source_select.lua

   1 -- helpers for selecting portions of text
   2 -- To keep things simple, we'll ignore the B side when selections start on the
   3 -- A side, and stick to within a single B side selections start in.
   4
   5 -- Return any intersection of the region from State.selection1 to State.cursor1 (or
   6 -- current mouse, if mouse is pressed; or recent mouse if mouse is pressed and
   7 -- currently over a drawing) with the region between {line=line_index, pos=apos}
   8 -- and {line=line_index, pos=bpos}.
   9 -- apos must be less than bpos. However State.selection1 and State.cursor1 can be in any order.
  10 -- Result: positions spos,epos between apos,bpos.
  11 function Text.clip_selection(State, line_index, apos, bpos)
  12   if State.selection1.line == nil then return nil,nil end
  13   -- min,max = sorted(State.selection1,State.cursor1)
  14   local minl,minp = State.selection1.line,State.selection1.pos
  15   local maxl,maxp
  16   if App.mouse_down(1) then
  17     maxl,maxp = Text.mouse_pos(State)
  18   else
  19     maxl,maxp = State.cursor1.line,State.cursor1.pos
  20   end
  21   if Text.lt1({line=maxl, pos=maxp},
  22               {line=minl, pos=minp}) then
  23     minl,maxl = maxl,minl
  24     minp,maxp = maxp,minp
  25   end
  26   -- check if intervals are disjoint
  27   if line_index < minl then return nil,nil end
  28   if line_index > maxl then return nil,nil end
  29   if line_index == minl and bpos <= minp then return nil,nil end
  30   if line_index == maxl and apos >= maxp then return nil,nil end
  31   -- compare bounds more carefully (start inclusive, end exclusive)
  32   local a_ge = Text.le1({line=minl, pos=minp}, {line=line_index, pos=apos})
  33   local b_lt = Text.lt1({line=line_index, pos=bpos}, {line=maxl, pos=maxp})
  34 --?   print(minl,line_index,maxl, '--', minp,apos,bpos,maxp, '--', a_ge,b_lt)
  35   if a_ge and b_lt then
  36     -- fully contained
  37     return apos,bpos
  38   elseif a_ge then
  39     assert(maxl == line_index)
  40     return apos,maxp
  41   elseif b_lt then
  42     assert(minl == line_index)
  43     return minp,bpos
  44   else
  45     assert(minl == maxl and minl == line_index)
  46     return minp,maxp
  47   end
  48 end
  49
  50 -- draw highlight for line corresponding to (lo,hi) given an approximate x,y and pos on the same screen line
  51 -- Creates text objects every time, so use this sparingly.
  52 -- Returns some intermediate computation useful elsewhere.
  53 function Text.draw_highlight(State, line, x,y, pos, lo,hi)
  54   if lo then
  55     local lo_offset = Text.offset(line.data, lo)
  56     local hi_offset = Text.offset(line.data, hi)
  57     local pos_offset = Text.offset(line.data, pos)
  58     local lo_px
  59     if pos == lo then
  60       lo_px = 0
  61     else
  62       local before = line.data:sub(pos_offset, lo_offset-1)
  63       local before_text = App.newText(love.graphics.getFont(), before)
  64       lo_px = App.width(before_text)
  65     end
  66 --?     print(lo,pos,hi, '--', lo_offset,pos_offset,hi_offset, '--', lo_px)
  67     local s = line.data:sub(lo_offset, hi_offset-1)
  68     local text = App.newText(love.graphics.getFont(), s)
  69     local text_width = App.width(text)
  70     App.color(Highlight_color)
  71     love.graphics.rectangle('fill', x+lo_px,y, text_width,State.line_height)
  72     App.color(Text_color)
  73     return lo_px
  74   end
  75 end
  76
  77 -- inefficient for some reason, so don't do it on every frame
  78 function Text.mouse_pos(State)
  79   local time = love.timer.getTime()
  80   if State.recent_mouse.time and State.recent_mouse.time > time-0.1 then
  81     return State.recent_mouse.line, State.recent_mouse.pos
  82   end
  83   State.recent_mouse.time = time
  84   local line,pos = Text.to_pos(State, App.mouse_x(), App.mouse_y())
