From 872253edc2f1f69917d901bb2a812755fd08f8c0 Mon Sep 17 00:00:00 2001
From: Timothy Warren <twarren@nabancard.com>
Date: Mon, 15 Mar 2021 14:53:08 -0400
Subject: [PATCH] Highlight search results

---
 src/document.rs     | 20 +++++++++++++-------
 src/editor.rs       |  4 ++++
 src/highlighting.rs |  2 ++
 src/row.rs          | 36 +++++++++++++++++++++++++++++++++---
 4 files changed, 52 insertions(+), 10 deletions(-)

diff --git a/src/document.rs b/src/document.rs
index 5686848..3390f8f 100644
--- a/src/document.rs
+++ b/src/document.rs
@@ -19,7 +19,7 @@ impl Document {
 
         for value in contents.lines() {
             let mut row = Row::from(value);
-            row.highlight();
+            row.highlight(None);
             rows.push(row);
         }
 
@@ -58,13 +58,13 @@ impl Document {
         if at.y == self.rows.len() {
             let mut row = Row::default();
             row.insert(0, c);
-            row.highlight();
+            row.highlight(None);
             self.rows.push(row);
         } else {
             #[allow(clippy::indexing_slicing)]
             let row = &mut self.rows[at.y];
             row.insert(at.x, c);
-            row.highlight();
+            row.highlight(None);
         }
     }
 
@@ -82,11 +82,11 @@ impl Document {
             let next_row = self.rows.remove(at.y + 1);
             let row = &mut self.rows[at.y];
             row.append(&next_row);
-            row.highlight();
+            row.highlight(None);
         } else {
             let row = &mut self.rows[at.y];
             row.delete(at.x);
-            row.highlight();
+            row.highlight(None);
         }
     }
 
@@ -106,6 +106,12 @@ impl Document {
         Ok(())
     }
 
+    pub fn highlight(&mut self, word: Option<&str>) {
+        for row in &mut self.rows {
+            row.highlight(word);
+        }
+    }
+
     pub fn is_dirty(&self) -> bool {
         self.dirty
     }
@@ -159,8 +165,8 @@ impl Document {
         let current_row = &mut self.rows[at.y];
         let mut new_row = current_row.split(at.x);
 
-        current_row.highlight();
-        new_row.highlight();
+        current_row.highlight(None);
+        new_row.highlight(None);
 
         #[allow(clippy::integer_arithmetic)]
         self.rows.insert(at.y + 1, new_row);
diff --git a/src/editor.rs b/src/editor.rs
index a7ab8fd..6e55326 100644
--- a/src/editor.rs
+++ b/src/editor.rs
@@ -215,6 +215,8 @@ impl Editor {
                     } else if moved {
                         editor.move_cursor(Key::Left);
                     }
+
+                    editor.document.highlight(Some(query));
                 },
             )
             .unwrap_or(None);
@@ -223,6 +225,8 @@ impl Editor {
             self.cursor_position = old_position;
             self.scroll();
         }
+
+        self.document.highlight(None);
     }
 
     fn process_keypress(&mut self) -> Result<(), std::io::Error> {
diff --git a/src/highlighting.rs b/src/highlighting.rs
index e7255e4..b0e3d31 100644
--- a/src/highlighting.rs
+++ b/src/highlighting.rs
@@ -4,12 +4,14 @@ use termion::color;
 pub enum Type {
     None,
     Number,
+    Match,
 }
 
 impl Type {
     pub fn to_color(&self) -> impl color::Color {
         match self {
             Type::Number => color::Rgb(220, 163, 163),
+            Type::Match => color::Rgb(38, 139, 210),
             _ => color::Rgb(255, 255, 255),
         }
     }
diff --git a/src/row.rs b/src/row.rs
index 9ecc186..b71099c 100644
--- a/src/row.rs
+++ b/src/row.rs
@@ -155,7 +155,7 @@ impl Row {
     }
 
     pub fn find(&self, query: &str, at: usize, direction: SearchDirection) -> Option<usize> {
-        if at > self.len {
+        if at > self.len || query.is_empty() {
             return None;
         }
 
@@ -189,15 +189,45 @@ impl Row {
         None
     }
 
-    pub fn highlight(&mut self) {
+    pub fn highlight(&mut self, word: Option<&str>) {
         let mut highlighting = Vec::new();
+        let chars: Vec<char> = self.string.chars().collect();
+        let mut matches = Vec::new();
+        let mut search_index = 0;
+
+        if let Some(word) = word {
+            while let Some(search_match) = self.find(word, search_index, SearchDirection::Forward) {
+                matches.push(search_match);
+
+                if let Some(next_index) = search_match.checked_add(word[..].graphemes(true).count())
+                {
+                    search_index = next_index
+                } else {
+                    break;
+                }
+            }
+        }
+
+        let mut index = 0;
+        while let Some(c) = chars.get(index) {
+            if let Some(word) = word {
+                if matches.contains(&index) {
+                    for _ in word[..].graphemes(true) {
+                        index += 1;
+                        highlighting.push(highlighting::Type::Match);
+                    }
+
+                    continue;
+                }
+            }
 
-        for c in self.string.chars() {
             if c.is_ascii_digit() {
                 highlighting.push(highlighting::Type::Number)
             } else {
                 highlighting.push(highlighting::Type::None)
             }
+
+            index += 1;
         }
 
         self.highlighting = highlighting;