import { expect, it, vi } from "vitest";

import { AnalysisCancelledError } from "../domain/analysisErrorCore.js";
import { inspectWebPageInputSchema } from "../domain/browserObservation.js";
import { CdpCaptureEvents } from "./CdpCaptureEvents.js";
import type { CdpConnection } from "./CdpConnection.js";
import { captureScripts } from "./CdpPageCaptureScripts.js";
import type { CaptureContext } from "./CdpPageCapture.js";
import type { CapturedScript } from "./CdpCaptureEventTypes.js";

const script = (scriptId: string): CapturedScript => ({
  scriptId,
  rawUrl: `https://example.test/${scriptId}.js`,
  url: `https://example.test/${scriptId}.js`,
  origin: "https://example.test",
  hash: scriptId,
  length: null,
  isModule: false,
  language: "JavaScript",
  sourceMapUrl: null,
  sourceMapRawUrl: null,
  executionContextKey: null,
  frameId: null,
});

const capture = async (
  sources: Readonly<Record<string, string>>,
  includeScriptSources = true,
  signal?: AbortSignal,
) => {
  const input = inspectWebPageInputSchema.parse({
    cdp_endpoint: "http://127.0.0.1:9222",
    target_id: "page-1",
    allowed_origins: ["https://example.test"],
    observation_ms: 0,
    include_script_sources: includeScriptSources,
  });
  const events = new CdpCaptureEvents(input, new Set(input.allowed_origins));
  for (const id of Object.keys(sources)) events.scripts.set(id, script(id));
  const send = vi.fn(async (method: string, params: unknown) => {
    if (method !== "Debugger.getScriptSource")
      throw new Error(`Unexpected CDP command: ${method}`);
    const scriptId = (params as { scriptId: string }).scriptId;
    return { scriptSource: sources[scriptId] };
  });
  const context = {
    connection: { send } as unknown as CdpConnection,
    sessionId: undefined,
    operation: "inspect_web_page",
    discovery: undefined,
    target: undefined,
    input,
    ...(signal === undefined ? {} : { signal }),
  } as unknown as CaptureContext;
  const result = await captureScripts({
    context,
    events,
    rawResources: [],
    resources: [],
    frameIds: new Set(),
  });
  return { result, events, send };
};

it("admits a prefix and fitting suffix around an oversized script source", async () => {
  const prefix = "p".repeat(16 * 1024 * 1024);
  const oversized = "o".repeat(17 * 1024 * 1024);
  const suffix = "s".repeat(1024 * 1024);
  const { result, events } = await capture({ prefix, oversized, suffix });
  const byId = new Map(
    result.inventory.items.map((item) => [item.cdp_hash, item.source]),
  );

  expect(byId.get("prefix")).toMatchObject({ included: true });
  expect(byId.get("oversized")).toEqual({
    included: false,
    reason:
      "script source was omitted because the aggregate 32 MiB source budget was exhausted",
  });
  expect(byId.get("suffix")).toMatchObject({ included: true });
  expect(events.completeness.snapshot().excluded).toContainEqual({
    section: "script_sources",
    reason: "resource_budget_exhausted",
    count: 1,
  });
});

it("preserves the caller cancellation reason when a source read is pending", async () => {
  const controller = new AbortController();
  const reason = new AnalysisCancelledError("inspect_web_page");
  const input = inspectWebPageInputSchema.parse({
    cdp_endpoint: "http://127.0.0.1:9222",
    target_id: "page-1",
    allowed_origins: ["https://example.test"],
    observation_ms: 0,
    include_script_sources: true,
  });
  const events = new CdpCaptureEvents(input, new Set(input.allowed_origins));
  events.scripts.set("first", script("first"));
  const context = {
    connection: {
      send: async () => {
        controller.abort(reason);
        throw new AnalysisCancelledError("inspect_web_page");
      },
    } as unknown as CdpConnection,
    sessionId: undefined,
    operation: "inspect_web_page",
    discovery: undefined,
    target: undefined,
    input,
    signal: controller.signal,
  } as unknown as CaptureContext;

  await expect(
    captureScripts({
      context,
      events,
      rawResources: [],
      resources: [],
      frameIds: new Set(),
    }),
  ).rejects.toMatchObject({ _tag: "AnalysisCancelledError", cause: reason });
});

it("stops source reads at the shared collection deadline and retains metadata", async () => {
  vi.useFakeTimers();
  try {
    const input = inspectWebPageInputSchema.parse({
      cdp_endpoint: "http://127.0.0.1:9222",
      target_id: "page-1",
      allowed_origins: ["https://example.test"],
      observation_ms: 0,
      include_script_sources: true,
    });
    const events = new CdpCaptureEvents(input, new Set(input.allowed_origins));
    events.scripts.set("first", script("first"));
    events.scripts.set("second", script("second"));
    const send = vi.fn(
      (
        _method: string,
        _params: unknown,
        _sessionId: string | undefined,
        signal?: AbortSignal,
      ) =>
        new Promise((_resolve, reject) => {
          signal?.addEventListener(
            "abort",
            () => reject(new AnalysisCancelledError("inspect_web_page")),
            { once: true },
          );
        }),
    );
    const context = {
      connection: { send } as unknown as CdpConnection,
      sessionId: undefined,
      operation: "inspect_web_page",
      discovery: undefined,
      target: undefined,
      input,
    } as unknown as CaptureContext;
    const pending = captureScripts({
      context,
      events,
      rawResources: [],
      resources: [],
      frameIds: new Set(),
    });

    await vi.advanceTimersByTimeAsync(20_000);
    const result = await pending;

    expect(send).toHaveBeenCalledTimes(1);
    expect(result.inventory.items.map((item) => item.source)).toEqual([
      {
        included: false,
        reason:
          "script source was omitted because the 20-second source collection deadline elapsed",
      },
      {
        included: false,
        reason:
          "script source was omitted because the 20-second source collection deadline elapsed",
      },
    ]);
    expect(events.completeness.snapshot().excluded).toContainEqual({
      section: "script_sources",
      reason: "resource_budget_exhausted",
      count: 2,
    });
  } finally {
    vi.useRealTimers();
  }
});

it("leaves source-off capture unchanged and does not issue source reads", async () => {
  const { result, events, send } = await capture({ first: "unused" }, false);

  expect(send).not.toHaveBeenCalled();
  expect(result.inventory.items[0]?.source).toEqual({
    included: false,
    reason: "source capture was not selected",
  });
  expect(events.completeness.snapshot().excluded).toContainEqual({
    section: "script_sources",
    reason: "not_approved",
    count: 1,
  });
});