use chrono::{DateTime, Locale, Utc};
use lazy_static::lazy_static;
use regex::{Captures, Regex};
use std::{collections::HashSet, fmt::Display};

use crate::markup::SPOILER_REGEX;

lazy_static! {
    static ref MARKUP_QUOTE_REGEX: Regex =
        Regex::new(r#"<a class="quote" href=".+">&gt;&gt;(\d+)<\/a>"#).unwrap();
}

pub fn czech_humantime(time: &DateTime<Utc>) -> askama::Result<String> {
    let duration = (Utc::now() - *time).abs();

    let seconds = duration.num_seconds();
    let minutes = duration.num_minutes();
    let hours = duration.num_hours();
    let days = duration.num_days();
    let weeks = duration.num_weeks();
    let months = duration.num_days() / 30;
    let years = duration.num_days() / 365;

    let mut time = "Teď".into();

    if seconds > 0 {
        time = format!(
            "{} {}",
            seconds,
            czech_plural("sekunda|sekundy|sekund", seconds)?
        );
    }

    if minutes > 0 {
        time = format!(
            "{} {}",
            minutes,
            czech_plural("minuta|minuty|minut", minutes)?
        );
    }

    if hours > 0 {
        time = format!("{} {}", hours, czech_plural("hodina|hodiny|hodin", hours)?);
    }

    if days > 0 {
        time = format!("{} {}", days, czech_plural("den|dny|dnů", days)?);
    }

    if weeks > 0 {
        time = format!("{} {}", weeks, czech_plural("týden|týdny|týdnů", weeks)?);
    }

    if months > 0 {
        time = format!(
            "{} {}",
            months,
            czech_plural("měsíc|měsíce|měsíců", months)?
        );
    }

    if years > 0 {
        time = format!("{} {}", years, czech_plural("rok|roky|let", years)?);
    }

    Ok(time)
}

pub fn czech_datetime(time: &DateTime<Utc>) -> askama::Result<String> {
    let time = time
        .format_localized("%d.%m.%Y (%a) %H:%M:%S UTC", Locale::cs_CZ)
        .to_string();

    Ok(time)
}

pub fn czech_plural(plurals: &str, count: impl Display) -> askama::Result<String> {
    let plurals = plurals.split('|').collect::<Vec<_>>();
    let count = count.to_string().parse::<i64>().unwrap();

    let one = plurals[0];
    let few = plurals[1];
    let other = plurals[2];

    if count == 1 {
        Ok(one.into())
    } else if count < 5 {
        Ok(few.into())
    } else {
        Ok(other.into())
    }
}

pub fn inline_post(input: impl Display) -> askama::Result<String> {
    let input = input.to_string();

    if input.is_empty() {
        return Ok("(bez obsahu)".into());
    }

    let collapsed = input.split_whitespace().collect::<Vec<_>>().join(" ");
    let spoilered = SPOILER_REGEX
        .replace_all(&collapsed, "(spoiler)")
        .to_string();

    let truncated = askama::filters::truncate(spoilered, 64)?;

    Ok(truncated)
}

pub fn get_page(input: &usize, page_size: &i64) -> askama::Result<i64> {
    let page = crate::paginate(*page_size, *input as i64);

    Ok(page)
}

pub fn add_yous(
    input: impl Display,
    board: &String,
    yous: &HashSet<String>,
) -> askama::Result<String> {
    let input = input.to_string();

    let output = MARKUP_QUOTE_REGEX.replace_all(&input, |captures: &Captures| {
        let quote = &captures[0];
        let id = &captures[1];

        format!(
            "{}{}",
            quote,
            if yous.contains(&format!("{board}/{id}")) {
                " <span class=\"small\">(Ty)</span>"
            } else {
                ""
            }
        )
    });

    Ok(output.to_string())
}