{{
    const dotUtils = require('./dotUtils.js');
    const champions = require('./.champion.json')
        .filter(({ id }) => id > 0)
        .sortBy(({ name }) => name);

    const constName = name => dotUtils.changeCase.constantCase(name).replace(/[^_A-Z0-9]+/g, '');
    const constNamePad = 12;
}}{{= dotUtils.preamble() }}

newtype_enum! {
    /// A League of Legends champion.
    ///
    /// This newtype acts as a C-like enum; each variant corresponds to an
    /// integer value. Using a newtype allows _unknown_ variants to be
    /// represented. This is important when Riot adds new champions.
    ///
    /// Field | Name | Identifier | Id
    /// ---|---|---|---
{{
    for (const { id, alias, name } of champions) {
}}
    /// `{{= constName(name) }}` | "{{= name }}" | "{{= alias }}" | {{= id }}
{{
    }
}}
    #[derive(serde::Serialize, serde::Deserialize)]
    #[serde(transparent)]
    pub newtype_enum Champion(i16) {
{{
    for (const { id, alias, name } of champions) {
}}
        /// `{{= id }}`.
        {{= constName(name) }} = {{= id }},
{{
    }
}}
    }
}

impl Champion {
    /// The champion's name (`en_US` localization).
    pub const fn name(self) -> Option<&'static str> {
        match self {
{{
    for (const { name } of champions) {
}}
            Self::{{= constName(name).padEnd(constNamePad) }} => Some("{{= name }}"),
{{
    }
}}
            _ => None,
        }
    }

    /// The champion's identifier key. Somtimes called "key", "identifier", or "alias".
    /// This is mainly used in DDragon paths.
    ///
    /// This is generally the `en_US` name with spaces and punctuation removed,
    /// capitalization preserved, however the follow are exceptions:
    ///
    /// Field | Name | Identifier | Id
    /// ---|---|---|---
{{
    for (const { id, alias, name } of champions) {
        if (name.replace(/[^a-zA-Z0-9]+/, '') !== alias) {
}}
    /// `{{= constName(name) }}` | "{{= name }}" | "{{= alias }}" | {{= id }}
{{
        }
    }
}}
    pub const fn identifier(self) -> Option<&'static str> {
        match self {
{{
    for (const { name, alias } of champions) {
}}
            Self::{{= constName(name).padEnd(constNamePad) }} => Some("{{= alias }}"),
{{
    }
}}
            _ => None,
        }
    }

    /// https://github.com/MingweiSamuel/Riven/issues/36
    pub(crate) fn serialize_result<S>(
        val: &Result<Self, std::num::TryFromIntError>,
        serializer: S,
    ) -> Result<S::Ok, S::Error>
    where
        S: serde::ser::Serializer,
    {
        use serde::ser::Serialize;
        val.unwrap_or(Champion(-1)).serialize(serializer)
    }

    /// https://github.com/MingweiSamuel/Riven/issues/36
    pub(crate) fn deserialize_result<'de, D>(
        deserializer: D,
    ) -> Result<Result<Self, std::num::TryFromIntError>, D::Error>
    where
        D: serde::de::Deserializer<'de>,
    {
        use std::convert::TryInto;
        <i64 as serde::de::Deserialize>::deserialize(deserializer).map(|id| id.try_into().map(Self))
    }
}

/// The error used for failures in [`Champion::from_str`].
///
/// Currently only internally stores the four characters used to parse the
/// champion, but may change in the future.
#[derive(Debug)]
pub struct ParseChampionError([char; 4]);
impl std::fmt::Display for ParseChampionError {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        let s: String = self.0.iter().copied().take_while(|&c| '\0' != c).collect();
        write!(f, "Failed to parse unknown champion prefix: {:?}", s)
    }
}
impl std::error::Error for ParseChampionError {}

impl std::str::FromStr for Champion {
    type Err = ParseChampionError;
    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let mut chars = ['\0'; 4];
        s.chars()
            .take(4)
            .filter(|c| c.is_ascii_alphanumeric())
            .map(|c| c.to_ascii_uppercase())
            .enumerate()
            .for_each(|(i, c)| chars[i] = c);
        match chars {
{{
    const keyStrings = (name, alias) => new Set([].concat(...[ name, alias ].map(s => s.toUpperCase())
        .map(s => [
            s.replace(/[^A-Z0-9]+/, '').substring(0, 4),
            s.split(/[^A-Z0-9]/, 1)[0].substring(0, 4),
            s.split(/[^A-Z]/, 1)[0].substring(0, 4),
        ])));
    for (const { id, alias, name } of champions) {
        for (const prefix of keyStrings(name, alias)) {
            const chars = Object.assign(Array(4).fill('\\0'), Array.from(prefix))
                .map(c => `'${c}'`)
                .map(c => c.padStart(4));
}}
            /* {{= prefix.padEnd(4) }} */ [{{= chars.join(', ') }}] => Ok(Champion::{{= constName(name) }}),
{{
        }
    }
}}
            unknown => Err(ParseChampionError(unknown)),
        }
    }
}

impl std::convert::TryFrom<&str> for Champion {
    type Error = <Self as std::str::FromStr>::Err;
    fn try_from(value: &str) -> Result<Self, Self::Error> {
        <Self as std::str::FromStr>::from_str(value)
    }
}