import { NativeModules, Platform } from 'react-native';
import type {
  AgeDeclarationModuleType,
  AgeRangeResult,
  SetThresholdsResult,
} from './types';

const LINKING_ERROR =
  `The package 'react-native-age-declaration' doesn't seem to be linked. Make sure: \n\n` +
  Platform.select({ ios: "- Run 'pod install' in the ios directory\n", default: '' }) +
  Platform.select({
    android:
      "- You have added the package to your app's build.gradle dependencies\n" +
      "- You have added AgeDeclarationPackage to your MainApplication.java\n",
    default: '',
  }) +
  '- You rebuilt the app after installing the package\n';

const AgeDeclarationModule: AgeDeclarationModuleType = NativeModules.AgeDeclarationModule
  ? NativeModules.AgeDeclarationModule
  : new Proxy(
      {},
      {
        get() {
          throw new Error(LINKING_ERROR);
        },
      }
    ) as AgeDeclarationModuleType;

/**
 * Sets the age range thresholds for the application
 *
 * **Requirements:**
 * - First threshold is mandatory
 * - Values must be 1-18 (inclusive)
 * - Must be in ascending order
 * - Minimum 2-year separation between values
 *
 * @param thresholds - Array of age thresholds
 * @returns Promise that resolves when thresholds are set
 *
 * @example
 * ```typescript
 * import AgeDeclaration from 'react-native-age-declaration';
 *
 * // Set age thresholds at app startup
 * await AgeDeclaration.setAgeThresholds([13, 15, 18]);
 * ```
 */
export function setAgeThresholds(thresholds: number[]): Promise<SetThresholdsResult> {
  if (!Array.isArray(thresholds)) {
    return Promise.reject(new Error('Thresholds must be an array of numbers'));
  }

  if (thresholds.length === 0) {
    return Promise.reject(new Error('At least one threshold is required'));
  }

  // Validate that all values are numbers
  if (!thresholds.every((t) => typeof t === 'number' && !isNaN(t))) {
    return Promise.reject(new Error('All thresholds must be valid numbers'));
  }

  return AgeDeclarationModule.setAgeThresholds(thresholds);
}

/**
 * Requests age range information from the platform
 *
 * **Important:**
 * - Must call `setAgeThresholds()` first
 * - iOS: Requires iOS 26.0+ with DeclaredAgeRange framework
 * - Android: Requires Android 15+ with Google Play Services
 *
 * @returns Promise that resolves with age verification result
 *
 * @example
 * ```typescript
 * import AgeDeclaration from 'react-native-age-declaration';
 *
 * const result = await AgeDeclaration.requestAgeRange();
 *
 * switch (result.status) {
 *   case 'verified':
 *     console.log('User meets age requirements');
 *     break;
 *   case 'not_verified':
 *     console.log('User does not meet age requirements');
 *     break;
 *   case 'unknown':
 *     console.log('Age verification status unknown');
 *     break;
 *   case 'not_available_yet':
 *     console.log('API not available on this device/OS version');
 *     break;
 * }
 * ```
 */
export function requestAgeRange(): Promise<AgeRangeResult> {
  return AgeDeclarationModule.requestAgeRange();
}

/**
 * Checks if age range API is supported on this device
 *
 * @returns Promise that resolves to true if supported
 *
 * @example
 * ```typescript
 * import AgeDeclaration from 'react-native-age-declaration';
 *
 * const supported = await AgeDeclaration.isSupported();
 *
 * if (supported) {
 *   await AgeDeclaration.setAgeThresholds([13, 18]);
 *   const result = await AgeDeclaration.requestAgeRange();
 * } else {
 *   console.log('Age verification not supported on this device');
 * }
 * ```
 */
export function isSupported(): Promise<boolean> {
  return AgeDeclarationModule.isSupported();
}

// Default export
export default {
  setAgeThresholds,
  requestAgeRange,
  isSupported,
};

// Export types
export type { AgeRangeResult, SetThresholdsResult } from './types';