(function () {
"use strict";

// as of 2018, LW does not use CDM, but leave it in just in case
const FACS = new Set(["AP", "ED", "ES", "FA", "GL", "GS", "HH", "LE", "LW", "SB", "SC"]);
const SUBJS = {
    "ACTG": ["SB"],
    "ADMB": ["AP"],
    "ADMS": ["AP"],
    "ANTH": ["AP", "GS"],
    "ARB":  ["AP"],
    "ARTH": ["FA", "GS"],
    "ARTM": ["SB"],
    "ASL":  ["AP"],
    "AUCO": ["ED"],
    "BBED": ["ED"],
    "BC":   ["SC"],
    "BCHM": ["SC"],
    "BIOL": ["SC", "GL", "GS", "ED"],
    "BLIS": ["GS"],
    "BPHS": ["SC"],
    "BSUS": ["SB"],
    "BUEC": ["GL"],
    "CAT":  ["GL"],
    "CCY":  ["AP"],
    "CDIS": ["GS"],
    "CDNS": ["AP", "GL"],
    "CGTA": ["GS"],
    "CH":   ["AP"],
    "CHEM": ["SC", "GS", "ED"],
    "CIVL": ["LE", "GS"],
    "CLST": ["AP"],
    "CLTR": ["AP"],
    "CMCT": ["GS"],
    "COGS": ["AP"],
    "COMN": ["AP"],
    "COMS": ["GL"],
    "COOP": ["LE", "SC"],
    "CRIM": ["AP"],
    "CSLA": ["GL"],
    "DANC": ["FA", "GS", "ED"],
    "DATT": ["FA"],
    "DCAD": ["SB"],
    "DEMS": ["AP", "GS"],
    "DESN": ["FA"],
    "DEST": ["ED"],
    "DIGM": ["GS"],
    "DLLL": ["AP"],
    "DRAA": ["ED"],
    "DRST": ["GL"],
    "DVST": ["GS"],
    "ECON": ["AP", "GL", "SB", "GS", "ED"],
    "EDFE": ["ED"],
    "EDFR": ["ED"],
    "EDIN": ["ED"],
    "EDIS": ["ED"],
    "EDJI": ["ED"],
    "EDPJ": ["ED"],
    "EDPR": ["ED"],
    "EDST": ["ED"],
    "EDUC": ["ED", "GS"],
    "EECS": ["LE", "GS"],
    "EIL":  ["GS"],
    "EMBA": ["SB"],
    "EN":   ["AP", "GL", "GS", "ED"],
    "ENG":  ["LE", "GS"],
    "ENSL": ["GL"],
    "ENTR": ["SB"],
    "ENVB": ["SC"],
    "ENVS": ["GS", "ED"],
    "ESL":  ["AP"],
    "ESS":  ["GS"],
    "ESSE": ["LE"],
    "EXCH": ["SB"],
    "FACC": ["GS"],
    "FACS": ["FA"],
    "FAST": ["ED"],
    "FILM": ["FA", "GS"],
    "FINE": ["SB"],
    "FND":  ["AP"],
    "FNEN": ["SB"],
    "FNSV": ["SB"],
    "FR":   ["AP"],
    "FRAN": ["GL"],
    "FREN": ["ED", "GS"],
    "FSL":  ["GL"],
    "GCIN": ["AP"],
    "GEOG": ["AP", "SC", "GS", "ED"],
    "GER":  ["AP"],
    "GFWS": ["GS"],
    "GK":   ["AP"],
    "GKM":  ["AP"],
    "GWST": ["AP", "GL"],
    "HEB":  ["AP", "ED"],
    "HIMP": ["SB"],
