class RubyXL::Workbook

def [](worksheet)
  return worksheets[worksheet]
end

def date_to_num(date)
  return nil if date.nil?
  if @date1904
    compare_date = DateTime.parse('December 31, 1903')
  else
    compare_date = DateTime.parse('December 31, 1899')
  end
  # add one day to compare date for erroneous 1900 leap year compatibility
  date.ajd + 1 - compare_date.ajd
end

def fill_shared_strings()
  if @shared_strings.nil?
    string_hash = {}
    string_index = 0
    @num_strings = 0
    #fill hash for shared strings
    @worksheets.each do |sheet|
      unless sheet.nil?
        sheet.sheet_data.each do |row|
          row.each do |cell|
            unless cell.nil? || cell.value.nil?
              #if string not already seen, add it to hash
              if cell.datatype == 's'
                if string_hash[cell.value.to_s].nil?
                  string_hash[string_index]=cell.value.to_s
                  string_hash[cell.value.to_s]=string_index
                  string_index += 1
                end
                @num_strings += 1
              end
            end
          end
        end
      end
    end
    if string_hash.empty?
      @shared_strings = nil
    else
      @shared_strings = string_hash
      @size = string_index
    end
  end
end

def fill_styles()
  @fonts = {
             '0' => {
                      :font => {
                                 :sz   => { :attributes => { :val => 10 } },
                                 :name => { :attributes => { :val => "Verdana" } }
                               },
                      :count=>1
                    },
             '1' => {
                      :font => {
                                 :sz   => { :attributes => { :val => 8 } },
                                 :name => { :attributes => { :val => "Verdana" } }
                               },
                      :count=>0
                    }
           }
  @fills = {
             '0' => {
                      :fill => {
                                 :patternFill => { :attributes => { :patternType => "none" } }
                               },
              :count=>1} ,
             '1' => {
                      :fill => {
                                 :patternFill => { :attributes => { :patternType => "gray125" } }
                               },
                      :count=>0
                    }
           }
  @borders = {
               '0' => {
                        :border => {
                                     :left => { },
                                     :right => { },
                                     :top => { },
                                     :bottom => { },
                                     :diagonal => { }
                                   },
                        :count => 1 #count = how many styles reference it
                      }
             }
  @cell_style_xfs = {
                    :attributes => {
                                     :count => 1
                                   },
                    :xf => {
                             :attributes => { :numFmtId => 0, :fontId => 0, :fillId => 0, :borderId => 0 }
                           }
                  }
  @cell_xfs = {
                    :attributes => {
                                     :count => 1
                                   },
                    :xf => {
                             :attributes => { :numFmtId => 0, :fontId => 0, :fillId => 0, :borderId => 0, :xfId => 0 }
                           }
                  }
  @cell_styles = {
                  :cellStyle => {
                                  :attributes => { :builtinId=>0, :name=>"Normal", :xfId=>0 }
                                },
                  :attributes => { :count => 1 }
                }
end

def get_fill_color(xf_attributes)
  if @fills[xf_attributes[:fillId]].nil? || @fills[xf_attributes[:fillId]][:fill].nil? || @fills[xf_attributes[:fillId]][:fill][:patternFill].nil? || @fills[xf_attributes[:fillId]][:fill][:patternFill][:fgColor].nil?
    'ffffff' #white
  else
    @fills[xf_attributes[:fillId]][:fill][:patternFill][:fgColor][:attributes][:rgb]
  end
end

def get_style(style_index)
  if !@cell_xfs[:xf].is_a?Array
    @cell_xfs[:xf] = [@cell_xfs[:xf]]
  end
  xf_obj = @cell_xfs[:xf]
  if xf_obj.is_a?Array
    xf_obj = xf_obj[Integer(style_index)]
  end
  xf_obj
end

def get_style_attributes(xf_obj)
  if xf_obj.is_a?Array
    xf = xf_obj[1]
  else
    xf = xf_obj[:attributes]
  end
end

def initialize(worksheets=[], filepath=nil, creator=nil, modifier=nil, created_at=nil,
               company='', application=APPLICATION,
               appversion=APPVERSION, date1904=0)
  if worksheets.nil? || worksheets.empty?
    @worksheets       = [Worksheet.new(self,SHEET_NAME)]
  else
    @worksheets       = worksheets
  end
  @filepath           = filepath
  @creator            = creator
  @modifier           = modifier
  @company            = company
  @application        = application
  @appversion         = appversion
  @num_fmts           = nil
  @fonts              = nil
  @fills              = nil
  @borders            = nil
  @cell_xfs           = nil
  @cell_style_xfs     = nil
  @cell_styles        = nil
  @shared_strings     = nil
  @calc_chain         = nil #unnecessary?
  @num_strings        = 0 #num strings total
  @size               = 0 #num strings in shared_strings array
  @date1904           = date1904 > 0
  @external_links     = nil
  @style_corrector    = nil
  @drawings           = nil
  @worksheet_rels     = nil
  @printer_settings   = nil
  @macros             = nil
  @colors             = nil
  @shared_strings_XML = nil
  @defined_names      = nil
  begin
    @created_at       = DateTime.parse(created_at).strftime('%Y-%m-%dT%TZ')
  rescue
    t = Time.now
    @created_at       = t.strftime('%Y-%m-%dT%TZ')
  end
  @modified_at        = @created_at
  fill_styles()
  fill_shared_strings()
end

