v/examples/term.ui/text_editor.v

584 lines
12 KiB
V

// Copyright (c) 2020 Lars Pontoppidan. All rights reserved.
// Use of this source code is governed by the MIT license distributed with this software.
// Don't use this editor for any serious work.
// A lot of funtionality is missing compared to your favourite editor :)
import strings
import os
import math
import term.ui as tui
enum Movement {
up
down
left
right
home
end
page_up
page_down
}
struct View {
pub:
raw string
cursor Cursor
}
struct App {
mut:
tui &tui.Context = 0
ed &Buffer = 0
current_file int
files []string
status string
t int
magnet_x int
footer_height int = 2
viewport int
}
fn (mut a App) set_status(msg string, duration_ms int) {
a.status = msg
a.t = duration_ms
}
fn (mut a App) save() {
if a.cfile().len > 0 {
b := a.ed
os.write_file(a.cfile(), b.raw()) or { panic(err) }
a.set_status('Saved', 2000)
} else {
a.set_status('No file loaded', 4000)
}
}
fn (mut a App) cfile() string {
if a.files.len == 0 {
return ''
}
if a.current_file >= a.files.len {
return ''
}
return a.files[a.current_file]
}
fn (mut a App) visit_prev_file() {
if a.files.len == 0 {
a.current_file = 0
} else {
a.current_file = (a.current_file + a.files.len - 1) % a.files.len
}
a.init_file()
}
fn (mut a App) visit_next_file() {
if a.files.len == 0 {
a.current_file = 0
} else {
a.current_file = (a.current_file + a.files.len + 1) % a.files.len
}
a.init_file()
}
fn (mut a App) footer() {
w, h := a.tui.window_width, a.tui.window_height
mut b := a.ed
// flat := b.flat()
// snip := if flat.len > 19 { flat[..20] } else { flat }
finfo := if a.cfile().len > 0 { ' (' + os.file_name(a.cfile()) + ')' } else { '' }
mut status := a.status
a.tui.draw_text(0, h - 1, ''.repeat(w))
footer := '$finfo Line ${b.cursor.pos_y + 1:4}/${b.lines.len:-4}, Column ${b.cursor.pos_x + 1:3}/${b.cur_line().len:-3} index: ${b.cursor_index():5} (ESC = quit, Ctrl+s = save)'
if footer.len < w {
a.tui.draw_text((w - footer.len) / 2, h, footer)
} else if footer.len == w {
a.tui.draw_text(0, h, footer)
} else {
a.tui.draw_text(0, h, footer[..w])
}
if a.t <= 0 {
status = ''
} else {
a.tui.set_bg_color(
r: 200
g: 200
b: 200
)
a.tui.set_color(
r: 0
g: 0
b: 0
)
a.tui.draw_text((w + 4 - status.len) / 2, h - 1, ' $status ')
a.tui.reset()
a.t -= 33
}
}
struct Buffer {
tab_width int = 4
pub mut:
lines []string
cursor Cursor
}
fn (b Buffer) flat() string {
return b.raw().replace_each(['\n', r'\n', '\t', r'\t'])
}
fn (b Buffer) raw() string {
return b.lines.join('\n')
}
fn (b Buffer) view(from int, to int) View {
l := b.cur_line()
mut x := 0
for i := 0; i < b.cursor.pos_x && i < l.len; i++ {
if l[i] == `\t` {
x += b.tab_width
continue
}
x++
}
mut lines := []string{}
for i, line in b.lines {
if i >= from && i <= to {
lines << line
}
}
raw := lines.join('\n')
return View{
raw: raw.replace('\t', strings.repeat(` `, b.tab_width))
cursor: Cursor{
pos_x: x
pos_y: b.cursor.pos_y
}
}
}
fn (b Buffer) line(i int) string {
if i < 0 || i >= b.lines.len {
return ''
}
return b.lines[i]
}
fn (b Buffer) cur_line() string {
return b.line(b.cursor.pos_y)
}
fn (b Buffer) cursor_index() int {
mut i := 0
for y, line in b.lines {
if b.cursor.pos_y == y {
i += b.cursor.pos_x
break
}
i += line.len + 1
}
return i
}
fn (mut b Buffer) put(s string) {
has_line_ending := s.contains('\n')
x, y := b.cursor.xy()
if b.lines.len == 0 {
b.lines.prepend('')
}
line := b.lines[y]
l, r := line[..x], line[x..]
