#!/usr/bin/env node
// E2E fake `claude` CLI — the metered digest lane's engine.
//
// Unlike the ollama stub (an HTTP server, because ollama-direct talks HTTP),
// claude-code IS a subprocess, so this follows the existing fake-binary idiom:
// a .mjs in e2e/fixtures/bin/ wired in through an env var (CLAUDE_BIN).
//
// Mimics what digestApps.ts's claudeCode.run() actually invokes and parses:
//   claude -p --output-format json [--model <m>]   with the prompt on STDIN
// and expects on stdout the CLI's own JSON WRAPPER, whose `result` field is a
// STRING containing the model's JSON body. Reproducing both layers matters —
// the double parse is exactly where a real integration breaks.
//
// There is no constrained decoding over the CLI, so this deliberately emits the
// contract by hand, the same way the real lane depends on the parser's guards
// rather than on a schema.

import { readFileSync } from "node:fs";
import { installFixtureWatchdog } from "./_watchdog.mjs";

// Never outlive the run that spawned us — see _watchdog.mjs.
installFixtureWatchdog();

const argv = process.argv.slice(2);
function flag(name) {
  const i = argv.indexOf(name);
  return i < 0 ? undefined : argv[i + 1];
}

// The reachability probe digestBatch runs before touching 74k videos — it
// shells out to `claude --version` and treats a non-zero exit as "engine down".
// Answering it is not optional: without this the metered lane fails at the probe
// and never reaches the code the rest of this fake exists to exercise.
if (argv.includes("--version")) {
  process.stdout.write("1.0.0 (fake-claude)\n");
  process.exit(0);
}

// Fail loudly if the invocation drifts: a fake that accepts anything stops
// testing the thing it exists to test.
if (!argv.includes("-p") || flag("--output-format") !== "json") {
  process.stderr.write(
    `[fake-claude] unexpected argv: ${JSON.stringify(argv)}\n`,
  );
  process.exit(2);
}

let stdin = "";
try {
  stdin = readFileSync(0, "utf8");
} catch {
  stdin = "";
}

function hms(total) {
  const n = Math.max(0, Math.floor(total));
  return [Math.floor(n / 3600), Math.floor((n % 3600) / 60), n % 60]
    .map((v) => String(v).padStart(2, "0"))
    .join(":");
}

function toSeconds(clock) {
  const m = /^(\d\d):(\d\d):(\d\d)$/.exec(clock);
  return m ? Number(m[1]) * 3600 + Number(m[2]) * 60 + Number(m[3]) : null;
}

const m = /This section covers (\d\d:\d\d:\d\d) to (\d\d:\d\d:\d\d)/.exec(stdin);
const start = m ? (toSeconds(m[1]) ?? 0) : 0;
const end = m ? (toSeconds(m[2]) ?? 600) : 600;
const span = Math.max(1, end - start);

const body = /"tags"/.test(stdin)
  ? { tags: ["metered lane", "court filings", "podcast"] }
  : {
      chapters: [
        { start: hms(start), title: "Metered lane opening remarks" },
        { start: hms(start + Math.floor(span / 3)), title: "Ruling analysis" },
      ],
    };

process.stdout.write(
  JSON.stringify({
    type: "result",
    is_error: false,
    // The inner body is a STRING, exactly as the real CLI reports it.
    result: JSON.stringify(body),
    total_cost_usd: 0.0123,
    usage: { input_tokens: 1000, output_tokens: 120 },
  }),
);