-- some constants people might like to tweak
Text_color = {r=0, g=0, b=0}
Cursor_color = {r=1, g=0, b=0}
Focus_stroke_color = {r=1, g=0, b=0} -- what mouse is hovering over
Highlight_color = {r=0.7, g=0.7, b=0.9} -- selected text
Margin_top = 15
Margin_left = 25
Margin_right = 25
edit = {}
-- run in both tests and a real run
function edit.initialize_state(top, left, right, font_height, line_height) -- currently always draws to bottom of screen
local result = {
lines = {{data=''}}, -- array of strings
-- Lines can be too long to fit on screen, in which case they _wrap_ into
-- multiple _screen lines_.
-- rendering wrapped text lines needs some additional short-lived data per line:
-- startpos, the index of data the line starts rendering from, can only be >1 for topmost line on screen
-- starty, the y coord in pixels the line starts rendering from
-- fragments: snippets of rendered love.graphics.Text, guaranteed to not straddle screen lines
-- screen_line_starting_pos: optional array of grapheme indices if it wraps over more than one screen line
line_cache = {},
-- Given wrapping, any potential location for the text cursor can be described in two ways:
-- * schema 1: As a combination of line index and position within a line (in utf8 codepoint units)
-- * schema 2: As a combination of line index, screen line index within the line, and a position within the screen line.
--
-- Most of the time we'll only persist positions in schema 1, translating to
-- schema 2 when that's convenient.
--
-- Make sure these coordinates are never aliased, so that changing one causes
-- action at a distance.
screen_top1 = {line=1, pos=1}, -- position of start of screen line at top of screen
cursor1 = {line=1, pos=1}, -- position of cursor
screen_bottom1 = {line=1, pos=1}, -- position of start of screen line at bottom of screen
selection1 = {},
-- some extra state to compute selection between mouse press and release
old_cursor1 = nil,
old_selection1 = nil,
mousepress_shift = nil,
-- when selecting text, avoid recomputing some state on every single frame
recent_mouse = {},
-- cursor coordinates in pixels
cursor_x = 0,
cursor_y = 0,
font_height = font_height,
line_height = line_height,
em = App.newText(love.graphics.getFont(), 'm'), -- widest possible character width
top = top,
left = left,
right = right,
width = right-left,
filename = love.filesystem.getUserDirectory()..'/lines.txt', -- '/' should work even on Windows
next_save = nil,
-- undo
history = {},
next_history = 1,
-- search
search_term = nil,
search_text = nil,
search_backup = nil, -- stuff to restore when cancelling search
}
return result
end -- App.initialize_state
function edit.draw(State)
App.color(Text_color)
assert(#State.lines == #State.line_cache)
if not Text.le1(State.screen_top1, State.cursor1) then
print(State.screen_top1.line, State.screen_top1.pos, State.cursor1.line, State.cursor1.pos)
assert(false)
end
State.cursor_x = nil
State.cursor_y = nil
local y = State.top
--? print('== draw')
for line_index = State.screen_top1.line,#State.lines do
local line = State.lines[line_index]
--? print('draw:', y, line_index, line)
if y + State.line_height > App.screen.height then break end
State.screen_bottom1 = {line=line_index, pos=nil}
--? print('text.draw', y, line_index)
local startpos = 1
if line_index == State.screen_top1.line then
startpos = State.screen_top1.pos
end
y, State.screen_bottom1.pos = Text.draw(State, line_index, y, startpos)
y = y + State.line_height
--? print('=> y', y)
end
if State.search_term then
Text.draw_search_bar(State)
end
end
function edit.update(State, dt)
if State.next_save and State.next_save < Current_time then
save_to_disk(State)
State.next_save = nil
end
end
function schedule_save(State)
if State.next_save == nil then
State.next_save = Current_time + 3 -- short enough that you're likely to still remember what you did
end
end
function edit.quit(State)
-- make sure to save before quitting
if State.next_save then
save_to_disk(State)
end
end
function edit.mouse_pressed(State, x,y, mouse_button)
