view.love/edit.lua

382 lines
13 KiB
Lua

-- some constants people might like to tweak
Text_color = {r=0, g=0, b=0}
Cursor_color = {r=1, g=0, b=0}
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, 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 the line 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,
-- cursor coordinates in pixels
cursor_x = 0,
cursor_y = 0,
font = font,
font_height = font_height,
line_height = line_height,
top = top,
left = math.floor(left),
right = math.floor(right),
width = right-left,
filename = love.filesystem.getSourceBaseDirectory()..'/lines.txt', -- '/' should work even on Windows
-- search
search_term = nil,
search_backup = nil, -- stuff to restore when cancelling search
}
return result
end -- edit.initialize_state
function edit.check_locs(State)
-- if State is inconsistent (i.e. file changed by some other program),
-- throw away all cursor state entirely
if edit.invalid1(State, State.screen_top1)
or edit.invalid_cursor1(State)
or not Text.le1(State.screen_top1, State.cursor1) then
State.screen_top1 = {line=1, pos=1}
State.cursor1 = {line=1, pos=1}
end
end
function edit.invalid1(State, loc1)
if loc1.line > #State.lines then return true end
local l = State.lines[loc1.line]
if l.mode ~= 'text' then return false end -- pos is irrelevant to validity for a drawing line
return loc1.pos > #State.lines[loc1.line].data
end
-- cursor loc in particular differs from other locs in one way:
-- pos might occur just after end of line
function edit.invalid_cursor1(State)
local cursor1 = State.cursor1
if cursor1.line > #State.lines then return true end
local l = State.lines[cursor1.line]
if l.mode ~= 'text' then return false end -- pos is irrelevant to validity for a drawing line
return cursor1.pos > #State.lines[cursor1.line].data + 1
end
-- return y drawn until
function edit.draw(State)
love.graphics.setFont(State.font)
App.color(Text_color)
assert(#State.lines == #State.line_cache, ('line_cache is out of date; %d elements when it should be %d'):format(#State.line_cache, #State.lines))
assert(Text.le1(State.screen_top1, State.cursor1), ('screen_top (line=%d,pos=%d) is below cursor (line=%d,pos=%d)'):format(State.screen_top1.line, State.screen_top1.pos, State.cursor1.line, State.cursor1.pos))
State.cursor_x = nil
State.cursor_y = nil
local y = State.top
local screen_bottom1 = {line=nil, pos=nil}
--? 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
screen_bottom1.line = line_index
--? print('text.draw', y, line_index)
local startpos = 1
if line_index == State.screen_top1.line then
startpos = State.screen_top1.pos
end
y, screen_bottom1.pos = Text.draw(State, line_index, y, startpos)
--? print('=> y', y)
end
State.screen_bottom1 = screen_bottom1
if State.search_term then
Text.draw_search_bar(State)
end
return y
end
function edit.update(State, dt)
end
function edit.quit(State)
end
function edit.mouse_press(State, x,y, mouse_button)
love.keyboard.setTextInput(true) -- bring up keyboard on touch screen
if State.search_term then return end
State.mouse_down = mouse_button
--? print_and_log(('edit.mouse_press: cursor at %d,%d'):format(State.cursor1.line, State.cursor1.pos))
if y < State.top then
State.old_cursor1 = State.cursor1
State.old_selection1 = State.selection1
State.mousepress_shift = App.shift_down()
State.selection1 = {
line=State.screen_top1.line,
pos=State.screen_top1.pos,
}
return
end
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_release should never look at shift state
--? print_and_log(('edit.mouse_press: in line %d'):format(line_index))
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),
}
return
end
end
-- still here? mouse press is below all screen lines
State.old_cursor1 = State.cursor1
State.old_selection1 = State.selection1
State.mousepress_shift = App.shift_down()
State.selection1 = {
line=State.screen_bottom1.line,
pos=Text.pos_at_end_of_screen_line(State, State.screen_bottom1),
}
end
function edit.mouse_release(State, x,y, mouse_button)
if State.search_term then return end
--? print_and_log(('edit.mouse_release(%d,%d): cursor at %d,%d'):format(x,y, State.cursor1.line, State.cursor1.pos))
State.mouse_down = nil
if y < State.top then
