use serde::{Deserialize, Serialize};
use sqlx::Decode;
use strum::{EnumIter, EnumString};

/// Languages represented as
/// [ISO 639-3 codes](https://en.wikipedia.org/wiki/List_of_ISO_639-3_codes).
#[derive(
    Clone, Debug, Decode, Deserialize, strum::Display, PartialEq, Serialize, EnumIter, EnumString,
)]
#[serde(rename_all = "lowercase")]
#[strum(serialize_all = "lowercase")]
// [`sqlx`] implements Decode and Encode to/from the Postgres `TEXT` type based
// on the [`std::fmt::Display`] and [`std::str::FromStr`] traits, so it should
// use the transformations applied by [`strum`].
// <https://docs.rs/sqlx/latest/sqlx/types/struct.Text.html>
pub enum Language {
    Deu,
    Eng,
    Spa,
}

impl Default for Language {
    /// Language defaults to English when necessary, as the product is being
    /// developed with a primarily English speaking/reading/writing market in
    /// mind.
    fn default() -> Self {
        Self::Eng
    }
}

impl Language {
    pub fn as_locale_str(&self) -> &'static str {
        match self {
            Self::Deu => "Deutsch",
            Self::Eng => "English",
            Self::Spa => "Español",
        }
    }
}