import type { AgentMessage } from "@mariozechner/pi-agent-core";
import type { AssistantMessage } from "@mariozechner/pi-ai";
import { describe, expect, it } from "vitest";

import {
  buildBootstrapContextFiles,
  formatAssistantErrorText,
  isContextOverflowError,
  sanitizeGoogleTurnOrdering,
} from "./pi-embedded-helpers.js";
import {
  DEFAULT_AGENTS_FILENAME,
  type WorkspaceBootstrapFile,
} from "./workspace.js";

const makeFile = (
  overrides: Partial<WorkspaceBootstrapFile>,
): WorkspaceBootstrapFile => ({
  name: DEFAULT_AGENTS_FILENAME,
  path: "/tmp/AGENTS.md",
  content: "",
  missing: false,
  ...overrides,
});

describe("buildBootstrapContextFiles", () => {
  it("keeps missing markers", () => {
    const files = [makeFile({ missing: true, content: undefined })];
    expect(buildBootstrapContextFiles(files)).toEqual([
      {
        path: DEFAULT_AGENTS_FILENAME,
        content: "[MISSING] Expected at: /tmp/AGENTS.md",
      },
    ]);
  });

  it("skips empty or whitespace-only content", () => {
    const files = [makeFile({ content: "   \n  " })];
    expect(buildBootstrapContextFiles(files)).toEqual([]);
  });

  it("truncates large bootstrap content", () => {
    const head = `HEAD-${"a".repeat(6000)}`;
    const tail = `${"b".repeat(3000)}-TAIL`;
    const long = `${head}${tail}`;
    const files = [makeFile({ content: long })];
    const [result] = buildBootstrapContextFiles(files);
    expect(result?.content).toContain(
      "[...truncated, read AGENTS.md for full content...]",
    );
    expect(result?.content.length).toBeLessThan(long.length);
    expect(result?.content.startsWith(long.slice(0, 120))).toBe(true);
    expect(result?.content.endsWith(long.slice(-120))).toBe(true);
  });
});

describe("isContextOverflowError", () => {
  it("matches known overflow hints", () => {
    const samples = [
      "request_too_large",
      "Request exceeds the maximum size",
      "context length exceeded",
      "Maximum context length",
      "413 Request Entity Too Large",
    ];
    for (const sample of samples) {
      expect(isContextOverflowError(sample)).toBe(true);
    }
  });

  it("ignores unrelated errors", () => {
    expect(isContextOverflowError("rate limit exceeded")).toBe(false);
  });
});

describe("formatAssistantErrorText", () => {
  const makeAssistantError = (errorMessage: string): AssistantMessage =>
    ({
      stopReason: "error",
      errorMessage,
    }) as AssistantMessage;

  it("returns a friendly message for context overflow", () => {
    const msg = makeAssistantError("request_too_large");
    expect(formatAssistantErrorText(msg)).toContain("Context overflow");
  });
});

describe("sanitizeGoogleTurnOrdering", () => {
  it("prepends a synthetic user turn when history starts with assistant", () => {
    const input = [
      {
        role: "assistant",
        content: [
          { type: "toolCall", id: "call_1", name: "bash", arguments: {} },
        ],
      },
    ] satisfies AgentMessage[];

    const out = sanitizeGoogleTurnOrdering(input);
    expect(out[0]?.role).toBe("user");
    expect(out[1]?.role).toBe("assistant");
  });

  it("is a no-op when history starts with user", () => {
    const input = [{ role: "user", content: "hi" }] satisfies AgentMessage[];
    const out = sanitizeGoogleTurnOrdering(input);
    expect(out).toBe(input);
  });
});