Class: Charming::Markdown::Renderer

Inherits:
Object
  • Object
show all
Defined in:
lib/charming/presentation/markdown/renderer.rb

Overview

Renderer is the top-level Markdown-to-ANSI renderer. Parses the content with Kramdown, then walks the document’s block and inline trees to produce styled terminal output. Code blocks are highlighted via Rouge when ‘syntax_highlighting` is enabled.

Constant Summary collapse

DEFAULT_RULE_WIDTH =

Wrap width used by ‘render_rule` when no width is otherwise specified.

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Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(content:, width: nil, theme: UI::Theme.default, syntax_highlighting: true) ⇒ Renderer

content is the Markdown source string. width optionally wraps paragraphs to that many display columns. theme is the Charming theme used to style blocks/inlines. syntax_highlighting enables Rouge-backed code block highlighting (default true).



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# File 'lib/charming/presentation/markdown/renderer.rb', line 21

def initialize(content:, width: nil, theme: UI::Theme.default, syntax_highlighting: true)
  @content = content
  @width = width
  @theme = theme || UI::Theme.default
  @syntax_highlighting = syntax_highlighting
end

Instance Attribute Details

#content ⇒ Object (readonly)

The Markdown source, configured wrap width, theme, and syntax-highlighting flag.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 16

def content
  @content
end

#syntax_highlighting ⇒ Object (readonly)

The Markdown source, configured wrap width, theme, and syntax-highlighting flag.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 16

def syntax_highlighting
  @syntax_highlighting
end

#theme ⇒ Object (readonly)

The Markdown source, configured wrap width, theme, and syntax-highlighting flag.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 16

def theme
  @theme
end

#width ⇒ Object (readonly)

The Markdown source, configured wrap width, theme, and syntax-highlighting flag.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 16

def width
  @width
end

Instance Method Details

#render ⇒ Object

Parses the content and returns the fully-rendered Markdown as a single string.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 29

def render
  document = Kramdown::Document.new(content.to_s)
  render_blocks(document.root.children)
end

#render_blocks(elements, list_depth: 0, width: @width) ⇒ Object

Renders a list of Kramdown block elements into a string, joined by blank lines. list_depth is forwarded to the render context for list indentation. width defaults to the renderer’s configured width.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 37

def render_blocks(elements, list_depth: 0, width: @width)
  context = RenderContext.from(width: width, list_depth: list_depth)
  elements.filter_map do |element|
    rendered = block_renderer.render(element, context: context)
    rendered unless rendered.to_s.empty?
  end.join("\n\n")
end

#render_inlines(elements, width: @width) ⇒ Object

Renders a list of Kramdown inline elements into a single concatenated string. width defaults to the renderer’s configured width.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 47

def render_inlines(elements, width: @width)
  context = RenderContext.from(width: width)
  elements.map { |element| inline_renderer.render(element, context: context) }.join
end

#style_for(name, fallback:) ⇒ Object

Returns the theme’s style for name if the theme defines it, otherwise returns fallback. Lets views override markdown-specific theme tokens.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 62

def style_for(name, fallback:)
  return theme.public_send(name) if theme.respond_to?(name)

  fallback
end

#theme_style(name) ⇒ Object

Returns the theme’s style for name, building a one-token default theme when the active theme doesn’t define it. Used as a final fallback for markdown styling.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 70

def theme_style(name)
  return theme.public_send(name) if theme.respond_to?(name)

  UI::Theme::DEFAULT_TOKENS.fetch(name).then { |token| UI::Theme.new(name => token).public_send(name) }
end

#wrap(value, width:) ⇒ Object

Word-wraps value to width display columns (when width is given), preserving any ANSI styling on each line. Returns value unchanged when width is nil.



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# File 'lib/charming/presentation/markdown/renderer.rb', line 54

def wrap(value, width:)
  return value unless width

  value.to_s.lines(chomp: true).map { |line| wrap_line(line, width) }.join("\n")
end