    "HIST": ["AP", "GL", "GS", "ED"],
    "HLST": ["HH"],
    "HLTH": ["GS"],
    "HREQ": ["AP"],
    "HRM":  ["AP", "GS"],
    "HUMA": ["AP", "GL", "GS"],
    "IBUS": ["SB"],
    "IHST": ["HH"],
    "ILST": ["GL"],
    "INDG": ["AP"],
    "INDS": ["ED"],
    "INDV": ["AP", "FA"],
    "INST": ["GS"],
    "INTE": ["GS"],
    "INTL": ["SB"],
    "ISCI": ["SC"],
    "IT":   ["AP"],
    "ITEC": ["AP", "GL", "GS"],
    "JC":   ["AP"],
    "JP":   ["AP"],
    "KAHS": ["GS"],
    "KINE": ["HH"],
    "KOR":  ["AP"],
    "LA":   ["AP"],
    "LAL":  ["GS"],
    "LASO": ["AP"],
    "LAW":  ["ED", "GS", "LW"],
    "LIN":  ["GL"],
    "LING": ["AP"],
    "LLDV": ["ED"],
    "LLS":  ["AP"],
    "LREL": ["GS"],
    "LYON": ["GL"],
    "MACC": ["SB"],
    "MATH": ["SC", "GL", "ED", "GS"],
    "MBA":  ["SB"],
    "MBAN": ["SB"],
    "MDES": ["GS"],
    "MECH": ["GS"],
    "MFIN": ["SB"],
    "MGMT": ["SB"],
    "MINE": ["SB"],
    "MIST": ["AP"],
    "MKTG": ["SB"],
    "MODR": ["AP", "GL"],
    "MSTM": ["SB"],
    "MUSI": ["FA", "GS", "ED"],
    "NATS": ["SC", "GL"],
    "NURS": ["HH", "GS"],
    "OMIS": ["SB"],
    "ORCO": ["ED"],
    "ORGS": ["SB"],
    "OVGS": ["SB", "GS"],
    "PACC": ["GS"],
    "PANF": ["FA"],
    "PERS": ["AP"],
    "PHED": ["ED"],
    "PHIL": ["AP", "GL", "GS", "ED"],
    "PHYS": ["SC", "GL", "GS", "ED"],
    "PIA":  ["GS"],
    "PKIN": ["HH"],
    "PLCY": ["SB"],
    "POLS": ["AP", "GL", "GS", "ED"],
    "POR":  ["AP"],
    "PPAL": ["GS"],
    "PPAS": ["AP"],
    "PRAC": ["ED"],
    "PROP": ["SB"],
    "PRWR": ["AP"],
    "PSYC": ["GS", "GL"],
    "PUBL": ["SB"],
    "RU":   ["AP"],
    "SCIE": ["ED"],
    "SENE": ["SC"],
    "SGMT": ["SB"],
    "SLGS": ["ED"],
    "SLST": ["GS"],
    "SOCI": ["AP", "GL", "GS"],
    "SOSC": ["AP", "GL", "ED"],
    "SOWK": ["AP", "GS"],
    "SP":   ["AP", "GL"],
    "SPTH": ["GS"],
    "STS":  ["GS"],
    "SWAH": ["AP"],
    "SXST": ["AP", "GL"],
    "TECH": ["ED"],
    "TESL": ["AP"],
    "THEA": ["FA", "GS"],
    "THST": ["GS"],
    "TLSE": ["ED"],
    "TRAN": ["GL", "GS"],
    "TRAS": ["GS"],
    "TXLW": ["GS"],
    "TYP":  ["AP"],
    "VISA": ["FA", "GS"],
    "WKLS": ["AP"]
}

