import assert from "node:assert/strict";
import test from "node:test";
import {
  cachedSystemMessage,
  mergePromptCacheUsage,
  promptCacheUsage,
} from "../src/lib/agent-generation-settings.ts";

test("normalizes AI SDK cache token details", () => {
  assert.deepEqual(promptCacheUsage({
    inputTokenDetails: { cacheReadTokens: 120, cacheWriteTokens: 30, noCacheTokens: 10 },
  }), { readTokens: 120, writeTokens: 30, noCacheTokens: 10 });
});

test("normalizes OpenAI and legacy cache usage", () => {
  assert.deepEqual(promptCacheUsage({ prompt_tokens_details: { cached_tokens: 45 } }), {
    readTokens: 45,
    writeTokens: 0,
    noCacheTokens: 0,
  });
  assert.deepEqual(promptCacheUsage({ cachedInputTokens: 12, cacheCreationInputTokens: 8 }), {
    readTokens: 12,
    writeTokens: 8,
    noCacheTokens: 0,
  });
});

test("merges cache usage and only reports a hit when reads exist", () => {
  assert.deepEqual(mergePromptCacheUsage([
    { readTokens: 4, writeTokens: 5, noCacheTokens: 6 },
    { readTokens: 7, writeTokens: 0, noCacheTokens: 1 },
  ]), { readTokens: 11, writeTokens: 5, noCacheTokens: 7 });
  assert.equal(promptCacheUsage({ inputTokenDetails: { cacheWriteTokens: 5 } })?.readTokens, 0);
  assert.equal(promptCacheUsage({ inputTokenDetails: { cacheReadTokens: 5 } })?.readTokens, 5);
});

test("adds an Anthropic cache boundary and safely degrades for other providers", () => {
  assert.deepEqual(cachedSystemMessage("stable", "anthropic/claude-sonnet"), {
    role: "system",
    content: "stable",
    providerOptions: { anthropic: { cacheControl: { type: "ephemeral" } } },
  });
  assert.equal(cachedSystemMessage("stable", "openai/gpt-5"), null);
  assert.equal(cachedSystemMessage("stable", { providerId: "deepseek" }), null);
});