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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

use std::rc::Rc;
use std::{ptr, str};

use encoding_rs::UTF_8;
use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
use ipc_channel::router::ROUTER;
use js::jsapi::{Heap, JSObject, JS_ClearPendingException, Value as JSValue};
use js::jsval::{JSVal, UndefinedValue};
use js::rust::wrappers::{JS_GetPendingException, JS_ParseJSON};
use js::rust::HandleValue;
use js::typedarray::{ArrayBuffer, CreateWith};
use mime::{self, Mime};
use net_traits::request::{
    BodyChunkRequest, BodyChunkResponse, BodySource as NetBodySource, RequestBody,
};
use script_traits::serializable::BlobImpl;
use url::form_urlencoded;

use crate::dom::bindings::cell::DomRefCell;
use crate::dom::bindings::codegen::Bindings::BlobBinding::Blob_Binding::BlobMethods;
use crate::dom::bindings::codegen::Bindings::FormDataBinding::FormDataMethods;
use crate::dom::bindings::codegen::Bindings::XMLHttpRequestBinding::BodyInit;
use crate::dom::bindings::error::{Error, Fallible};
use crate::dom::bindings::refcounted::Trusted;
use crate::dom::bindings::reflector::DomObject;
use crate::dom::bindings::root::DomRoot;
use crate::dom::bindings::str::{DOMString, USVString};
use crate::dom::bindings::trace::RootedTraceableBox;
use crate::dom::blob::{normalize_type_string, Blob};
use crate::dom::formdata::FormData;
use crate::dom::globalscope::GlobalScope;
use crate::dom::htmlformelement::{encode_multipart_form_data, generate_boundary};
use crate::dom::promise::Promise;
use crate::dom::promisenativehandler::{Callback, PromiseNativeHandler};
use crate::dom::readablestream::{get_read_promise_bytes, get_read_promise_done, ReadableStream};
use crate::dom::urlsearchparams::URLSearchParams;
use crate::realms::{enter_realm, AlreadyInRealm, InRealm};
use crate::script_runtime::{CanGc, JSContext};
use crate::task::TaskCanceller;
use crate::task_source::networking::NetworkingTaskSource;
use crate::task_source::{TaskSource, TaskSourceName};

/// The Dom object, or ReadableStream, that is the source of a body.
/// <https://fetch.spec.whatwg.org/#concept-body-source>
#[derive(Clone, PartialEq)]
pub enum BodySource {
    /// A ReadableStream comes with a null-source.
    Null,
    /// Another Dom object as source,
    /// TODO: store the actual object
    /// and re-extract a stream on re-direct.
    Object,
}

/// The reason to stop reading from the body.
enum StopReading {
    /// The stream has errored.
    Error,
    /// The stream is done.
    Done,
}

/// The IPC route handler
/// for <https://fetch.spec.whatwg.org/#concept-request-transmit-body>.
/// This route runs in the script process,
/// and will queue tasks to perform operations
/// on the stream and transmit body chunks over IPC.
#[derive(Clone)]
struct TransmitBodyConnectHandler {
    stream: Trusted<ReadableStream>,
    task_source: NetworkingTaskSource,
    canceller: TaskCanceller,
    bytes_sender: Option<IpcSender<BodyChunkResponse>>,
    control_sender: IpcSender<BodyChunkRequest>,
    in_memory: Option<Vec<u8>>,
    in_memory_done: bool,
    source: BodySource,
}

impl TransmitBodyConnectHandler {
    pub fn new(
        stream: Trusted<ReadableStream>,
        task_source: NetworkingTaskSource,
        canceller: TaskCanceller,
        control_sender: IpcSender<BodyChunkRequest>,
        in_memory: Option<Vec<u8>>,
        source: BodySource,
    ) -> TransmitBodyConnectHandler {
        TransmitBodyConnectHandler {
            stream,
            task_source,
            canceller,
            bytes_sender: None,
            control_sender,
            in_memory,
            in_memory_done: false,
            source,
        }
    }

    /// Reset `in_memory_done`, called when a stream is
    /// re-extracted from the source to support a re-direct.
    pub fn reset_in_memory_done(&mut self) {
        self.in_memory_done = false;
    }