if has_line_ending {
mut lines := s.split('\n')
lines[0] = l + lines[0]
lines[lines.len - 1] += r
b.lines.delete(y)
b.lines.insert(y, lines)
last := lines[lines.len - 1]
b.cursor.set(last.len, y + lines.len - 1)
if s == '\n' {
b.cursor.set(0, b.cursor.pos_y)
}
} else {
b.lines[y] = l + s + r
b.cursor.set(x + s.len, y)
}
$if debug {
flat := s.replace('\n', r'\n')
eprintln(@MOD + '.' + @STRUCT + '::' + @FN + ' "$flat"')
}
}
fn (mut b Buffer) del(amount int) string {
if amount == 0 {
return ''
}
x, y := b.cursor.xy()
if amount < 0 { // don't delete left if we're at 0,0
if x == 0 && y == 0 {
return ''
}
} else if x >= b.cur_line().len && y >= b.lines.len - 1 {
return ''
}
mut removed := ''
if amount < 0 { // backspace (backward)
i := b.cursor_index()
removed = b.raw()[i + amount..i]
mut left := amount * -1
for li := y; li >= 0 && left > 0; li-- {
ln := b.lines[li]
if left > ln.len {
b.lines.delete(li)
if ln.len == 0 { // line break delimiter
left--
if y == 0 {
return ''
}
line_above := b.lines[li - 1]
b.cursor.pos_x = line_above.len
} else {
left -= ln.len
}
b.cursor.pos_y--
} else {
if x == 0 {
if y == 0 {
return ''
}
line_above := b.lines[li - 1]
if ln.len == 0 { // at line break
b.lines.delete(li)
b.cursor.pos_y--
b.cursor.pos_x = line_above.len
} else {
b.lines[li - 1] = line_above + ln
b.lines.delete(li)
b.cursor.pos_y--
b.cursor.pos_x = line_above.len
}
} else if x == 1 {
b.lines[li] = b.lines[li][left..]
b.cursor.pos_x = 0
} else {
b.lines[li] = ln[..x - left] + ln[x..]
b.cursor.pos_x -= left
}
left = 0
break
}
}
} else { // delete (forward)
i := b.cursor_index() + 1
removed = b.raw()[i - amount..i]
mut left := amount
for li := y; li >= 0 && left > 0; li++ {
ln := b.lines[li]
if x == ln.len { // at line end
if y + 1 <= b.lines.len {
b.lines[li] = ln + b.lines[y + 1]
b.lines.delete(y + 1)
left--
b.del(left)
}
} else if left > ln.len {
b.lines.delete(li)
left -= ln.len
} else {
b.lines[li] = ln[..x] + ln[x + left..]
left = 0
}
}
}
$if debug {
flat := removed.replace('\n', r'\n')
eprintln(@MOD + '.' + @STRUCT + '::' + @FN + ' "$flat"')
}
return removed
}
fn (mut b Buffer) free() {
$if debug {
eprintln(@MOD + '.' + @STRUCT + '::' + @FN)
}
for line in b.lines {
unsafe { line.free() }
}
unsafe { b.lines.free() }
}
fn (mut b Buffer) move_updown(amount int) {
b.cursor.move(0, amount)
// Check the move
line := b.cur_line()
if b.cursor.pos_x > line.len {
b.cursor.set(line.len, b.cursor.pos_y)
}
}
// move_cursor will navigate the cursor within the buffer bounds
fn (mut b Buffer) move_cursor(amount int, movement Movement) {
cur_line := b.cur_line()
match movement {
.up {
if b.cursor.pos_y - amount >= 0 {
b.move_updown(-amount)
}
}
.down {
if b.cursor.pos_y + amount < b.lines.len {
b.move_updown(amount)
}
}
.page_up {
dlines := math.min(b.cursor.pos_y, amount)
b.move_updown(-dlines)
}
.page_down {
dlines := math.min(b.lines.len - 1, b.cursor.pos_y + amount) - b.cursor.pos_y
b.move_updown(dlines)
}
.left {
if b.cursor.pos_x - amount >= 0 {
b.cursor.move(-amount, 0)
} else if b.cursor.pos_y > 0 {
b.cursor.set(b.line(b.cursor.pos_y - 1).len, b.cursor.pos_y - 1)
}
}
.right {
if b.cursor.pos_x + amount <= cur_line.len {
b.cursor.move(amount, 0)
} else if b.cursor.pos_y + 1 < b.lines.len {
b.cursor.set(0, b.cursor.pos_y + 1)
}
}
.home {
b.cursor.set(0, b.cursor.pos_y)
}
.end {
b.cursor.set(cur_line.len, b.cursor.pos_y)
}
}
}
fn (mut b Buffer) move_to_word(movement Movement) {
a := if movement == .left { -1 } else { 1 }
mut line := b.cur_line()
mut x, mut y := b.cursor.pos_x, b.cursor.pos_y
if x + a < 0 && y > 0 {
y--
line = b.line(b.cursor.pos_y - 1)
x = line.len
} else if x + a >= line.len && y + 1 < b.lines.len {
y++
line = b.line(b.cursor.pos_y + 1)
x = 0
}
// first, move past all non-`a-zA-Z0-9_` characters
for x + a >= 0 && x + a < line.len && !(line[x + a].is_letter()
|| line[x + a].is_digit() || line[x + a] == `_`) {
x += a
}
