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

/* 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 dom_struct::dom_struct;
use euclid::{Point2D, RigidTransform3D};
use webxr_api::{self, Floor, Frame, Space};

use crate::dom::bindings::codegen::Bindings::XRReferenceSpaceBinding::{
    XRReferenceSpaceMethods, XRReferenceSpaceType,
};
use crate::dom::bindings::inheritance::Castable;
use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
use crate::dom::bindings::root::{Dom, DomRoot};
use crate::dom::globalscope::GlobalScope;
use crate::dom::xrrigidtransform::XRRigidTransform;
use crate::dom::xrsession::{cast_transform, ApiPose, BaseTransform, XRSession};
use crate::dom::xrspace::XRSpace;
use crate::script_runtime::CanGc;

#[dom_struct]
pub struct XRReferenceSpace {
    xrspace: XRSpace,
    offset: Dom<XRRigidTransform>,
    ty: XRReferenceSpaceType,
}

impl XRReferenceSpace {
    pub fn new_inherited(
        session: &XRSession,
        offset: &XRRigidTransform,
        ty: XRReferenceSpaceType,
    ) -> XRReferenceSpace {
        XRReferenceSpace {
            xrspace: XRSpace::new_inherited(session),
            offset: Dom::from_ref(offset),
            ty,
        }
    }

    #[allow(unused)]
    pub fn new(
        global: &GlobalScope,
        session: &XRSession,
        ty: XRReferenceSpaceType,
        can_gc: CanGc,
    ) -> DomRoot<XRReferenceSpace> {
        let offset = XRRigidTransform::identity(global, can_gc);
        Self::new_offset(global, session, ty, &offset)
    }

    #[allow(unused)]
    pub fn new_offset(
        global: &GlobalScope,
        session: &XRSession,
        ty: XRReferenceSpaceType,
        offset: &XRRigidTransform,
    ) -> DomRoot<XRReferenceSpace> {
        reflect_dom_object(
            Box::new(XRReferenceSpace::new_inherited(session, offset, ty)),
            global,
        )
    }

    pub fn space(&self) -> Space {
        let base = match self.ty {
            XRReferenceSpaceType::Local => webxr_api::BaseSpace::Local,
            XRReferenceSpaceType::Viewer => webxr_api::BaseSpace::Viewer,
            XRReferenceSpaceType::Local_floor => webxr_api::BaseSpace::Floor,
            XRReferenceSpaceType::Bounded_floor => webxr_api::BaseSpace::BoundedFloor,
            _ => panic!("unsupported reference space found"),
        };
        let offset = self.offset.transform();
        Space { base, offset }
    }

    pub fn ty(&self) -> XRReferenceSpaceType {
        self.ty
    }
}

impl XRReferenceSpaceMethods<crate::DomTypeHolder> for XRReferenceSpace {
    /// <https://immersive-web.github.io/webxr/#dom-xrreferencespace-getoffsetreferencespace>
    fn GetOffsetReferenceSpace(&self, new: &XRRigidTransform, can_gc: CanGc) -> DomRoot<Self> {
        let offset = new.transform().then(&self.offset.transform());
        let offset = XRRigidTransform::new(&self.global(), offset, can_gc);
        Self::new_offset(
            &self.global(),
            self.upcast::<XRSpace>().session(),
            self.ty,
            &offset,
        )
    }

    // https://www.w3.org/TR/webxr/#dom-xrreferencespace-onreset
    event_handler!(reset, GetOnreset, SetOnreset);
}

impl XRReferenceSpace {
    /// Get a transform that can be used to locate the base space
    ///
    /// This is equivalent to `get_pose(self).inverse()` (in column vector notation),
    /// but with better types
    pub fn get_base_transform(&self, base_pose: &Frame) -> Option<BaseTransform> {
        let pose = self.get_pose(base_pose)?;
        Some(pose.inverse().cast_unit())
    }

    /// Gets pose represented by this space
    ///
    /// The reference origin used is common between all
    /// get_pose calls for spaces from the same device, so this can be used to compare
    /// with other spaces
    pub fn get_pose(&self, base_pose: &Frame) -> Option<ApiPose> {
        let pose = self.get_unoffset_pose(base_pose)?;
        let offset = self.offset.transform();
        // pose is a transform from the unoffset space to native space,
        // offset is a transform from offset space to unoffset space,
        // we want a transform from unoffset space to native space,
        // which is pose * offset in column vector notation
        Some(offset.then(&pose))
    }

    /// Gets pose represented by this space
    ///
    /// Does not apply originOffset, use get_viewer_pose instead if you need it
    pub fn get_unoffset_pose(&self, base_pose: &Frame) -> Option<ApiPose> {
        match self.ty {
            XRReferenceSpaceType::Local => {
                // The eye-level pose is basically whatever the headset pose was at t=0, which
                // for most devices is (0, 0, 0)
                Some(RigidTransform3D::identity())
            },
            XRReferenceSpaceType::Local_floor | XRReferenceSpaceType::Bounded_floor => {
                let native_to_floor = self
                    .upcast::<XRSpace>()
                    .session()
                    .with_session(|s| s.floor_transform())?;
                Some(cast_transform(native_to_floor.inverse()))
            },
            XRReferenceSpaceType::Viewer => {
                Some(cast_transform(base_pose.pose.as_ref()?.transform))
            },
            _ => unimplemented!(),
        }
    }

    pub fn get_bounds(&self) -> Option<Vec<Point2D<f32, Floor>>> {
        self.upcast::<XRSpace>()
            .session()
            .with_session(|s| s.reference_space_bounds())
    }
}