    /// Re-extract the source to support streaming it again for a re-direct.
    /// TODO: actually re-extract the source, instead of just cloning data, to support Blob.
    fn re_extract(&mut self, chunk_request_receiver: IpcReceiver<BodyChunkRequest>) {
        let mut body_handler = self.clone();
        body_handler.reset_in_memory_done();

        ROUTER.add_route(
            chunk_request_receiver.to_opaque(),
            Box::new(move |message| {
                let request = message.to().unwrap();
                match request {
                    BodyChunkRequest::Connect(sender) => {
                        body_handler.start_reading(sender);
                    },
                    BodyChunkRequest::Extract(receiver) => {
                        body_handler.re_extract(receiver);
                    },
                    BodyChunkRequest::Chunk => body_handler.transmit_source(),
                    // Note: this is actually sent from this process
                    // by the TransmitBodyPromiseHandler when reading stops.
                    BodyChunkRequest::Done => {
                        body_handler.stop_reading(StopReading::Done);
                    },
                    // Note: this is actually sent from this process
                    // by the TransmitBodyPromiseHandler when the stream errors.
                    BodyChunkRequest::Error => {
                        body_handler.stop_reading(StopReading::Error);
                    },
                }
            }),
        );
    }

    /// In case of re-direct, and of a source available in memory,
    /// send it all in one chunk.
    ///
    /// TODO: this method should be deprecated
    /// in favor of making `re_extract` actually re-extract a stream from the source.
    /// See #26686
    fn transmit_source(&mut self) {
        if self.in_memory_done {
            // Step 5.1.3
            self.stop_reading(StopReading::Done);
            return;
        }

        if let BodySource::Null = self.source {
            panic!("ReadableStream(Null) sources should not re-direct.");
        }

        if let Some(bytes) = self.in_memory.clone() {
            // The memoized bytes are sent so we mark it as done again
            self.in_memory_done = true;
            let _ = self
                .bytes_sender
                .as_ref()
                .expect("No bytes sender to transmit source.")
                .send(BodyChunkResponse::Chunk(bytes.clone()));
            return;
        }
        warn!("Re-directs for file-based Blobs not supported yet.");
    }

    /// Take the IPC sender sent by `net`, so we can send body chunks with it.
    /// Also the entry point to <https://fetch.spec.whatwg.org/#concept-request-transmit-body>
    fn start_reading(&mut self, sender: IpcSender<BodyChunkResponse>) {
        self.bytes_sender = Some(sender);

        // If we're using an actual ReadableStream, acquire a reader for it.
        if self.source == BodySource::Null {
            let stream = self.stream.clone();
            let _ = self.task_source.queue_with_canceller(
                task!(start_reading_request_body_stream: move || {
                    // Step 1, Let body be request’s body.
                    let rooted_stream = stream.root();

                    // TODO: Step 2, If body is null.

                    // Step 3, get a reader for stream.
                    rooted_stream.start_reading().expect("Couldn't acquire a reader for the body stream.");

                    // Note: this algorithm continues when the first chunk is requested by `net`.
                }),
                &self.canceller,
            );
        }
    }

    /// Drop the IPC sender sent by `net`
    fn stop_reading(&mut self, reason: StopReading) {
        let bytes_sender = self
            .bytes_sender
            .take()
            .expect("Stop reading called multiple times on TransmitBodyConnectHandler.");
        match reason {
            StopReading::Error => {
                let _ = bytes_sender.send(BodyChunkResponse::Error);
            },
            StopReading::Done => {
                let _ = bytes_sender.send(BodyChunkResponse::Done);
            },
        }
    }

    /// Step 4 and following of <https://fetch.spec.whatwg.org/#concept-request-transmit-body>
    fn transmit_body_chunk(&mut self) {
        if self.in_memory_done {
            // Step 5.1.3
            self.stop_reading(StopReading::Done);
            return;
        }

        let stream = self.stream.clone();
        let control_sender = self.control_sender.clone();
        let bytes_sender = self
            .bytes_sender
            .clone()
            .expect("No bytes sender to transmit chunk.");

