module Ethon::Curls::Options

def self.option(ftype,name,type,num,opts=nil)
  case type
  when :enum
    if opts.is_a? Array then
      opts=Hash[opts.each_with_index.to_a]
    elsif not opts.is_a? Hash then
      raise TypeError, "Ethon::Curls::Options #{ftype} #{name} Expected opts to be an Array or a Hash."
    end
  when :bitmask
    if opts.is_a? Array then
      if opts.last.is_a? Hash then
        hopts=opts.pop
      else
        hopts={}
      end
      opts.each_with_index do |v,i|
          next if v.nil?
          if i==0 then
            hopts[v]=0
          else
            hopts[v]=1<<(i-1)
          end
      end
      opts=hopts
    elsif not opts.is_a? Hash then
      raise TypeError, "Ethon::Curls::Options #{ftype} #{name} Expected opts to be an Array or a Hash."
    end
    opts[:all]=-1 unless opts.include? :all
    opts.each do |k,v|
      if v.is_a? Array then
        opts[k]=v.map { |b| opts[b] }.inject :|
      end
    end
  when :buffer
    raise TypeError, "Ethon::Curls::Options #{ftype} #{name} Expected opts to be an Array or a Hash." unless opts.is_a? Integer
  else
    raise ArgumentError, "Ethon::Curls::Options #{ftype} #{name} Expected no opts." unless opts.nil?
  end
  opthash=const_get("#{ftype.to_s.upcase}_OPTIONS")
  opthash[name]={:type=>type, :opt=>OPTION_TYPE_BASE[OPTION_TYPE_MAP[type]]+num, :opts=>opts}
end

def self.option_alias(ftype,name,*aliases)
  opthash=const_get("#{ftype.to_s.upcase}_OPTIONS")
  aliases.each { |a| opthash[a]=opthash[name] }
end

def self.option_type(type)
  cname="#{type.to_s.upcase}_OPTIONS"
  c=const_set(cname,{})
  eval %Q<
    def #{type.to_s.downcase}_options(rt=nil)
      return #{cname}.map { |k,v| [k,v[:opt]] } if rt==:enum
      #{cname}
    end
  >
end

def set_option(option, value, handle, type = :easy)
  raise NameError, "Ethon::Curls::Options unknown type #{type}." unless respond_to?("#{type.to_s.downcase}_options")
  opthash=send("#{type.to_s.downcase}_options")
  raise Errors::InvalidOption.new(option) unless opthash.include?(option)
  case opthash[option][:type]
  when :none
    return if value.nil?
    value=1
    func=:long
  when :int
    return if value.nil?
    func=:long
    value=value.to_i
  when :bool
    return if value.nil?
    func=:long
    value=(value&&value!=0) ? 1 : 0
  when :time
    return if value.nil?
    func=:long
    value=value.to_i
  when :enum
    return if value.nil?
    func=:long
    value=opthash[option][:opts][value] if value.is_a? Symbol
    value=value.to_i
  when :bitmask
    return if value.nil?
    func=:long
    value=opthash[option][:opts][value] if value.is_a? Symbol
    value=value.inject(0) { |res,v| res|opthash[option][:opts][v] } if value.is_a? Array
    value=value.to_i
  when :string
    func=:string
    value=value.to_s unless value.nil?
  when :string_escape_null
    func=:string
    value=Util.escape_zero_byte(value) unless value.nil?
  when :ffipointer
    func=:ffipointer
    raise Errors::InvalidValue.new(option,value) unless value.nil? or value.is_a? FFI::Pointer
  when :curl_slist
    func=:ffipointer
    raise Errors::InvalidValue.new(option,value) unless value.nil? or value.is_a? FFI::Pointer
  when :buffer
    raise NotImplementedError, "Ethon::Curls::Options option #{option} buffer type not implemented."
  when :dontuse_object
    raise NotImplementedError, "Ethon::Curls::Options option #{option} type not implemented."
  when :cbdata
    raise NotImplementedError, "Ethon::Curls::Options option #{option} callback data type not implemented. Use Ruby closures."
  when :callback
    func=:callback
    raise Errors::InvalidValue.new(option,value) unless value.nil? or value.is_a? Proc
  when :debug_callback
    func=:debug_callback
    raise Errors::InvalidValue.new(option,value) unless value.nil? or value.is_a? Proc
  when :off_t
    return if value.nil?
    func=:off_t
    value=value.to_i
  end
  if func==:long or func==:off_t then
      bits=FFI.type_size(:long)*8 if func==:long
      bits=FFI.type_size(:int64)*8 if func==:off_t
      tv=((value<0) ? value.abs-1 : value)
      raise Errors::InvalidValue.new(option,value) unless tv<(1<<bits)
  end
  send("#{type}_setopt_#{func}", handle, opthash[option][:opt], value)
end