if State.search_term then return end
--? print('press', State.selection1.line, State.selection1.pos)
for line_index,line in ipairs(State.lines) do
if Text.in_line(State, line_index, x,y) then
-- delicate dance between cursor, selection and old cursor/selection
-- scenarios:
-- regular press+release: sets cursor, clears selection
-- shift press+release:
-- sets selection to old cursor if not set otherwise leaves it untouched
-- sets cursor
-- press and hold to start a selection: sets selection on press, cursor on release
-- press and hold, then press shift: ignore shift
-- i.e. mouse_released should never look at shift state
State.old_cursor1 = State.cursor1
State.old_selection1 = State.selection1
State.mousepress_shift = App.shift_down()
State.selection1 = {
line=line_index,
pos=Text.to_pos_on_line(State, line_index, x, y),
}
--? print('selection', State.selection1.line, State.selection1.pos)
break
end
end
end
function edit.mouse_released(State, x,y, mouse_button)
if State.search_term then return end
--? print('release')
for line_index,line in ipairs(State.lines) do
if Text.in_line(State, line_index, x,y) then
--? print('reset selection')
State.cursor1 = {
line=line_index,
pos=Text.to_pos_on_line(State, line_index, x, y),
}
--? print('cursor', State.cursor1.line, State.cursor1.pos)
if State.mousepress_shift then
if State.old_selection1.line == nil then
State.selection1 = State.old_cursor1
else
State.selection1 = State.old_selection1
end
end
State.old_cursor1, State.old_selection1, State.mousepress_shift = nil
if eq(State.cursor1, State.selection1) then
State.selection1 = {}
end
break
end
end
--? print('selection:', State.selection1.line, State.selection1.pos)
end
function edit.textinput(State, t)
for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end -- just in case we scroll
if State.search_term then
State.search_term = State.search_term..t
State.search_text = nil
Text.search_next(State)
else
Text.textinput(State, t)
end
schedule_save(State)
end
function edit.keychord_pressed(State, chord, key)
if State.selection1.line and
-- printable character created using shift key => delete selection
-- (we're not creating any ctrl-shift- or alt-shift- combinations using regular/printable keys)
(not App.shift_down() or utf8.len(key) == 1) and
chord ~= 'C-c' and chord ~= 'C-x' and chord ~= 'backspace' and backspace ~= 'delete' and not App.is_cursor_movement(chord) then
Text.delete_selection(State, State.left, State.right)
end
if State.search_term then
if chord == 'escape' then
State.search_term = nil
State.search_text = nil
State.cursor1 = State.search_backup.cursor
State.screen_top1 = State.search_backup.screen_top
State.search_backup = nil
Text.redraw_all(State) -- if we're scrolling, reclaim all fragments to avoid memory leaks
elseif chord == 'return' then
State.search_term = nil
State.search_text = nil
State.search_backup = nil
elseif chord == 'backspace' then
local len = utf8.len(State.search_term)
local byte_offset = Text.offset(State.search_term, len)
State.search_term = string.sub(State.search_term, 1, byte_offset-1)
State.search_text = nil
elseif chord == 'down' then
State.cursor1.pos = State.cursor1.pos+1
Text.search_next(State)
elseif chord == 'up' then
Text.search_previous(State)
end
return
elseif chord == 'C-f' then
State.search_term = ''
State.search_backup = {
cursor={line=State.cursor1.line, pos=State.cursor1.pos},
screen_top={line=State.screen_top1.line, pos=State.screen_top1.pos},
}
assert(State.search_text == nil)
-- zoom
elseif chord == 'C-=' then
edit.update_font_settings(State, State.font_height+2)
Text.redraw_all(State)
elseif chord == 'C--' then
edit.update_font_settings(State, State.font_height-2)
Text.redraw_all(State)
elseif chord == 'C-0' then
edit.update_font_settings(State, 20)
Text.redraw_all(State)
-- undo
elseif chord == 'C-z' then
for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end -- just in case we scroll
local event = undo_event(State)
if event then
local src = event.before
