code / tomo-btui

   1 # An example program to pick a line of input from stdin
   2 use ../btui.tm
   3 
   4 _HELP := "
   5     A simple picker program
   6 "
   7 
   8 struct Picker(
   9     options:[Text],
  10     prompt=">",
  11     query="",
  12     offset:Int=0,
  13     max_height:Int?=20,
  14 )
  15     func draw(self:Picker)
  16         live_options := self.live_options()
  17         if chosen := self.chosen()
  18             write("\r\033[33;1m$(self.prompt)\033[m \033[2m$(chosen.replace(self.query, "\033[0;1m$(self.query)\033[0;2m"))\033[m\033[K")
  19         else
  20             write("\r\033[33;1m$(self.prompt)\033[m \033[31m$(self.query)\033[m\033[K")
  21 
  22         size := get_size()
  23         height := (self.max_height or size.y) _min_ size.y
  24         shown_options := live_options.to(height-1)
  25         for opt in shown_options
  26             write("\r\n\033[K$opt")
  27         clear(Below)
  28         move_cursor(ScreenVec2(0, -shown_options.length), relative=yes)
  29         flush()
  30 
  31     func update(self:&Picker)
  32         key := get_key()
  33         when key
  34         is "Ctrl-c"
  35             write("\r")
  36             clear(Right)
  37             clear(Below)
  38             disable()
  39             exit(code=1)
  40         is "Enter"
  41             write("\r")
  42             clear(Right)
  43             clear(Below)
  44             disable()
  45             if chosen := self.chosen()
  46                 say(chosen)
  47                 exit(code=0)
  48             else
  49                 exit(code=1)
  50         is "Backspace"
  51             self.query = self.query.to(-2)
  52         is "Space"
  53             self.query ++= " "
  54         is "Up", "Shift-Tab"
  55             self.offset -= 1
  56         is "Down", "Tab"
  57             self.offset += 1
  58         else if key.length == 1
  59             self.query ++= key
  60 
  61     func live_options(self:Picker -> [Text])
  62         return [o for o in self.options if o.has(self.query)]
  63 
  64     func chosen(self:Picker -> Text?)
  65         live_options := self.live_options()
  66         if live_options.length > 0
  67             return live_options[(1 + self.offset) mod1 live_options.length]
  68         else
  69             return none
  70 
  71 func main(choices:Path=(/dev/stdin), prompt|p=">", query|q="", max_height|H:Int?=20)
  72     lines := choices.lines() or fail("No such file: $choices")
  73     lines = [line for line in lines if line.length > 0]
  74     picker := Picker(
  75         options=lines,
  76         prompt=prompt,
  77         query=query,
  78         max_height=max_height,
  79     )
  80     set_mode(Normal)
  81     hide_cursor()
  82     picker.draw()
  83     repeat
  84         picker.draw()
  85         picker.update()
  86     disable()