deleting

src/action.rs

@@ -1,6 +1,6 @@
 use std::{cmp::min, mem::swap};
 
-use crate::{BYTES_PER_LINE, app::{App, Mode, PartialAction}};
+use crate::{BYTES_PER_LINE, app::{App, Mode, PartialAction}, edit_action::EditAction};
 
 #[derive(Clone, Copy)]
 pub enum Action {
@@ -40,6 +40,8 @@ pub enum Action {
 	
 	ExtendLineBelow,
 	ExtendLineAbove,
+	
+	Delete,
 }
 
 impl App {
@@ -81,6 +83,8 @@ impl App {
 			
 			Action::ExtendLineBelow => self.extend_line_below(),
 			Action::ExtendLineAbove => self.extend_line_above(),
+			
+			Action::Delete => self.delete(),
 		}
 	}
 	
@@ -273,6 +277,15 @@ impl App {
 			self.cursor.tail += BYTES_PER_LINE - 1 - (self.cursor.tail % BYTES_PER_LINE);
 		}
 	}
+	
+	fn delete(&mut self) {
+		self.execute_and_add(
+			EditAction::Delete {
+				cursor: self.cursor,
+				data: self.contents[self.cursor.range()].into()
+			}
+		);
+	}
 }
 
 // helpers

src/app/mod.rs

@@ -1,21 +1,29 @@
 use std::{env, fs::File, io::Read, path::PathBuf, process::exit};
 use crossterm::{event::{self, Event, KeyEvent}, terminal::window_size};
 use ratatui::style::Color;
-
-use crate::{config::Config, cursor::Cursor};
+use crate::{config::Config, cursor::Cursor, edit_action::EditAction};
 
 mod widget;
 
 pub struct App {
 	pub config: Config,
 	pub file_name: String,
+	
 	pub contents: Vec<u8>,
+	
 	pub window_rows: usize,
+	
 	pub scroll_position: usize,
 	pub cursor: Cursor,
+	
 	pub should_quit: bool,
+	
 	pub mode: Mode,
 	pub partial_action: Option<PartialAction>,
+	
+	pub edit_history: Vec<EditAction>,
+	// some index to keep track of where we are? edit_prophecy?
+	
 	pub logs: Vec<String>,
 }
 
@@ -77,14 +85,22 @@ impl App {
 		Self {
 			config: Config::default(),
 			file_name: file_path.file_name().unwrap().to_str().unwrap().to_owned(),
+			
 			contents,
+			
 			// -1 because of the status line
 			window_rows: window_size().unwrap().rows as usize - 1,
+			
 			scroll_position: 0,
 			cursor: Cursor::default(),
+			
 			should_quit: false,
+			
 			mode: Mode::Normal,
 			partial_action: None,
+			
+			edit_history: Vec::new(),
+			
 			logs: Vec::new(),
 		}
 	}

src/app/widget.rs

@@ -361,7 +361,8 @@ mod status_line {
 				Line::from_iter([
 					self.render_mode(),
 					" ".into(),
-					self.render_file_name()
+					self.render_file_name(),
+					self.modified_indicator()
 				])
 			)
 			.bg(Color::ui_grey())
@@ -376,6 +377,14 @@ mod status_line {
 		fn render_file_name(&self) -> Span<'_> {
 			Span::from(&self.file_name)
 		}
+		
+		fn modified_indicator(&self) -> Span<'static> {
+			if self.edit_history.is_empty() {
+				"".into()
+			} else {
+				" [+]".into()
+			}
+		}
 	}
 }
 

src/config.rs

@@ -131,6 +131,8 @@ impl Default for Config {
 					
 					("x".try_into().unwrap(), Action::ExtendLineBelow),
 					("X".try_into().unwrap(), Action::ExtendLineAbove),
+					
+					("d".try_into().unwrap(), Action::Delete),
 				].into()),
 				(Some(PartialAction::Goto), [
 					("j".try_into().unwrap(), Action::GotoLineStart),
@@ -171,6 +173,8 @@ impl Default for Config {
 					
 					("x".try_into().unwrap(), Action::ExtendLineBelow),
 					("X".try_into().unwrap(), Action::ExtendLineAbove),
+					
+					("d".try_into().unwrap(), Action::Delete),
 				].into())
 			].into())
 		].into()

src/cursor.rs

@@ -1,4 +1,6 @@
-#[derive(Debug, Default, PartialEq, Eq)]
+use std::ops::RangeInclusive;
+
+#[derive(Clone, Copy, Default, PartialEq, Eq)]
 pub struct Cursor {
 	pub head: usize,
 	pub tail: usize
@@ -39,6 +41,14 @@ impl Cursor {
 		self.tail = self.tail.clamp(scroll_position, max_row);
 	}
 	
+	pub const fn range(&self) -> RangeInclusive<usize> {
+		if self.head < self.tail {
+			self.head..=self.tail
+		} else {
+			self.tail..=self.head
+		}
+	}
+	
 	pub fn move_to_next_word(&mut self, max: usize) {
 		if self.head == max { return }
 		

src/edit_action.rs

@@ -0,0 +1,29 @@
+use std::cmp::min;
+use crate::{app::App, cursor::Cursor};
+
+pub enum EditAction {
+	Delete {
+		cursor: Cursor,
+		data: Vec<u8>
+	}
+}
+
+impl App {
+	pub fn execute_and_add(&mut self, edit_action: EditAction) {
+		self.execute_edit(&edit_action);
+		self.edit_history.push(edit_action);
+	}
+	
+	fn execute_edit(&mut self, edit_action: &EditAction) {
+		match edit_action {
+			EditAction::Delete { cursor, .. } => self.delete_at(*cursor),
+		}
+	}
+	
+	fn delete_at(&mut self, cursor: Cursor) {
+		self.contents.drain(cursor.range());
+		
+		self.cursor.head = min(cursor.head, cursor.tail);
+		self.cursor.collapse();
+	}
+}

src/main.rs

@@ -10,6 +10,7 @@ mod app;
 mod config;
 mod cursor;
 mod action;
+mod edit_action;
 
 const BYTES_PER_LINE: usize = 0x10;
 const BYTES_PER_CHUNK: usize = 4;