use crate::graphemes::{nth_next_grapheme_boundary, nth_prev_grapheme_boundary, RopeGraphemes}; use crate::{Position, Range, Rope, RopeSlice, Selection, Syntax}; use anyhow::Error; use std::path::PathBuf; #[derive(Copy, Clone)] pub enum Mode { Normal, Insert, } /// A state represents the current editor state of a single buffer. pub struct State { // TODO: fields should be private but we need to refactor commands.rs first /// Path to file on disk. pub path: Option, pub doc: Rope, pub selection: Selection, pub mode: Mode, // pub syntax: Option, } #[derive(Copy, Clone, PartialEq, Eq)] pub enum Direction { Forward, Backward, } #[derive(Copy, Clone, PartialEq, Eq)] pub enum Granularity { Character, Word, Line, // LineBoundary } impl State { #[must_use] pub fn new(doc: Rope) -> Self { Self { path: None, doc, selection: Selection::single(0, 0), mode: Mode::Normal, syntax: None, } } pub fn load(path: PathBuf) -> Result { use std::{env, fs::File, io::BufReader, path::PathBuf}; let _current_dir = env::current_dir()?; let doc = Rope::from_reader(BufReader::new(File::open(path.clone())?))?; // TODO: create if not found let mut state = Self::new(doc); state.path = Some(path); let language = helix_syntax::get_language(&helix_syntax::LANG::Rust); let mut highlight_config = crate::syntax::HighlightConfiguration::new( language, &std::fs::read_to_string( "../helix-syntax/languages/tree-sitter-rust/queries/highlights.scm", ) .unwrap(), &std::fs::read_to_string( "../helix-syntax/languages/tree-sitter-rust/queries/injections.scm", ) .unwrap(), "", // locals.scm ) .unwrap(); // TODO: config.configure(scopes) is now delayed, is that ok? // TODO: get_language is called twice let syntax = Syntax::new(helix_syntax::LANG::Rust, &state.doc, highlight_config); state.syntax = Some(syntax); Ok(state) } // TODO: doc/selection accessors // TODO: be able to take either Rope or RopeSlice #[inline] pub fn doc(&self) -> &Rope { &self.doc } #[inline] pub fn selection(&self) -> &Selection { &self.selection } #[inline] pub fn mode(&self) -> Mode { self.mode } #[inline] pub fn path(&self) -> Option<&PathBuf> { self.path.as_ref() } // pub fn doc(&self, range: R) -> RopeSlice // where // R: std::ops::RangeBounds, // { // self.doc.slice(range) // } // update/transact: // update(desc) => transaction ? transaction.doc() for applied doc // transaction.apply(doc) // doc.transact(fn -> ... end) // replaceSelection (transaction that replaces selection) // changeByRange // changes // slice // // getters: // tabSize // indentUnit // languageDataAt() // // config: // indentation // tabSize // lineUnit // syntax // foldable // changeFilter/transactionFilter // TODO: move that accepts a boundary matcher fn/list, we keep incrementing until we hit // a boundary // TODO: edits, does each keypress trigger a full command? I guess it's adding to the same // transaction // There should be three pieces of the state: current transaction, the original doc, "preview" // of the new state. // 1. apply the newly generated keypress as a transaction // 2. compose onto a ongoing transaction // 3. on insert mode leave, that transaction gets stored into undo history pub fn move_pos( &self, pos: usize, dir: Direction, granularity: Granularity, count: usize, ) -> usize { let text = &self.doc; match (dir, granularity) { // TODO: clamp movement to line, prevent moving onto \n at the end (Direction::Backward, Granularity::Character) => { nth_prev_grapheme_boundary(&text.slice(..), pos, count) } (Direction::Forward, Granularity::Character) => { nth_next_grapheme_boundary(&text.slice(..), pos, count) } (_, Granularity::Line) => move_vertically(&text.slice(..), dir, pos, count), _ => pos, } } pub fn move_selection( &self, dir: Direction, granularity: Granularity, count: usize, ) -> Selection { // TODO: move all selections according to normal cursor move semantics by collapsing it // into cursors and moving them vertically self.selection.transform(|range| { // let pos = if !range.is_empty() { // // if selection already exists, bump it to the start or end of current select first // if dir == Direction::Backward { // range.from() // } else { // range.to() // } // } else { let pos = self.move_pos(range.head, dir, granularity, count); // }; Range::new(pos, pos) }) } pub fn extend_selection( &self, dir: Direction, granularity: Granularity, count: usize, ) -> Selection { self.selection.transform(|range| { let pos = self.move_pos(range.head, dir, granularity, count); Range::new(range.anchor, pos) }) } } /// Coordinates are a 0-indexed line and column pair. pub type Coords = (usize, usize); // line, col /// Convert a character index to (line, column) coordinates. pub fn coords_at_pos(text: &RopeSlice, pos: usize) -> Position { let line = text.char_to_line(pos); let line_start = text.line_to_char(line); let col = text.slice(line_start..pos).len_chars(); Position::new(line, col) } /// Convert (line, column) coordinates to a character index. pub fn pos_at_coords(text: &RopeSlice, coords: Position) -> usize { let Position { row, col } = coords; let line_start = text.line_to_char(row); nth_next_grapheme_boundary(text, line_start, col) } fn move_vertically(text: &RopeSlice, dir: Direction, pos: usize, count: usize) -> usize { let Position { row, col } = coords_at_pos(text, pos); let new_line = match dir { Direction::Backward => row.saturating_sub(count), Direction::Forward => std::cmp::min(row.saturating_add(count), text.len_lines() - 1), }; // convert to 0-indexed, subtract another 1 because len_chars() counts \n let new_line_len = text.line(new_line).len_chars().saturating_sub(2); let new_col = if new_line_len < col { // TODO: preserve horiz here new_line_len } else { col }; pos_at_coords(text, Position::new(new_line, new_col)) } #[cfg(test)] mod test { use super::*; #[test] fn test_coords_at_pos() { let text = Rope::from("ḧëḷḷö\nẅöṛḷḋ"); assert_eq!(coords_at_pos(&text.slice(..), 0), (0, 0).into()); assert_eq!(coords_at_pos(&text.slice(..), 5), (0, 5).into()); // position on \n assert_eq!(coords_at_pos(&text.slice(..), 6), (1, 0).into()); // position on w assert_eq!(coords_at_pos(&text.slice(..), 7), (1, 1).into()); // position on o assert_eq!(coords_at_pos(&text.slice(..), 10), (1, 4).into()); // position on d } #[test] fn test_pos_at_coords() { let text = Rope::from("ḧëḷḷö\nẅöṛḷḋ"); assert_eq!(pos_at_coords(&text.slice(..), (0, 0).into()), 0); assert_eq!(pos_at_coords(&text.slice(..), (0, 5).into()), 5); // position on \n assert_eq!(pos_at_coords(&text.slice(..), (1, 0).into()), 6); // position on w assert_eq!(pos_at_coords(&text.slice(..), (1, 1).into()), 7); // position on o assert_eq!(pos_at_coords(&text.slice(..), (1, 4).into()), 10); // position on d } #[test] fn test_vertical_move() { let text = Rope::from("abcd\nefg\nwrs"); let pos = pos_at_coords(&text.slice(..), (0, 4).into()); let slice = text.slice(..); assert_eq!( coords_at_pos(&slice, move_vertically(&slice, Direction::Forward, pos, 1)), (1, 2).into() ); } }