/**
 * Phase 2 of the legacy migration: pull signed EOI PDFs + berth spec PDFs from
 * the LEGACY MinIO (`client-portal` bucket) and deposit them into the CRM's own
 * storage, linking them to the already-migrated deals + berths.
 *
 * Two storage worlds, kept strictly separate:
 *   - LEGACY read  : a dedicated `minio` Client using LEGACY_MINIO_* env.
 *   - CRM write    : `getStorageBackend()` (the CRM's own configured storage).
 *     ⚠ We NEVER route legacy creds through getStorageBackend — that would
 *     write INTO prod. LEGACY_MINIO_* is distinct from the CRM's MINIO_*.
 *
 * Idempotent + re-runnable: an EOI is skipped once its `documents.signedFileId`
 * is set; a berth is skipped once it has a `currentPdfVersionId`.
 *
 * Run AFTER `migrate-from-nocodb.ts --apply`:
 *   LEGACY_MINIO_ACCESS_KEY=… LEGACY_MINIO_SECRET_KEY=… \
 *   pnpm tsx scripts/migration/backfill-documents.ts --port-slug port-nimara [--dry-run]
 */
import 'dotenv/config';
import { randomUUID } from 'node:crypto';
import { Client as MinioClient } from 'minio';
import { and, eq, isNull } from 'drizzle-orm';

import { db, closeDb } from '@/lib/db';
import { ports } from '@/lib/db/schema/ports';
import { berths } from '@/lib/db/schema/berths';
import { documents, files } from '@/lib/db/schema/documents';
import { clients } from '@/lib/db/schema/clients';
import { getStorageBackend } from '@/lib/storage';
import { buildStoragePath } from '@/lib/minio';
import { ensureEntityFolder } from '@/lib/services/document-folders.service';
import { uploadBerthPdf } from '@/lib/services/berth-pdf.service';
import { normalizeName } from '@/lib/dedup/normalize';
import { SUPER_ADMIN_USER_ID } from '@/lib/db/seed-bootstrap';

const DRY = process.argv.includes('--dry-run');
const slugArg = (() => {
  const i = process.argv.indexOf('--port-slug');
  return i >= 0 ? (process.argv[i + 1] ?? 'port-nimara') : 'port-nimara';
})();

const LEGACY_BUCKET = process.env.LEGACY_MINIO_BUCKET ?? 'client-portal';
const legacy = new MinioClient({
  endPoint: process.env.LEGACY_MINIO_ENDPOINT ?? 's3.portnimara.com',
  port: 443,
  useSSL: true,
  accessKey: process.env.LEGACY_MINIO_ACCESS_KEY ?? '',
  secretKey: process.env.LEGACY_MINIO_SECRET_KEY ?? '',
});

/** Levenshtein edit distance — conservative fuzzy name matching for legacy
 *  spelling/format drift (Koshbin↔Khoshbin, Costanzo↔Constanzo). */
function lev(a: string, b: string): number {
  const m = a.length;
  const n = b.length;
  if (!m) return n;
  if (!n) return m;
  let prev = Array.from({ length: n + 1 }, (_, i) => i);
  for (let i = 1; i <= m; i++) {
    const cur = [i];
    for (let j = 1; j <= n; j++) {
      cur[j] = Math.min(
        prev[j]! + 1,
        cur[j - 1]! + 1,
        prev[j - 1]! + (a[i - 1] === b[j - 1] ? 0 : 1),
      );
    }
    prev = cur;
  }
  return prev[n]!;
}

function streamToBuffer(stream: NodeJS.ReadableStream): Promise<Buffer> {
  return new Promise((resolve, reject) => {
    const chunks: Buffer[] = [];
    stream.on('data', (c: Buffer) => chunks.push(c));
    stream.on('end', () => resolve(Buffer.concat(chunks)));
    stream.on('error', reject);
  });
}

interface LegacyObject {
  name: string;
  size: number;
}
function listLegacy(prefix: string): Promise<LegacyObject[]> {
  return new Promise((resolve, reject) => {
    const out: LegacyObject[] = [];
    const stream = legacy.listObjectsV2(LEGACY_BUCKET, prefix, true);
    stream.on('data', (o) => {
      if (o.name && !o.name.endsWith('/')) out.push({ name: o.name, size: o.size ?? 0 });
    });
    stream.on('end', () => resolve(out));
    stream.on('error', reject);
  });
}

async function resolvePort(slug: string): Promise<{ id: string; slug: string }> {
  const [p] = await db
    .select({ id: ports.id, slug: ports.slug })
    .from(ports)
    .where(eq(ports.slug, slug))
    .limit(1);
  if (!p) throw new Error(`No port with slug "${slug}"`);
  return p;
}

