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
use std::{
    rc::Rc,
    sync::{Arc, Mutex},
};

use dioxus_core::{prelude::spawn, use_hook, AttributeValue};
use dioxus_hooks::to_owned;
use dioxus_signals::{Readable, Signal, Writable};
use freya_common::{CursorLayoutResponse, EventMessage};
use freya_elements::events::{KeyboardData, MouseData};
use freya_node_state::{CursorReference, CustomAttributeValues};
use tokio::sync::mpsc::unbounded_channel;
use torin::geometry::CursorPoint;
use uuid::Uuid;

use crate::{use_platform, RopeEditor, TextCursor, TextEditor, TextEvent, UsePlatform};

/// Events emitted to the [`UseEditable`].
pub enum EditableEvent {
    Click,
    MouseOver(Rc<MouseData>, usize),
    MouseDown(Rc<MouseData>, usize),
    KeyDown(Rc<KeyboardData>),
}

/// How the editable content must behave.
#[derive(PartialEq, Eq, Clone, Copy)]
pub enum EditableMode {
    /// Multiple editors of only one line.
    ///
    /// Useful for textarea-like editors that need more customization than a simple paragraph for example.
    SingleLineMultipleEditors,
    /// One editor of multiple lines.
    ///
    /// A paragraph for example.
    MultipleLinesSingleEditor,
}

impl Default for EditableMode {
    fn default() -> Self {
        Self::MultipleLinesSingleEditor
    }
}

/// Manage an editable content.
#[derive(Clone)]
pub struct UseEditable {
    pub(crate) editor: Signal<RopeEditor>,
    pub(crate) cursor_reference: CursorReference,
    pub(crate) selecting_text_with_mouse: Signal<Option<CursorPoint>>,
    pub(crate) platform: UsePlatform,
}

impl UseEditable {
    /// Reference to the editor.
    pub fn editor(&self) -> &Signal<RopeEditor> {
        &self.editor
    }

    /// Mutable reference to the editor.
    pub fn editor_mut(&mut self) -> &mut Signal<RopeEditor> {
        &mut self.editor
    }

    /// Create a cursor attribute.
    pub fn cursor_attr(&self) -> AttributeValue {
        AttributeValue::any_value(CustomAttributeValues::CursorReference(
            self.cursor_reference.clone(),
        ))
    }

    /// Create a highlights attribute.
    pub fn highlights_attr(&self, editor_id: usize) -> AttributeValue {
        AttributeValue::any_value(CustomAttributeValues::TextHighlights(
            self.editor
                .read()
                .highlights(editor_id)
                .map(|v| vec![v])
                .unwrap_or_default(),
        ))
    }

    /// Process a [`EditableEvent`] event.
    pub fn process_event(&mut self, edit_event: &EditableEvent) {
        match edit_event {
            EditableEvent::MouseDown(e, id) => {
                let coords = e.get_element_coordinates();
                *self.selecting_text_with_mouse.write() = Some(coords);

                self.cursor_reference.set_id(Some(*id));
                self.cursor_reference.set_cursor_position(Some(coords));

                self.editor.write().unhighlight();
            }
            EditableEvent::MouseOver(e, id) => {
                self.selecting_text_with_mouse.with(|selecting_text| {
                    if let Some(current_dragging) = selecting_text {
                        let coords = e.get_element_coordinates();

                        self.cursor_reference.set_id(Some(*id));
                        self.cursor_reference
                            .set_cursor_selections(Some((*current_dragging, coords)));
                    }
                });
            }
            EditableEvent::Click => {
                *self.selecting_text_with_mouse.write() = None;
            }
            EditableEvent::KeyDown(e) => {
                let event = self
                    .editor
                    .write()
                    .process_key(&e.key, &e.code, &e.modifiers);
                if event.contains(TextEvent::TEXT_CHANGED) {
                    *self.selecting_text_with_mouse.write() = None;
                }
            }
        }

        if self.selecting_text_with_mouse.peek().is_some() {
            self.platform
                .send(EventMessage::RemeasureTextGroup(
                    self.cursor_reference.text_id,
                ))
                .unwrap()
        }
    }
}

/// Create a configuration for a [`UseEditable`].
pub struct EditableConfig {
    pub(crate) content: String,
    pub(crate) cursor: TextCursor,
}

impl EditableConfig {
    /// Create a [`EditableConfig`].
    pub fn new(content: String) -> Self {
        Self {
            content,
            cursor: TextCursor::default(),
        }
    }

    /// Specify a custom initial cursor positions.
    pub fn with_cursor(mut self, (row, col): (usize, usize)) -> Self {
        self.cursor = TextCursor::new(row, col);
        self
    }
}

/// Create a virtual text editor with it's own cursor and rope.
pub fn use_editable(initializer: impl Fn() -> EditableConfig, mode: EditableMode) -> UseEditable {
    let platform = use_platform();

    use_hook(|| {
        let text_id = Uuid::new_v4();
        let config = initializer();
        let editor = Signal::new(RopeEditor::new(config.content, config.cursor, mode));
        let selecting_text_with_mouse = Signal::new(None);
        let (cursor_sender, mut cursor_receiver) = unbounded_channel::<CursorLayoutResponse>();
        let cursor_reference = CursorReference {
            text_id,
            cursor_sender,
            cursor_position: Arc::new(Mutex::new(None)),
            cursor_id: Arc::new(Mutex::new(None)),
            cursor_selections: Arc::new(Mutex::new(None)),
        };

        spawn({
            to_owned![cursor_reference];
            async move {
                while let Some(message) = cursor_receiver.recv().await {
                    match message {
                        // Update the cursor position calculated by the layout
                        CursorLayoutResponse::CursorPosition { position, id } => {
                            let mut text_editor = editor.write();

                            let new_cursor_row = match mode {
                                EditableMode::MultipleLinesSingleEditor => {
                                    text_editor.char_to_line(position)
                                }
                                EditableMode::SingleLineMultipleEditors => id,
                            };

                            let new_cursor_col = match mode {
                                EditableMode::MultipleLinesSingleEditor => {
                                    position - text_editor.line_to_char(new_cursor_row)
                                }
                                EditableMode::SingleLineMultipleEditors => position,
                            };

                            let new_current_line = text_editor.line(new_cursor_row).unwrap();

                            // Use the line length as new column if the clicked column surpases the length
                            let new_cursor = if new_cursor_col >= new_current_line.len_chars() {
                                (new_current_line.len_chars(), new_cursor_row)
                            } else {
                                (new_cursor_col, new_cursor_row)
                            };

                            // Only update if it's actually different
                            if text_editor.cursor().as_tuple() != new_cursor {
                                text_editor.cursor_mut().set_col(new_cursor.0);
                                text_editor.cursor_mut().set_row(new_cursor.1);
                                text_editor.unhighlight();
                            }

                            // Remove the current calcutions so the layout engine doesn't try to calculate again
                            cursor_reference.set_cursor_position(None);
                        }
                        // Update the text selections calculated by the layout
                        CursorLayoutResponse::TextSelection { from, to, id } => {
                            editor.write().highlight_text(from, to, id);
                            cursor_reference.set_cursor_selections(None);
                        }
                    }
                }
            }
        });

        UseEditable {
            editor,
            cursor_reference: cursor_reference.clone(),
            selecting_text_with_mouse,
            platform,
        }
    })
}