        // In case of the data being in-memory, send everything in one chunk, by-passing SpiderMonkey.
        if let Some(bytes) = self.in_memory.clone() {
            let _ = bytes_sender.send(BodyChunkResponse::Chunk(bytes));
            // Mark this body as `done` so that we can stop reading in the next tick,
            // matching the behavior of the promise-based flow
            self.in_memory_done = true;
            return;
        }

        let _ = self.task_source.queue_with_canceller(
            task!(setup_native_body_promise_handler: move || {
                let rooted_stream = stream.root();
                let global = rooted_stream.global();

                // Step 4, the result of reading a chunk from body’s stream with reader.
                let promise = rooted_stream.read_a_chunk();

                // Step 5, the parallel steps waiting for and handling the result of the read promise,
                // are a combination of the promise native handler here,
                // and the corresponding IPC route in `component::net::http_loader`.
                let promise_handler = Box::new(TransmitBodyPromiseHandler {
                    bytes_sender: bytes_sender.clone(),
                    stream: rooted_stream.clone(),
                    control_sender: control_sender.clone(),
                });

                let rejection_handler = Box::new(TransmitBodyPromiseRejectionHandler {
                    bytes_sender,
                    stream: rooted_stream,
                    control_sender,
                });

                let handler =
                    PromiseNativeHandler::new(&global, Some(promise_handler), Some(rejection_handler));

                let realm = enter_realm(&*global);
                let comp = InRealm::Entered(&realm);
                promise.append_native_handler(&handler, comp);
            }),
            &self.canceller,
        );
    }
}

/// The handler of read promises of body streams used in
/// <https://fetch.spec.whatwg.org/#concept-request-transmit-body>.
#[derive(Clone, JSTraceable, MallocSizeOf)]
struct TransmitBodyPromiseHandler {
    #[ignore_malloc_size_of = "Channels are hard"]
    #[no_trace]
    bytes_sender: IpcSender<BodyChunkResponse>,
    stream: DomRoot<ReadableStream>,
    #[ignore_malloc_size_of = "Channels are hard"]
    #[no_trace]
    control_sender: IpcSender<BodyChunkRequest>,
}

impl Callback for TransmitBodyPromiseHandler {
    /// Step 5 of <https://fetch.spec.whatwg.org/#concept-request-transmit-body>
    fn callback(&self, cx: JSContext, v: HandleValue, _realm: InRealm, _can_gc: CanGc) {
        let is_done = match get_read_promise_done(cx, &v) {
            Ok(is_done) => is_done,
            Err(_) => {
                // Step 5.5, the "otherwise" steps.
                // TODO: terminate fetch.
                let _ = self.control_sender.send(BodyChunkRequest::Done);
                return self.stream.stop_reading();
            },
        };

        if is_done {
            // Step 5.3, the "done" steps.
            // TODO: queue a fetch task on request to process request end-of-body.
            let _ = self.control_sender.send(BodyChunkRequest::Done);
            return self.stream.stop_reading();
        }

        let chunk = match get_read_promise_bytes(cx, &v) {
            Ok(chunk) => chunk,
            Err(_) => {
                // Step 5.5, the "otherwise" steps.
                let _ = self.control_sender.send(BodyChunkRequest::Error);
                return self.stream.stop_reading();
            },
        };

        // Step 5.1 and 5.2, transmit chunk.
        // Send the chunk to the body transmitter in net::http_loader::obtain_response.
        // TODO: queue a fetch task on request to process request body for request.
        let _ = self.bytes_sender.send(BodyChunkResponse::Chunk(chunk));
    }
}

/// The handler of read promises rejection of body streams used in
/// <https://fetch.spec.whatwg.org/#concept-request-transmit-body>.
#[derive(Clone, JSTraceable, MallocSizeOf)]
struct TransmitBodyPromiseRejectionHandler {
    #[ignore_malloc_size_of = "Channels are hard"]
    #[no_trace]
    bytes_sender: IpcSender<BodyChunkResponse>,
    stream: DomRoot<ReadableStream>,
    #[ignore_malloc_size_of = "Channels are hard"]
    #[no_trace]
    control_sender: IpcSender<BodyChunkRequest>,
}

impl Callback for TransmitBodyPromiseRejectionHandler {
    /// <https://fetch.spec.whatwg.org/#concept-request-transmit-body>
    fn callback(&self, _cx: JSContext, _v: HandleValue, _realm: InRealm, _can_gc: CanGc) {
        // Step 5.4, the "rejection" steps.
        let _ = self.control_sender.send(BodyChunkRequest::Error);
        self.stream.stop_reading();
    }
}

