// ==UserScript==
// @name        RedHat jira BZ Linker
// @version     0.0.1
// @namespace   https://git.sagidayan.com/sagi/greasemonkey-scripts
// @author      Sagi Dayan
// @description Adds BZ links in (RedHat) Jira when needed
// @match       https://issues.redhat.com/*
// ==/UserScript==

(function () {
    // Constants
    const LOG_TAG = '[BZ-LINKER]';
    const summaryRegExp = new RegExp(/\[([0-9]+)\]/);

    // Entry point - observe DOM changes - and search for unlinked jira tickets
    var observer = new MutationObserver(update);
    observer.observe(document.body, { childList: true, characterData: true, subtree: true });

    // adds a tag prefix to logs for easy filters
    function log(...args) {
        const msg = args.reduce((msg, data) => {
            return `${msg} ${data}`;
        }, LOG_TAG);
        console.log(msg);
    }

    // When DOM changes - check for new unlinked issues
    function update() {
        const issues = filterAndInflate([...document.getElementsByClassName("issuerow")]);
        if (issues.length) log(`Found #${issues.length} new unlinked issues. Linking...`);
        issues.forEach(issue => {
            const issueId = issue.bzId;
            if (issueId) {
                const link = document.createElement('a');
                const p = document.createElement('p');
                link.href = `https://bugzilla.redhat.com/show_bug.cgi?id=${issueId}`;
                link.classList = ['issue-link'];
                link.target = '_blank';
                link.innerHTML = `🐞 Bugzilla Bug: ${issueId} 🐞`;
                p.style = 'margin-top:10px;';
                p.append(link);
                issue.summaryElm.append(p);
            }
            issue.touched = true;
        });
    }
    // Returns only rows (TR tags) that are not linked and are BZ bugs
    function filterAndInflate(rows) {
        return rows.filter(r => {
            if (r.tagName === 'TR' && !r.touched) {
                const summary = [...r.children].reduce((prev, child) => {
                    if (prev) return prev;
                    if (child.getAttribute('data-field-id') === 'summary'
                        || child.className.indexOf('summary') != -1) {
                        r.summaryElm = child;
                        return child.innerHTML;
                    }
                }, null)
                if (!summary) return false;
                const bzId = summary.match(summaryRegExp);
                if (bzId) {
                    r.bzId = bzId[1];
                    return true;
                }
            }
            return false;
        })
    }
})();