1 // Copyright 2016 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "components/offline_pages/core/snapshot_controller.h"
6
7 #include "base/bind.h"
8 #include "base/check_op.h"
9 #include "base/location.h"
10 #include "base/time/time.h"
11 #include "components/offline_pages/core/offline_page_feature.h"
12
13 namespace {
14 // Default delay, in milliseconds, between the main document parsed event and
15 // snapshot. Note: this snapshot might not occur if the OnLoad event and
16 // OnLoad delay elapses first to trigger a final snapshot.
17 const int64_t kDefaultDelayAfterDocumentAvailableMs = 7000;
18
19 // Default delay, in milliseconds, between the main document OnLoad event and
20 // snapshot.
21 const int64_t kDelayAfterDocumentOnLoadCompletedMsForeground = 1000;
22
23 // Delay for testing to keep polling times reasonable.
24 const int64_t kDelayForTests = 0;
25
26 } // namespace
27
28 namespace offline_pages {
29
SnapshotController(const scoped_refptr<base::SingleThreadTaskRunner> & task_runner,SnapshotController::Client * client)30 SnapshotController::SnapshotController(
31 const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
32 SnapshotController::Client* client)
33 : task_runner_(task_runner),
34 client_(client),
35 state_(State::READY),
36 delay_after_document_available_ms_(kDefaultDelayAfterDocumentAvailableMs),
37 delay_after_document_on_load_completed_ms_(
38 kDelayAfterDocumentOnLoadCompletedMsForeground) {
39 if (offline_pages::ShouldUseTestingSnapshotDelay()) {
40 delay_after_document_available_ms_ = kDelayForTests;
41 delay_after_document_on_load_completed_ms_ = kDelayForTests;
42 }
43 }
44
~SnapshotController()45 SnapshotController::~SnapshotController() {}
46
Reset()47 void SnapshotController::Reset() {
48 // Cancel potentially delayed tasks that relate to the previous 'session'.
49 weak_ptr_factory_.InvalidateWeakPtrs();
50 state_ = State::READY;
51 current_page_quality_ = PageQuality::POOR;
52 }
53
Stop()54 void SnapshotController::Stop() {
55 state_ = State::STOPPED;
56 }
57
PendingSnapshotCompleted()58 void SnapshotController::PendingSnapshotCompleted() {
59 // Unless the controller is "stopped", enable the subsequent snapshots.
60 // Stopped state prevents any further snapshots form being started.
61 if (state_ == State::STOPPED)
62 return;
63 state_ = State::READY;
64 }
65
DocumentAvailableInMainFrame()66 void SnapshotController::DocumentAvailableInMainFrame() {
67 DCHECK_EQ(PageQuality::POOR, current_page_quality_);
68 // Post a delayed task to snapshot.
69 task_runner_->PostDelayedTask(
70 FROM_HERE,
71 base::BindOnce(&SnapshotController::MaybeStartSnapshot,
72 weak_ptr_factory_.GetWeakPtr(),
73 PageQuality::FAIR_AND_IMPROVING),
74 base::TimeDelta::FromMilliseconds(delay_after_document_available_ms_));
75 }
76
DocumentOnLoadCompletedInMainFrame()77 void SnapshotController::DocumentOnLoadCompletedInMainFrame() {
78 // Post a delayed task to snapshot and then stop this controller.
79 task_runner_->PostDelayedTask(
80 FROM_HERE,
81 base::BindOnce(&SnapshotController::MaybeStartSnapshotThenStop,
82 weak_ptr_factory_.GetWeakPtr()),
83 base::TimeDelta::FromMilliseconds(
84 delay_after_document_on_load_completed_ms_));
85 }
86
MaybeStartSnapshot(PageQuality updated_page_quality)87 void SnapshotController::MaybeStartSnapshot(PageQuality updated_page_quality) {
88 if (state_ != State::READY)
89 return;
90 DCHECK_LT(current_page_quality_, updated_page_quality);
91 current_page_quality_ = updated_page_quality;
92 state_ = State::SNAPSHOT_PENDING;
93 client_->StartSnapshot();
94 }
95
MaybeStartSnapshotThenStop()96 void SnapshotController::MaybeStartSnapshotThenStop() {
97 MaybeStartSnapshot(PageQuality::HIGH);
98 Stop();
99 }
100
GetDelayAfterDocumentAvailableForTest()101 int64_t SnapshotController::GetDelayAfterDocumentAvailableForTest() {
102 return delay_after_document_available_ms_;
103 }
104
GetDelayAfterDocumentOnLoadCompletedForTest()105 int64_t SnapshotController::GetDelayAfterDocumentOnLoadCompletedForTest() {
106 return delay_after_document_on_load_completed_ms_;
107 }
108
109 } // namespace offline_pages
110