#![cfg(test)]

use crate::{timeago::TimeUnit};
use fancy_regex::Regex;
use once_cell::sync::Lazy;

const TARGET_FILE: &str = "src/dictionary.rs";

fn parse_tu(tu: &str) -> (u8, Option<TimeUnit>) {
    static TU_PATTERN: Lazy<Regex> = Lazy::new(|| Regex::new(r"^(\d*)(\w?)$").unwrap());
    match TU_PATTERN.captures(tu).unwrap() {
        Some(cap) => (
            cap.get(1).unwrap().as_str().parse().unwrap_or(1),
            match cap.get(2).unwrap().as_str() {
                "s" => Some(TimeUnit::Second),
                "m" => Some(TimeUnit::Minute),
                "h" => Some(TimeUnit::Hour),
                "D" => Some(TimeUnit::Day),
                "W" => Some(TimeUnit::Week),
                "M" => Some(TimeUnit::Month),
                "Y" => Some(TimeUnit::Year),
                "" => None,
                _ => panic!("invalid time unit: {}", tu),
            },
        ),
        None => panic!("invalid time unit: {}", tu),
    }
}

// #[test]
fn generate_dictionary() {
    let dict = super::read_dict();

    let code_head = r#"// This file is automatically generated. DO NOT EDIT.
use crate::{
    model::Language,
    timeago::{TaToken, TimeUnit},
};

pub struct Entry {
    pub timeago_tokens: phf::Map<&'static str, TaToken>,
    pub date_order: &'static str,
    pub months: phf::Map<&'static str, u8>,
}
"#;

    let mut code_timeago_tokens = r#"#[rustfmt::skip]
pub fn entry(lang: Language) -> Entry {
    match lang {
        "#
    .to_owned();

    dict.iter().for_each(|(lang, entry)| {
        // Match selector
        let mut selector = format!("Language::{:?}", lang);
        entry.equivalent.iter().for_each(|eq| {
            selector += &format!(" | Language::{:?}", eq);
        });

        // Timeago tokens
        let mut ta_tokens = phf_codegen::Map::<&str>::new();
        entry.timeago_tokens.iter().for_each(|(txt, tu_str)| {
            let (n, unit) = parse_tu(&tu_str);
            match unit {
                Some(unit) => ta_tokens.entry(
                    &txt,
                    &format!("TaToken {{ n: {}, unit: Some(TimeUnit::{:?}) }}", n, unit),
                ),
                None => ta_tokens.entry(&txt, &format!("TaToken {{ n: {}, unit: None }}", n)),
            };
        });

        // Months
        let mut months = phf_codegen::Map::<&str>::new();
        entry.months.iter().for_each(|(txt, n_mon)| {
            months.entry(&txt, &n_mon.to_string());
        });

        let code_ta_tokens = &ta_tokens.build().to_string().replace('\n', "\n            ");
        let code_months = &months.build().to_string().replace('\n', "\n            ");

        code_timeago_tokens += &format!(
            "{} => Entry {{\n            timeago_tokens: {},\n            date_order: \"{}\",\n            months: {},\n        }},\n        ",
            selector, code_ta_tokens, entry.date_order, code_months
        );
    });

    code_timeago_tokens = code_timeago_tokens.trim_end().to_owned() + "\n    }\n}\n";

    let code = format!("{}\n{}", code_head, code_timeago_tokens);

    std::fs::write(TARGET_FILE, code).unwrap();
}