/// The result of <https://fetch.spec.whatwg.org/#concept-bodyinit-extract>
pub struct ExtractedBody {
    pub stream: DomRoot<ReadableStream>,
    pub source: BodySource,
    pub total_bytes: Option<usize>,
    pub content_type: Option<DOMString>,
}

impl ExtractedBody {
    /// Build a request body from the extracted body,
    /// to be sent over IPC to net to use with `concept-request-transmit-body`,
    /// see <https://fetch.spec.whatwg.org/#concept-request-transmit-body>.
    ///
    /// Also returning the corresponding readable stream,
    /// to be stored on the request in script,
    /// and potentially used as part of `consume_body`,
    /// see <https://fetch.spec.whatwg.org/#concept-body-consume-body>
    ///
    /// Transmitting a body over fetch, and consuming it in script,
    /// are mutually exclusive operations, since each will lock the stream to a reader.
    pub fn into_net_request_body(self) -> (RequestBody, DomRoot<ReadableStream>) {
        let ExtractedBody {
            stream,
            total_bytes,
            content_type: _,
            source,
        } = self;

        // First, setup some infra to be used to transmit body
        //  from `components::script` to `components::net`.
        let (chunk_request_sender, chunk_request_receiver) = ipc::channel().unwrap();

        let trusted_stream = Trusted::new(&*stream);

        let global = stream.global();
        let task_source = global.networking_task_source();
        let canceller = global.task_canceller(TaskSourceName::Networking);

        // In case of the data being in-memory, send everything in one chunk, by-passing SM.
        let in_memory = stream.get_in_memory_bytes();

        let net_source = match source {
            BodySource::Null => NetBodySource::Null,
            _ => NetBodySource::Object,
        };

        let mut body_handler = TransmitBodyConnectHandler::new(
            trusted_stream,
            task_source,
            canceller,
            chunk_request_sender.clone(),
            in_memory,
            source,
        );

        ROUTER.add_route(
            chunk_request_receiver.to_opaque(),
            Box::new(move |message| {
                let request = message.to().unwrap();
                match request {
                    BodyChunkRequest::Connect(sender) => {
                        body_handler.start_reading(sender);
                    },
                    BodyChunkRequest::Extract(receiver) => {
                        body_handler.re_extract(receiver);
                    },
                    BodyChunkRequest::Chunk => body_handler.transmit_body_chunk(),
                    // Note: this is actually sent from this process
                    // by the TransmitBodyPromiseHandler when reading stops.
                    BodyChunkRequest::Done => {
                        body_handler.stop_reading(StopReading::Done);
                    },
                    // Note: this is actually sent from this process
                    // by the TransmitBodyPromiseHandler when the stream errors.
                    BodyChunkRequest::Error => {
                        body_handler.stop_reading(StopReading::Error);
                    },
                }
            }),
        );

        // Return `components::net` view into this request body,
        // which can be used by `net` to transmit it over the network.
        let request_body = RequestBody::new(chunk_request_sender, net_source, total_bytes);

        // Also return the stream for this body, which can be used by script to consume it.
        (request_body, stream)
    }

    /// Is the data of the stream of this extracted body available in memory?
    pub fn in_memory(&self) -> bool {
        self.stream.in_memory()
    }
}

/// <https://fetch.spec.whatwg.org/#concept-bodyinit-extract>
pub trait Extractable {
    fn extract(&self, global: &GlobalScope) -> Fallible<ExtractedBody>;
}

