Implemented decent version of the CLI

Makefile

@@ -1,5 +1,5 @@
 build: $(wildcard src/**/*.cr) $(wildcard lexers/*xml) $(wildcard styles/*xml) shard.yml
-	shards build -Dstrict_multi_assign -Dno_number_autocast
+	shards build -Dstrict_multi_assign -Dno_number_autocast -d --error-trace
 release: $(wildcard src/**/*.cr) $(wildcard lexers/*xml) $(wildcard styles/*xml) shard.yml
 	shards build --release
 static: $(wildcard src/**/*.cr) $(wildcard lexers/*xml) $(wildcard styles/*xml) shard.yml

src/lexer.cr

@@ -5,6 +5,22 @@ module Tartrazine
     bake_folder "../lexers", __DIR__
   end
 
+  # Get the lexer object for a language name
+  # FIXME: support aliases, paths, mimetypes, etc
+  def self.lexer(name : String) : Lexer
+    Lexer.from_xml(LexerFiles.get("/#{name}.xml").gets_to_end)
+  end
+
+  # Return a list of all lexers
+  # FIXME: support aliases
+  def self.lexers : Array(String)
+    lexers = Set(String).new
+    LexerFiles.files.each do |file|
+      lexers << file.path.split("/").last.split(".").first
+    end
+    lexers.to_a.sort!
+  end
+
   # This implements a lexer for Pygments RegexLexers as expressed
   # in Chroma's XML serialization.
   #
@@ -173,8 +189,4 @@ module Tartrazine
 
   # A token, the output of the tokenizer
   alias Token = NamedTuple(type: String, value: String)
-
-  def self.lexer(name : String) : Lexer
-    Lexer.from_xml(LexerFiles.get("/#{name}.xml").gets_to_end)
-  end
 end

src/main.cr

@@ -1,35 +1,92 @@
+require "docopt"
 require "./**"
 
 HELP = <<-HELP
 tartrazine: a syntax highlighting tool
 
 Usage:
-
-  tartrazine FILE -f html [-t theme][--standalone][--line-numbers]
-                          [-l lexer] [-o output][--css]
+  tartrazine (-h, --help)
+  tartrazine FILE -f html [-t theme][--standalone][--line-numbers][-l lexer] [-o output]
+  tartrazine -f html -t theme --css
   tartrazine FILE -f terminal [-t theme][-l lexer][-o output]
   tartrazine FILE -f json [-o output]
   tartrazine --list-themes
   tartrazine --list-lexers
+  tartrazine --list-formatters
+  tartrazine --version
 
+Options:
   -f <formatter>      Format to use (html, terminal, json)
--t <theme>          Theme to use (see --list-themes)
--l <lexer>          Lexer (language) to use (see --list-lexers)
--o <output>         Output file (default: stdout)
---standalone        Generate a standalone HTML file
---css               Generate a CSS file for the theme
+  -t <theme>          Theme to use, see --list-themes [default: default-dark]
+  -l <lexer>          Lexer (language) to use, see --list-lexers [default: plaintext]
+  -o <output>         Output file. Default is stdout.
+  --standalone        Generate a standalone HTML file, which includes
+                      all style information. If not given, it will generate just
+                      a HTML fragment ready to include in your own page.
+  --css               Generate a CSS file for the theme called <theme>.css
   --line-numbers      Include line numbers in the output
+  -h, --help          Show this screen
+  -v, --version       Show version number
 HELP
 
-lexer = Tartrazine.lexer("crystal")
-theme = Tartrazine.theme(ARGV[1])
-# formatter = Tartrazine::Json.new
+options = Docopt.docopt(HELP, ARGV)
+
+# Handle version manually
+if options["--version"]
+  puts "tartrazine #{Tartrazine::VERSION}"
+  exit 0
+end
+
+if options["--list-themes"]
+  puts Tartrazine.themes.join("\n")
+  exit 0
+end
+
+if options["--list-lexers"]
+  puts Tartrazine.lexers.join("\n")
+  exit 0
+end
+
+if options["--list-formatters"]
+  puts "html\njson\nterminal"
+  exit 0
+end
+
+if options["-f"]
+  formatter = options["-f"].as(String)
+  case formatter
+  when "html"
     formatter = Tartrazine::Html.new
-formatter.standalone = true
-formatter.class_prefix = "hl-"
-formatter.line_number_id_prefix = "ln-"
-formatter.line_numbers = true
-formatter.highlight_lines = [3..7, 20..30]
-formatter.linkable_line_numbers = false
-formatter.wrap_long_lines = false
-puts formatter.format(File.read(ARGV[0]), lexer, theme)
+    formatter.standalone = options["--standalone"] != nil
+    formatter.line_numbers = options["--line-numbers"] != nil
+  when "terminal"
+    formatter = Tartrazine::Ansi.new
+  when "json"
+    formatter = Tartrazine::Json.new
+  else
+    puts "Invalid formatter: #{formatter}"
+    exit 1
+  end
+
+  theme = Tartrazine.theme(options["-t"].as(String))
+
+  if formatter.is_a?(Tartrazine::Html) && options["--css"]
+    File.open("#{options["-t"].as(String)}.css", "w") do |outf|
+      outf.puts formatter.get_style_defs(theme)
+    end
+    exit 0
+  end
+
+  lexer = Tartrazine.lexer(options["-l"].as(String))
+
+  input = File.open(options["FILE"].as(String)).gets_to_end
+  output = formatter.format(input, lexer, theme)
+
+  if options["-o"].nil?
+    puts output
+  else
+    File.open(options["-o"].as(String), "w") do |outf|
+      outf.puts output
+    end
+  end
+end

src/styles.cr

@@ -10,6 +10,11 @@ require "xml"
 module Tartrazine
   alias Color = Sixteen::Color
 
+  class ThemeFiles
+    extend BakedFileSystem
+    bake_folder "../styles", __DIR__
+  end
+
   def self.theme(name : String) : Theme
     begin
       return Theme.from_base16(name)
@@ -23,9 +28,16 @@ module Tartrazine
     end
   end
 
-  class ThemeFiles
-    extend BakedFileSystem
-    bake_folder "../styles", __DIR__
+  # Return a list of all themes
+  def self.themes
+    themes = Set(String).new
+    ThemeFiles.files.each do |file|
+      themes << file.path.split("/").last.split(".").first
+    end
+    Sixteen::DataFiles.files.each do |file|
+      themes << file.path.split("/").last.split(".").first
+    end
+    themes.to_a.sort!
   end
 
   class Style