From f8bc1a2ce44e5e6bda41864bb9a714706a992e0c Mon Sep 17 00:00:00 2001
From: Keith Simmons <keith@the-simmons.net>
Date: Thu, 23 Jan 2020 17:47:26 -0800
Subject: [PATCH] emojis working

---
 Cargo.lock                      |  1 +
 Cargo.toml                      |  1 +
 src/editor/mod.rs               | 41 ++++++++++++++++++----------
 src/renderer/caching_shaper.rs  | 47 ++++++++++-----------------------
 src/renderer/cursor_renderer.rs | 20 +++++++++++---
 src/renderer/mod.rs             | 10 +++++--
 6 files changed, 67 insertions(+), 53 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 825affd..f3bcc40 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1485,6 +1485,7 @@ dependencies = [
  "skribo",
  "skulpin",
  "tokio",
+ "unicode-segmentation",
  "winres",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index 563937c..194525b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,6 +21,7 @@ nvim-rs = { git = "https://github.com/KillTheMule/nvim-rs", branch = "futures",
 tokio = { version = "0.2.9", features = [ "blocking", "process", "time" ] }
 async-trait = "0.1.18"
 lazy_static = "1.4.0"
+unicode-segmentation = "1.6.0"
 
 [build-dependencies]
 winres = "0.1.11"
diff --git a/src/editor/mod.rs b/src/editor/mod.rs
index 87ef674..7191194 100644
--- a/src/editor/mod.rs
+++ b/src/editor/mod.rs
@@ -6,6 +6,7 @@ use std::sync::{Arc, Mutex};
 
 use skulpin::skia_safe::colors;
 use skulpin::winit::window::Window;
+use unicode_segmentation::UnicodeSegmentation;
 
 pub use cursor::{Cursor, CursorShape, CursorMode};
 pub use style::{Colors, Style};
@@ -17,7 +18,7 @@ lazy_static! {
     pub static ref EDITOR: Arc<Mutex<Editor>> = Arc::new(Mutex::new(Editor::new()));
 }
 
-pub type GridCell = Option<(char, Option<Style>)>;
+pub type GridCell = Option<(String, Option<Style>)>;
 
 #[derive(new, Debug, Clone)]
 pub struct DrawCommand {
@@ -102,9 +103,9 @@ impl Editor {
                 }
             }
 
-            fn add_character(command: &mut Option<DrawCommand>, character: &char, row_index: u64, col_index: u64, style: Option<Style>) {
+            fn add_character(command: &mut Option<DrawCommand>, character: &str, row_index: u64, col_index: u64, style: Option<Style>) {
                 match command {
-                    Some(command) => command.text.push(character.clone()),
+                    Some(command) => command.text.push_str(character),
                     None => {
                         command.replace(DrawCommand::new(character.to_string(), (col_index, row_index), style));
                     }
@@ -112,12 +113,18 @@ impl Editor {
             }
 
             for (col_index, cell) in row.iter().enumerate() {
-                let (character, style) = cell.clone().unwrap_or_else(|| (' ', Some(Style::new(self.default_colors.clone()))));
-                if !command_matches(&command, &style) {
+                let (character, style) = cell.clone().unwrap_or_else(|| (' '.to_string(), Some(Style::new(self.default_colors.clone()))));
+                if character.is_empty() {
+                    add_character(&mut command, &" ", row_index as u64, col_index as u64, style.clone());
                     add_command(&mut draw_commands, command);
                     command = None;
+                } else {
+                    if !command_matches(&command, &style) {
+                        add_command(&mut draw_commands, command);
+                        command = None;
+                    }
+                    add_character(&mut command, &character, row_index as u64, col_index as u64, style.clone());
                 }
-                add_character(&mut command, &character, row_index as u64, col_index as u64, style.clone());
             }
             add_command(&mut draw_commands, command);
         }
@@ -127,7 +134,7 @@ impl Editor {
             let (x, y) = command.grid_position;
             let dirty_row = &self.dirty[y as usize];
 
