#!/usr/bin/env node
// scripts/webex-rooms-report.ts
//
// READ-ONLY diagnostic. Lists every Webex room the bot token can see, buckets
// them by last-activity age, and cross-references against legacy/spaces.json
// so we can tell sendi-managed rooms apart from any others.
//
// Nothing is written. No DELETE calls are issued. Safe to run at any time.
//
// Usage:
//   npm run webex-rooms-report              # full report
//   npm run webex-rooms-report -- --months=24  # highlight rooms stale > N months
//   npm run webex-rooms-report -- --stale-only # print details only for stale rooms

import fs from 'fs';
import path from 'path';
import env from '../src/config/env.ts';

interface WebexRoom {
    id: string;
    title: string;
    type: 'group' | 'direct';
    isLocked?: boolean;
    lastActivity?: string;
    created?: string;
}

interface Args {
    months: number;
    staleOnly: boolean;
    sampleSize: number;
}

function parseArgs(argv: string[]): Args {
    const a: Args = { months: 24, staleOnly: false, sampleSize: 20 };
    for (const raw of argv) {
        if (raw === '--stale-only') { a.staleOnly = true; continue; }
        const m = /^--months=(\d+)$/.exec(raw);
        if (m) { a.months = parseInt(m[1]!, 10); continue; }
        const s = /^--sample=(\d+)$/.exec(raw);
        if (s) { a.sampleSize = parseInt(s[1]!, 10); continue; }
    }
    return a;
}

function parseLinkHeader(link: string | null): string | undefined {
    if (!link) return undefined;
    // Format: <https://webexapis.com/v1/rooms?...>; rel="next"
    const match = /<([^>]+)>;\s*rel="next"/i.exec(link);
    return match?.[1];
}

async function fetchAllRooms(): Promise<WebexRoom[]> {
    const rooms: WebexRoom[] = [];
    let next: string | undefined = `https://webexapis.com/v1/rooms?max=1000&sortBy=lastactivity`;
    let pageCount = 0;
    while (next) {
        pageCount++;
        process.stdout.write(`  fetching page ${pageCount}...\r`);
        const res = await fetch(next, {
            headers: { Authorization: `Bearer ${env.WEBEX_TOKEN}` },
        });
        if (!res.ok) {
            const body = await res.text().catch(() => '');
            throw new Error(`Webex list rooms failed (${res.status}): ${body.slice(0, 300)}`);
        }
        const json = (await res.json()) as { items: WebexRoom[] };
        rooms.push(...(json.items ?? []));
        next = parseLinkHeader(res.headers.get('link'));
    }
    process.stdout.write('\n');
    return rooms;
}

function loadLegacySpaceIds(): Set<string> {
    const jsonPath = path.resolve(process.cwd(), 'legacy', 'spaces.json');
    if (!fs.existsSync(jsonPath)) return new Set();
    const data = JSON.parse(fs.readFileSync(jsonPath, 'utf8')) as Record<string, unknown>;
    return new Set(Object.keys(data));
}

function ageInDays(d: Date, now: Date = new Date()): number {
    return Math.floor((now.getTime() - d.getTime()) / (24 * 60 * 60 * 1000));
}

async function main(): Promise<void> {
    const args = parseArgs(process.argv.slice(2));

    console.log('Fetching all Webex rooms the bot can see (paginated)...');
    const rooms = await fetchAllRooms();
    console.log(`  → ${rooms.length} rooms total\n`);

    const legacyIds = loadLegacySpaceIds();
    console.log(`Legacy spaces.json known IDs: ${legacyIds.size}\n`);

    // ---- Bucket rooms by lastActivity age ----
    const now = new Date();
    const buckets: Record<string, WebexRoom[]> = {
        'no lastActivity': [],
        '≤ 7 days': [],
        '≤ 30 days': [],
        '≤ 3 months': [],
        '≤ 6 months': [],
        '≤ 12 months': [],
        '≤ 18 months': [],
        '≤ 24 months': [],
        '> 24 months': [],
    };
    for (const r of rooms) {
        if (!r.lastActivity) { buckets['no lastActivity']!.push(r); continue; }
        const days = ageInDays(new Date(r.lastActivity), now);
        if (days <= 7) buckets['≤ 7 days']!.push(r);
        else if (days <= 30) buckets['≤ 30 days']!.push(r);
        else if (days <= 90) buckets['≤ 3 months']!.push(r);
        else if (days <= 180) buckets['≤ 6 months']!.push(r);
        else if (days <= 365) buckets['≤ 12 months']!.push(r);
        else if (days <= 547) buckets['≤ 18 months']!.push(r);
        else if (days <= 730) buckets['≤ 24 months']!.push(r);
        else buckets['> 24 months']!.push(r);
    }

    console.log('Activity buckets (all rooms bot can see):');
    for (const [name, arr] of Object.entries(buckets)) {
        const inLegacy = arr.filter((r) => legacyIds.has(r.id)).length;
        console.log(`  ${name.padEnd(18)}  count=${String(arr.length).padStart(5)}   in legacy=${inLegacy}`);
    }

    // ---- Rooms stale beyond the threshold ----
    const cutoffMs = now.getTime() - args.months * 30.4375 * 24 * 60 * 60 * 1000;
    const stale = rooms.filter((r) => {
        if (!r.lastActivity) return true;
        return new Date(r.lastActivity).getTime() < cutoffMs;
    });
    const staleInLegacy = stale.filter((r) => legacyIds.has(r.id));
    const staleNotInLegacy = stale.filter((r) => !legacyIds.has(r.id));

    console.log(`\nStale > ${args.months} months: ${stale.length}`);
    console.log(`  - in legacy spaces.json:      ${staleInLegacy.length}`);
    console.log(`  - NOT in legacy spaces.json:  ${staleNotInLegacy.length}`);

    // ---- Sanity: how many legacy rooms did we NOT see? (bot no longer a member) ----
    const seenIds = new Set(rooms.map((r) => r.id));
    let legacyMissing = 0;
    for (const id of legacyIds) if (!seenIds.has(id)) legacyMissing++;
    console.log(`\nLegacy spaces already gone from Webex (or bot removed): ${legacyMissing}`);

    // ---- Optional sample listing ----
    if (args.staleOnly || args.sampleSize > 0) {
        const sampleList = args.staleOnly ? staleInLegacy : rooms.slice(0, args.sampleSize);
        const label = args.staleOnly
            ? `\nSample of stale + legacy rooms (up to ${args.sampleSize}):`
            : `\nSample of first ${args.sampleSize} rooms (all):`;
        console.log(label);
        const header = 'lastActivity'.padEnd(22) + 'age(d) '.padStart(8) + '  ' + 'legacy? '.padEnd(9) + 'title';
        console.log(header);
        console.log('-'.repeat(header.length));
        for (const r of sampleList.slice(0, args.sampleSize)) {
            const la = r.lastActivity ?? '(none)';
            const days = r.lastActivity ? String(ageInDays(new Date(r.lastActivity), now)) : '  n/a';
            const isLegacy = legacyIds.has(r.id) ? 'yes' : 'no';
            console.log(`${la.padEnd(22)}${days.padStart(6)}    ${isLegacy.padEnd(9)}${r.title}`);
        }
    }

    console.log('\nDone. No changes made.');
}

main().catch((err) => {
    console.error(`\nReport failed: ${err instanceof Error ? err.message : String(err)}`);
    process.exit(1);
});