/**
 * @llm-gateway/client
 *
 * TypeScript client library for the LLM Gateway.
 * Used by all Context X projects: TIP, EO Global Pulse, SwitchBlade,
 * PeerCortex, NOGnet, ShieldX, and CtxEvent.
 *
 * Usage:
 *   import { LLMGatewayClient, createTIPClient } from '@llm-gateway/client';
 *   const client = createTIPClient();
 *   const result = await client.completion({ task_type: 'summarize', input: '...' });
 */

// ============================================================
// Request / Response types
// ============================================================

export interface CompletionRequest {
  /** Identifies which project/service is calling (e.g. 'tip-scraper', 'eo-global-pulse') */
  caller: string;
  /** Task type that maps to a prompt template (e.g. 'summarize', 'classify', 'translate') */
  task_type: string;
  /** The raw input text to process */
  input: string;
  /** Preferred output language */
  language?: 'de' | 'en';
  /** Additional context passed to the prompt template */
  context?: Record<string, unknown>;
  /** Per-request model / behavior overrides */
  options?: {
    /** Override the model (e.g. 'qwen2.5:32b'). Gateway picks a sensible default. */
    model?: string;
    /** Sampling temperature 0–1 */
    temperature?: number;
    /** Max output tokens */
    max_tokens?: number;
    /** Include full validation details in the response */
    return_validation_details?: boolean;
  };
}

export interface CompletionResponse {
  /** Request ID for tracing */
  id: string;
  /** Overall status of the response */
  status: 'approved' | 'warning' | 'pending_review' | 'rejected';
  /** Model confidence score 0–10 */
  confidence: number;
  /** Ollama model that produced the output */
  model: string;
  /** Task type that was processed */
  task_type: string;
  /** End-to-end latency in milliseconds */
  latency_ms: number;
  /** Token usage */
  tokens: { in: number; out: number };
  /** The LLM output text */
  output: string;
  /** Validation details (present when return_validation_details=true) */
  validation?: {
    passed: boolean;
    score: number;
    validators: Record<string, unknown>;
  };
}

export interface ClassifyResponse {
  task_type: string;
  content_type: string;
  language: string;
  complexity: 'low' | 'medium' | 'high';
  requires_facts: boolean;
  suggested_task_types: string[];
}

export interface BatchResponse {
  batch_id: string;
}

export interface HealthResponse {
  status: 'ok' | 'degraded' | 'down';
  ollama: unknown;
  queue: unknown;
}

// ============================================================
// Gateway client
// ============================================================

export class LLMGatewayClient {
  private readonly baseUrl: string;
  private readonly caller: string;
  private readonly timeout: number;

  constructor(config: {
    baseUrl?: string;
    caller: string;
    /** Request timeout in ms (default: 30 000) */
    timeout?: number;
  }) {
    this.baseUrl = config.baseUrl
      ?? process.env['LLM_GATEWAY_URL']
      ?? 'https://llm-gateway.context-x.org';
    this.caller = config.caller;
    this.timeout = config.timeout ?? 30_000;
  }

  // ----------------------------------------------------------
  // Core: completion
  // ----------------------------------------------------------

  async completion(
    params: Omit<CompletionRequest, 'caller'>,
  ): Promise<CompletionResponse> {
    const body: CompletionRequest = { ...params, caller: this.caller };
    return this.post<CompletionResponse>('/v1/completion', body);
  }

  // ----------------------------------------------------------
  // Classify input before routing
  // ----------------------------------------------------------

  async classify(input: string): Promise<ClassifyResponse> {
    return this.post<ClassifyResponse>('/v1/classify', {
      caller: this.caller,
      input,
    });
  }

  // ----------------------------------------------------------
  // Batch: submit multiple tasks, results delivered via webhook
  // ----------------------------------------------------------

  async batch(
    tasks: Array<Omit<CompletionRequest, 'caller'>>,
    webhookUrl: string,
  ): Promise<BatchResponse> {
    return this.post<BatchResponse>('/v1/batch', {
      caller: this.caller,
      tasks,
      webhook_url: webhookUrl,
    });
  }

  // ----------------------------------------------------------
  // Health
  // ----------------------------------------------------------

  async health(): Promise<HealthResponse> {
    const res = await this.fetchWithTimeout(`${this.baseUrl}/health`);
    if (!res.ok) {
      throw new Error(`Health check failed: ${res.status}`);
    }
    return res.json() as Promise<HealthResponse>;
  }

  // ----------------------------------------------------------
  // Graceful degradation — returns null when gateway is unavailable
  // ----------------------------------------------------------

  async safeCompletion(
    params: Omit<CompletionRequest, 'caller'>,
  ): Promise<CompletionResponse | null> {
    try {
      return await this.completion(params);
    } catch {
      // Gateway is down or timed out — caller handles degraded mode
      return null;
    }
  }

  // ----------------------------------------------------------
  // Internal helpers
  // ----------------------------------------------------------

  private async post<T>(path: string, body: unknown): Promise<T> {
    const res = await this.fetchWithTimeout(`${this.baseUrl}${path}`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(body),
    });

    if (!res.ok) {
      const text = await res.text().catch(() => '');
      throw new Error(`Gateway error ${res.status} on ${path}: ${text}`);
    }

    return res.json() as Promise<T>;
  }

  private fetchWithTimeout(url: string, init?: RequestInit): Promise<Response> {
    const controller = new AbortController();
    const timer = setTimeout(() => controller.abort(), this.timeout);

    return fetch(url, { ...init, signal: controller.signal }).finally(() =>
      clearTimeout(timer),
    );
  }
}

// ============================================================
// Project-specific pre-configured factory functions
// ============================================================

/**
 * TIP (Transceiver Intelligence Platform)
 * Long timeout because scraping + AI analysis can take time.
 */
export function createTIPClient(baseUrl?: string): LLMGatewayClient {
  return new LLMGatewayClient({ caller: 'tip-scraper', baseUrl, timeout: 60_000 });
}

/**
 * EO Global Pulse — team collaboration & CRM intelligence
 */
export function createEOPulseClient(baseUrl?: string): LLMGatewayClient {
  return new LLMGatewayClient({ caller: 'eo-global-pulse', baseUrl, timeout: 30_000 });
}

/**
 * SwitchBlade — infrastructure management platform
 */
export function createSwitchBladeClient(baseUrl?: string): LLMGatewayClient {
  return new LLMGatewayClient({ caller: 'switchblade', baseUrl, timeout: 15_000 });
}

/**
 * PeerCortex — BGP/RPKI network intelligence
 * Short timeout: results must be near-real-time for network monitoring.
 */
export function createPeerCortexClient(baseUrl?: string): LLMGatewayClient {
  return new LLMGatewayClient({ caller: 'peercortex', baseUrl, timeout: 8_000 });
}

/**
 * NOGnet — NOG Support Program & event management
 */
export function createNOGnetClient(baseUrl?: string): LLMGatewayClient {
  return new LLMGatewayClient({ caller: 'nognet', baseUrl, timeout: 30_000 });
}

/**
 * ShieldX — LLM prompt injection defense
 */
export function createShieldXClient(baseUrl?: string): LLMGatewayClient {
  return new LLMGatewayClient({ caller: 'shieldx', baseUrl, timeout: 10_000 });
}

/**
 * CtxEvent — event management platform
 */
export function createCtxEventClient(baseUrl?: string): LLMGatewayClient {
  return new LLMGatewayClient({ caller: 'ctxevent', baseUrl, timeout: 20_000 });
}