  85   if line then
  86     State.recent_mouse.line = line
  87     State.recent_mouse.pos = pos
  88   end
  89   return State.recent_mouse.line, State.recent_mouse.pos
  90 end
  91
  92 function Text.to_pos(State, x,y)
  93   for line_index,line in ipairs(State.lines) do
  94     if line.mode == 'text' then
  95       if Text.in_line(State, line_index, x,y) then
  96         return line_index, Text.to_pos_on_line(State, line_index, x,y)
  97       end
  98     end
  99   end
 100 end
 101
 102 function Text.cut_selection(State)
 103   if State.selection1.line == nil then return end
 104   local result = Text.selection(State)
 105   Text.delete_selection(State)
 106   return result
 107 end
 108
 109 function Text.delete_selection(State)
 110   if State.selection1.line == nil then return end
 111   local minl,maxl = minmax(State.selection1.line, State.cursor1.line)
 112   local before = snapshot(State, minl, maxl)
 113   Text.delete_selection_without_undo(State)
 114   record_undo_event(State, {before=before, after=snapshot(State, State.cursor1.line)})
 115 end
 116
 117 function Text.delete_selection_without_undo(State)
 118   if State.selection1.line == nil then return end
 119   -- min,max = sorted(State.selection1,State.cursor1)
 120   local minl,minp = State.selection1.line,State.selection1.pos
 121   local maxl,maxp = State.cursor1.line,State.cursor1.pos
 122   if minl > maxl then
 123     minl,maxl = maxl,minl
 124     minp,maxp = maxp,minp
 125   elseif minl == maxl then
 126     if minp > maxp then
 127       minp,maxp = maxp,minp
 128     end
 129   end
 130   -- update State.cursor1 and State.selection1
 131   State.cursor1.line = minl
 132   State.cursor1.pos = minp
 133   if Text.lt1(State.cursor1, State.screen_top1) then
 134     State.screen_top1.line = State.cursor1.line
 135     State.screen_top1.pos = Text.pos_at_start_of_screen_line(State, State.cursor1)
 136   end
 137   State.selection1 = {}
 138   -- delete everything between min (inclusive) and max (exclusive)
 139   Text.clear_screen_line_cache(State, minl)
 140   local min_offset = Text.offset(State.lines[minl].data, minp)
 141   local max_offset = Text.offset(State.lines[maxl].data, maxp)
 142   if minl == maxl then
 143 --?     print('minl == maxl')
 144     State.lines[minl].data = State.lines[minl].data:sub(1, min_offset-1)..State.lines[minl].data:sub(max_offset)
 145     return
 146   end
 147   assert(minl < maxl)
 148   local rhs = State.lines[maxl].data:sub(max_offset)
 149   for i=maxl,minl+1,-1 do
 150     table.remove(State.lines, i)
 151     table.remove(State.line_cache, i)
 152   end
 153   State.lines[minl].data = State.lines[minl].data:sub(1, min_offset-1)..rhs
 154 end
 155
 156 function Text.selection(State)
 157   if State.selection1.line == nil then return end
 158   -- min,max = sorted(State.selection1,State.cursor1)
 159   local minl,minp = State.selection1.line,State.selection1.pos
 160   local maxl,maxp = State.cursor1.line,State.cursor1.pos
 161   if minl > maxl then
 162     minl,maxl = maxl,minl
 163     minp,maxp = maxp,minp
 164   elseif minl == maxl then
 165     if minp > maxp then
 166       minp,maxp = maxp,minp
 167     end
 168   end
 169   local min_offset = Text.offset(State.lines[minl].data, minp)
 170   local max_offset = Text.offset(State.lines[maxl].data, maxp)
 171   if minl == maxl then
 172     return State.lines[minl].data:sub(min_offset, max_offset-1)
 173   end
 174   assert(minl < maxl)
 175   local result = {State.lines[minl].data:sub(min_offset)}
 176   for i=minl+1,maxl-1 do
 177     if State.lines[i].mode == 'text' then
 178       table.insert(result, State.lines[i].data)
 179     end
 180   end
 181   table.insert(result, State.lines[maxl].data:sub(1, max_offset-1))
 182   return table.concat(result, '\n')
 183 end