'use strict';

const conf = require('>/conf');

// Resolution rank so we can compare "what you own" against a candidate release.
function rankFromWidth(w){
	w = Number(w) || 0;
	if(w >= 3000) return 4; // 4k
	if(w >= 1700) return 3; // 1080p
	if(w >= 1000) return 2; // 720p
	if(w > 0) return 1;     // sd
	return 0;
}

function rankFromLabel(label){
	label = String(label || '').toLowerCase();
	if(/2160|4k|uhd/.test(label)) return 4;
	if(label.includes('1080')) return 3;
	if(label.includes('720')) return 2;
	if(label.includes('480')) return 1;
	return 0;
}

function labelFromRank(rank){ return ['', '480p', '720p', '1080p', '4k'][rank] || ''; }

async function embyGet(pathAndQuery){
	let sep = pathAndQuery.includes('?') ? '&' : '?';
	let res = await fetch(`${conf.emby.url}${pathAndQuery}${sep}api_key=${conf.emby.apiKey}`);
	if(!res.ok) throw new Error(`Emby ${res.status}`);
	return await res.json();
}

// Is this movie already in the library, and at what best quality? Never throws — an
// unreachable Emby just means "unknown", so search still works.
async function movieInLibrary(tmdbId){
	try{
		let data = await embyGet(`/Items?Recursive=true&IncludeItemTypes=Movie&AnyProviderIdEquals=tmdb.${tmdbId}&Fields=Width`);
		let items = data.Items || [];
		if(!items.length) return { owned: false, rank: 0, quality: '' };
		let rank = Math.max(...items.map(i => rankFromWidth(i.Width)));
		return { owned: true, rank, quality: labelFromRank(rank), count: items.length };
	}catch(error){
		return { owned: false, rank: 0, quality: '', unknown: true };
	}
}

// Which episodes of a series are already present, grouped by season( season -> count).
async function seriesInventory(tmdbId){
	try{
		let s = await embyGet(`/Items?Recursive=true&IncludeItemTypes=Series&AnyProviderIdEquals=tmdb.${tmdbId}&Fields=ProviderIds`);
		let series = (s.Items || [])[0];
		if(!series) return { owned: false, have: {} };

		let ep = await embyGet(`/Shows/${series.Id}/Episodes`);
		let sets = {};
		for(let e of ep.Items || []){
			let sn = e.ParentIndexNumber, en = e.IndexNumber;
			if(sn == null || en == null || sn === 0) continue; // skip specials
			(sets[sn] = sets[sn] || new Set()).add(en);
		}
		let have = {};
		for(let sn of Object.keys(sets)) have[sn] = sets[sn].size;
		return { owned: true, seriesId: series.Id, have };
	}catch(error){
		return { owned: false, have: {}, unknown: true };
	}
}

module.exports = { movieInLibrary, seriesInventory, rankFromWidth, rankFromLabel, labelFromRank };