import { describe, expect, it } from "vite-plus/test";
import * as DateTime from "effect/DateTime";
import { deriveLatestContextWindowSnapshot, formatContextWindowTokens } from "./contextWindow";

describe("V2 context window presentation", () => {
  it("uses retained compaction token data when available", () => {
    const snapshot = deriveLatestContextWindowSnapshot([
      {
        item: {
          id: "compaction-1" as never,
          threadId: "thread-1" as never,
          runId: null,
          nodeId: null,
          providerThreadId: null,
          providerTurnId: null,
          nativeItemRef: null,
          parentItemId: null,
          ordinal: 1,
          status: "completed",
          title: null,
          startedAt: null,
          completedAt: null,
          updatedAt: DateTime.makeUnsafe("2026-06-20T00:00:00.000Z"),
          type: "compaction",
          driver: null,
          beforeTokenCount: 10_000,
          afterTokenCount: 2_000,
        },
      },
    ]);
    expect(snapshot?.usedTokens).toBe(2_000);
    expect(snapshot?.totalProcessedTokens).toBe(10_000);
  });

  it("formats compact token values", () => {
    expect(formatContextWindowTokens(1_500)).toBe("1.5k");
  });
});

describe("live provider-turn usage (#8144)", () => {
  it("prefers the provider's live report over compaction items", () => {
    const snapshot = deriveLatestContextWindowSnapshot([], {
      usedTokens: 42_000,
      maxTokens: 200_000,
      inputTokens: 40_000,
      outputTokens: 2_000,
      updatedAt: "2026-08-27T00:00:00.000Z",
    });
    expect(snapshot).not.toBeNull();
    expect(snapshot?.usedTokens).toBe(42_000);
    expect(snapshot?.maxTokens).toBe(200_000);
    expect(snapshot?.remainingTokens).toBe(158_000);
    expect(snapshot?.usedPercentage).toBe(21);
  });

  it("handles a report without a known context window", () => {
    const snapshot = deriveLatestContextWindowSnapshot([], {
      usedTokens: 42_000,
      updatedAt: "2026-08-27T00:00:00.000Z",
    });
    expect(snapshot?.maxTokens).toBeNull();
    expect(snapshot?.usedPercentage).toBeNull();
  });
});