import { createClient } from "@libsql/client/web";
import { mkdir, writeFile } from "node:fs/promises";
import { dirname, resolve } from "node:path";
import {
  ensureAnalyticsSchema,
  getWeeklyReport,
  renderWeeklyMarkdown,
  type Connections
} from "~/server/weekly-metrics";

/**
 * Write `marketing/metrics/weekly.md` from the live analytics and licence DBs.
 *
 *   bun --env-file=.env scripts/weekly-metrics.ts
 *   bun --env-file=.env scripts/weekly-metrics.ts --days 14 --now 2026-11-05T09:00:00Z
 *
 * Required environment (all four; the analytics token also opens the licence
 * DB, which is why the weekly job can run from a checkout that has no Stripe
 * or Apple secrets):
 *
 *   TURSO_DB_URL / TURSO_DB_TOKEN        freno.me DB — VisitorAnalytics
 *   NOOK_DB_URL / NOOK_DB_TOKEN          the-nook DB — trials, licenses, activations
 *
 * This script deliberately does not import `~/env/server`: that schema demands
 * every production secret, and the metrics job needs two databases and nothing
 * else.
 *
 * The output path is anchored at the repo root, so running it from any cwd
 * writes the same file.
 */

interface Options {
  days: number;
  now: Date;
  out: string;
  stdout: boolean;
}

function usage(): string {
  return [
    "Usage: bun --env-file=.env scripts/weekly-metrics.ts [options]",
    "",
    "  --days N          window length in days (default 7)",
    "  --now ISO         end of the window (default: now)",
    "  --out PATH        where to write (default: marketing/metrics/weekly.md)",
    "  --stdout          print the report instead of writing a file"
  ].join("\n");
}

function parseArgs(argv: string[]): Options {
  const repoRoot = resolve(import.meta.dir, "..");
  const options: Options = {
    days: 7,
    now: new Date(),
    out: resolve(repoRoot, "marketing/metrics/weekly.md"),
    stdout: false
  };

  for (let i = 0; i < argv.length; i += 1) {
    const arg = argv[i]!;
    const value = () => {
      const next = argv[i + 1];
      if (next === undefined) throw new Error(`${arg} needs a value\n\n${usage()}`);
      i += 1;
      return next;
    };

    switch (arg) {
      case "--days": {
        const days = Number(value());
        if (!Number.isFinite(days) || days <= 0) {
          throw new Error(`--days must be a positive number\n\n${usage()}`);
        }
        options.days = days;
        break;
      }
      case "--now": {
        const now = new Date(value());
        if (Number.isNaN(now.getTime())) {
          throw new Error(`--now must be an ISO timestamp\n\n${usage()}`);
        }
        options.now = now;
        break;
      }
      case "--out":
        options.out = resolve(value());
        break;
      case "--stdout":
        options.stdout = true;
        break;
      case "-h":
      case "--help":
        console.log(usage());
        process.exit(0);
      default:
        throw new Error(`Unknown argument ${arg}\n\n${usage()}`);
    }
  }

  return options;
}

function requiredEnv(name: string): string {
  const value = process.env[name];
  if (!value || value.trim() === "") {
    throw new Error(
      `${name} is not set. The weekly job needs TURSO_DB_URL, TURSO_DB_TOKEN, ` +
        `NOOK_DB_URL and NOOK_DB_TOKEN — run it as ` +
        `\`bun --env-file=.env scripts/weekly-metrics.ts\` with those four in .env.`
    );
  }
  return value;
}

function connect(url: string, token: string) {
  return createClient({ url, authToken: token });
}

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

  const connections: Connections = {
    analytics: connect(requiredEnv("TURSO_DB_URL"), requiredEnv("TURSO_DB_TOKEN")),
    nook: connect(requiredEnv("NOOK_DB_URL"), requiredEnv("NOOK_DB_TOKEN"))
  };

  // The app migrates the table on boot, but this job must not depend on a
  // deploy having happened: add any missing post-hoc columns (stage, host)
  // through the same idempotent bootstrap path first.
  await ensureAnalyticsSchema(connections.analytics);

  const report = await getWeeklyReport(connections, {
    days: options.days,
    now: options.now
  });
  const markdown = renderWeeklyMarkdown(report);

  if (options.stdout) {
    process.stdout.write(markdown);
    return;
  }

  await mkdir(dirname(options.out), { recursive: true });
  await writeFile(options.out, markdown, "utf8");

  const f = report.counts;
  console.log(
    `wrote ${options.out}\n` +
      `window ${report.window.start} → ${report.window.end}\n` +
      `visit ${f.visit}, download click ${f.downloadClick}, DMG served ${f.dmgServed}, ` +
      `trial ${f.trial}, checkout ${f.checkout}, purchase ${f.purchase}, activation ${f.activation}\n` +
      `mover: ${report.mover ? `${report.mover.label} ${report.mover.before} → ${report.mover.now}` : "none"}`
  );
}

main().catch((error) => {
  console.error(error instanceof Error ? error.message : error);
  process.exit(1);
});