-            for char_index in 0..command.text.chars().count() {
+            for char_index in 0..command.text.graphemes(true).count() {
                 if dirty_row[x as usize + char_index] {
                     return true;
                 }
@@ -155,15 +162,21 @@ impl Editor {
 
         let row = self.grid.get_mut(row_index as usize).expect("Grid must have size greater than row_index");
         let dirty_row = &mut self.dirty[row_index as usize];
-        for (i, character) in text.chars().enumerate() {
-            let pointer_index = i + *column_pos as usize;
-            if pointer_index < row.len() {
-                row[pointer_index] = Some((character, style.clone()));
-                dirty_row[pointer_index] = true;
+
+        if text.is_empty() {
+            row[*column_pos as usize] = Some(("".to_string(), style.clone()));
+            dirty_row[*column_pos as usize] = true;
+            *column_pos = *column_pos + 1;
+        } else {
+            for (i, character) in text.graphemes(true).enumerate() {
+                let pointer_index = i + *column_pos as usize;
+                if pointer_index < row.len() {
+                    row[pointer_index] = Some((character.to_string(), style.clone()));
+                    dirty_row[pointer_index] = true;
+                }
             }
+            *column_pos = *column_pos + text.graphemes(true).count() as u64;
         }
-
-        *column_pos = *column_pos + text.chars().count() as u64;
         self.previous_style = style;
     }
 
diff --git a/src/renderer/caching_shaper.rs b/src/renderer/caching_shaper.rs
index 025bfa3..98fb7d3 100644
--- a/src/renderer/caching_shaper.rs
+++ b/src/renderer/caching_shaper.rs
@@ -4,7 +4,7 @@ use std::collections::HashMap;
 use lru::LruCache;
 use skulpin::skia_safe::{TextBlob, Font as SkiaFont, FontStyle, Typeface, TextBlobBuilder};
 use font_kit::source::SystemSource;
-use skribo::{layout, layout_run, FontRef as SkriboFont, FontFamily, FontCollection, TextStyle};
+use skribo::{layout_run, LayoutSession, FontRef as SkriboFont, FontFamily, FontCollection, TextStyle};
 
 const STANDARD_CHARACTER_STRING: &'static str = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
 
@@ -103,39 +103,22 @@ impl CachingShaper {
 
         let style = TextStyle { size: base_size * scale as f32 };
 
-        let mut family = FontFamily::new();
-        family.add_font(font_pair.normal.1.clone());
-        family.add_font(font_pair.emoji.1.clone());
-
         let mut collection = FontCollection::new();
-        collection.add_family(family);
 
-        let layout = layout(&style, &collection, text);
+        let mut normal_family = FontFamily::new();
+        normal_family.add_font(font_pair.normal.1.clone());
+        collection.add_family(normal_family);
 
-        let mut groups = Vec::new();
-        let mut group = Vec::new();
-        let mut previous_font: Option<SkriboFont> = None;
+        let mut emoji_family = FontFamily::new();
+        emoji_family.add_font(font_pair.emoji.1.clone());
+        collection.add_family(emoji_family);
 
-        for glyph in layout.glyphs {
-            if previous_font.clone().map(|previous_font| Arc::ptr_eq(&previous_font.font, &glyph.font.font)).unwrap_or(true) {
-                group.push(glyph);
-            } else {
-                groups.push(group);
-                previous_font = Some(glyph.font.clone());
-                group = vec![glyph];
-            }
-        }
-        if !group.is_empty() {
-            groups.push(group);
-        }
+        let session = LayoutSession::create(text, &style, &collection);
 
         let mut blobs = Vec::new();
-        for group in groups {
-            if group.is_empty() {
-                continue;
-            }
 
-            let skribo_font = group[0].font.clone();
+        for layout_run in session.iter_all() {
+            let skribo_font = layout_run.font();
             let skia_font = if Arc::ptr_eq(&skribo_font.font, &font_pair.normal.1.font) {
                 &font_pair.normal.0
             } else {
@@ -144,16 +127,14 @@ impl CachingShaper {
 
             let mut blob_builder = TextBlobBuilder::new();
 
-            let count = group.len();
+            let count = layout_run.glyphs().count();
             let metrics = skribo_font.font.metrics();
             let ascent = metrics.ascent * base_size / metrics.units_per_em as f32;
             let (glyphs, positions) = blob_builder.alloc_run_pos_h(&skia_font, count, ascent, None);
 
