Class: Typr::Text

Inherits:
Stack show all
Defined in:
lib/text.rb

Overview

A vertically scrollable text viewer with word-wrapping, header bar, row selection via hint characters, and search.

Accepts String, IO, or StringIO input. Content is split into display rows by newlines and line width, then rendered as a sliding window.

Example

text = Typr::Text.new(
input: StringIO.new("Hello\nworld"),
header: "My Doc",
top: 2, left: 0.1, right: 0.9, bottom: -4,
border: :round,
colors: { header: [:yellow, :grey30] }
)
text.draw

Constant Summary

Constants included from Typr

COLORS, INPUT, KEY_DELETE, KEY_ENTER, KEY_ESCAPE, KEY_INSERT, KEY_PAGEDOWN, KEY_PAGEUP, KEY_RETURN, KEY_TAB, MIMETYPES, MODES, OUTPUT

Instance Attribute Summary collapse

Attributes inherited from Stack

#header, #hints, #hints_start, #keymap, #selected, #separator, #start

Attributes inherited from Space

#borders, #bottom, #colors, #interval, #left, #margin, #right, #top

Instance Method Summary collapse

Methods inherited from Stack

#cycle, #down, #draw_hints, #headspace, #height, #page, #page_down, #page_up, #pick, #reset, #send, #to_bottom, #to_top, #up

Methods inherited from Space

#border=, #draw_border, #height, #start, #stop, #width

Methods included from Typr

#background, clear, #color, #color_code, column, exit, #fade, #foreground, #get_background, #get_foreground, height, init, #mode, #mode_code, #move, #move_code, position, #prepare, #printables, read, #real_size, row, #show, size, width

Constructor Details

#initialize(args = {}) ⇒ Text

Creates a new Text widget.

text = Typr::Text.new(input: "hello", header: "Title")
text = Typr::Text.new(input: $stdin, tabspace: 4)


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# File 'lib/text.rb', line 130

def initialize args={}
  @tabspace = 2
  @data, @lines, @tail = "", [0], ""
  super args
  @colors = { header: :yellow }.merge( @colors || {} )
  @lastwidth = width
  self << @input
end

Instance Attribute Details

#tabspace ⇒ Object

Tabstop width in spaces. Default: 2.



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# File 'lib/text.rb', line 30

def tabspace
  @tabspace
end

Instance Method Details

#build(input = nil) ⇒ Object Also known as: <<

Rebuilds the internal line buffer from input. Splits text at newlines and word boundaries to fit the current width. Pass nil to re-parse from the existing buffer (triggered on resize).

text.build("one\ntwo three")  # => #<Typr::Text ...>
text << "appended line"       # alias for build


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# File 'lib/text.rb', line 39

def build input=nil
  ( @lines = [0]; input = "" ) if rebuild = !input
  return self if rebuild && input == ""
  input = StringIO.new( input.to_s.dup ) unless input.respond_to?(:read)
  @tail = ""
  until input.closed? or input.eof?
    capacity = width - @margin.size - @tail.length
    chunk = (capacity < 1) ? "x" : capacity
    line = @tail + input.read(chunk)
    if line.empty?
      break
    else
      wrap_idx = line.index("\n") || line.rindex(" ") || line.length
      wrap = [wrap_idx, line.length].min + 1
      @data += line[0...wrap]
      if wrap < line.length
        @tail = line[wrap..-1]
        @lines << @data.length
      else
        @tail = ""
      end
    end
    break if rebuild && line[-1] == "\n"
  end
  until @tail.empty?
    wrap_idx = @tail.index("\n") || @tail.rindex(" ") || @tail.length
    wrap = [wrap_idx, @tail.length].min + 1
    @data += @tail[0...wrap]
    if wrap < @tail.length
      @lines << @data.length
      @tail = @tail[wrap..-1]
    else
      @tail = ""
    end
  end
  @lines << @data.length unless @lines.last == @data.length
end

#draw ⇒ Object

Full draw cycle: rebuilds on resize, computes visible lines, and renders the viewport with borders and hints.

text.draw


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# File 'lib/text.rb', line 104

def draw
  (build; @lastwidth = width) if width != @lastwidth
  range = @lines[@start..@start+height]
  page = StringIO.new @data[range.first..range.last]
  @page=range[1..-1].map{|pos| page.read(pos-range.first-page.pos).rstrip}
  super
end

#positions(row) ⇒ Object

Returns word-boundary column offsets for a given page row. Used internally to place hint markers between words.

text.positions(2)  # => [0, 6, 10, ...]


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# File 'lib/text.rb', line 95

def positions row
  [0] + @page[row-1].chars.map.with_index{|c,i| i+1 if c == @separator}.compact
end

#print(row = nil) ⇒ Object

Renders a single display row. Pass an Integer for a content row or :header for the header bar.

text.print(:header)  # renders the header bar
text.print(3)        # renders row 3 of the current page


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# File 'lib/text.rb', line 84

def print row=nil
  header = ( row == :header )
  return super unless row and @lines[ row + 1 ] unless header
  show prepare( ( header ? @header : @page[ row-@start ] ), width )
end

#rows ⇒ Object

Total number of text lines in the buffer.

text.rows  # => 42


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# File 'lib/text.rb', line 116

def rows; @lines.count end

#search(query) ⇒ Object

Placeholder for text search. Currently unimplemented.

text.search("query")  # => nil


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# File 'lib/text.rb', line 122

def search query
end