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

/* 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 dom_struct::dom_struct;
use js::rust::{HandleObject, MutableHandleValue};

use super::bindings::codegen::Bindings::IntersectionObserverBinding::{
    IntersectionObserverCallback, IntersectionObserverMethods,
};
use super::bindings::codegen::UnionTypes::ElementOrDocument;
use super::types::{Element, IntersectionObserverEntry};
use crate::dom::bindings::codegen::Bindings::IntersectionObserverBinding::IntersectionObserverInit;
use crate::dom::bindings::reflector::{reflect_dom_object_with_proto, Reflector};
use crate::dom::bindings::root::DomRoot;
use crate::dom::bindings::str::DOMString;
use crate::dom::window::Window;
use crate::script_runtime::{CanGc, JSContext};

/// The Intersection Observer interface
///
/// > The IntersectionObserver interface can be used to observe changes in the intersection
/// > of an intersection root and one or more target Elements.
///
/// <https://w3c.github.io/IntersectionObserver/#intersection-observer-interface>
#[dom_struct]
pub struct IntersectionObserver {
    reflector_: Reflector,

    /// > This callback will be invoked when there are changes to a target’s intersection
    /// > with the intersection root, as per the processing model.
    /// <https://w3c.github.io/IntersectionObserver/#intersection-observer-callback>
    #[ignore_malloc_size_of = "Rc are hard"]
    callback: Rc<IntersectionObserverCallback>,
}

impl IntersectionObserver {
    pub fn new_inherited(
        callback: Rc<IntersectionObserverCallback>,
        _init: &IntersectionObserverInit,
    ) -> Self {
        Self {
            reflector_: Reflector::new(),
            callback,
        }
    }

    fn new(
        window: &Window,
        proto: Option<HandleObject>,
        callback: Rc<IntersectionObserverCallback>,
        init: &IntersectionObserverInit,
        can_gc: CanGc,
    ) -> DomRoot<Self> {
        let observer = Box::new(Self::new_inherited(callback, init));
        reflect_dom_object_with_proto(observer, window, proto, can_gc)
    }
}

impl IntersectionObserverMethods<crate::DomTypeHolder> for IntersectionObserver {
    /// > The root provided to the IntersectionObserver constructor, or null if none was provided.
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-root>
    fn GetRoot(&self) -> Option<ElementOrDocument> {
        None
    }

    /// > Offsets applied to the root intersection rectangle, effectively growing or
    /// > shrinking the box that is used to calculate intersections. These offsets are only
    /// > applied when handling same-origin-domain targets; for cross-origin-domain targets
    /// > they are ignored.
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-rootmargin>
    fn RootMargin(&self) -> DOMString {
        DOMString::new()
    }

    /// > Offsets are applied to scrollports on the path from intersection root to target,
    /// > effectively growing or shrinking the clip rects used to calculate intersections.
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-scrollmargin>
    fn ScrollMargin(&self) -> DOMString {
        DOMString::new()
    }

    /// > A list of thresholds, sorted in increasing numeric order, where each threshold
    /// > is a ratio of intersection area to bounding box area of an observed target.
    /// > Notifications for a target are generated when any of the thresholds are crossed
    /// > for that target. If no options.threshold was provided to the IntersectionObserver
    /// > constructor, or the sequence is empty, the value of this attribute will be [0].
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-thresholds>
    fn Thresholds(&self, _context: JSContext, _retval: MutableHandleValue) {}

    /// > A number indicating the minimum delay in milliseconds between notifications from
    /// > this observer for a given target.
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-delay>
    fn Delay(&self) -> i32 {
        0
    }

    /// > A boolean indicating whether this IntersectionObserver will track changes in a target’s visibility.
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-trackvisibility>
    fn TrackVisibility(&self) -> bool {
        false
    }

    /// > Run the observe a target Element algorithm, providing this and target.
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-observe>
    fn Observe(&self, _target: &Element) {}

    /// > Run the unobserve a target Element algorithm, providing this and target.
    ///
    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-unobserve>
    fn Unobserve(&self, _target: &Element) {}

    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-disconnect>
    fn Disconnect(&self) {}

    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-takerecords>
    fn TakeRecords(&self) -> Vec<DomRoot<IntersectionObserverEntry>> {
        vec![]
    }

    /// <https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-intersectionobserver>
    fn Constructor(
        window: &Window,
        proto: Option<HandleObject>,
        can_gc: CanGc,
        callback: Rc<IntersectionObserverCallback>,
        init: &IntersectionObserverInit,
    ) -> DomRoot<IntersectionObserver> {
        Self::new(window, proto, callback, init, can_gc)
    }
}