const TOKEN_DELIM_RE = /[^A-Za-z0-9.=]/;
const CRSN_RE = /^[0-9]{4}$/;
const DEPTCRSN_RE = /^([A-Z]{2,4})([0-9]{4})$/;
const CRED_RE = /^(?:Cr=([0-9]{1,2}(?:\.[0-9]{0,2})?)|([0-9]{1,2}\.[0-9]{0,2}))$/;
const MAYBE_CRED_RE = /^[0-9]{1,2}$/;
const MAYBE_DEPT_RE = /^[A-Z]{2,4}$/;

function parse_ycq_s(str) {
    let ycq_s = JSON.parse(str || "{}");
    ycq_s.course_creds = ycq_s.course_creds || {};
    ycq_s.course_subjs = ycq_s.course_subjs || {};
    ycq_s.course_facs = ycq_s.course_facs || {};
    ycq_s.subj_facs = ycq_s.subj_facs || {};
    ycq_s.default_facs = ycq_s.default_facs || [];
    return ycq_s;
}
var cached_ycq_s = parse_ycq_s(localStorage.ycq);

let now = new Date();
let month = now.getMonth();
// change to next summer on new year
// begin next FW on July 1
let fw_year, s_year;
if (month >= 6) {
    fw_year = now.getFullYear();
} else {
    fw_year = now.getFullYear() - 1;
}
s_year = now.getFullYear();
let fw_sess = document.createElement("option");
let fw_sess_val = "FW " + fw_year;
fw_sess.value = fw_sess_val;
fw_sess.textContent = `Fall/Winter ${fw_year}-${fw_year+1}`;
let s_sess = document.createElement("option");
let s_sess_val = "SU " + (s_year - 1);
s_sess.value = s_sess_val;
s_sess.textContent = `Summer ${s_year}`;
switch (cached_ycq_s.sess) {
    case fw_sess_val: fw_sess.selected = true; break;
    case s_sess_val: s_sess.selected = true; break;
    default:
        /* assume enrolling for summer courses between March and May inclusive */
        if (month >= 2 && month <= 4)
            s_sess.selected = true;
        else
            fw_sess.selected = true;
}

let ENGLISH_TYPES = {
    "fac": "faculty",
    "subj": "subject",
    "crsn": "course number",
    "cred": "credit number"
};

function ready() {
    // when embedded in the webextension, the protocol will be moz-extension://
    // or chrome:// or something like that
    if (!/^(?:https?|file):$/.test(location.protocol)) {
        document.getElementById("ywh-ad").style.display = "none";
    }

    let sessions = document.getElementById("sessions");
    sessions.appendChild(fw_sess);
    sessions.appendChild(s_sess);

    let input = document.getElementById("input");
    let link = document.getElementById("link");
    let linkContainer = document.getElementById("link-container");

    let state;

    let add_li = function (l, t) {
        var e = document.createElement("li");
        e.innerHTML = t;
        l.appendChild(e);
    };

    let apply = function () {
        state = {subj: "", fac: "", crsn: "", cred: ""};
        let multiple = new Set();
        let curWarn = document.getElementById("warning-list");
        let warn = curWarn.cloneNode(false);
        let curError = document.getElementById("error-list");
        let error = curError.cloneNode(false);

        let got = function (type, token) {
            if (state[type])
                multiple.add(ENGLISH_TYPES[type]);
            state[type] = token;
        };

        let tryParse = function (token) {
            let subjcrsn, cred;
            if (SUBJS.hasOwnProperty(token)) {
                got("subj", token);
            } else if (FACS.has(token)) {
                got("fac", token);
            } else if ((subjcrsn = DEPTCRSN_RE.exec(token))) {
                got("subj", subjcrsn[1]);
                got("crsn", subjcrsn[2]);
            } else if ((cred = CRED_RE.exec(token))) {
                got("cred", parseFloat(cred[1] || cred[2]).toFixed(2));
            } else if (CRSN_RE.test(token)) {
                got("crsn", token);
            } else if (MAYBE_CRED_RE.test(token)) {
                got("cred", parseFloat(token).toFixed(2));
                add_li(warn, `assuming ${token} is the number of credits`);
            } else if (MAYBE_DEPT_RE.test(token)) {
                state["maybeSubj"] = token;
            } else {
                return false;
            }
            return true;
        };

        let unk_tokens = [];
        input.value.split(TOKEN_DELIM_RE).forEach(function (token) {
            if (!token || tryParse(token) || tryParse(token.toUpperCase()))
                return;
            unk_tokens.push(token);
        });

        if (!state["subj"] && state["maybeSubj"]) {
            state["subj"] = state["maybeSubj"];
            add_li(warn, `guessing subject is "${state["maybeSubj"]}".`);
        }

        if (!state["subj"] && state["crsn"] && cached_ycq_s.course_subjs[state["crsn"]]) {
            state["subj"] = cached_ycq_s.course_subjs[state["crsn"]];
            add_li(warn, `assuming ${state["crsn"]} means ${state["subj"]} ${state["crsn"]}, because you last used ${state["subj"]} for ${state["crsn"]}.`);
        }

        if (!state["subj"] && cached_ycq_s.default_subj) {
            state["subj"] = cached_ycq_s.default_subj;
            add_li(warn, `using ${state["subj"]}, because that was your most recently queried subject.`);
        }

        if (!state["fac"] && state["subj"]) {
            // if no faculty, try:
            // 1. most recent faculty for this course
            // 2. most recent faculty for this subject
            // 3. most recent compatible faculty
            // 4. first compatible faculty
            let compat_facs = SUBJS[state["subj"]];

