#!/usr/bin/env ruby
#
# Find text directions using Google directions.  You can put a home
# address in ~/.directions.  The first non-empty line will be used.  #
# comment out the rest of the line.
#
# We need two address -- FROM and DEST.  These are determined this way.
#
#  FROM address:
#   - Use the one in ~/.directions if we don't use the -o option
#   - If -o is used or none is found in ~/.directions use the first
#     command line argument
#   - If there is no such argument prompt the user
#
#  DEST address:
#   - Use the second command line argument
#   - If there is no such argument, prompt the user
#

require 'open-uri'
require 'cgi'

class Directions

  BASE_URL = 'http://jeffpalm.com/directions'

  def main(argv)

    # Arguments
    @verbose = false
    override = false
    args = []
    argv.each do |arg|
      if arg.match /^-+v/
        @verbose = true
      elsif arg.match /^-+o/
        override = true 
      elsif arg.match /^-+h/
        print_help
        return
      else
        args << arg
      end
    end
        
    # Check whether we've specified a home address in ~/.directions
    home_address = find_home_address
    note 'Home address: ' + home_address.to_s

    from = nil
    dest = nil    
    if !override && args.length < 2
      note 'Using home address'
      from = home_address
    else
      note 'Overriding home address'
    end

    if !from
      from = args.empty? ? prompt("From:") : args.shift
    end
    dest = args.empty? ? prompt("To:") : args.shift
    
    url  = BASE_URL + '/request.php'
    url += '?from=' + CGI.escape(from)
    url += '&dest=' + CGI.escape(dest)
    note url

    open(url).read
    spinner 'Loading',5

    url  = BASE_URL + '/get.php'
    output_results open(url).read
    
  end
  
  private

  def print_help
    def e(s)
      STDERR.puts s
    end
    e 'Usage: ' + File.basename($0) + ' [options] origin? destination?'
    e 'where options include:'
    e ' -o   Over ride and don\'t use address in ~/.directions'
    e ' -h   Print this message'
    e ' -v   Be loud'
    e 'You can put a home address in ~/.directions.  If this address'
    e 'exists it will used as the origin address.  You can over ride'
    e 'using this address with the -o option.  If no home address'
    e 'is exists in ~/.directions and none is given as an argument'
    e 'we prompt for it.  If no destination address is given on the'
    e 'command line, we prompt for it.'
    
  end

  def output_results(c)
    puts
    puts
    lines = c.split /\n/
    if lines.length < 3
      lines.each do |line|
        puts line
      end
      return
    end
    distance = lines.shift.strip
    duration = lines.shift.strip
    puts 'Distance: ' + distance
    puts 'Duration: ' + duration
    puts
    format = "%-10s %-10s %s\n"
    printf format, 'Distance', 'Duration', 'Directions'
    lines.each do |line|
      if line.match /^\d/
        dist,dur,desc = line.split /\t/
        printf format,dist,dur,desc
      else
        puts ' --- ' + line + ' ---'
      end
    end
  end

  def spinner(title,dur)
    arr = ['|', '/', '-', '\\']
    sleep_time = 0.1
    print title + ' ' + arr[0]
    i = 0
    0.upto(dur/sleep_time) do
      print "\b" + arr[i]
      STDOUT.flush
      sleep sleep_time
      i = (i+1) % arr.length
    end
  end
  
  def prompt(msg)
    addr = nil
    while !addr
      print msg + ' '
      addr = STDIN.readline
      addr.strip!
    end
    return addr
  end

  def note(s)
    STDERR.puts s if @verbose
  end
  
  def find_home_address
    f = File.join ENV['HOME'],'.directions'
    return nil if !File.exist? f
    IO.foreach f do |line|
      line = line.gsub /\#.*/,''
      line.strip!
      return line if line != ''
    end
    return nil
  end
  
end

Directions.new.main ARGV