use std::collections::HashMap;
use std::fmt;

use futures::future::join_all;
use rss::{GuidBuilder, Item, ItemBuilder};
use serde::Deserialize;
use time::format_description::well_known::iso8601::FormattedComponents;
use time::format_description::well_known::{iso8601, Iso8601};
use time::Date;

use crate::scrapers::page_url;
use crate::{hash, scrapers};

pub mod route;
pub mod template;

#[derive(Clone, Debug, Deserialize)]
pub struct Feed {
    pub title: String,
    pub url: String,
    pub id: String,
}

impl fmt::Display for Feed {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{} ({})", self.title, self.url)
    }
}

#[derive(Clone, Debug, Deserialize)]
pub struct Footprint {
    pub title: String,
    pub text: String,
    pub url: String,
    pub date: Date,
    pub page: u8,
}

const ISO8601_DATE: u128 = iso8601::Config::DEFAULT
    .set_formatted_components(FormattedComponents::Date)
    .encode();

impl Footprint {
    pub fn into_rss_item(self, root_url: &str) -> Item {
        let text = if String::is_empty(&self.text) {
            "No description"
        } else {
            &self.text
        };
        // injection, I know
        let desc = format!(
            "{} <br /><br /> --- <br /><br /> from <a href=\"{}\">page {}</a>",
            text,
            page_url(root_url, self.page),
            self.page
        );
        ItemBuilder::default()
            .title(Some(self.title))
            .pub_date(self.date.format(&Iso8601::<ISO8601_DATE>).ok())
            .link(Some(self.url.clone()))
            .description(Some(desc))
            .guid(Some(GuidBuilder::default().value(self.url).build()))
            .build()
    }
}

pub async fn enrich_feeds(feed_urls: Vec<String>) -> HashMap<String, Feed> {
    let feeds = join_all(feed_urls.iter().map(|feed_url| async {
        let title = scrapers::feed_title(feed_url).await.unwrap();
        let id = hash::fnv_str(feed_url);

        Feed {
            title,
            url: feed_url.clone(),
            id,
        }
    }))
    .await;

    feeds.iter().map(|x| (x.id.clone(), x.clone())).collect()
}