-            for (i, glyph_id) in group.iter().map(|glyph| glyph.glyph_id as u16).enumerate() {
-                glyphs[i] = glyph_id;
-            }
-            for (i, offset) in group.iter().map(|glyph| glyph.offset.x as f32).enumerate() {
-                positions[i] = offset;
+            for (i, glyph) in layout_run.glyphs().enumerate() {
+                glyphs[i] = glyph.glyph_id as u16;
+                positions[i] = glyph.offset.x;
             }
             blobs.push(blob_builder.make().unwrap());
         }
diff --git a/src/renderer/cursor_renderer.rs b/src/renderer/cursor_renderer.rs
index 25a0982..6030ef5 100644
--- a/src/renderer/cursor_renderer.rs
+++ b/src/renderer/cursor_renderer.rs
@@ -195,7 +195,22 @@ impl CursorRenderer {
 
         let (grid_x, grid_y) = self.previous_position;
 
-        let font_dimensions: Point = (font_width, font_height).into();
+        let (character, font_dimensions): (String, Point) = {
+            let editor = EDITOR.lock().unwrap();
+            let character = editor.grid[grid_y as usize][grid_x as usize].clone()
+                .map(|(character, _)| character)
+                .unwrap_or(' '.to_string());
+            let is_double = editor.grid[grid_y as usize]
+                .get(grid_x as usize + 1)
+                .map(|cell| cell.as_ref().map(|(character, _)| character.is_empty()).unwrap_or(false))
+                .unwrap_or(false);
+
+            let font_width = match (is_double, &cursor.shape) {
+                (true, CursorShape::Block) => font_width * 2.0,
+                _ => font_width
+            };
+            (character, (font_width, font_height).into())
+        };
         let destination: Point = (grid_x as f32 * font_width, grid_y as f32 * font_height).into();
         let center_destination = destination + font_dimensions * 0.5;
 
@@ -226,9 +241,6 @@ impl CursorRenderer {
             // Draw foreground
             paint.set_color(cursor.foreground(&default_colors).to_color());
             let editor = EDITOR.lock().unwrap();
-            let character = editor.grid[grid_y as usize][grid_x as usize].clone()
-                .map(|(character, _)| character)
-                .unwrap_or(' ');
             canvas.save();
             canvas.clip_path(&path, None, Some(false));
             
diff --git a/src/renderer/mod.rs b/src/renderer/mod.rs
index 90ebe95..f2a2aab 100644
--- a/src/renderer/mod.rs
+++ b/src/renderer/mod.rs
@@ -3,6 +3,7 @@ use std::time::Instant;
 use skulpin::CoordinateSystemHelper;
 use skulpin::skia_safe::{Canvas, Paint, Surface, Budgeted, Rect, colors};
 use skulpin::skia_safe::gpu::SurfaceOrigin;
+use unicode_segmentation::UnicodeSegmentation;
 
 mod caching_shaper;
 mod cursor_renderer;
@@ -54,7 +55,7 @@ impl Renderer {
         let (grid_x, grid_y) = grid_pos;
         let x = grid_x as f32 * self.font_width;
         let y = grid_y as f32 * self.font_height;
-        let width = text.chars().count() as f32 * self.font_width * size as f32;
+        let width = text.graphemes(true).count() as f32 * self.font_width * size as f32;
         let height = self.font_height * size as f32;
         Rect::new(x, y, x + width, y + height)
     }
@@ -71,13 +72,18 @@ impl Renderer {
         let (grid_x, grid_y) = grid_pos;
         let x = grid_x as f32 * self.font_width;
         let y = grid_y as f32 * self.font_height;
-        let width = text.chars().count() as f32 * self.font_width;
+        let width = text.graphemes(true).count() as f32 * self.font_width;
 
         let style = style.clone().unwrap_or_else(|| Style::new(default_colors.clone()));
 
         canvas.save();
 
         let region = self.compute_text_region(text, grid_pos, size);
+        let region = Rect::new(
+            region.x() - self.font_width, 
+            region.y(), 
+            region.x() + region.width() + self.font_width, 
+            region.y() + region.height());
 
         canvas.clip_rect(region, None, Some(false));