def num_to_date(num)
  return nil if num.nil?
  if @date1904
    compare_date = DateTime.parse('December 31, 1903')
  else
    compare_date = DateTime.parse('December 31, 1899')
  end
  # subtract one day to compare date for erroneous 1900 leap year compatibility
  compare_date - 1 + num
end

def validate_before_write
  ## TODO CHECK IF STYLE IS OK if not raise
end

def write(filepath=@filepath)
  validate_before_write
  if !(filepath =~ /(.+)\.xls(x|m)/)
    raise "Only xlsx and xlsm files are supported. Unsupported type for file: #{filepath}"
  end
  dirpath = ''
  extension = 'xls'
  if(filepath =~ /((.|\s)*)\.xls(x|m)$/)
    dirpath = $1.to_s()
    extension += $3.to_s
  end
  filename = ''
  if(filepath =~ /\/((.|\s)*)\/((.|\s)*)\.xls(x|m)$/)
    filename = $3.to_s()
  end
  #creates zip file, writes each type of file to zip folder
  #zips package and renames it to xlsx.
  zippath = File.join(dirpath, filename + '.zip')
  File.unlink(zippath) if File.exists?(zippath)
  FileUtils.mkdir_p(File.join(dirpath,zippath))
  Zip::ZipFile.open(zippath, Zip::ZipFile::CREATE) do |zipfile|
    writer = Writer::ContentTypesWriter.new(dirpath,self)
    zipfile.get_output_stream('[Content_Types].xml') {|f| f.puts(writer.write())}
    writer = Writer::RootRelsWriter.new(dirpath,self)
    zipfile.get_output_stream(File.join('_rels','.rels')) {|f| f.puts(writer.write())}
    writer = Writer::AppWriter.new(dirpath,self)
    zipfile.get_output_stream(File.join('docProps','app.xml')) {|f| f.puts(writer.write())}
    writer = Writer::CoreWriter.new(dirpath,self)
    zipfile.get_output_stream(File.join('docProps','core.xml')) {|f| f.puts(writer.write())}
    writer = Writer::ThemeWriter.new(dirpath,self)
    zipfile.get_output_stream(File.join('xl','theme','theme1.xml')) {|f| f.puts(writer.write())}
    writer = Writer::WorkbookRelsWriter.new(dirpath,self)
    zipfile.get_output_stream(File.join('xl','_rels','workbook.xml.rels')) {|f| f.puts(writer.write())}
    writer = Writer::WorkbookWriter.new(dirpath,self)
    zipfile.get_output_stream(File.join('xl','workbook.xml')) {|f| f.puts(writer.write())}
    writer = Writer::StylesWriter.new(dirpath,self)
    zipfile.get_output_stream(File.join('xl','styles.xml')) {|f| f.puts(writer.write())}
    unless @shared_strings.nil?
      writer = Writer::SharedStringsWriter.new(dirpath,self)
      zipfile.get_output_stream(File.join('xl','sharedStrings.xml')) {|f| f.puts(writer.write())}
    end
    #preserves external links (exactly, no modification allowed)
    unless @external_links.nil?
      #-1 because of rels
      1.upto(@external_links.size-1) do |i|
        zipfile.get_output_stream(
          File.join('xl','externalLinks',"externalLink#{i}.xml")) {|f|
            f.puts(@external_links[i])
          }
      end
      @external_links['rels'].each_index do |i|
        unless @external_links['rels'][i].nil?
          zipfile.get_output_stream(
            File.join('xl','externalLinks','_rels',"externalLink#{i}.xml.rels")) {|f|
              f.puts(@external_links['rels'][i])
            }
        end
      end
    end
    #preserves drawings (exactly, no modification allowed)
    unless @drawings.nil?
      1.upto(@drawings.size) do |i|
        zipfile.get_output_stream(
        File.join('xl','drawings',"vmlDrawing#{i}.vml")) {|f|
          f.puts(@drawings[i])
        }
      end
    end
    unless @printer_settings.nil?
      1.upto(@printer_settings.size) do |i|
        zipfile.get_output_stream(
        File.join('xl','printerSettings',"printerSettings#{i}.bin")) {|f|
          f.puts(@printer_settings[i])
        }
      end
    end
    unless @worksheet_rels.nil?
      1.upto(@worksheet_rels.size) do |i|
        zipfile.get_output_stream(
        File.join('xl','worksheets','_rels',"sheet#{i}.xml.rels")) {|f|
          f.puts(@worksheet_rels[i])
        }
      end
    end
    unless @macros.nil?
      zipfile.get_output_stream(File.join('xl','vbaProject.bin')) {|f| f.puts(@macros)}
    end
    @worksheets.each_with_index do |sheet,i|
      writer = Writer::WorksheetWriter.new(dirpath,self,i)
      zipfile.get_output_stream(File.join('xl','worksheets',"sheet#{i+1}.xml")) {|f| f.puts(writer.write())}
    end
  end
  FileUtils.cp(zippath,File.join(dirpath,filename+".#{extension}"))
  FileUtils.cp(File.join(dirpath,filename+".#{extension}"),filepath)
  if File.exist?(filepath)
    FileUtils.rm_rf(dirpath)
  end
  return filepath
end