#!/usr/bin/ruby

# Silence Ctrl-C's
trap('INT'){ exit 1 }

if Signal.list.include? 'PIPE'
  trap('PIPE', 'EXIT')
end

require 'optparse'
require 'gist'

# For the holdings of options.
options = {}
filenames = []

OptionParser.new do |opts|
  executable_name = File.split($0)[1]
  opts.banner = <<-EOS
Gist (v#{Gist::VERSION}) lets you upload to https://gist.github.com/

The content to be uploaded can be passed as a list of files, if none are
specified STDIN will be read. The default filename for STDIN is "a.rb", and all
filenames can be overridden by repeating the "-f" flag. The most useful reason
to do this is to change the syntax highlighting.

All gists must to be associated with a GitHub account, so you will need to login with
`gist --login` to obtain an OAuth2 access token. This is stored and used by gist in the future.

Private gists do not have guessable URLs and can be created with "-p", you can
also set the description at the top of the gist by passing "-d".

If you would like to shorten the resulting gist URL, use the -s flag. This will
use GitHub's URL shortener, git.io. You can also use -R to get the link to the
raw gist.

To copy the resulting URL to your clipboard you can use the -c option, or to
just open it directly in your browser, use -o. Using the -e option will copy the
embeddable URL to the clipboard. You can add `alias gist='gist -c'` to your
shell's rc file to configure this behaviour by default.

Instead of creating a new gist, you can update an existing one by passing its ID
or URL with "-u". For this to work, you must be logged in, and have created the
original gist with the same GitHub account.

If you want to skip empty files, use the --skip-empty flag. If all files are
empty no gist will be created.

Usage: #{executable_name} [-o|-c|-e] [-p] [-s] [-R] [-d DESC] [-u URL]
                          [--skip-empty] [-P] [-f NAME|-t EXT]* FILE*
       #{executable_name} --login
       #{executable_name} [-l|-r]

  EOS

  opts.on("--login", "Authenticate gist on this computer.") do
    Gist.login!
    exit
  end

  opts.on("-f", "--filename [NAME.EXTENSION]", "Sets the filename and syntax type.") do |filename|
    filenames << filename
    options[:filename] = filename
  end

  opts.on("-t", "--type [EXTENSION]", "Sets the file extension and syntax type.") do |extension|
    filenames << "foo.#{extension}"
    options[:filename] = "foo.#{extension}"
  end

  opts.on("-p", "--private", "Makes your gist private.") do
    options[:private] = true
  end

  opts.on("--no-private") do
    options[:private] = false
  end

  opts.on("-d", "--description DESCRIPTION", "Adds a description to your gist.") do |description|
    options[:description] = description
  end

  opts.on("-s", "--shorten", "Shorten the gist URL using git.io.") do |shorten|
    options[:shorten] = shorten
  end

  opts.on("-u", "--update [ URL | ID ]", "Update an existing gist.") do |update|
    options[:update] = update
  end

  opts.on("-c", "--copy", "Copy the resulting URL to the clipboard") do
    options[:copy] = true
  end

  opts.on("-e", "--embed", "Copy the embed code for the gist to the clipboard") do
    options[:embed] = true
    options[:copy] = true
  end

  opts.on("-o", "--open", "Open the resulting URL in a browser") do
    options[:open] = true
  end

  opts.on("--no-open")

  opts.on("--skip-empty", "Skip gisting empty files") do
    options[:skip_empty] = true
  end

  opts.on("-P", "--paste", "Paste from the clipboard to gist") do
    options[:paste] = true
  end

  opts.on("-R", "--raw", "Display raw URL of the new gist") do
    options[:raw] = true
  end

  opts.on("-l", "--list [USER]", "List all gists for user") do |user|
    options[:list] = user
  end

  opts.on("-r", "--read ID [FILENAME]", "Read a gist and print out the contents") do |id|
    options[:read] = id
  end

  opts.on("--delete [ URL | ID ]", "Delete a gist") do |id|
    options[:delete] = id
  end

  opts.on_tail("-h","--help", "Show this message.") do
    puts opts
    exit
  end

  opts.on_tail("-v", "--version", "Print the version.") do
    puts "gist v#{Gist::VERSION}"
    exit
  end

end.parse!

begin
  if Gist.auth_token.nil?
    puts 'Please log in with `gist --login`. ' \
      '(GitHub now requires credentials to gist https://bit.ly/2GBBxKw)'
    exit(1)
  end

  options[:output] = if options[:embed] && options[:shorten]
                       raise Gist::Error, "--embed does not make sense with --shorten"
                     elsif options[:embed]
                       :javascript
                     elsif options[:shorten] and options[:raw]
                       :short_raw_url
                     elsif options[:shorten]
                       :short_url
                     elsif options[:raw]
                       :raw_url
                     else
                       :html_url
                     end

  options[:public] = Gist.should_be_public?(options)

  if options.key? :list
    if options[:list]
      Gist.list_all_gists(options[:list])
    else
      Gist.list_all_gists
    end
    exit
  end

  if options.key? :read
    file_name = ARGV.first
    Gist.read_gist(options[:read], file_name)
    exit
  end

  if options.key? :delete
    Gist.delete_gist(options[:delete])
    exit
  end

  if options[:paste]
    puts Gist.gist(Gist.paste, options)
  else
    to_read = ARGV.empty? ? ['-'] : ARGV
    files = {}
    to_read.zip(filenames).each do |(file, name)|
      files[name || file] =
        begin
          if file == '-'
            $stderr.puts "(type a gist. <ctrl-c> to cancel, <ctrl-d> when done)" if $stdin.tty?
            STDIN.read
          else
            File.read(File.expand_path(file))
          end
        rescue => e
          raise e.extend(Gist::Error)
        end
    end

    output = Gist.multi_gist(files, options)
    puts output if output
  end

rescue Gist::Error => e
  puts "Error: #{e.message}"
  exit 1
end