import { NextRequest, NextResponse } from 'next/server';
import { previewSetupCsvImport } from '@/features/setup/server/csv-preview.service';
import {
  assertBootstrapStepFiles,
  assertBootstrapSetupAvailable,
  assertBootstrapToken,
  BOOTSTRAP_ACTOR_ID,
  BootstrapSetupError,
  setupStepStatusFromPreview,
  toSerializableRecord
} from '@/features/setup/server/setup-bootstrap.service';
import { saveSetupStep, startSetupRun } from '@/features/setup/server/setup-state.service';

function isFile(value: FormDataEntryValue): value is File {
  return (
    typeof value === 'object' &&
    'arrayBuffer' in value &&
    'name' in value &&
    typeof value.name === 'string' &&
    value.name.trim().length > 0
  );
}

export async function POST(request: NextRequest) {
  try {
    await assertBootstrapSetupAvailable();

    const formData = await request.formData();
    assertBootstrapToken(String(formData.get('bootstrapToken') ?? request.headers.get('x-bootstrap-setup-token') ?? ''));

    const stepKey = String(formData.get('stepKey') ?? '');
    const uploadedFiles = Array.from(formData.values()).filter(isFile);

    if (uploadedFiles.length === 0) {
      return NextResponse.json({ message: 'Upload at least one setup CSV file using multipart/form-data.' }, { status: 400 });
    }

    const files = await Promise.all(
      uploadedFiles.map(async (file) => ({
        fileName: file.name,
        bytes: new Uint8Array(await file.arrayBuffer())
      }))
    );

    const step = assertBootstrapStepFiles(stepKey, files);

    await startSetupRun({ actorId: BOOTSTRAP_ACTOR_ID, mode: 'production', targetOrganizationId: null });
    const preview = await previewSetupCsvImport(files);

    await saveSetupStep({
      stepKey: step.stepKey,
      status: setupStepStatusFromPreview(preview),
      inputHash: preview.previewHash,
      output: toSerializableRecord(preview),
      errors: preview.files.flatMap((file) => file.errors),
      warnings: preview.files.flatMap((file) => file.warnings)
    });

    return NextResponse.json(preview);
  } catch (error) {
    if (error instanceof BootstrapSetupError) {
      return NextResponse.json({ message: error.message, details: error.details }, { status: error.status });
    }

    if (error instanceof TypeError && /multipart\/form-data|application\/x-www-form-urlencoded/i.test(error.message)) {
      return NextResponse.json({ message: 'Upload setup CSV files using multipart/form-data.' }, { status: 400 });
    }

    console.error('Bootstrap preview failed');
    if (error instanceof Error) {
      for (const line of (error.stack ?? error.message).split('\n').slice(0, 12)) {
        console.error(line);
      }
    } else {
      console.error(error);
    }
    return NextResponse.json({ message: 'Unable preview bootstrap setup CSV import' }, { status: 500 });
  }
}