// then, move past all the letters and numbers
for x + a >= 0 && x + a < line.len && (line[x + a].is_letter()
|| line[x + a].is_digit() || line[x + a] == `_`) {
x += a
}
// if the cursor is out of bounds, move it to the next/previous line
if x + a >= 0 && x + a <= line.len {
x += a
} else if a < 0 && y + 1 > b.lines.len && y - 1 >= 0 {
y += a
x = 0
}
b.cursor.set(x, y)
}
struct Cursor {
pub mut:
pos_x int
pos_y int
}
fn (mut c Cursor) set(x int, y int) {
c.pos_x = x
c.pos_y = y
}
fn (mut c Cursor) move(x int, y int) {
c.pos_x += x
c.pos_y += y
}
fn (c Cursor) xy() (int, int) {
return c.pos_x, c.pos_y
}
// App callbacks
fn init(x voidptr) {
mut a := &App(x)
a.init_file()
}
fn (mut a App) init_file() {
a.ed = &Buffer{}
mut init_y := 0
mut init_x := 0
if a.files.len > 0 && a.current_file < a.files.len && a.files[a.current_file].len > 0 {
if !os.is_file(a.files[a.current_file]) && a.files[a.current_file].contains(':') {
// support the file:line:col: format
fparts := a.files[a.current_file].split(':')
if fparts.len > 0 {
a.files[a.current_file] = fparts[0]
}
if fparts.len > 1 {
init_y = fparts[1].int() - 1
}
if fparts.len > 2 {
init_x = fparts[2].int() - 1
}
}
if os.is_file(a.files[a.current_file]) {
// 'vico: ' +
a.tui.set_window_title(a.files[a.current_file])
mut b := a.ed
content := os.read_file(a.files[a.current_file]) or { panic(err) }
b.put(content)
a.ed.cursor.pos_x = init_x
a.ed.cursor.pos_y = init_y
}
}
}
fn (a &App) view_height() int {
return a.tui.window_height - a.footer_height - 1
}
// magnet_cursor_x will place the cursor as close to it's last move left or right as possible
fn (mut a App) magnet_cursor_x() {
mut buffer := a.ed
if buffer.cursor.pos_x < a.magnet_x {
if a.magnet_x < buffer.cur_line().len {
move_x := a.magnet_x - buffer.cursor.pos_x
buffer.move_cursor(move_x, .right)
}
}
}
fn frame(x voidptr) {
mut a := &App(x)
mut ed := a.ed
a.tui.clear()
scroll_limit := a.view_height()
// scroll down
if ed.cursor.pos_y > a.viewport + scroll_limit { // scroll down
a.viewport = ed.cursor.pos_y - scroll_limit
} else if ed.cursor.pos_y < a.viewport { // scroll up
a.viewport = ed.cursor.pos_y
}
view := ed.view(a.viewport, scroll_limit + a.viewport)
a.tui.draw_text(0, 0, view.raw)
a.footer()
a.tui.set_cursor_position(view.cursor.pos_x + 1, ed.cursor.pos_y + 1 - a.viewport)
a.tui.flush()
}
fn event(e &tui.Event, x voidptr) {
mut a := &App(x)
mut buffer := a.ed
if e.typ == .key_down {
match e.code {
.escape {
exit(0)
}
.enter {
buffer.put('\n')
}
.backspace {
buffer.del(-1)
}
.delete {
buffer.del(1)
}
.left {
if e.modifiers == .ctrl {
buffer.move_to_word(.left)
} else if e.modifiers.is_empty() {
buffer.move_cursor(1, .left)
}
a.magnet_x = buffer.cursor.pos_x
}
.right {
if e.modifiers == .ctrl {
buffer.move_to_word(.right)
} else if e.modifiers.is_empty() {
buffer.move_cursor(1, .right)
}
a.magnet_x = buffer.cursor.pos_x
}
.up {
buffer.move_cursor(1, .up)
a.magnet_cursor_x()
}
.down {
buffer.move_cursor(1, .down)
a.magnet_cursor_x()
}
.page_up {
buffer.move_cursor(a.view_height(), .page_up)
}
.page_down {
buffer.move_cursor(a.view_height(), .page_down)
}
.home {
buffer.move_cursor(1, .home)
}
.end {
buffer.move_cursor(1, .end)
}
48...57, 97...122 { // 0-9a-zA-Z
if e.modifiers == .ctrl {
if e.code == .s {
a.save()
}
} else if !(e.modifiers.has(.ctrl | .alt) || e.code == .null) {
buffer.put(e.ascii.ascii_str())
}
}
else {
if e.modifiers == .alt {
if e.code == .comma {
a.visit_prev_file()
return
}
if e.code == .period {
a.visit_next_file()
return
}
}
buffer.put(e.utf8.bytes().bytestr())
}
}
} else if e.typ == .mouse_scroll {
direction := if e.direction == .up { Movement.down } else { Movement.up }
buffer.move_cursor(1, direction)
}
}
fn main() {
mut files := []string{}
if os.args.len > 1 {
files << os.args[1..]
}
mut a := &App{
files: files
}
a.tui = tui.init(
user_data: a
init_fn: init
frame_fn: frame
event_fn: event
capture_events: true
)
a.tui.run() ?
}