use rusqlite::{Connection, OptionalExtension, params, Result, Row, ToSql, Transaction};
use serde::Serialize;

use crate::db::_external_id::{Id, SecurityId, UserId};
use crate::db::users::User;

#[derive(Debug, Serialize, PartialEq)]
pub enum SecurityType {
    Currency,
    Bond,
}

impl SecurityType {
    fn from_string(s: String) -> SecurityType {
        if s == "currency".to_string() {
            return SecurityType::Currency;
        }
        if s == "bond".to_string() {
            return SecurityType::Bond;
        }
        panic!("Impossible to convert string {} to SecurityType.", s);
    }
}

impl ToSql for SecurityType {
    #[inline]
    fn to_sql(&self) -> Result<rusqlite::types::ToSqlOutput<'_>> {
        Ok(rusqlite::types::ToSqlOutput::from(match self {
            SecurityType::Currency => "currency",
            SecurityType::Bond => "bond",
        }))
    }
}

#[derive(Debug, Serialize, PartialEq)]
pub struct Security {
    id: i64,
    security_type: SecurityType,
    symbol: String,
}

impl Security {
    pub fn id(&self) -> SecurityId {
        SecurityId::from_id(self.id)
    }
}

impl Security {
    pub fn from_row(row: &Row) -> Result<Security> {
        Ok(Security {
            id: row.get("sec_id")?,
            security_type: SecurityType::from_string(row.get("sec_security_type")?),
            symbol: row.get("sec_symbol")?,
        })
    }
}

pub struct NewSecurity {
    pub security_type: SecurityType,
    pub symbol: String,
    pub name: String,
}

pub fn create_security(tx: &Transaction,
                       sec: &NewSecurity,
                       owner: &UserId) -> Result<Security> {
    let q = "INSERT INTO
                     securities(name, symbol, security_type)
                   VALUES(?1, ?2, ?3)";
    let params = (&sec.name, &sec.symbol, &sec.security_type);
    tx.execute(q, params)?;
    let new_sec_id = tx.last_insert_rowid() as i32;

    return get_security_by_id(tx, new_sec_id);
}


pub fn get_security_by_id(tx: &Transaction, id: i32) -> Result<Security> {
    let q = "SELECT id AS sec_id, security_type AS sec_security_type, symbol AS sec_symbol
                  FROM securities
                  WHERE id = ?1";
    tx.query_row(q, params![id], Security::from_row)
}

pub fn list_securities(conn: &Connection) -> Result<Vec<Security>> {
    let q = "SELECT id AS sec_id, security_type AS sec_security_type, symbol AS sec_symbol
                  FROM securities
                  ORDER BY id ASC";
    let mut stmt = conn.prepare(q)?;

    let ret: Vec<Security> = stmt
        .query_map([], Security::from_row)?
        .filter(Result::is_ok)
        .map(Result::unwrap)
        .collect();
    return Ok(ret);
}


#[cfg(test)]
mod test_securities {
    use rusqlite::{Connection, params};

    use crate::db::_test_utils::*;
    use crate::migration;

    use super::*;

    fn setup() -> (Connection, Vec<User>) {
        let mut conn = Connection::open_in_memory().unwrap();
        migration::apply_migrations(&mut conn).unwrap();
        let tx = conn.transaction().unwrap();
        let users = setup_users(&tx).unwrap();
        tx.commit().unwrap();

        return (conn, users);
    }

    #[test]
    fn test_security_types() -> Result<(), rusqlite::Error> {
        let (mut conn, users) = setup();
        let q = "CREATE TABLE test_security_types(
            name TEXT,
            FOREIGN KEY (name) REFERENCES security_types (name)
        )";
        conn.execute(q, ())?;
        let security_types = vec![SecurityType::Currency, SecurityType::Bond];
        for sec in security_types.iter() {
            let q = "INSERT INTO test_security_types(name) VALUES (?1)";
            conn.execute(q, params![sec])?;
        }
        return Ok(());
    }

    #[test]
    fn test_create_security() -> Result<(), rusqlite::Error> {
        let (mut conn, users) = setup();
        let owner = users.get(0).unwrap();
        let not_owner = users.get(1).unwrap();
        let sec = mock_currency_1();
        let tx = conn.transaction()?;
        let sec = create_security(&tx, &sec, &owner.id())?;

        tx.commit()
    }

    #[test]
    fn test_list_security() -> Result<(), rusqlite::Error> {
        let (mut conn, users) = setup();
        let user = users.get(0).unwrap();
        assert_eq!(0, list_securities(&conn)?.len());

        let sec = mock_currency_1();
        let tx = conn.transaction()?;
        create_security(&tx, &sec, &user.id())?;
        tx.commit()?;
        let ret = list_securities(&conn)?;
        let expt = Security {
            id: 1,
            security_type: SecurityType::Currency,
            symbol: "P".to_string(),
        };
        assert_eq!(1, ret.len());
        assert_eq!(&expt, ret.get(0).unwrap());


        let sec = mock_currency_2();
        let expt = Security {
            id: 2,
            security_type: SecurityType::Bond,
            symbol: "B".to_string(),
        };
        let tx = conn.transaction()?;
        create_security(&tx, &sec, &user.id())?;
        tx.commit()?;
        let ret = list_securities(&conn)?;
        assert_eq!(2, ret.len());
        assert_eq!(&expt, ret.get(1).unwrap());

        return Ok(());
    }
}