State.cursor1 = {line=State.screen_top1.line, pos=State.screen_top1.pos}
edit.clean_up_mouse_press(State)
return
end
for line_index,line in ipairs(State.lines) do
if Text.in_line(State, line_index, x,y) then
--? print_and_log(('edit.mouse_release: in line %d'):format(line_index))
State.cursor1 = {
line=line_index,
pos=Text.to_pos_on_line(State, line_index, x, y),
}
--? print_and_log(('edit.mouse_release: cursor now %d,%d'):format(State.cursor1.line, State.cursor1.pos))
edit.clean_up_mouse_press(State)
return
end
end
-- still here? mouse release is below all screen lines
State.cursor1.line, State.cursor1.pos = State.screen_bottom1.line, Text.pos_at_end_of_screen_line(State, State.screen_bottom1)
edit.clean_up_mouse_press(State)
--? print_and_log(('edit.mouse_release: finally selection %s,%s cursor %d,%d'):format(tostring(State.selection1.line), tostring(State.selection1.pos), State.cursor1.line, State.cursor1.pos))
end
function edit.clean_up_mouse_press(State)
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
end
function edit.mouse_wheel_move(State, dx,dy)
if dy > 0 then
State.cursor1 = {line=State.screen_top1.line, pos=State.screen_top1.pos}
for i=1,math.floor(dy) do
Text.up(State)
end
elseif dy < 0 then
State.cursor1 = {line=State.screen_bottom1.line, pos=State.screen_bottom1.pos}
for i=1,math.floor(-dy) do
Text.down(State)
end
end
end
function edit.text_input(State, t)
--? print('text input', t)
if State.search_term then
State.search_term = State.search_term..t
Text.search_next(State)
end
end
function edit.keychord_press(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-a' and chord ~= 'C-c' and chord ~= 'C-x' and chord ~= 'backspace' and chord ~= 'delete' and chord ~= 'C-z' and chord ~= 'C-y' and not App.is_cursor_movement(key) then
Text.delete_selection(State, State.left, State.right)
end
if State.search_term then
for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end -- just in case we scroll
if chord == 'escape' then
State.search_term = 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_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)
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},
}
-- zoom
elseif chord == 'C-=' then
edit.update_font_settings(State, State.font_height+2)
Text.redraw_all(State)
elseif chord == 'C--' then
if State.font_height > 2 then
edit.update_font_settings(State, State.font_height-2)
Text.redraw_all(State)
end
elseif chord == 'C-0' then
edit.update_font_settings(State, 20)
Text.redraw_all(State)
-- clipboard
elseif chord == 'C-a' then
State.selection1 = {line=1, pos=1}
State.cursor1 = {line=#State.lines, pos=utf8.len(State.lines[#State.lines].data)+1}
elseif chord == 'C-c' then
local s = Text.selection(State)
if s then
App.set_clipboard(s)
end
-- 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_press(State, chord)
end
end
function edit.key_release(State, key, scancode)
end
function edit.update_font_settings(State, font_height)
State.font_height = font_height
State.font = love.graphics.newFont(State.font_height)
State.line_height = math.floor(font_height*1.3)
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,
love.graphics.getFont(),
14,
15) -- line height
end
-- all text_input events are also keypresses
-- TODO: handle chords of multiple keys
function edit.run_after_text_input(State, t)
edit.keychord_press(State, t)
edit.text_input(State, t)
edit.key_release(State, t)
App.screen.contents = {}
edit.update(State, 0)
edit.draw(State)
end
-- not all keys are text_input
function edit.run_after_keychord(State, chord, key)
edit.keychord_press(State, chord, key)
edit.key_release(State, key)
App.screen.contents = {}
edit.update(State, 0)
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_press(State, x,y, mouse_button)
App.fake_mouse_release(x,y, mouse_button)
edit.mouse_release(State, x,y, mouse_button)
App.screen.contents = {}
edit.update(State, 0)
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_press(State, x,y, mouse_button)
App.screen.contents = {}
edit.update(State, 0)
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_release(State, x,y, mouse_button)
App.screen.contents = {}
edit.update(State, 0)
edit.draw(State)
end