// ─── Berth PDFs ──────────────────────────────────────────────────────────────
// client-portal/Berth-PDFs/<ts>-Berth_Spec_Sheet_<Mooring>.pdf  → berth by mooring.
async function backfillBerthPdfs(port: { id: string; slug: string }) {
  const objs = (await listLegacy('Berth-PDFs/')).filter((o) => /\.pdf$/i.test(o.name));
  const berthRows = await db
    .select({ id: berths.id, mooring: berths.mooringNumber, cur: berths.currentPdfVersionId })
    .from(berths)
    .where(eq(berths.portId, port.id));
  const byMooring = new Map(berthRows.map((b) => [b.mooring, b]));

  let attached = 0;
  let skipped = 0;
  let unmatched = 0;
  for (const o of objs) {
    const m = o.name.match(/Berth_Spec_Sheet_([A-Za-z]+\d+)\.pdf$/i);
    if (!m) {
      unmatched++;
      continue;
    }
    const mooring = `${m[1]!.replace(/[a-z]+/g, (s) => s.toUpperCase())}`
      .toUpperCase()
      .replace(/([A-Z]+)0*(\d+)/, '$1$2');
    const berth = byMooring.get(mooring);
    if (!berth) {
      console.log(`  [berth] no berth for mooring "${mooring}" (${o.name})`);
      unmatched++;
      continue;
    }
    if (berth.cur) {
      skipped++;
      continue;
    }
    if (DRY) {
      attached++;
      continue;
    }
    const buf = await streamToBuffer(await legacy.getObject(LEGACY_BUCKET, o.name));
    await uploadBerthPdf({
      berthId: berth.id,
      portId: port.id,
      buffer: buf,
      fileName: o.name.split('/').pop() ?? `${mooring}.pdf`,
      uploadedBy: SUPER_ADMIN_USER_ID,
    });
    attached++;
  }
  return { total: objs.length, attached, skipped, unmatched };
}

// ─── Signed EOIs ─────────────────────────────────────────────────────────────
// client-portal/EOIs/<Client Name>/<file>.pdf  → match by normalized client name.
async function backfillEois(port: { id: string; slug: string }) {
  // Signed EOIs live under EOIs/<Name>/ and (some) under Client Documents/<Name>/.
  const objs = [...(await listLegacy('EOIs/')), ...(await listLegacy('Client Documents/'))].filter(
    (o) => /\.pdf$/i.test(o.name) && /eoi|sign/i.test(o.name),
  );
  // Index the best signed PDF per normalized folder (client) name.
  const byName = new Map<string, { key: string; size: number }>();
  for (const o of objs) {
    const parts = o.name.split('/'); // <prefix> / <Name> / <file>.pdf
    if (parts.length < 3) continue;
    const folder = (parts[1] ?? '').replace(/_/g, ' '); // "Matt_Ciaccio" → "Matt Ciaccio"
    const norm = normalizeName(folder).display;
    if (!norm) continue;
    const isSigned = /sign/i.test(o.name);
    const prev = byName.get(norm);
    // Prefer a "signed" file; among those, the largest (the full signed PDF).
    if (!prev || (isSigned && o.size > prev.size)) byName.set(norm, { key: o.name, size: o.size });
  }

