import { test } from "node:test";
import assert from "node:assert/strict";
import {
  countTextTokens,
  isCodexTokenizerContext,
  resolveTokenizerEncoding,
} from "../../src/shared/utils/tiktokenCounter.ts";

test("countTextTokens returns exact tiktoken count for a known string", () => {
  assert.equal(countTextTokens("hello world"), 2); // cl100k_base
});

test("Codex context selects o200k_base without changing the default", () => {
  assert.equal(resolveTokenizerEncoding(), "cl100k_base");
  assert.equal(resolveTokenizerEncoding({ provider: "codex" }), "o200k_base");
  assert.equal(resolveTokenizerEncoding({ provider: "cx" }), "o200k_base");
  assert.equal(resolveTokenizerEncoding({ model: "codex/gpt-5.6-sol" }), "o200k_base");
  assert.equal(resolveTokenizerEncoding({ model: "cx/gpt-5.6-sol" }), "o200k_base");
  assert.equal(resolveTokenizerEncoding({ provider: "openai", model: "gpt-5.6" }), "cl100k_base");
  assert.equal(isCodexTokenizerContext({ provider: "codex" }), true);
  assert.equal(isCodexTokenizerContext({ provider: "openai" }), false);
});

test("Codex token counting uses the o200k encoder", () => {
  const text = "antidisestablishmentarianism 中文ภาษาไทย";
  assert.notEqual(
    countTextTokens(text, { provider: "codex" }),
    countTextTokens(text, { provider: "openai" })
  );
});

test("countTextTokens handles empty and non-string safely", () => {
  assert.equal(countTextTokens(""), 0);
  assert.equal(countTextTokens(undefined as unknown as string), 0);
});

test("countTextTokens is additive-ish and monotonic for longer text", () => {
  const short = countTextTokens("the quick brown fox");
  const long = countTextTokens("the quick brown fox jumps over the lazy dog");
  assert.ok(long > short);
  assert.ok(short > 0);
});

test("countTextTokens fast-paths strings over 50k chars without tokenizing (worker wedge regression)", () => {
  const big = "user: please review the attached patch\ntext: ".repeat(40_000);
  const start = performance.now();
  const tokens = countTextTokens(big);
  const elapsed = performance.now() - start;
  assert.equal(tokens, Math.ceil(big.length / 4));
  assert.ok(elapsed < 1000, `fast path took ${elapsed.toFixed(0)}ms`);
});

test("countTextTokens strips base64 data URIs before tokenizing (images not counted as text)", () => {
  const png =
    "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==";
  const b64 = png.repeat(60);
  const withImage = countTextTokens(
    `{"image_url":{"url":"data:image/png;base64,${b64}"}}`,
    { provider: "codex" }
  );
  const stripped = countTextTokens('{"image_url":{"url":""}}', { provider: "codex" });
  assert.equal(withImage, stripped);
});

test("countTextTokens does not tokenize huge base64 image payloads (wedge repro)", () => {
  const b64 = "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==";
  const body = `{"image_url":{"url":"data:image/png;base64,${b64.repeat(14_000)}"}}`;
  const start = performance.now();
  const tokens = countTextTokens(body);
  const elapsed = performance.now() - start;
  assert.ok(tokens < 1000, `base64 payload inflates token count to ${tokens}`);
  assert.ok(elapsed < 1000, `took ${elapsed.toFixed(0)}ms`);
});