import * as fs from "node:fs";
import * as path from "node:path";

export type ModelAccessSurface = "pi" | "openrouter" | "openai" | "chatgpt-cyber" | "anthropic-fable" | "anthropic-mythos" | "sakana-fugu" | "hermes-moa" | "other";
export type ModelAccessStatus = "available" | "blocked" | "missing" | "unknown";

export interface ModelAccessProbe {
  surface: ModelAccessSurface;
  command: string;
  status: ModelAccessStatus;
  evidence: string;
  model?: string;
}

export interface ModelAccessReceiptOptions {
  probes: ModelAccessProbe[];
  output?: string;
  freshnessHours?: number;
  now?: Date;
}

export interface ModelAccessReceipt {
  schema: "fable.model_access.receipt.v1";
  createdAt: string;
  probes: ModelAccessProbe[];
  summary: Record<ModelAccessStatus, number>;
  freshness: { hours: number; expiresAt: string };
  decision: "verified" | "partial" | "blocked";
  claims: string[];
  reasons: string[];
}

export function createModelAccessReceipt(opts: ModelAccessReceiptOptions): ModelAccessReceipt {
  const now = opts.now ?? new Date();
  const freshnessHours = opts.freshnessHours ?? 24;
  const summary = opts.probes.reduce(
    (acc, probe) => ({ ...acc, [probe.status]: acc[probe.status] + 1 }),
    { available: 0, blocked: 0, missing: 0, unknown: 0 },
  );
  const reasons: string[] = [];
  if (opts.probes.length === 0) reasons.push("no model access probes supplied");
  if (opts.probes.some((probe) => probe.surface === "chatgpt-cyber" && probe.status !== "available")) reasons.push("ChatGPT Cyber access not verified");
  if (summary.unknown > 0) reasons.push("one or more model surfaces are unknown");

  return {
    schema: "fable.model_access.receipt.v1",
    createdAt: now.toISOString(),
    probes: opts.probes,
    summary,
    freshness: { hours: freshnessHours, expiresAt: new Date(now.getTime() + freshnessHours * 60 * 60 * 1000).toISOString() },
    decision: opts.probes.length === 0 || summary.available === 0 ? "blocked" : reasons.length ? "partial" : "verified",
    claims: opts.probes.filter((probe) => probe.status === "available").map((probe) => `${probe.surface}${probe.model ? `:${probe.model}` : ""} available`),
    reasons,
  };
}

export function writeModelAccessReceipt(file: string, receipt: ModelAccessReceipt): string {
  fs.mkdirSync(path.dirname(file), { recursive: true });
  fs.writeFileSync(file, `${JSON.stringify(receipt, null, 2)}\n`);
  return file;
}