import { z } from "zod";

/**
 * Helper to parse boolean from string
 */
const booleanString = z
  .string()
  .optional()
  .default("false")
  .transform((val) => val === "true");

/**
 * Environment variables schema validation using Zod
 */
export const envSchema = z.object({
  // Environment
  NODE_ENV: z
    .enum(["development", "production", "test"])
    .default("development"),
  PORT: z.coerce.number().default(3005),

  // Database
  DATABASE_URL: z.string().url(),
  // AI Engine
  AI_ENGINE_URL: z.string().url().default("http://localhost:8000"),
  AI_ENGINE_MODE: z.enum(["v28-pro-max", "dual"]).default("v28-pro-max"),

  // JWT
  JWT_SECRET: z.string().min(32),
  JWT_ACCESS_EXPIRATION: z.string().default("15m"),
  JWT_REFRESH_EXPIRATION: z.string().default("7d"),

  // Redis
  REDIS_ENABLED: z
    .string()
    .transform((val) => val === "true")
    .default("false" as any),
  REDIS_HOST: z.string().default("localhost"),
  REDIS_PORT: z.coerce.number().default(6379),
  REDIS_PASSWORD: z.string().optional(),

  // i18n
  DEFAULT_LANGUAGE: z.string().default("en"),
  FALLBACK_LANGUAGE: z.string().default("en"),

  // Gemini AI
  ENABLE_GEMINI: z
    .string()
    .transform((val) => val === "true")
    .default("false" as any),
  GOOGLE_API_KEY: z.string().optional(),
  GEMINI_DEFAULT_MODEL: z.string().default("gemini-2.5-flash"),

  // Social Poster
  SOCIAL_POSTER_ENABLED: z
    .string()
    .transform((val) => val === "true")
    .default("false" as any),
  TWITTER_API_KEY: z.string().optional(),
  TWITTER_API_SECRET: z.string().optional(),
  TWITTER_ACCESS_TOKEN: z.string().optional(),
  TWITTER_ACCESS_SECRET: z.string().optional(),
  META_PAGE_ACCESS_TOKEN: z.string().optional(),
  META_PAGE_ID: z.string().optional(),
  META_IG_USER_ID: z.string().optional(),

  // Optional Features
  ENABLE_MAIL: booleanString,
  ENABLE_S3: booleanString,
  ENABLE_WEBSOCKET: booleanString,
  ENABLE_MULTI_TENANCY: booleanString,

  // Mail (Optional)
  MAIL_HOST: z.string().optional(),
  MAIL_PORT: z.coerce.number().optional(),
  MAIL_USER: z.string().optional(),
  MAIL_PASSWORD: z.string().optional(),
  MAIL_FROM: z.string().optional(),

  // S3 (Optional)
  S3_ENDPOINT: z.string().optional(),
  S3_ACCESS_KEY: z.string().optional(),
  S3_SECRET_KEY: z.string().optional(),
  S3_BUCKET: z.string().optional(),
  S3_REGION: z.string().optional(),

  // Throttle
  THROTTLE_TTL: z.coerce.number().default(60000),
  THROTTLE_LIMIT: z.coerce.number().default(100),
});

export type EnvConfig = z.infer<typeof envSchema>;

/**
 * Validate environment variables
 */
export function validateEnv(config: Record<string, unknown>): EnvConfig {
  const result = envSchema.safeParse(config);

  if (!result.success) {
    const errors = result.error.issues.map(
      (err) => `${err.path.join(".")}: ${err.message}`,
    );
    throw new Error(`Environment validation failed:\n${errors.join("\n")}`);
  }

  return result.data;
}