            // needs to be a function so it can remove the current selection
            let other_options = function () {
                if (compat_facs) {
                    let other_facs = compat_facs
                        .filter(f => f != state["fac"])
                        .map(f => `<a href="#" class="prepend-query" data-query="${f}">${f}/${state["subj"]}</a>`)
                        .join(", ");
                    if (other_facs.length)
                        return "other options: " + other_facs;
                }
                return "";
            }

            // 1. most recent faculty for this course
            if (state["crsn"] && cached_ycq_s.course_facs[state["subj"] + state["crsn"]]) {
                state["fac"] = cached_ycq_s.course_facs[state["subj"] + state["crsn"]];
                add_li(warn, `assuming ${state["subj"]} ${state["crsn"]} is ${state["fac"]}/${state["subj"]} because you last used ${state["fac"]} for ${state["subj"]} ${state["crsn"]}. ${other_options()}`);
            } else if (cached_ycq_s.subj_facs[state["subj"]]) {
                // 2. most recent faculty for this subject
                state["fac"] = cached_ycq_s.subj_facs[state["subj"]];
                add_li(warn, `assuming ${state["subj"]} means ${state["fac"]}/${state["subj"]} because you last used ${state["fac"]} for ${state["subj"]}. ${other_options()}`);
            } else if (compat_facs) {
                // 3. most recent compatible faculty
                if (cached_ycq_s.default_facs)
                    for (let i = cached_ycq_s.default_facs.length - 1; i >= 0; i--)
                        if (compat_facs.indexOf(cached_ycq_s.default_facs[i]) > -1)
                            state["fac"] = cached_ycq_s.default_facs[i];

                if (state["fac"]) {
                    add_li(warn, `assuming ${state["subj"]} means ${state["fac"]}/${state["subj"]} because you recently used ${state["fac"]}. ${other_options()}`);
                } else {
                    // 4. first compatible faculty
                    state["fac"] = compat_facs[0];
                    if (compat_facs.length > 1)
                        add_li(warn, `assuming ${state["subj"]} means ${state["fac"]}/${state["subj"]}. ${other_options()}`);
                    else
                        add_li(warn, `assuming ${state["subj"]} means ${state["fac"]}/${state["subj"]}`);
                }
            } else {
                add_li(error, "no faculty provided and unknown subject");
            }
        }

        if (state["subj"] && state["crsn"] && !state["cred"]) {
            if (cached_ycq_s.course_creds[state["subj"] + state["crsn"]]) {
                state["cred"] = cached_ycq_s.course_creds[state["subj"] + state["crsn"]];
                add_li(warn, `assuming ${state["subj"]} ${state["crsn"]} is ${state["cred"]} credits, because you last used ${state["cred"]} for ${state["subj"]} ${state["crsn"]}.`);
            } else {
                state["cred"] = "3.00";
                add_li(warn, "assuming the number of credits is 3.00, because that's the most common number.");
            }
        }

        let sess = document.getElementById("sessions").value.split(" ");
        state["sess"] = sess[0];
        state["year"] = parseInt(sess[1], 10);

        if (state["fac"] && state["subj"] && state["crsn"] && state["cred"] && state["year"] && state["sess"]) {
            link.href = `https://w2prod.sis.yorku.ca/Apps/WebObjects/cdm.woa/wa/crsq?fa=${state["fac"]}&sj=${state["subj"]}&cn=${state["crsn"]}&cr=${state["cred"]}&ay=${state["year"]}&ss=${state["sess"]}`;
            link.textContent = `${state["fac"]}/${state["subj"]} ${state["crsn"]} ${state["cred"]} (${sessions.selectedOptions[0].textContent}) | York University`;
            linkContainer.style.display = "block";
        } else if (state["fac"] && state["subj"] && state["sess"]) {
            link.href = `https://w2prod.sis.yorku.ca/Apps/WebObjects/cdm.woa/wa/crsq1?faculty=${state["fac"]}&subject=${state["subj"]}&academicyear=${state["year"]}&studysession=${state["sess"]}`;
            link.textContent = `${state["fac"]}/${state["subj"]} Courses (${sessions.selectedOptions[0].textContent}) | York University`;
            linkContainer.style.display = "block";
        } else {
            linkContainer.style.display = "none";
            add_li(error, "need at least subject. see examples above");
        }

