File size: 4,488 Bytes
bee6636
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
import { unrewriteUrl } from "../shared/rewriters/url";
import { ScramjetClient } from "./client";

export class ScramjetServiceWorkerRuntime {
	recvport: MessagePort;
	constructor(public client: ScramjetClient) {
		// @ts-ignore
		self.onconnect = (cevent: MessageEvent) => {
			const port = cevent.ports[0];
			dbg.log("sw", "connected");

			port.addEventListener("message", (event) => {
				console.log("sw", event.data);
				if ("scramjet$type" in event.data) {
					if (event.data.scramjet$type === "init") {
						this.recvport = event.data.scramjet$port;
						this.recvport.postMessage({ scramjet$type: "init" });
					} else {
						handleMessage.call(this, client, event.data);
					}
				}
			});

			port.start();
		};
	}

	hook() {
		// @ts-ignore
		this.client.global.registration = {
			// TODO IMPLEMENT SCOPES
			scope: this.client.url.href,
			active: {
				scriptURL: this.client.url.href,
				state: "activated",
				onstatechange: null,
				onerror: null,

				postMessage: () => {},
				addEventListener: () => {},
				removeEventListener: () => {},
				dispatchEvent: (_e: Event): boolean => {
					return false;
				},
			},
			showNotification: async () => {},
			unregister: async () => true,
			//@ts-ignore
			update: async () => {},
			installing: null,
			waiting: null,
		};

		// @ts-ignore
		this.client.global.ServiceWorkerGlobalScope = this.client.global;
	}
}

function handleMessage(

	this: ScramjetServiceWorkerRuntime,

	client: ScramjetClient,

	data: MessageW2R

) {
	const port = this.recvport;
	const type = data.scramjet$type;
	const token = data.scramjet$token;
	const handlers = client.eventcallbacks.get(self);

	if (type === "fetch") {
		dbg.log("ee", data);
		const fetchhandlers = handlers.filter((event) => event.event === "fetch");
		if (!fetchhandlers) return;

		for (const handler of fetchhandlers) {
			const request = data.scramjet$request;

			const Request = client.natives["Request"];
			const fakeRequest = new Request(unrewriteUrl(request.url), {
				body: request.body,
				headers: new Headers(request.headers),
				method: request.method,
				mode: "same-origin",
			});

			Object.defineProperty(fakeRequest, "destination", {
				value: request.destinitation,
			});

			// TODO: clean up, maybe put into a class
			const fakeFetchEvent: any = new Event("fetch");
			fakeFetchEvent.request = fakeRequest;
			let responded = false;
			fakeFetchEvent.respondWith = (response: Response | Promise<Response>) => {
				responded = true;
				(async () => {
					response = await response;
					const message: MessageR2W = {
						scramjet$type: "fetch",
						scramjet$token: token,
						scramjet$response: {
							body: response.body,
							headers: Array.from(response.headers.entries()),
							status: response.status,
							statusText: response.statusText,
						},
					};

					dbg.log("sw", "responding", message);
					port.postMessage(message, [response.body]);
				})();
			};

			dbg.log("to fn", fakeFetchEvent);
			handler.proxiedCallback(trustEvent(fakeFetchEvent));
			if (!responded) {
				console.log("sw", "no response");
				port.postMessage({
					scramjet$type: "fetch",
					scramjet$token: token,
					scramjet$response: false,
				});
			}
		}
	}
}

function trustEvent(event: Event): Event {
	return new Proxy(event, {
		get(target, prop, _reciever) {
			if (prop === "isTrusted") return true;

			return Reflect.get(target, prop);
		},
	});
}

export type TransferrableResponse = {
	body: ReadableStream;
	headers: [string, string][];
	status: number;
	statusText: string;
};

export type TransferrableRequest = {
	body: ReadableStream;
	headers: [string, string][];
	destinitation: RequestDestination;
	method: Request["method"];
	mode: Request["mode"];
	url: string;
};

type FetchResponseMessage = {
	scramjet$type: "fetch";
	scramjet$response: TransferrableResponse;
};

type FetchRequestMessage = {
	scramjet$type: "fetch";
	scramjet$request: TransferrableRequest;
};

// r2w = runtime to (service) worker

type MessageTypeR2W = FetchResponseMessage;
type MessageTypeW2R = FetchRequestMessage;

type MessageCommon = {
	scramjet$type: string;
	scramjet$token: number;
};

export type MessageR2W = MessageCommon & MessageTypeR2W;
export type MessageW2R = MessageCommon &
	MessageTypeW2R & { scramjet$port?: MessagePort };