/**
 * Myext querying page settings with regard to wildcard records
 *
 * Copyright (C) 2021 Wojtek Kosior
 * Redistribution terms are gathered in the `copyright' file.
 */

/*
 * IMPORTS_START
 * IMPORT make_once
 * IMPORT get_storage
 * IMPORT TYPE_PREFIX
 * IMPORTS_END
 */

var storage;

var exports = {};

async function init(fun)
{
    storage = await get_storage();

    return fun;
}

// TODO: also support urls with specified ports
function query(url, multiple)
{
    let proto_re = "[a-zA-Z]*:\/\/";
    let domain_re = "[^/?#]+";
    let segments_re = "/[^?#]*";
    let query_re = "\\?[^#]*";

    let url_regex = new RegExp(`\
^\
(${proto_re})\
(${domain_re})\
(${segments_re})?\
(${query_re})?\
#?.*\$\
`);

    let regex_match = url_regex.exec(url);
    if (regex_match === null) {
	console.log("bad url format", url);
	return multiple ? [] : [undefined, undefined];
    }

    let [_, proto, domain, segments, query] = regex_match;

    domain = domain.split(".");
    let segments_trailing_dash =
	segments && segments[segments.length - 1] === "/";
    segments = (segments || "").split("/").filter(s => s !== "");
    segments.unshift("");

    let matched = [];

    for (let d_slice = 0; d_slice < domain.length; d_slice++) {
	let domain_part = domain.slice(d_slice).join(".");
	let domain_wildcards = [];
	if (d_slice === 0)
	    domain_wildcards.push("");
	if (d_slice === 1)
	    domain_wildcards.push("*.");
	if (d_slice > 0)
	    domain_wildcards.push("**.");
	domain_wildcards.push("***.");

	for (let domain_wildcard of domain_wildcards) {
	    let domain_pattern = domain_wildcard + domain_part;

	    for (let s_slice = segments.length; s_slice > 0; s_slice--) {
		let segments_part = segments.slice(0, s_slice).join("/");
		let segments_wildcards = [];
		if (s_slice === segments.length) {
		    if (segments_trailing_dash)
			segments_wildcards.push("/");
		    segments_wildcards.push("");
		}
		if (s_slice === segments.length - 1) {
		    if (segments[s_slice] !== "*")
			segments_wildcards.push("/*");
		}
		if (s_slice < segments.length &&
		    (segments[s_slice] !== "**" ||
		     s_slice < segments.length - 1))
		    segments_wildcards.push("/**");
		if (segments[s_slice] !== "***" ||
		    s_slice < segments.length)
		    segments_wildcards.push("/***");

		for (let segments_wildcard of segments_wildcards) {
		    let segments_pattern =
			segments_part + segments_wildcard;

		    let pattern = proto + domain_pattern + segments_pattern;
		    console.log("trying", pattern);
		    let settings = storage.get(TYPE_PREFIX.PAGE, pattern);

		    if (settings === undefined)
			continue;

		    if (!multiple)
			return [pattern, settings];

		    matched.push([pattern, settings]);
		}
	    }
	}
    }

    return multiple ?  matched : [undefined, undefined];
}

function query_best(url)
{
    return query(url, false);
}

function query_all(url)
{
    return query(url, true);
}

const get_query_best = make_once(() => init(query_best));
const get_query_all = make_once(() => init(query_all));

/*
 * EXPORTS_START
 * EXPORT get_query_best
 * EXPORT get_query_all
 * EXPORTS_END
 */