        if (multiple.size)
            add_li(warn, "multiple terms for " + Array.from(multiple.values()).join(", ") + ", using last occurrence for each");

        curWarn.parentNode.replaceChild(warn, curWarn);
        curError.parentNode.replaceChild(error, curError);
        document.getElementById("warning").style.display = warn.children.length ? "block" : "none";
        document.getElementById("error").style.display = error.children.length ? "block" : "none";
    };
    input.addEventListener("input", apply);
    sessions.addEventListener("change", apply);

    document.body.addEventListener("click", function (e) {
        if (e.target.closest(".sample-query")) {
            e.preventDefault();
            input.select();
            // doesn't work in Firefox, oh well
            if (!document.execCommand || !document.execCommand("insertText", false, e.target.textContent))
                input.value = e.target.textContent;
            apply();
            input.focus();
        } else if (e.target.closest(".prepend-query")) {
            e.preventDefault();
            let r = false;
            let t = e.target.hasAttribute("data-query") ? e.target.getAttribute("data-query") : e.target.textContent;
            if (document.execCommand) {
                input.setSelectionRange(0, 0);
                r = document.execCommand("insertText", false, t + " ");
            }
            if (!r)
                input.value = t + " " + input.value;
            apply();
        }
    });

    let save_defaults = function () {
        let old_ycq_s_s = localStorage.ycq;
        let new_ycq_s = parse_ycq_s(old_ycq_s_s);

        if (state["fac"]) {
            let default_facs = new Set(new_ycq_s.default_facs);
            default_facs.delete(state["fac"]);
            default_facs.add(state["fac"]);
            let new_facs = Array.from(default_facs);
            if (new_facs.length != new_ycq_s.default_facs.length ||
                new_facs.some((v, i) => v !== new_ycq_s.default_facs[i])) {
                new_ycq_s.default_facs = new_facs;
            }
        }

        if (state["subj"]) {
            if (state["fac"]) {
                if (state["crsn"])
                    new_ycq_s.course_facs[state["subj"] + state["crsn"]] = state["fac"];
                new_ycq_s.subj_facs[state["subj"]] = state["fac"];
            }
            if (state["crsn"]) {
                if (state["cred"])
                    new_ycq_s.course_creds[state["subj"] + state["crsn"]] = state["cred"];
                new_ycq_s.course_subjs[state["crsn"]] = state["subj"];
            }
            new_ycq_s.default_subj = state["subj"];
        }

        new_ycq_s.sess = document.getElementById("sessions").value;

        let new_ycq_s_s = JSON.stringify(new_ycq_s);
        if (new_ycq_s_s != old_ycq_s_s) {
            cached_ycq_s = new_ycq_s;
            localStorage.ycq = new_ycq_s_s;
        }
    };
    link.addEventListener("click", save_defaults);
    document.forms[0].addEventListener("submit", function (e) {
        e.preventDefault();
        if (linkContainer.style.display == "block")
            link.click();
    });
    input.addEventListener("keydown", function (e) {
        if (e.key == "Enter") {
            e.preventDefault();
            if (linkContainer.style.display == "block") {
                // firefox silently ignores simulated link events with keyboard modifiers
                // this way triggers popup blocker but nothing we can do about it
                if (navigator.userAgent.indexOf("Firefox/") > -1 && (e.ctrlKey || e.shiftKey || e.altKey || e.metaKey)) {
                    if (e.ctrlKey) {
                        link.target = "_blank";
                        link.click();
                        link.target = "";
                    } else if (e.shiftKey) {
                        // note: other methods save by link click listener
                        // for efficiency, don't save twice
                        save_defaults();
                        window.open(link.href, "_blank", "noopener,width=625,resizable,menubar,toolbar,location,personalbar,status,scrollbars");
                    } else { // dunno what to do
                        link.click();
                    }
                } else {
                    link.dispatchEvent(new MouseEvent("click", e));
                }
            }
        }
    });
    apply();
}

if (document.readyState === "interactive" || document.readyState === "complete") {
    ready();
} else {
    document.addEventListener("DOMContentLoaded", ready);
}
}());