error(Error::NoResponse),
        }
    }

    async fn games(&mut self) -> result_extended::ResultExt<Vec<GameRow>, Error, FatalError> {
        let (tx, rx) = bounded::<DatabaseResponse>(1);

        let request = DatabaseRequest {
            tx,
            req: Request::Games,
        };

        match self.conn.send(request).await {
            Ok(()) => (),
            Err(_) => return fatal(FatalError::DatabaseConnectionLost),
        };

        match rx.recv().await {
            Ok(DatabaseResponse::Games(lst)) => ok(lst),
            Ok(_) => fatal(FatalError::MessageMismatch),
            Err(_) => error(Error::NoResponse),
        }
    }

    async fn character(
        &mut self,
        id: CharacterId,
    ) -> ResultExt<Option<CharsheetRow>, Error, FatalError> {
        let (tx, rx) = bounded::<DatabaseResponse>(1);

        let request = DatabaseRequest {
            tx,
            req: Request::Charsheet(id),
        };

        match self.conn.send(request).await {
            Ok(()) => (),
            Err(_) => return fatal(FatalError::DatabaseConnectionLost),
        };

        match rx.recv().await {
            Ok(DatabaseResponse::Charsheet(row)) => ok(row),
            Ok(_) => fatal(FatalError::MessageMismatch),
            Err(_err) => error(Error::NoResponse),
        }
    }
}

#[cfg(test)]
mod test {
    use std::path::PathBuf;

    use cool_asserts::assert_matches;

    use super::*;

    const soren: &'static str = r#"{ "type_": "Candela", "name": "Soren Jensen", "pronouns": "he/him", "circle": "Circle of the Bluest Sky", "style": "dapper gentleman", "catalyst": "a cursed book", "question": "What were the contents of that book?", "nerve": { "type_": "nerve", "drives": { "current": 1, "max": 2 }, "resistances": { "current": 0, "max": 3 }, "move": { "gilded": false, "score": 2 }, "strike": { "gilded": false, "score": 1 }, "control": { "gilded": true, "score": 0 } }, "cunning": { "type_": "cunning", "drives": { "current": 1, "max": 1 }, "resistances": { "current": 0, "max": 3 }, "sway": { "gilded": false, "score": 0 }, "read": { "gilded": false, "score": 0 }, "hide": { "gilded": false, "score": 0 } }, "intuition": { "type_": "intuition", "drives": { "current": 0, "max": 0 }, "resistances": { "current": 0, "max": 3 }, "survey": { "gilded": false, "score": 0 }, "focus": { "gilded": false, "score": 0 }, "sense": { "gilded": false, "score": 0 } }, "role": "Slink", "role_abilities": [ "Scout: If you have time to observe a location, you can spend 1 Intuition to ask a question: What do I notice here that others do not see? What in this place might be of use to us? What path should we follow?" ], "specialty": "Detective", "specialty_abilities": [ "Mind Palace: When you want to figure out how two clues might relate or what path they should point you towards, burn 1 Intution resistance. The GM will give you the information you have deduced." ] }"#;

    fn setup_db() -> (DiskDb, GameId) {
        let no_path: Option<PathBuf> = None;
        let db = DiskDb::new(no_path).unwrap();

        db.save_user(None, "admin", "abcdefg", true, true);
        let game_id = db.save_game(None, "Candela").unwrap();
        (db, game_id)
    }

    #[test]
    fn it_can_retrieve_a_character() {
        let (db, game_id) = setup_db();

        assert_matches!(db.character(CharacterId::from("1")), Ok(None));

        let js: serde_json::Value = serde_json::from_str(soren).unwrap();
        let soren_id = db
            .save_character(None, game_id, js.clone())
            .unwrap();
        assert_matches!(db.character(soren_id).unwrap(), Some(CharsheetRow{ data, .. }) => assert_eq!(js, data));
    }

    #[tokio::test]
    async fn it_can_retrieve_a_character_through_conn() {
        let memory_db: Option<PathBuf> = None;
        let mut conn = DbConn::new(memory_db);

        assert_matches!(
            conn.character(CharacterId::from("1")).await,
            ResultExt::Ok(None)
        );
    }
}