/**
 * Repair: re-seed AFL Wildcard winners into the Elimination Finals they belong in.
 *
 * Brackets advanced before the re-seeding fix crossed each Wildcard winner into a fixed
 * Elimination Final — the 7v10 winner always met 6th and the 8v9 winner always met 5th —
 * instead of pairing them by ladder position (5th hosts the lower-ranked winner). The
 * fix only changes how new results advance, so an already-advanced bracket keeps its
 * wrong pairings until this runs. The admin UI cannot re-trigger it: a completed match
 * renders as "Complete", with no way to re-submit the winner.
 *
 * This runs the same reseedAflEliminationFinals the advancement path now uses, so it
 * makes exactly the correction a fresh bracket would have. It only ever moves Wildcard
 * teams between the two Elimination Final slots — no results, scores or placements are
 * touched, and nothing else in the bracket is written. A bracket that is already correct
 * is left alone.
 *
 * If an Elimination Final has already been played, its qualifier cannot be moved without
 * rewriting who contested a recorded result; the script reports that event and skips it.
 * Clear and regenerate that bracket in Admin instead, then Reprocess Bracket.
 *
 * Safe to re-run. Validate on a DB snapshot first. Reads DATABASE_URL.
 *
 *   npx tsx scripts/fix-afl-wildcard-reseed.ts               # apply to every afl_10 event
 *   npx tsx scripts/fix-afl-wildcard-reseed.ts --dry         # report only
 *   npx tsx scripts/fix-afl-wildcard-reseed.ts --event <id>  # one event
 */

import { drizzle } from "drizzle-orm/postgres-js";
import postgres from "postgres";
import { eq } from "drizzle-orm";
import * as schema from "../database/schema.js";
import { DatabaseContext, database } from "../database/context.js";
import {
  findPlayoffMatchesByEventIdAndRound,
  reseedAflEliminationFinals,
} from "../app/models/playoff-match.js";
import { findParticipantsBySportsSeasonId } from "../app/models/season-participant.js";

const DRY = process.argv.includes("--dry");
const eventFlag = process.argv.indexOf("--event");
const ONLY_EVENT = eventFlag === -1 ? null : process.argv[eventFlag + 1];
const log = (...a: unknown[]) => console.log(...a);

async function run() {
  const db = database();

  const events = await db.query.scoringEvents.findMany({
    where: eq(schema.scoringEvents.bracketTemplateId, "afl_10"),
  });
  const targets = ONLY_EVENT ? events.filter((e) => e.id === ONLY_EVENT) : events;

  if (ONLY_EVENT && targets.length === 0) {
    log(`No afl_10 event with id ${ONLY_EVENT}.`);
    return;
  }
  log(`afl_10 events to check: ${targets.length}`);

  let fixed = 0;
  let alreadyRight = 0;
  let skipped = 0;

  for (const event of targets) {
    const name = event.name ?? event.id;

    const participants = await findParticipantsBySportsSeasonId(event.sportsSeasonId);
    const nameOf = (id: string | null) =>
      id === null ? "TBD" : participants.find((p) => p.id === id)?.name ?? id;

    /** "M1: <host> vs <qualifier>" for both Elimination Finals. */
    const pairings = async () => {
      const efMatches = await findPlayoffMatchesByEventIdAndRound(event.id, "Elimination Finals");
      return efMatches
        .toSorted((a, b) => a.matchNumber - b.matchNumber)
        .map((m) => `M${m.matchNumber}: ${nameOf(m.participant1Id)} vs ${nameOf(m.participant2Id)}`)
        .join(", ");
    };

    try {
      const before = await pairings();

      // The dry run still resolves the pairings — it just reports them instead of writing.
      if (DRY) {
        const efMatches = await findPlayoffMatchesByEventIdAndRound(event.id, "Elimination Finals");
        const wcMatches = await findPlayoffMatchesByEventIdAndRound(event.id, "Wildcard Round");
        const decided = wcMatches.filter((m) => m.isComplete && m.winnerId).length;
        log(`  ${name}: ${before} (${decided}/${wcMatches.length} Wildcard results, ` +
            `${efMatches.filter((m) => m.isComplete).length} Elimination Final(s) played)`);
        continue;
      }

      const reseed = await reseedAflEliminationFinals(event.id);
      if (reseed.vacated.length === 0 && reseed.filled.length === 0) {
        alreadyRight += 1;
        log(`  = ${name}: already correct — ${before}`);
        continue;
      }

      fixed += 1;
      log(`  ~ ${name}:`);
      log(`      was: ${before}`);
      log(`      now: ${await pairings()}`);
    } catch (e) {
      skipped += 1;
      log(`  ! ${name}: ${(e as Error).message}`);
    }
  }

  if (DRY) {
    log("\nDry run — no writes. Re-run without --dry to apply.");
    return;
  }
  log(`\nDone. re-seeded=${fixed}, already correct=${alreadyRight}, skipped=${skipped}.`);
}

async function main() {
  const dbUrl = process.env.DATABASE_URL;
  if (!dbUrl) {
    console.error("ERROR: DATABASE_URL is required");
    process.exit(1);
  }
  const client = postgres(dbUrl, { max: 1 });
  const db = drizzle(client, { schema });
  try {
    await DatabaseContext.run(db, run);
  } finally {
    await client.end();
  }
}

main().catch((e) => {
  console.error(e);
  process.exit(1);
});