impl Extractable for BodyInit {
    // https://fetch.spec.whatwg.org/#concept-bodyinit-extract
    fn extract(&self, global: &GlobalScope) -> Fallible<ExtractedBody> {
        match self {
            BodyInit::String(ref s) => s.extract(global),
            BodyInit::URLSearchParams(ref usp) => usp.extract(global),
            BodyInit::Blob(ref b) => b.extract(global),
            BodyInit::FormData(ref formdata) => formdata.extract(global),
            BodyInit::ArrayBuffer(ref typedarray) => {
                let bytes = typedarray.to_vec();
                let total_bytes = bytes.len();
                let stream = ReadableStream::new_from_bytes(global, bytes);
                Ok(ExtractedBody {
                    stream,
                    total_bytes: Some(total_bytes),
                    content_type: None,
                    source: BodySource::Object,
                })
            },
            BodyInit::ArrayBufferView(ref typedarray) => {
                let bytes = typedarray.to_vec();
                let total_bytes = bytes.len();
                let stream = ReadableStream::new_from_bytes(global, bytes);
                Ok(ExtractedBody {
                    stream,
                    total_bytes: Some(total_bytes),
                    content_type: None,
                    source: BodySource::Object,
                })
            },
            BodyInit::ReadableStream(stream) => {
                // TODO:
                // 1. If the keepalive flag is set, then throw a TypeError.

                if stream.is_locked() || stream.is_disturbed() {
                    return Err(Error::Type(
                        "The body's stream is disturbed or locked".to_string(),
                    ));
                }

                Ok(ExtractedBody {
                    stream: stream.clone(),
                    total_bytes: None,
                    content_type: None,
                    source: BodySource::Null,
                })
            },
        }
    }
}

impl Extractable for Vec<u8> {
    fn extract(&self, global: &GlobalScope) -> Fallible<ExtractedBody> {
        let bytes = self.clone();
        let total_bytes = self.len();
        let stream = ReadableStream::new_from_bytes(global, bytes);
        Ok(ExtractedBody {
            stream,
            total_bytes: Some(total_bytes),
            content_type: None,
            // A vec is used only in `submit_entity_body`.
            source: BodySource::Object,
        })
    }
}

impl Extractable for Blob {
    fn extract(&self, _global: &GlobalScope) -> Fallible<ExtractedBody> {
        let blob_type = self.Type();
        let content_type = if blob_type.as_ref().is_empty() {
            None
        } else {
            Some(blob_type)
        };
        let total_bytes = self.Size() as usize;
        Ok(ExtractedBody {
            stream: self.get_stream(),
            total_bytes: Some(total_bytes),
            content_type,
            source: BodySource::Object,
        })
    }
}

impl Extractable for DOMString {
    fn extract(&self, global: &GlobalScope) -> Fallible<ExtractedBody> {
        let bytes = self.as_bytes().to_owned();
        let total_bytes = bytes.len();
        let content_type = Some(DOMString::from("text/plain;charset=UTF-8"));
        let stream = ReadableStream::new_from_bytes(global, bytes);
        Ok(ExtractedBody {
            stream,
            total_bytes: Some(total_bytes),
            content_type,
            source: BodySource::Object,
        })
    }
}

impl Extractable for FormData {
    fn extract(&self, global: &GlobalScope) -> Fallible<ExtractedBody> {
        let boundary = generate_boundary();
        let bytes = encode_multipart_form_data(&mut self.datums(), boundary.clone(), UTF_8);
        let total_bytes = bytes.len();
        let content_type = Some(DOMString::from(format!(
            "multipart/form-data;boundary={}",
            boundary
        )));
        let stream = ReadableStream::new_from_bytes(global, bytes);
        Ok(ExtractedBody {
            stream,
            total_bytes: Some(total_bytes),
            content_type,
            source: BodySource::Object,
        })
    }
}

impl Extractable for URLSearchParams {
    fn extract(&self, global: &GlobalScope) -> Fallible<ExtractedBody> {
        let bytes = self.serialize_utf8().into_bytes();
        let total_bytes = bytes.len();
        let content_type = Some(DOMString::from(
            "application/x-www-form-urlencoded;charset=UTF-8",
        ));
        let stream = ReadableStream::new_from_bytes(global, bytes);
        Ok(ExtractedBody {
            stream,
            total_bytes: Some(total_bytes),
            content_type,
            source: BodySource::Object,
        })
    }
}

#[derive(Clone, Copy, JSTraceable, MallocSizeOf)]
pub enum BodyType {
    Blob,
    FormData,
    Json,
    Text,
    ArrayBuffer,
}

pub enum FetchedData {
    Text(String),
    Json(RootedTraceableBox<Heap<JSValue>>),
    BlobData(DomRoot<Blob>),
    FormData(DomRoot<FormData>),
    ArrayBuffer(RootedTraceableBox<Heap<*mut JSObject>>),
    JSException(RootedTraceableBox<Heap<JSVal>>),
}

