/**
 * Strata Core Runtime
 * Main entry point for browser runtime
 */

import { StrataStore, createStore, useStore } from '../store/store.sts';
import { StrataFetch } from '../fetch/fetch.sts';

interface StrataConfig {
  encryptionKey?: number[];
  apiBaseUrl?: string;
  devMode?: boolean;
}

interface BroadcastHandler {
  (data: any): void;
}

class Strata {
  private worker: SharedWorker | null = null;
  private _tabId: string = '';
  private messageHandlers: Map<string, Function[]> = new Map();
  private broadcastHandlers: Map<string, BroadcastHandler[]> = new Map();
  private pendingRequests: Map<string, { resolve: Function; reject: Function }> = new Map();
  private config: StrataConfig = {};
  private _fetch: StrataFetch | null = null;

  get tabId(): string {
    return this._tabId;
  }

  get fetch(): StrataFetch {
    if (!this._fetch) {
      throw new Error('Strata not initialized. Call strata.init() first.');
    }
    return this._fetch;
  }

  async init(config: StrataConfig = {}): Promise<void> {
    this.config = config;

    // Initialize SharedWorker
    if (typeof SharedWorker !== 'undefined') {
      this.worker = new SharedWorker(
        new URL('../worker/shared-worker.sts', import.meta.url),
        { type: 'module', name: 'strata-worker' }
      );

      this.worker.port.onmessage = (event) => this.handleWorkerMessage(event.data);
      this.worker.port.start();

      // Send encryption key if provided
      if (config.encryptionKey) {
        this.worker.port.postMessage({
          type: 'setEncryptionKey',
          key: config.encryptionKey,
        });
      }

      // Wait for connection
      await this.waitForConnection();
    } else {
      // Fallback for browsers without SharedWorker support
      this._tabId = 'tab_' + Math.random().toString(36).slice(2, 10);
      console.warn('SharedWorker not supported, falling back to single-tab mode');
    }

    // Initialize fetch
    this._fetch = new StrataFetch(this);

    // Handle page unload
    window.addEventListener('beforeunload', () => {
      this.disconnect();
    });

    if (config.devMode) {
      (window as any).__STRATA__ = this;
      console.log(`Strata initialized (tabId: ${this._tabId})`);
    }
  }

  private waitForConnection(): Promise<void> {
    return new Promise((resolve) => {
      const handler = (message: any) => {
        if (message.type === 'connected') {
          this._tabId = message.tabId;
          resolve();
        }
      };

      this.addMessageHandler('connected', handler);
    });
  }

  private handleWorkerMessage(message: any) {
    // Handle specific message types
    switch (message.type) {
      case 'connected':
        this._tabId = message.tabId;
        break;
      case 'fetch:response':
      case 'fetch:error':
        this.handleFetchResponse(message);
        break;
      case 'store:value':
        this.handleStoreValue(message);
        break;
      case 'broadcast':
        this.handleBroadcast(message);
        break;
    }

    // Call registered handlers
    const handlers = this.messageHandlers.get(message.type) || [];
    for (const handler of handlers) {
      handler(message);
    }
  }

  private handleFetchResponse(message: any) {
    const pending = this.pendingRequests.get(message.requestId);
    if (pending) {
      if (message.type === 'fetch:error') {
        pending.reject(new Error(message.error));
      } else {
        pending.resolve(message.data);
      }
      this.pendingRequests.delete(message.requestId);
    }
  }

  private handleStoreValue(message: any) {
    // Handled by store subscriptions
  }

  private handleBroadcast(message: any) {
    const handlers = this.broadcastHandlers.get(message.event) || [];
    for (const handler of handlers) {
      handler(message.data);
    }

    // Also call wildcard handlers
    const wildcardHandlers = this.broadcastHandlers.get('*') || [];
    for (const handler of wildcardHandlers) {
      handler({ event: message.event, data: message.data });
    }
  }

  private addMessageHandler(type: string, handler: Function) {
    if (!this.messageHandlers.has(type)) {
      this.messageHandlers.set(type, []);
    }
    this.messageHandlers.get(type)!.push(handler);
  }

  // Public API

  sendToWorker(message: any): void {
    if (this.worker) {
      this.worker.port.postMessage(message);
    }
  }

  async fetchViaWorker(url: string, options?: any): Promise<any> {
    const requestId = crypto.randomUUID();

    return new Promise((resolve, reject) => {
      this.pendingRequests.set(requestId, { resolve, reject });

      this.sendToWorker({
        type: 'fetch',
        url,
        options,
        requestId,
      });

      // Timeout after 30 seconds
      setTimeout(() => {
        if (this.pendingRequests.has(requestId)) {
          this.pendingRequests.delete(requestId);
          reject(new Error('Request timeout'));
        }
      }, 30000);
    });
  }

  broadcast(event: string, data?: any, targetTabs?: string[]): void {
    this.sendToWorker({
      type: 'broadcast',
      event,
      data,
      targetTabs,
    });
  }

  onBroadcast(event: string, handler: BroadcastHandler): () => void {
    if (!this.broadcastHandlers.has(event)) {
      this.broadcastHandlers.set(event, []);
    }
    this.broadcastHandlers.get(event)!.push(handler);

    // Return unsubscribe function
    return () => {
      const handlers = this.broadcastHandlers.get(event);
      if (handlers) {
        const index = handlers.indexOf(handler);
        if (index > -1) {
          handlers.splice(index, 1);
        }
      }
    };
  }

  invalidateCache(pattern: string = '*'): void {
    this.sendToWorker({
      type: 'cache:invalidate',
      pattern,
    });
  }

  private disconnect(): void {
    this.sendToWorker({ type: 'disconnect' });
  }
}

// Singleton instance
export const strata = new Strata();

// Re-exports
export { createStore, useStore };
export type { StrataStore };