use std::fmt::{Debug, Formatter};
use std::io::Write;

use diesel::backend::Backend;
use diesel::deserialize::FromSql;
use diesel::serialize::{IsNull, Output, ToSql};
use diesel::sql_types::Binary;
use diesel::sqlite::Sqlite;
use diesel::{deserialize, serialize};
use serde::{Serialize, Serializer};
use uuid::Uuid;

#[derive(AsExpression, FromSqlRow, PartialEq, Clone)]
#[sql_type = "Binary"]
pub enum EmgauwaUid {
    On,
    Off,
    Any(Uuid),
}

impl Default for EmgauwaUid {
    fn default() -> Self {
        EmgauwaUid::Any(Uuid::new_v4())
    }
}

impl Debug for EmgauwaUid {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        match self {
            EmgauwaUid::On => "on".fmt(f),
            EmgauwaUid::Off => "off".fmt(f),
            EmgauwaUid::Any(value) => value.fmt(f),
        }
    }
}

impl ToSql<Binary, Sqlite> for EmgauwaUid {
    fn to_sql<W: Write>(&self, out: &mut Output<W, Sqlite>) -> serialize::Result {
        match self {
            EmgauwaUid::On => out.write_all(&[1])?,
            EmgauwaUid::Off => out.write_all(&[0])?,
            EmgauwaUid::Any(_) => out.write_all(Uuid::from(self).as_bytes())?,
        }
        Ok(IsNull::No)
    }
}

impl FromSql<Binary, Sqlite> for EmgauwaUid {
    fn from_sql(bytes: Option<&<Sqlite as Backend>::RawValue>) -> deserialize::Result<Self> {
        match bytes {
            None => Ok(EmgauwaUid::default()),
            Some(value) => match value.read_blob() {
                [0] => Ok(EmgauwaUid::Off),
                [1] => Ok(EmgauwaUid::On),
                value_bytes => Ok(EmgauwaUid::Any(Uuid::from_slice(value_bytes).unwrap())),
            },
        }
    }
}

impl Serialize for EmgauwaUid {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        String::from(self).serialize(serializer)
    }
}

impl From<Uuid> for EmgauwaUid {
    fn from(uid: Uuid) -> EmgauwaUid {
        match uid.as_u128() {
            0 => EmgauwaUid::Off,
            1 => EmgauwaUid::On,
            _ => EmgauwaUid::Any(uid),
        }
    }
}

impl From<&EmgauwaUid> for Uuid {
    fn from(emgauwa_uid: &EmgauwaUid) -> Uuid {
        match emgauwa_uid {
            EmgauwaUid::On => uuid::Uuid::from_u128(1),
            EmgauwaUid::Off => uuid::Uuid::from_u128(0),
            EmgauwaUid::Any(value) => *value,
        }
    }
}

impl From<&EmgauwaUid> for String {
    fn from(emgauwa_uid: &EmgauwaUid) -> String {
        match emgauwa_uid {
            EmgauwaUid::Off => String::from("off"),
            EmgauwaUid::On => String::from("on"),
            EmgauwaUid::Any(value) => value.to_hyphenated().to_string(),
        }
    }
}