search.lua

   1 -- helpers for the search bar (C-f)
   2
   3 function Text.draw_search_bar(State)
   4   local h = State.line_height+2
   5   local y = App.screen.height-h
   6   love.graphics.setColor(0.9,0.9,0.9)
   7   love.graphics.rectangle('fill', 0, y-10, App.screen.width-1, h+8)
   8   love.graphics.setColor(0.6,0.6,0.6)
   9   love.graphics.line(0, y-10, App.screen.width-1, y-10)
  10   love.graphics.setColor(1,1,1)
  11   love.graphics.rectangle('fill', 20, y-6, App.screen.width-40, h+2, 2,2)
  12   love.graphics.setColor(0.6,0.6,0.6)
  13   love.graphics.rectangle('line', 20, y-6, App.screen.width-40, h+2, 2,2)
  14   App.color(Text_color)
  15   App.screen.print(State.search_term, 25,y-5)
  16   Text.draw_cursor(State, 25+State.font:getWidth(State.search_term),y-5)
  17 end
  18
  19 function Text.search_next(State)
  20   -- search current line from cursor
  21   local curr_pos = State.cursor1.pos
  22   local curr_line = State.lines[State.cursor1.line].data
  23   local curr_offset = Text.offset(curr_line, curr_pos)
  24   local offset = find(curr_line, State.search_term, curr_offset, --[[literal]] true)
  25   if offset then
  26     State.cursor1.pos = utf8.len(curr_line, 1, offset)
  27   end
  28   if offset == nil then
  29     -- search lines below cursor
  30     for i=State.cursor1.line+1,#State.lines do
  31       local curr_line = State.lines[i].data
  32       offset = find(curr_line, State.search_term, --[[from start]] nil, --[[literal]] true)
  33       if offset then
  34         State.cursor1 = {line=i, pos=utf8.len(curr_line, 1, offset)}
  35         break
  36       end
  37     end
  38   end
  39   if offset == nil then
  40     -- wrap around
  41     for i=1,State.cursor1.line-1 do
  42       local curr_line = State.lines[i].data
  43       offset = find(curr_line, State.search_term, --[[from start]] nil, --[[literal]] true)
  44       if offset then
  45         State.cursor1 = {line=i, pos=utf8.len(curr_line, 1, offset)}
  46         break
  47       end
  48     end
  49   end
  50   if offset == nil then
  51     -- search current line until cursor
  52     local curr_line = State.lines[State.cursor1.line].data
  53     offset = find(curr_line, State.search_term, --[[from start]] nil, --[[literal]] true)
  54     local pos = utf8.len(curr_line, 1, offset)
  55     if pos and pos < State.cursor1.pos then
  56       State.cursor1.pos = pos
  57     end
  58   end
  59   if offset == nil then
  60     State.cursor1.line = State.search_backup.cursor.line
  61     State.cursor1.pos = State.search_backup.cursor.pos
  62     State.screen_top1.line = State.search_backup.screen_top.line
  63     State.screen_top1.pos = State.search_backup.screen_top.pos
  64   end
  65   local screen_bottom1 = Text.screen_bottom1(State)
  66   if Text.lt1(State.cursor1, State.screen_top1) or Text.lt1(screen_bottom1, State.cursor1) then
  67     State.screen_top1.line = State.cursor1.line
  68     local pos = Text.pos_at_start_of_screen_line(State, State.cursor1)
  69     State.screen_top1.pos = pos
  70   end
  71 end
  72
  73 function Text.search_previous(State)
  74   -- search current line before cursor
  75   local curr_pos = State.cursor1.pos
  76   local curr_line = State.lines[State.cursor1.line].data
  77   local curr_offset = Text.offset(curr_line, curr_pos)
  78   local offset = rfind(curr_line, State.search_term, curr_offset-1, --[[literal]] true)
  79   if offset then
  80     State.cursor1.pos = utf8.len(curr_line, 1, offset)
  81   end
  82   if offset == nil then
  83     -- search lines above cursor
  84     for i=State.cursor1.line-1,1,-1 do
  85       local curr_line = State.lines[i].data
  86       offset = rfind(curr_line, State.search_term, --[[from end]] nil, --[[literal]] true)
  87       if offset then
  88         State.cursor1 = {line=i, pos=utf8.len(curr_line, 1, offset)}
  89         break
  90       end
  91     end
  92   end
  93   if offset == nil then
  94     -- wrap around
  95     for i=#State.lines,State.cursor1.line+1,-1 do
  96       local curr_line = State.lines[i].data
  97       offset = rfind(curr_line, State.search_term, --[[from end]] nil, --[[literal]] true)
  98       if offset then
  99         State.cursor1 = {line=i, pos=utf8.len(curr_line, 1, offset)}
 100         break
 101       end
 102     end
 103   end
 104   if offset == nil then
 105     -- search current line after cursor
 106     local curr_line = State.lines[State.cursor1.line].data
 107     offset = rfind(curr_line, State.search_term, --[[from end]] nil, --[[literal]] true)
 108     local pos = utf8.len(curr_line, 1, offset)
 109     if pos and pos > State.cursor1.pos then
 110       State.cursor1.pos = pos
 111     end
 112   end
 113   if offset == nil then
 114     State.cursor1.line = State.search_backup.cursor.line
 115     State.cursor1.pos = State.search_backup.cursor.pos
 116     State.screen_top1.line = State.search_backup.screen_top.line
 117     State.screen_top1.pos = State.search_backup.screen_top.pos
 118   end
 119   local screen_bottom1 = Text.screen_bottom1(State)
 120   if Text.lt1(State.cursor1, State.screen_top1) or Text.lt1(screen_bottom1, State.cursor1) then
 121     State.screen_top1.line = State.cursor1.line
 122     local pos = Text.pos_at_start_of_screen_line(State, State.cursor1)
 123     State.screen_top1.pos = pos
 124   end
 125 end
 126
 127 function find(s, pat, i, plain)
 128   if s == nil then return end
 129   return s:find(pat, i, plain)
 130 end
 131
 132 -- TODO: avoid the expensive reverse() operations
 133 -- Particularly if we only care about literal matches, we don't need all of string.find
 134 function rfind(s, pat, i, plain)
 135   if s == nil then return end
 136   if #pat == 0 then return #s end
 137   local rs = s:reverse()
 138   local rpat = pat:reverse()
 139   if i == nil then i = #s end
 140   local ri = #s - i + 1
 141   local rendpos = rs:find(rpat, ri, plain)
 142   if rendpos == nil then return nil end
 143   local endpos = #s - rendpos + 1
 144   assert (endpos >= #pat, ('rfind: endpos %d should be >= #pat %d at this point'):format(endpos, #pat))
 145   return endpos-#pat+1
 146 end
 147
 148 function test_rfind()
 149   check_eq(rfind('abc', ''), 3, 'empty pattern')
 150   check_eq(rfind('abc', 'c'), 3, 'final char')
 151   check_eq(rfind('acbc', 'c', 3), 2, 'previous char')
 152   check_nil(rfind('abc', 'd'), 'missing char')
 153   check_nil(rfind('abc', 'c', 2), 'no more char')
 154 end