State.screen_top1 = deepcopy(src.screen_top)
State.cursor1 = deepcopy(src.cursor)
State.selection1 = deepcopy(src.selection)
patch(State.lines, event.after, event.before)
patch_placeholders(State.line_cache, event.after, event.before)
-- if we're scrolling, reclaim all fragments to avoid memory leaks
Text.redraw_all(State)
schedule_save(State)
end
elseif chord == 'C-y' then
for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end -- just in case we scroll
local event = redo_event(State)
if event then
local src = event.after
State.screen_top1 = deepcopy(src.screen_top)
State.cursor1 = deepcopy(src.cursor)
State.selection1 = deepcopy(src.selection)
patch(State.lines, event.before, event.after)
-- if we're scrolling, reclaim all fragments to avoid memory leaks
Text.redraw_all(State)
schedule_save(State)
end
-- clipboard
elseif chord == 'C-c' then
local s = Text.selection(State)
if s then
App.setClipboardText(s)
end
elseif chord == 'C-x' then
for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end -- just in case we scroll
local s = Text.cut_selection(State, State.left, State.right)
if s then
App.setClipboardText(s)
end
schedule_save(State)
elseif chord == 'C-v' then
for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end -- just in case we scroll
-- We don't have a good sense of when to scroll, so we'll be conservative
-- and sometimes scroll when we didn't quite need to.
local before_line = State.cursor1.line
local before = snapshot(State, before_line)
local clipboard_data = App.getClipboardText()
for _,code in utf8.codes(clipboard_data) do
local c = utf8.char(code)
if c == '\n' then
Text.insert_return(State)
else
Text.insert_at_cursor(State, c)
end
end
if Text.cursor_out_of_screen(State) then
Text.snap_cursor_to_bottom_of_screen(State, State.left, State.right)
end
schedule_save(State)
record_undo_event(State, {before=before, after=snapshot(State, before_line, State.cursor1.line)})
-- dispatch to text
else
for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end -- just in case we scroll
Text.keychord_pressed(State, chord)
end
end
function edit.key_released(State, key, scancode)
end
function edit.update_font_settings(State, font_height)
State.font_height = font_height
love.graphics.setFont(love.graphics.newFont(Editor_state.font_height))
State.line_height = math.floor(font_height*1.3)
State.em = App.newText(love.graphics.getFont(), 'm')
Text_cache = {}
end
--== some methods for tests
-- Insulate tests from some key globals so I don't have to change the vast
-- majority of tests when they're modified for the real app.
Test_margin_left = 25
Test_margin_right = 0
function edit.initialize_test_state()
-- if you change these values, tests will start failing
return edit.initialize_state(
15, -- top margin
Test_margin_left,
App.screen.width - Test_margin_right,
14, -- font height assuming default LÖVE font
15) -- line height
end
-- all textinput events are also keypresses
-- TODO: handle chords of multiple keys
function edit.run_after_textinput(State, t)
edit.keychord_pressed(State, t)
edit.textinput(State, t)
edit.key_released(State, t)
App.screen.contents = {}
edit.draw(State)
end
-- not all keys are textinput
function edit.run_after_keychord(State, chord)
edit.keychord_pressed(State, chord)
edit.key_released(State, chord)
App.screen.contents = {}
edit.draw(State)
end
function edit.run_after_mouse_click(State, x,y, mouse_button)
App.fake_mouse_press(x,y, mouse_button)
edit.mouse_pressed(State, x,y, mouse_button)
App.fake_mouse_release(x,y, mouse_button)
edit.mouse_released(State, x,y, mouse_button)
App.screen.contents = {}
edit.draw(State)
end
function edit.run_after_mouse_press(State, x,y, mouse_button)
App.fake_mouse_press(x,y, mouse_button)
edit.mouse_pressed(State, x,y, mouse_button)
App.screen.contents = {}
edit.draw(State)
end
function edit.run_after_mouse_release(State, x,y, mouse_button)
App.fake_mouse_release(x,y, mouse_button)
edit.mouse_released(State, x,y, mouse_button)
App.screen.contents = {}
edit.draw(State)
end