#[derive(Clone, JSTraceable, MallocSizeOf)]
struct ConsumeBodyPromiseRejectionHandler {
    #[ignore_malloc_size_of = "Rc are hard"]
    result_promise: Rc<Promise>,
}

impl Callback for ConsumeBodyPromiseRejectionHandler {
    /// Continuing Step 4 of <https://fetch.spec.whatwg.org/#concept-body-consume-body>
    /// Step 3 of <https://fetch.spec.whatwg.org/#concept-read-all-bytes-from-readablestream>,
    // the rejection steps.
    fn callback(&self, cx: JSContext, v: HandleValue, _realm: InRealm, _can_gc: CanGc) {
        self.result_promise.reject(cx, v);
    }
}

#[derive(Clone, JSTraceable, MallocSizeOf)]
/// The promise handler used to consume the body,
/// <https://fetch.spec.whatwg.org/#concept-body-consume-body>
struct ConsumeBodyPromiseHandler {
    #[ignore_malloc_size_of = "Rc are hard"]
    result_promise: Rc<Promise>,
    stream: Option<DomRoot<ReadableStream>>,
    body_type: DomRefCell<Option<BodyType>>,
    mime_type: DomRefCell<Option<Vec<u8>>>,
    bytes: DomRefCell<Option<Vec<u8>>>,
}

impl ConsumeBodyPromiseHandler {
    /// Step 5 of <https://fetch.spec.whatwg.org/#concept-body-consume-body>
    fn resolve_result_promise(&self, cx: JSContext, can_gc: CanGc) {
        let body_type = self.body_type.borrow_mut().take().unwrap();
        let mime_type = self.mime_type.borrow_mut().take().unwrap();
        let body = self.bytes.borrow_mut().take().unwrap();

        let pkg_data_results = run_package_data_algorithm(cx, body, body_type, mime_type, can_gc);

        match pkg_data_results {
            Ok(results) => {
                match results {
                    FetchedData::Text(s) => self.result_promise.resolve_native(&USVString(s)),
                    FetchedData::Json(j) => self.result_promise.resolve_native(&j),
                    FetchedData::BlobData(b) => self.result_promise.resolve_native(&b),
                    FetchedData::FormData(f) => self.result_promise.resolve_native(&f),
                    FetchedData::ArrayBuffer(a) => self.result_promise.resolve_native(&a),
                    FetchedData::JSException(e) => self.result_promise.reject_native(&e.handle()),
                };
            },
            Err(err) => self.result_promise.reject_error(err),
        }
    }
}

impl Callback for ConsumeBodyPromiseHandler {
    /// Continuing Step 4 of <https://fetch.spec.whatwg.org/#concept-body-consume-body>
    /// Step 3 of <https://fetch.spec.whatwg.org/#concept-read-all-bytes-from-readablestream>.
    fn callback(&self, cx: JSContext, v: HandleValue, _realm: InRealm, can_gc: CanGc) {
        let stream = self
            .stream
            .as_ref()
            .expect("ConsumeBodyPromiseHandler has no stream in callback.");

        let is_done = match get_read_promise_done(cx, &v) {
            Ok(is_done) => is_done,
            Err(err) => {
                stream.stop_reading();
                // When read is fulfilled with a value that doesn't matches with neither of the above patterns.
                return self.result_promise.reject_error(err);
            },
        };

        if is_done {
            // When read is fulfilled with an object whose done property is true.
            self.resolve_result_promise(cx, can_gc);
        } else {
            let chunk = match get_read_promise_bytes(cx, &v) {
                Ok(chunk) => chunk,
                Err(err) => {
                    stream.stop_reading();
                    // When read is fulfilled with a value that matches with neither of the above patterns
                    return self.result_promise.reject_error(err);
                },
            };

            let mut bytes = self
                .bytes
                .borrow_mut()
                .take()
                .expect("No bytes for ConsumeBodyPromiseHandler.");

            // Append the value property to bytes.
            bytes.extend_from_slice(&chunk);

            let global = stream.global();

