package ipp

import (
	"encoding/binary"
	"fmt"
	"io"

	log "github.com/sirupsen/logrus"
)

// References
// https://tools.ietf.org/html/rfc8010
// https://tools.ietf.org/html/rfc8011

// Defined value tags
// from rfc8010
type tag uint8

const (
	// attribute group tags
	beginAttribute        tag = 0x00
	operationAttributes   tag = 0x01
	jobAttributes         tag = 0x02
	endOfAttributes       tag = 0x03
	printerAttributes     tag = 0x04
	unsupportedAttributes tag = 0x05
	// Out of band
	unsupportedValueTag tag = 0x10
	unknownValueTag     tag = 0x12
	noValueValueTag     tag = 0x13

	// Integer values
	integerValueTag tag = 0x21
	booleanValueTag tag = 0x22
	enumValueTag    tag = 0x23

	// octetString Tags
	octetStringValueTag      tag = 0x30
	dateTimeValueTag         tag = 0x31
	resolutionValueTag       tag = 0x32
	rangeOfIntegerValueTag   tag = 0x33
	begCollectionValueTag    tag = 0x34
	textWithLanguageValueTag tag = 0x35
	nameWithLanguageValueTag tag = 0x36
	endCollectionValueTag    tag = 0x37

	// Character string values
	textWithoutLanguagageValueTag tag = 0x41
	nameWithoutLanguagageValueTag tag = 0x42
	keyWordValueTag               tag = 0x44
	uriValueTag                   tag = 0x45
	uriSchemeValueTag             tag = 0x46
	charsetValueTag               tag = 0x47
	naturalLanguagageValueTag     tag = 0x48
	mimeMediaTypeValueTag         tag = 0x49
	memberAttrNameValueTag        tag = 0x4a
)

// Operation-id, defined in rfc8011
type operationId uint16

const (
	PrintJob             operationId = 0x0002
	PrintURI             operationId = 0x0003
	ValidateJob          operationId = 0x0004
	CreateJob            operationId = 0x0005
	SendDocument         operationId = 0x0006
	SendURI              operationId = 0x0007
	CancelJob            operationId = 0x0008
	GetJobAttributes     operationId = 0x0009
	GetJobs              operationId = 0x000a
	GetPrinterAttributes operationId = 0x000b
	HoldJob              operationId = 0x000c
	ReleaseJob           operationId = 0x000d
	RestartJob           operationId = 0x000e
	PausePrinter         operationId = 0x0010
	ResumePrinter        operationId = 0x0011
	PurgeJobs            operationId = 0x0012
)

type statusCode uint16

const (
	SuccessfulOk          statusCode = 0x0000
	ClientErrorBadRequest statusCode = 0x0400
)

type versionNumber uint16

func (v versionNumber) String() string {
	vn := uint16(v)
	return fmt.Sprintf("%x.%x", vn&0xff00>>8, vn&0x00ff)
}

type ippRequestHeader struct {
	versionNumber versionNumber
	operationId   operationId
	requestId     uint32
}

func (h *ippRequestHeader) marshal(byteStream io.Reader) {
	binary.Read(byteStream, binary.BigEndian, &h.versionNumber)
	binary.Read(byteStream, binary.BigEndian, &h.operationId)
	binary.Read(byteStream, binary.BigEndian, &h.requestId)
}

func (h ippRequestHeader) String() string {
	return fmt.Sprintf("Version number: %v Operation Id: %v Request Id: %v", h.versionNumber, h.operationId, h.requestId)
}

type Attribute interface {
	valueTag() tag
	unmarshal(io.Reader)
	marshal() []byte
	size() int
}

type Request struct {
	header              ippRequestHeader
	operationAttributes map[string]Attribute
	jobAttributes       map[string]Attribute
	printerAttributes   map[string]Attribute
}

func NewRequest() *Request {
	r := new(Request)
	r.operationAttributes = make(map[string]Attribute)
	r.jobAttributes = make(map[string]Attribute)
	r.printerAttributes = make(map[string]Attribute)

	return r
}

func (r Request) String() string {
	s := r.header.String() + "\n" + " OperationAttributes" + "\n"
	for _, a := range r.operationAttributes {
		s = s + fmt.Sprintf("  %v  (%v)\n", a, a.valueTag())
	}
	return s
}

// log.Info(r.Header)
// log.Info(r.ContentLength)

//body := make([]byte, r.ContentLength)
//body.Read(body)

func (r *Request) UnMarshal(body io.Reader) {
	r.header.marshal(body)
	log.Infof("Header %v", r.header)
	var tag tag
	err := binary.Read(body, binary.BigEndian, &tag)
	if err != nil {
		log.Error(err.Error())
	}
	log.Infof("got tag - %v", tag)

	if tag == operationAttributes {
	nextoperationattr:
		for tag != endOfAttributes {
			var lastKeyword *keyWord
			err = binary.Read(body, binary.BigEndian, &tag)
			if err != nil {
				log.Error(err.Error())
			}
			log.Infof("Value tag - %v", tag)
			switch tag {
			case endOfAttributes:
				err = binary.Read(body, binary.BigEndian, &tag)
				if err == io.EOF {
					// No more data
					return
				}
				if err != nil {
					log.Error(err.Error())
				}
				log.Infof("got tag - %v", tag)
				err = binary.Read(body, binary.BigEndian, &tag)
				if err != nil {
					log.Error(err.Error())
				}
				log.Infof("got tag - %v", tag)

				break nextoperationattr
			case charsetValueTag:
				c := NewCharSetValue("", "")
				c.unmarshal(body)
				r.operationAttributes[c.name] = c
				log.Infof("%v %v", c.name, c.value)
			case uriValueTag:
				u := newUriValue("", "")
				u.unmarshal(body)
				r.operationAttributes[u.name] = u
				log.Infof("%v %v", u.name, u.value)
			case naturalLanguagageValueTag:
				n := newNaturalLanguagage("", "")
				n.unmarshal(body)
				r.operationAttributes[n.name] = n
				log.Infof("%v %v", n.name, n.value)
			case keyWordValueTag:
				k := newKeyWord()
				k.unmarshal(body)
				r.operationAttributes[k.name] = k
				if k.name == "" {
					lastKeyword.addValue(k.values[0])
				} else {
					lastKeyword = k
				}
			default:
				log.Errorf("Unsupported tag %v", tag)

			}
		}
		log.Infof("Value tag %v", tag)
	} else {
		log.Error("unexpected tag")
		// TODO Return something sensible here

	}
}

func (r *Request) RequestId() uint32 {
	return r.header.requestId
}

func unmarshalSingleValue(byteStream io.Reader) (string, string) {
	var length uint16
	binary.Read(byteStream, binary.BigEndian, &length)
	//log.Infof("Length %v", length)
	attributeName := make([]byte, length)
	if length > 0 {
		binary.Read(byteStream, binary.BigEndian, attributeName)
		//log.Infof("Valuename %v", string(attributeName))
	}
	binary.Read(byteStream, binary.BigEndian, &length)
	//log.Infof("Length %v", length)
	attributeValue := make([]byte, length)
	binary.Read(byteStream, binary.BigEndian, attributeValue)
	//log.Infof("Value %v", string(attributeValue))
	return string(attributeName), string(attributeValue)
}

func marshalNameValue(name, value string, b []byte) {
	p := 0
	binary.BigEndian.PutUint16(b[p:p+2], uint16(len(name)))
	p += 2
	copy(b[p:], []byte(name))
	p += len(name)
	binary.BigEndian.PutUint16(b[p:p+2], uint16(len(value)))
	p += 2
	copy(b[p:], []byte(value))
}