1import type { DebuggerInfo, Device as MetroDevice } from 'metro-inspector-proxy';
2import fetch from 'node-fetch';
3import type WS from 'ws';
4
5import { MetroBundlerDevServer } from '../MetroBundlerDevServer';
6import { DebuggerScriptSourceHandler } from './handlers/DebuggerScriptSource';
7import { NetworkResponseHandler } from './handlers/NetworkResponse';
8import { PageReloadHandler } from './handlers/PageReload';
9import { VscodeCompatHandler } from './handlers/VscodeCompat';
10import { DeviceRequest, InspectorHandler, DebuggerRequest } from './handlers/types';
11
12export function createInspectorDeviceClass(
13  metroBundler: MetroBundlerDevServer,
14  MetroDeviceClass: typeof MetroDevice
15) {
16  return class ExpoInspectorDevice extends MetroDeviceClass implements InspectorHandler {
17    /** All handlers that should be used to intercept or reply to CDP events */
18    public handlers: InspectorHandler[] = [
19      new NetworkResponseHandler(),
20      new DebuggerScriptSourceHandler(this),
21      new PageReloadHandler(metroBundler),
22      new VscodeCompatHandler(),
23    ];
24
25    onDeviceMessage(message: any, info: DebuggerInfo): boolean {
26      return this.handlers.some((handler) => handler.onDeviceMessage?.(message, info) ?? false);
27    }
28
29    onDebuggerMessage(message: any, info: DebuggerInfo): boolean {
30      return this.handlers.some((handler) => handler.onDebuggerMessage?.(message, info) ?? false);
31    }
32
33    /** Hook into the message life cycle to answer more complex CDP messages */
34    async _processMessageFromDevice(message: DeviceRequest<any>, info: DebuggerInfo) {
35      if (!this.onDeviceMessage(message, info)) {
36        await super._processMessageFromDevice(message, info);
37      }
38    }
39
40    /** Hook into the message life cycle to answer more complex CDP messages */
41    _interceptMessageFromDebugger(
42      request: DebuggerRequest,
43      info: DebuggerInfo,
44      socket: WS
45    ): boolean {
46      // Note, `socket` is the exact same as `info.socket`
47      if (this.onDebuggerMessage(request, info)) {
48        return true;
49      }
50
51      return super._interceptMessageFromDebugger(request, info, socket);
52    }
53
54    /**
55     * Overwrite the default text fetcher, to load sourcemaps from sources other than `localhost`.
56     * @todo Cedric: remove the custom `DebuggerScriptSource` handler when switching over to `metro@>=0.75.1`
57     * @see https://github.com/facebook/metro/blob/77f445f1bcd2264ad06174dbf8d542bc75834d29/packages/metro-inspector-proxy/src/Device.js#L573-L588
58     * @since [email protected]
59     */
60    async _fetchText(url: URL): Promise<string> {
61      const LENGTH_LIMIT_BYTES = 350_000_000; // 350mb
62
63      const response = await fetch(url);
64      if (!response.ok) {
65        throw new Error(`Received status ${response.status} while fetching: ${url}`);
66      }
67
68      const contentLength = response.headers.get('Content-Length');
69      if (contentLength && Number(contentLength) > LENGTH_LIMIT_BYTES) {
70        throw new Error('Expected file size is too large (more than 350mb)');
71      }
72
73      const text = await response.text();
74      if (Buffer.byteLength(text, 'utf8') > LENGTH_LIMIT_BYTES) {
75        throw new Error('File size is too large (more than 350mb)');
76      }
77
78      return text;
79    }
80  };
81}
82