#!/usr/bin/env ruby
# -*- coding: utf-8 -*-

require 'optparse'
require 'fileutils'
require 'erb'
require 'yaml'
require 'pathname'

include FileUtils

def main()
    options = {
        "debug" => false,
        "username" => "",
        "email" => ""
    }
    option_parser = OptionParser.new do |opts|
        executable_name = File.basename($PROGRAM_NAME)
        opts.banner = "make jekyll blog which hosted in github
        Usage: #{executable_name} [options]    
        "
        opts.on("-d","--debug","debug") do 
            options["debug"] = true
        end
        opts.on("-u","--username name","your name in blog, like \"Larry Cai\"") do | name|
            options["username"] = name
        end
        opts.on("-e","--email email","email could be contacted in blog") do |name|
            options["email"] = name
        end
        opts.on("-g","--generate project","generate blog under project.github.com") do |name|
            unless name =~ /^[a-zA-Z0-9]+$/
                raise ArgumentError,"name should be [a-zA-Z0-9]"
            end
            options["command"] = "generate"
            options["account"] = name
        end 
        opts.on("-s","--show","show how to continue") do 
            options["command"] = "show"
        end          
    end

    option_parser.parse!

    puts options.inspect if options["debug"]
    
    case options["command"] 
    when "generate" then generate_project(options["account"],options["username"],options["email"],options["debug"])
    when "show" then showhelp() 
    else puts "--help for help"
    end    
end

def showhelp()
    puts "1. update your personal information in theme (TODO)"
    puts "2. create project in github.com and push this project"
    puts "3. follow http://pages.github.com/"    
end

def guess()
    username = "Larry Cai"
    email = "larry.caiyu@gmail.com"
    
    # scan ~/.gitconfig
    gitconfig = ".gitconfig"
    gconf = File.join(Dir.home, gitconfig)
    if File.exists?(gconf)
        puts "..scan `#{gconf}`"
        File.open(gconf).each do |record|
            name,value = record.split("=")
            name.gsub!(/\t*\s*/,'')
            # puts "[#{name}]" + ":" 
            case name
            when "name"  then username = value.gsub(/\t*\s*\n*/,'')
            when "email" then email = value.gsub(/ /,'')
            end
        end
    end
    # puts username + ":" + email
    return username,email
end
# http://stackoverflow.com/questions/5074327/most-appropriate-way-to-generate-directory-of-files-from-directory-of-template-f
def generate_project(account,username,email,debug)
    destination = account + ".github.com"
    #puts username, email
    gitusername,gitemail = guess() 
    username = gitusername if username.empty?
    email = gitemail if email.empty?
    source = File.dirname(__FILE__)+"/../templates"
    #puts "generate project \"#{destination}\" from source \"#{source}\""
    FileUtils.rmtree(destination)
    FileUtils.mkdir_p(destination)
    sourceroot=Pathname.new(source)
    sourcerealpath = sourceroot.cleanpath
    puts "generate project \"#{destination}\" from source \"#{sourcerealpath}\""     
    Dir.glob(File.join(source, '**/*')).each do |path|
      pathname = Pathname.new(path)
      relative = pathname.relative_path_from(sourceroot)
      #puts "parent:" , sourceroot
      #puts "relative:", relative
      if File.directory?(pathname) 
        destdir = File.join(destination, relative.dirname)
        #puts "create #{destdir} "
        FileUtils.mkdir_p(destdir) 
      else
          FileUtils.mkdir_p(File.join(destination, relative.dirname))
          if pathname.extname == '.erb'
            #puts pathname.basename.sub(/\.erb$/, '')
            #puts destination
            #puts relative.dirname
            #puts File.join(destination,relative.dirname,pathname.basename.sub(/\.erb$/, ''))
            target = File.join(destination,relative.dirname,pathname.basename.sub(/\.erb$/, ''))
            if debug == true
                print " ", pathname.cleanpath, " => ", target,"\n"
            end
            File.open(target, 'w') do |file|
              file.puts(ERB.new(File.read(path)).result(binding))
            end   
          else
            if debug == true
                print " ", pathname.cleanpath, " => ", File.join(destination, relative.dirname),"\n"
            end
            FileUtils.cp(pathname, File.join(destination, relative.dirname))
          end
      end
    end
      puts 
      puts "The blog is now yours"
      puts "=> name:" + username
      puts "=> email:" + email
      puts "=> github: http://github.com/" + account
      puts "please run `cd " + account + ".github.com/"  + " ; jekyll --server'"
      puts "Then and open browser to http://localhost:4000 see the magic"
end

main