import assert from "node:assert/strict";
import { readFileSync } from "node:fs";
import test from "node:test";

import {
  batchResultFromToolChunk,
  composeHostFallbackNarration,
  DEFAULT_RETRY_CONSTRAINT,
  isToolInputRejection,
  publicWriteToolCompleted,
  retryConstraintForAttempt,
  turnExpectsEvidenceWrite,
  UNWRITTEN_EVIDENCE_RETRY_CONSTRAINT,
} from "../src/lib/rectification-agentic/v9/host-fallback.ts";

test("host fallback recap uses only batch return lines", () => {
  assert.equal(composeHostFallbackNarration(null), null);
  assert.equal(composeHostFallbackNarration({}), "记下了。");
  assert.equal(
    composeHostFallbackNarration({
      accepted_recaps: [
        { display_date_label: "2016年9月", event_phrase: "入学" },
        { display_date_label: "2020年6月", event_phrase: "毕业" },
      ],
    }),
    "记下了：2016年9月 入学、2020年6月 毕业。",
  );
  assert.equal(
    composeHostFallbackNarration({
      items: [
        { outcome: "accepted", display_date_label: "2018年7月", event_phrase: "入职" },
        { outcome: "rejected", display_date_label: "1999年", event_phrase: "不该出现" },
      ],
    }),
    "记下了：2018年7月 入职。",
  );
});

test("write-tool completion is limited to batch, set-focus and compare", () => {
  const none = new Map<string, "completed" | "failed">([
    ["rectification-read-case", "completed"],
  ]);
  assert.equal(publicWriteToolCompleted(none), false);
  const batch = new Map<string, "completed" | "failed">([
    ["rectification-record-evidence-batch", "completed"],
  ]);
  assert.equal(publicWriteToolCompleted(batch), true);
  const failedBatch = new Map<string, "completed" | "failed">([
    ["rectification-record-evidence-batch", "failed"],
  ]);
  assert.equal(publicWriteToolCompleted(failedBatch), false);
});

test("schema rejection envelopes are not treated as batch recaps or write completion", () => {
  const envelope = {
    error: true,
    message: "Tool input validation failed",
    validationErrors: { errors: [], fields: { kind: "debt" } },
  };
  assert.equal(isToolInputRejection(envelope), true);
  assert.equal(composeHostFallbackNarration(envelope), null);
  assert.equal(batchResultFromToolChunk({
    type: "tool-result",
    payload: { toolName: "rectification-record-evidence-batch", result: envelope },
  }), null);
  assert.equal(isToolInputRejection({ error: true, message: "no fields" }), false);
});

test("year fallback is gone; only explicit evidence expectedWrite triggers the guard", () => {
  assert.equal(turnExpectsEvidenceWrite("opening", "evidence"), false);
  assert.equal(turnExpectsEvidenceWrite("read_only", "none"), false);
  assert.equal(turnExpectsEvidenceWrite("evidence", "evidence"), true);
  assert.equal(turnExpectsEvidenceWrite("evidence", "none"), false);
  assert.equal(turnExpectsEvidenceWrite("evidence", "unknown"), false);
  assert.equal(turnExpectsEvidenceWrite("evidence", undefined), false);
  assert.equal(retryConstraintForAttempt("evidence_not_written"), UNWRITTEN_EVIDENCE_RETRY_CONSTRAINT);
  assert.equal(retryConstraintForAttempt("empty_stream"), DEFAULT_RETRY_CONSTRAINT);
});

test("case snapshot receipts expose host_fallback origin from the durable phase", () => {
  const route = readFileSync(
    new URL("../src/app/api/rectification/cases/[caseId]/route.ts", import.meta.url),
    "utf8",
  );
  assert.match(route, /answer_origin: "host_fallback"/);
  assert.match(route, /answer\.host_fallback/);
});