import dotenv from 'dotenv';
import { z } from 'zod';

dotenv.config({ quiet: true });

const optionalText = z.preprocess(
  (value) => (value === '' || value === undefined ? undefined : value),
  z.string().optional(),
);

const optionalUrl = z.preprocess(
  (value) => (value === '' || value === undefined ? undefined : value),
  z.string().url().optional(),
);

const optionalPort = z.preprocess(
  (value) => (value === '' || value === undefined ? undefined : value),
  z.coerce.number().int().positive().optional(),
);

const envSchema = z.object({
  NODE_ENV: z.enum(['development', 'test', 'production']).default('development'),
  PORT: z.coerce.number().int().positive().default(4000),
  CORS_ORIGIN: z.string().min(1).default('http://localhost:5173'),
  DB_HOST: optionalText,
  DB_PORT: optionalPort,
  DB_USER: optionalText,
  DB_PASSWORD: optionalText,
  DB_NAME: optionalText,
  DB_SSL: z.preprocess(
    (value) => (value === '' || value === undefined ? undefined : value),
    z.enum(['true', 'false']).optional(),
  ),
  S3_BUCKET: optionalText,
  S3_REGION: optionalText,
  S3_ACCESS_KEY_ID: optionalText,
  S3_SECRET_ACCESS_KEY: optionalText,
  SENDGRID_API_KEY: optionalText,
  SENDGRID_SANDBOX_MODE: z.preprocess((value) => {
    if (value === undefined || value === '') {
      return false;
    }

    if (value === 'true' || value === true) {
      return true;
    }

    if (value === 'false' || value === false) {
      return false;
    }

    return value;
  }, z.boolean()),
  SENDGRID_WEBHOOK_VERIFICATION_KEY: optionalText,
  ADMIN_NOTIFY_EMAILS: optionalText,
  MAIL_FROM: optionalText,
  APP_BASE_URL: optionalUrl,
  JWT_SECRET: optionalText,
  TOKEN_PEPPER: optionalText,
  RECAPTCHA_SITE_KEY: optionalText,
  RECAPTCHA_SECRET_KEY: optionalText,
  CAPTCHA_ENABLED: z.preprocess((value) => {
    if (value === undefined || value === '') {
      return false;
    }

    if (value === 'true' || value === true) {
      return true;
    }

    if (value === 'false' || value === false) {
      return false;
    }

    return value;
  }, z.boolean()),
  ADMIN_EMAIL: optionalText,
  ADMIN_PASSWORD: optionalText,
  DATA_ENCRYPTION_KEY: optionalText,
  WEASYPRINT_BIN: optionalText,
  PDF_REGENERATE: z.preprocess(
    (value) => (value === '' || value === undefined ? undefined : value),
    z.enum(['never', 'changed', 'always']).default('never'),
  ),
  TRUST_PROXY: z.preprocess((value) => {
    if (value === undefined || value === '') {
      return false;
    }

    if (value === 'true' || value === true) {
      return true;
    }

    if (value === 'false' || value === false) {
      return false;
    }

    return value;
  }, z.boolean()),
});

const parsed = envSchema.safeParse(process.env);

if (!parsed.success) {
  console.error('Invalid environment variables', parsed.error.flatten().fieldErrors);
  process.exit(1);
}

if (parsed.data.NODE_ENV === 'production' && parsed.data.PDF_REGENERATE !== 'never') {
  console.error(
    `PDF_REGENERATE=${parsed.data.PDF_REGENERATE} is not allowed in production: stored consent and agreement PDFs must not change. Unset it or set PDF_REGENERATE=never.`,
  );
  process.exit(1);
}

export const env = parsed.data;