/**
 * Framework adapter factory
 *
 * Detects the available framework and returns the appropriate adapter.
 */

import type {
  AdapterDetectionResult,
  AdapterFactoryOptions,
  FrameworkAdapter,
} from './interfaces.js';
import { vanillaAdapter } from './vanilla-adapter.js';
import { vue3Adapter } from './vue-adapter.js';
import { reactAdapter } from './react-adapter.js';

/**
 * Default adapter list
 */
const DEFAULT_ADAPTERS = [
  vue3Adapter,
  reactAdapter,
  vanillaAdapter,
] as const;

/**
 * Detect the best adapter for the current page
 */
export function detectAdapter(
  options: AdapterFactoryOptions = {}
): AdapterDetectionResult {
  const {
    preferredAdapter,
    allowFallback = true,
    customAdapters = [],
  } = options;

  const allAdapters = [...customAdapters, ...DEFAULT_ADAPTERS] as FrameworkAdapter[];

  // If preferred adapter is specified and available, use it
  if (preferredAdapter) {
    const preferred = allAdapters.find((a) => a.name === preferredAdapter);
    if (preferred && preferred.isAvailable()) {
      return {
        adapter: preferred,
        confidence: 1,
        reason: `Preferred adapter '${preferredAdapter}' is available`,
      };
    }
  }

  // Detect available adapters
  const available = allAdapters.filter((a) => a.isAvailable());

  if (available.length === 0) {
    if (allowFallback) {
      return {
        adapter: vanillaAdapter,
        confidence: 0.1,
        reason: 'No framework detected, falling back to vanilla adapter',
      };
    }

    return {
      adapter: null,
      confidence: 0,
      reason: 'No framework adapter available',
    };
  }

  // Prioritize non-vanilla adapters
  const frameworkAdapters = available.filter((a) => a.name !== 'vanilla');

  if (frameworkAdapters.length > 0) {
    // Return the first available framework adapter
    const adapter = frameworkAdapters[0];
    return {
      adapter,
      confidence: 0.9,
      reason: `Framework '${adapter.name}' detected`,
    };
  }

  // Only vanilla is available
  return {
    adapter: vanillaAdapter,
    confidence: 0.5,
    reason: 'Using vanilla adapter',
  };
}

/**
 * Get the best adapter for the current page
 */
export function getAdapter(
  options: AdapterFactoryOptions = {}
): FrameworkAdapter | null {
  const result = detectAdapter(options);
  return result.adapter;
}

/**
 * Create an adapter with the given options
 */
export function createAdapter(
  options: AdapterFactoryOptions = {}
): FrameworkAdapter | null {
  return getAdapter(options);
}

/**
 * Get all available adapters
 */
export function getAvailableAdapters(
  customAdapters: FrameworkAdapter[] = []
): FrameworkAdapter[] {
  const allAdapters = [...customAdapters, ...DEFAULT_ADAPTERS] as FrameworkAdapter[];
  return allAdapters.filter((a) => a.isAvailable());
}

/**
 * Get adapter by name
 */
export function getAdapterByName(
  name: string,
  customAdapters: FrameworkAdapter[] = []
): FrameworkAdapter | null {
  const allAdapters = [...customAdapters, ...DEFAULT_ADAPTERS] as FrameworkAdapter[];
  return allAdapters.find((a) => a.name === name) || null;
}