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

use bevy_app::prelude::*;
use bevy_ecs::prelude::*;
use valence_entity::entity::Flags;
use valence_entity::{entity, Pose};
pub use valence_protocol::packets::play::client_command_c2s::ClientCommand;
use valence_protocol::packets::play::ClientCommandC2s;

use crate::event_loop::{EventLoopPreUpdate, PacketEvent};

pub struct ClientCommandPlugin;

impl Plugin for ClientCommandPlugin {
    fn build(&self, app: &mut App) {
        app.add_event::<SprintEvent>()
            .add_event::<SneakEvent>()
            .add_event::<JumpWithHorseEvent>()
            .add_event::<LeaveBedEvent>()
            .add_systems(EventLoopPreUpdate, handle_client_command);
    }
}

#[derive(Event, Copy, Clone, PartialEq, Eq, Debug)]
pub struct SprintEvent {
    pub client: Entity,
    pub state: SprintState,
}

#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum SprintState {
    Start,
    Stop,
}

#[derive(Event, Copy, Clone, PartialEq, Eq, Debug)]
pub struct SneakEvent {
    pub client: Entity,
    pub state: SneakState,
}

#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum SneakState {
    Start,
    Stop,
}

#[derive(Event, Copy, Clone, PartialEq, Eq, Debug)]
pub struct JumpWithHorseEvent {
    pub client: Entity,
    pub state: JumpWithHorseState,
}

#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum JumpWithHorseState {
    Start {
        /// The power of the horse jump in `0..=100`.
        power: u8,
    },
    Stop,
}

#[derive(Event, Copy, Clone, PartialEq, Eq, Debug)]
pub struct LeaveBedEvent {
    pub client: Entity,
}

fn handle_client_command(
    mut packets: EventReader<PacketEvent>,
    mut clients: Query<(&mut entity::Pose, &mut Flags)>,
    mut sprinting_events: EventWriter<SprintEvent>,
    mut sneaking_events: EventWriter<SneakEvent>,
    mut jump_with_horse_events: EventWriter<JumpWithHorseEvent>,
    mut leave_bed_events: EventWriter<LeaveBedEvent>,
) {
    for packet in packets.read() {
        if let Some(pkt) = packet.decode::<ClientCommandC2s>() {
            match pkt.action {
                ClientCommand::StartSneaking => {
                    if let Ok((mut pose, mut flags)) = clients.get_mut(packet.client) {
                        pose.0 = Pose::Sneaking;
                        flags.set_sneaking(true);
                    }

                    sneaking_events.send(SneakEvent {
                        client: packet.client,
                        state: SneakState::Start,
                    });
                }
                ClientCommand::StopSneaking => {
                    if let Ok((mut pose, mut flags)) = clients.get_mut(packet.client) {
                        pose.0 = Pose::Standing;
                        flags.set_sneaking(false);
                    }

                    sneaking_events.send(SneakEvent {
                        client: packet.client,
                        state: SneakState::Stop,
                    });
                }
                ClientCommand::LeaveBed => {
                    leave_bed_events.send(LeaveBedEvent {
                        client: packet.client,
                    });
                }
                ClientCommand::StartSprinting => {
                    if let Ok((_, mut flags)) = clients.get_mut(packet.client) {
                        flags.set_sprinting(true);
                    }

                    sprinting_events.send(SprintEvent {
                        client: packet.client,
                        state: SprintState::Start,
                    });
                }
                ClientCommand::StopSprinting => {
                    if let Ok((_, mut flags)) = clients.get_mut(packet.client) {
                        flags.set_sprinting(false);
                    }

                    sprinting_events.send(SprintEvent {
                        client: packet.client,
                        state: SprintState::Stop,
                    });
                }
                ClientCommand::StartJumpWithHorse => {
                    jump_with_horse_events.send(JumpWithHorseEvent {
                        client: packet.client,
                        state: JumpWithHorseState::Start {
                            power: pkt.jump_boost.0 as u8,
                        },
                    });
                }
                ClientCommand::StopJumpWithHorse => {
                    jump_with_horse_events.send(JumpWithHorseEvent {
                        client: packet.client,
                        state: JumpWithHorseState::Stop,
                    });
                }
                ClientCommand::OpenHorseInventory => {} // TODO
                ClientCommand::StartFlyingWithElytra => {
                    if let Ok((mut pose, _)) = clients.get_mut(packet.client) {
                        pose.0 = Pose::FallFlying;
                    }

                    // TODO.
                }
            }
        }
    }
}