/**
 * WorthDoing.ai
 * Author: Simon-Pierre Boucher
 * Contact: contact@spboucher.ai
 * File: src/lib/anthropic/client.ts
 * Description: Anthropic adapter — singleton client and model configuration for the agent.
 */
import Anthropic from "@anthropic-ai/sdk";
import { env } from "@/lib/env";

const globalForAnthropic = globalThis as unknown as { __wdAnthropic?: Anthropic };

export function anthropic(): Anthropic {
  if (!globalForAnthropic.__wdAnthropic) {
    globalForAnthropic.__wdAnthropic = new Anthropic({
      apiKey: env().ANTHROPIC_API_KEY,
      maxRetries: 3,
    });
  }
  return globalForAnthropic.__wdAnthropic;
}

export function agentModel(): string {
  return env().CLAUDE_AGENT_MODEL;
}

export function synthesisModel(): string {
  return env().CLAUDE_SYNTHESIS_MODEL;
}

/** Approximate USD cost for a request, for observability (list prices, claude-opus-5). */
export function estimateCostUsd(model: string, inputTokens: number, outputTokens: number): number {
  // Per-million-token list prices; fall back to Opus-tier if unknown.
  const prices: Record<string, { in: number; out: number }> = {
    "claude-opus-5": { in: 5, out: 25 },
    "claude-sonnet-5": { in: 3, out: 15 },
    "claude-haiku-4-5": { in: 1, out: 5 },
  };
  const p = prices[model] ?? { in: 5, out: 25 };
  return (inputTokens * p.in + outputTokens * p.out) / 1_000_000;
}