  // Migrated EOI documents missing a signed file.
  const docRows = await db
    .select({ id: documents.id, interestId: documents.interestId, clientId: documents.clientId })
    .from(documents)
    .where(
      and(
        eq(documents.portId, port.id),
        eq(documents.documentType, 'eoi'),
        isNull(documents.signedFileId),
      ),
    );

  const backend = await getStorageBackend();
  let attached = 0;
  let unmatched = 0;
  const unresolved: string[] = [];
  for (const doc of docRows) {
    const clientId = doc.clientId;
    if (!clientId) {
      unmatched++;
      continue;
    }
    const [c] = await db
      .select({ name: clients.fullName })
      .from(clients)
      .where(eq(clients.id, clientId))
      .limit(1);
    if (!c) {
      unmatched++;
      continue;
    }
    const target = normalizeName(c.name).display;
    let match = byName.get(target);
    if (!match && target.length >= 6) {
      // Conservative fuzzy fallback: best edit-distance ≤ 2 on the full name.
      let bestDist = 3;
      for (const [name, v] of byName) {
        const d = lev(name, target);
        if (d < bestDist) {
          bestDist = d;
          match = v;
        }
      }
    }
    if (!match) {
      unresolved.push(c.name);
      unmatched++;
      continue;
    }
    if (DRY) {
      attached++;
      continue;
    }
    // Pull legacy bytes → write to CRM storage → files row → link signedFileId.
    const buf = await streamToBuffer(await legacy.getObject(LEGACY_BUCKET, match.key));
    const key = buildStoragePath(port.slug, 'eoi-signed', doc.id, randomUUID(), 'pdf');
    const putRes = await backend.put(key, buf, {
      contentType: 'application/pdf',
      sizeBytes: buf.length,
    });
    // File into the client's entity folder (mirrors handleDocumentCompleted's
    // owner-folder filing). files.interestId still scopes the row to the deal;
    // interest "Deal" folders aren't system-managed (chk_system_folder_shape).
    const folder = await ensureEntityFolder(port.id, 'client', clientId, SUPER_ADMIN_USER_ID);
    const fileName = match.key.split('/').pop() ?? 'eoi-signed.pdf';
    await db.transaction(async (tx) => {
      const [f] = await tx
        .insert(files)
        .values({
          portId: port.id,
          filename: fileName,
          originalName: fileName,
          storagePath: putRes.key,
          mimeType: 'application/pdf',
          sizeBytes: String(putRes.sizeBytes),
          category: 'eoi',
          folderId: folder.id,
          clientId,
          interestId: doc.interestId,
          uploadedBy: 'system',
        })
        .returning({ id: files.id });
      if (!f) throw new Error('files insert returned no row');
      await tx
        .update(documents)
        .set({ signedFileId: f.id, status: 'completed', isManualUpload: true })
        .where(eq(documents.id, doc.id));
    });
    attached++;
  }
  return {
    totalBlobs: objs.length,
    indexedClients: byName.size,
    candidates: docRows.length,
    attached,
    unmatched,
    unresolved,
  };
}

async function main() {
  if (!process.env.LEGACY_MINIO_ACCESS_KEY || !process.env.LEGACY_MINIO_SECRET_KEY) {
    console.error(
      'Set LEGACY_MINIO_ACCESS_KEY + LEGACY_MINIO_SECRET_KEY (legacy MinIO read creds).',
    );
    process.exit(1);
  }
  const port = await resolvePort(slugArg);
  console.log(
    `[backfill] port=${port.slug} legacy-bucket=${LEGACY_BUCKET} ${DRY ? '(DRY RUN)' : ''}`,
  );

  console.log('[backfill] Berth PDFs…');
  const berthRes = await backfillBerthPdfs(port);
  console.log(
    `  berth PDFs: ${berthRes.total} blobs → ${berthRes.attached} attached, ${berthRes.skipped} already had one, ${berthRes.unmatched} unmatched`,
  );

  console.log('[backfill] Signed EOIs…');
  const eoiRes = await backfillEois(port);
  console.log(
    `  EOIs: ${eoiRes.totalBlobs} blobs (${eoiRes.indexedClients} client folders) · ${eoiRes.candidates} migrated EOI docs needing a file → ${eoiRes.attached} attached, ${eoiRes.unmatched} unmatched`,
  );
  if (eoiRes.unresolved.length > 0) {
    console.log(`  ⚠ EOI docs with no name-matched legacy PDF (${eoiRes.unresolved.length}):`);
    for (const n of eoiRes.unresolved.slice(0, 25)) console.log(`     - ${n}`);
  }

  await closeDb();
  process.exit(0);
}

main().catch(async (err) => {
  console.error('[backfill] failed:', err);
  await closeDb().catch(() => {});
  process.exit(1);
});