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+App.width(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   if Text.lt1(State.cursor1, State.screen_top1) or Text.lt1(State.screen_bottom1, State.cursor1) then
  66     State.screen_top1.line = State.cursor1.line
  67     local pos = Text.pos_at_start_of_screen_line(State, State.cursor1)
  68     State.screen_top1.pos = pos
  69   end
  70 end
  71
  72 function Text.search_previous(State)
  73   -- search current line before cursor
  74   local curr_pos = State.cursor1.pos
  75   local curr_line = State.lines[State.cursor1.line].data
  76   local curr_offset = Text.offset(curr_line, curr_pos)
  77   local offset = rfind(curr_line, State.search_term, curr_offset-1, --[[literal]] true)
  78   if offset then
  79     State.cursor1.pos = utf8.len(curr_line, 1, offset)
  80   end
  81   if offset == nil then
  82     -- search lines above cursor
  83     for i=State.cursor1.line-1,1,-1 do
  84       local curr_line = State.lines[i].data
  85       offset = rfind(curr_line, State.search_term, --[[from end]] nil, --[[literal]] true)
  86       if offset then
  87         State.cursor1 = {line=i, pos=utf8.len(curr_line, 1, offset)}
  88         break
  89       end
  90     end
  91   end
  92   if offset == nil then
  93     -- wrap around
  94     for i=#State.lines,State.cursor1.line+1,-1 do
  95       local curr_line = State.lines[i].data
  96       offset = rfind(curr_line, State.search_term, --[[from end]] nil, --[[literal]] true)
  97       if offset then
  98         State.cursor1 = {line=i, pos=utf8.len(curr_line, 1, offset)}
  99         break
 100       end
 101     end
 102   end
 103   if offset == nil then
 104     -- search current line after cursor
 105     local curr_line = State.lines[State.cursor1.line].data
 106     offset = rfind(curr_line, State.search_term, --[[from end]] nil, --[[literal]] true)
 107     local pos = utf8.len(curr_line, 1, offset)
 108     if pos and pos > State.cursor1.pos then
 109       State.cursor1.pos = pos
 110     end
 111   end
 112   if offset == nil then
 113     State.cursor1.line = State.search_backup.cursor.line
 114     State.cursor1.pos = State.search_backup.cursor.pos
 115     State.screen_top1.line = State.search_backup.screen_top.line
 116     State.screen_top1.pos = State.search_backup.screen_top.pos
 117   end
 118   if Text.lt1(State.cursor1, State.screen_top1) or Text.lt1(State.screen_bottom1, State.cursor1) then
 119     State.screen_top1.line = State.cursor1.line
 120     local pos = Text.pos_at_start_of_screen_line(State, State.cursor1)
 121     State.screen_top1.pos = pos
 122   end
 123 end
 124
 125 function find(s, pat, i, plain)
 126   if s == nil then return end
 127   return s:find(pat, i, plain)
 128 end
 129
 130 -- TODO: avoid the expensive reverse() operations
 131 -- Particularly if we only care about literal matches, we don't need all of string.find
 132 function rfind(s, pat, i, plain)
 133   if s == nil then return end
 134   if #pat == 0 then return #s end
 135   local rs = s:reverse()
 136   local rpat = pat:reverse()
 137   if i == nil then i = #s end
 138   local ri = #s - i + 1
 139   local rendpos = rs:find(rpat, ri, plain)
 140   if rendpos == nil then return nil end
 141   local endpos = #s - rendpos + 1
 142   assert (endpos >= #pat, ('rfind: endpos %d should be >= #pat %d at this point'):format(endpos, #pat))
 143   return endpos-#pat+1
 144 end
 145
 146 function test_rfind()
 147   check_eq(rfind('abc', ''), 3, 'empty pattern')
 148   check_eq(rfind('abc', 'c'), 3, 'final char')
 149   check_eq(rfind('acbc', 'c', 3), 2, 'previous char')
 150   check_nil(rfind('abc', 'd'), 'missing char')
 151   check_nil(rfind('abc', 'c', 2), 'no more char')
 152 end