            // Run the above step again.
            let read_promise = stream.read_a_chunk();

            let promise_handler = Box::new(ConsumeBodyPromiseHandler {
                result_promise: self.result_promise.clone(),
                stream: self.stream.clone(),
                body_type: DomRefCell::new(self.body_type.borrow_mut().take()),
                mime_type: DomRefCell::new(self.mime_type.borrow_mut().take()),
                bytes: DomRefCell::new(Some(bytes)),
            });

            let rejection_handler = Box::new(ConsumeBodyPromiseRejectionHandler {
                result_promise: self.result_promise.clone(),
            });

            let handler =
                PromiseNativeHandler::new(&global, Some(promise_handler), Some(rejection_handler));

            let realm = enter_realm(&*global);
            let comp = InRealm::Entered(&realm);
            read_promise.append_native_handler(&handler, comp);
        }
    }
}

// https://fetch.spec.whatwg.org/#concept-body-consume-body
#[allow(crown::unrooted_must_root)]
pub fn consume_body<T: BodyMixin + DomObject>(object: &T, body_type: BodyType) -> Rc<Promise> {
    let in_realm_proof = AlreadyInRealm::assert();
    let promise = Promise::new_in_current_realm(InRealm::Already(&in_realm_proof));

    // Step 1
    if object.is_disturbed() || object.is_locked() {
        promise.reject_error(Error::Type(
            "The body's stream is disturbed or locked".to_string(),
        ));
        return promise;
    }

    consume_body_with_promise(
        object,
        body_type,
        promise.clone(),
        InRealm::Already(&in_realm_proof),
    );

    promise
}

// https://fetch.spec.whatwg.org/#concept-body-consume-body
#[allow(crown::unrooted_must_root)]
fn consume_body_with_promise<T: BodyMixin + DomObject>(
    object: &T,
    body_type: BodyType,
    promise: Rc<Promise>,
    comp: InRealm,
) {
    let global = object.global();

    // Step 2.
    let stream = match object.body() {
        Some(stream) => stream,
        None => ReadableStream::new_from_bytes(&global, Vec::with_capacity(0)),
    };

    // Step 3.
    if stream.start_reading().is_err() {
        return promise.reject_error(Error::Type(
            "The response's stream is disturbed or locked".to_string(),
        ));
    }

    // Step 4, read all the bytes.
    // Starts here, continues in the promise handler.

    // Step 1 of
    // https://fetch.spec.whatwg.org/#concept-read-all-bytes-from-readablestream
    let read_promise = stream.read_a_chunk();

    let promise_handler = Box::new(ConsumeBodyPromiseHandler {
        result_promise: promise.clone(),
        stream: Some(stream),
        body_type: DomRefCell::new(Some(body_type)),
        mime_type: DomRefCell::new(Some(object.get_mime_type())),
        // Step 2.
        bytes: DomRefCell::new(Some(vec![])),
    });

    let rejection_handler = Box::new(ConsumeBodyPromiseRejectionHandler {
        result_promise: promise,
    });

    let handler = PromiseNativeHandler::new(
        &object.global(),
        Some(promise_handler),
        Some(rejection_handler),
    );
    // We are already in a realm and a script.
    read_promise.append_native_handler(&handler, comp);
}

// https://fetch.spec.whatwg.org/#concept-body-package-data
fn run_package_data_algorithm(
    cx: JSContext,
    bytes: Vec<u8>,
    body_type: BodyType,
    mime_type: Vec<u8>,
    can_gc: CanGc,
) -> Fallible<FetchedData> {
    let mime = &*mime_type;
    let in_realm_proof = AlreadyInRealm::assert_for_cx(cx);
    let global = GlobalScope::from_safe_context(cx, InRealm::Already(&in_realm_proof));
    match body_type {
        BodyType::Text => run_text_data_algorithm(bytes),
        BodyType::Json => run_json_data_algorithm(cx, bytes),
        BodyType::Blob => run_blob_data_algorithm(&global, bytes, mime, can_gc),
        BodyType::FormData => run_form_data_algorithm(&global, bytes, mime),
        BodyType::ArrayBuffer => run_array_buffer_data_algorithm(cx, bytes),
    }
}

fn run_text_data_algorithm(bytes: Vec<u8>) -> Fallible<FetchedData> {
    Ok(FetchedData::Text(
        String::from_utf8_lossy(&bytes).into_owned(),
    ))
}

