use std::io::Cursor;
use std::str::FromStr;

use tiny_http::{Header, Response};

use crate::repo::ingredient::StaticIngredientRepo;
use crate::rest::types::{QueryParams, Url};
use crate::{domain, rest};

#[derive(Default, Debug)]
struct FetchIngredientsOpts<'a> {
    keys: Option<Vec<&'a str>>,
}

impl<'a> From<&QueryParams<'a>> for FetchIngredientsOpts<'a> {
    fn from(params: &QueryParams<'a>) -> Self {
        params
            .iter()
            .fold(FetchIngredientsOpts::default(), |mut opts, p| {
                match p {
                    ("key", val) => {
                        let mut keys = opts.keys.unwrap_or_default();
                        keys.push(val);
                        opts.keys = Some(keys)
                    }
                    _ => {}
                };

                opts
            })
    }
}

impl From<FetchIngredientsOpts<'_>> for domain::ingredient::fetch_list::RequestOpts {
    fn from(rest: FetchIngredientsOpts) -> Self {
        let keys = rest
            .keys
            .map(|keys| keys.into_iter().map(String::from).collect());
        Self { keys }
    }
}

pub fn fetch_list(rest_ctx: &rest::Context, url: &Url) -> Response<Cursor<Vec<u8>>> {
    use domain::ingredient::fetch_list;
    let opts = FetchIngredientsOpts::from(url.query_params());

    let ctx = rest_ctx.clone().into();

    let repo = StaticIngredientRepo;
    let ingredients = fetch_list::execute(&repo, &ctx, opts.into())
        .into_iter()
        .map(rest::Ingredient::from)
        .collect::<Vec<_>>();
    let data = serde_json::to_string(&ingredients).unwrap();

    Response::from_string(data)
        .with_header(Header::from_str("content-type: application/json").unwrap())
}

pub fn fetch_by_key(rest_ctx: &rest::Context, _url: &Url, key: &str) -> Response<Cursor<Vec<u8>>> {
    use domain::ingredient::fetch_by_key;
    let repo = StaticIngredientRepo;

    let ctx = rest_ctx.clone().into();

    // TODO: catch notfound error
    let ingredient = fetch_by_key::execute(&repo, &ctx, key.to_string())
        .ok()
        .map(rest::Ingredient::from);
    let data = serde_json::to_string(&ingredient).unwrap();

    Response::from_string(data)
        .with_header(Header::from_str("content-type: application/json").unwrap())
}