#[allow(unsafe_code)]
fn run_json_data_algorithm(cx: JSContext, bytes: Vec<u8>) -> Fallible<FetchedData> {
    let json_text = String::from_utf8_lossy(&bytes);
    let json_text: Vec<u16> = json_text.encode_utf16().collect();
    rooted!(in(*cx) let mut rval = UndefinedValue());
    unsafe {
        if !JS_ParseJSON(
            *cx,
            json_text.as_ptr(),
            json_text.len() as u32,
            rval.handle_mut(),
        ) {
            rooted!(in(*cx) let mut exception = UndefinedValue());
            assert!(JS_GetPendingException(*cx, exception.handle_mut()));
            JS_ClearPendingException(*cx);
            return Ok(FetchedData::JSException(RootedTraceableBox::from_box(
                Heap::boxed(exception.get()),
            )));
        }
        let rooted_heap = RootedTraceableBox::from_box(Heap::boxed(rval.get()));
        Ok(FetchedData::Json(rooted_heap))
    }
}

fn run_blob_data_algorithm(
    root: &GlobalScope,
    bytes: Vec<u8>,
    mime: &[u8],
    can_gc: CanGc,
) -> Fallible<FetchedData> {
    let mime_string = if let Ok(s) = String::from_utf8(mime.to_vec()) {
        s
    } else {
        "".to_string()
    };
    let blob = Blob::new(
        root,
        BlobImpl::new_from_bytes(bytes, normalize_type_string(&mime_string)),
        can_gc,
    );
    Ok(FetchedData::BlobData(blob))
}

fn run_form_data_algorithm(
    root: &GlobalScope,
    bytes: Vec<u8>,
    mime: &[u8],
) -> Fallible<FetchedData> {
    let mime_str = if let Ok(s) = str::from_utf8(mime) {
        s
    } else {
        ""
    };
    let mime: Mime = mime_str
        .parse()
        .map_err(|_| Error::Type("Inappropriate MIME-type for Body".to_string()))?;

    // TODO
    // ... Parser for Mime(TopLevel::Multipart, SubLevel::FormData, _)
    // ... is not fully determined yet.
    if mime.type_() == mime::APPLICATION && mime.subtype() == mime::WWW_FORM_URLENCODED {
        let entries = form_urlencoded::parse(&bytes);
        let formdata = FormData::new(None, root);
        for (k, e) in entries {
            formdata.Append(USVString(k.into_owned()), USVString(e.into_owned()));
        }
        return Ok(FetchedData::FormData(formdata));
    }

    Err(Error::Type("Inappropriate MIME-type for Body".to_string()))
}

#[allow(unsafe_code)]
pub fn run_array_buffer_data_algorithm(cx: JSContext, bytes: Vec<u8>) -> Fallible<FetchedData> {
    rooted!(in(*cx) let mut array_buffer_ptr = ptr::null_mut::<JSObject>());
    let arraybuffer = unsafe {
        ArrayBuffer::create(
            *cx,
            CreateWith::Slice(&bytes),
            array_buffer_ptr.handle_mut(),
        )
    };
    if arraybuffer.is_err() {
        return Err(Error::JSFailed);
    }
    let rooted_heap = RootedTraceableBox::from_box(Heap::boxed(array_buffer_ptr.get()));
    Ok(FetchedData::ArrayBuffer(rooted_heap))
}

/// <https://fetch.spec.whatwg.org/#body>
pub trait BodyMixin {
    /// <https://fetch.spec.whatwg.org/#concept-body-disturbed>
    fn is_disturbed(&self) -> bool;
    /// <https://fetch.spec.whatwg.org/#dom-body-body>
    fn body(&self) -> Option<DomRoot<ReadableStream>>;
    /// <https://fetch.spec.whatwg.org/#concept-body-locked>
    fn is_locked(&self) -> bool;
    /// <https://fetch.spec.whatwg.org/#concept-body-mime-type>
    fn get_mime_type(&self) -> Vec<u8>;
}