// ------------------------------------------------------------------------
//   Project atila
//   Active Thing (activething.com) git.activething.com/go
//
//   File name  value_packer.go
//   Created by DEV
//   Modified   06/02/2024
//
//   Copyright 2024 activething.com 
// ------------------------------------------------------------------------
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ------------------------------------------------------------------------

package pkjson

import (
	"apacks"
	"codecs/cjson"
	"crypts"
	"encoding/json"
	"errs"
	"reflect"
	"time"
)


type (


	JSONPacker struct {
		state 	*apacks.State
		dirty 	bool
	}


	JSONPackerFnc func (packer *JSONPacker)
)


func NewJSONPacker(options ...JSONPackerFnc) *JSONPacker {
	pk := &JSONPacker{
		state : apacks.NewState(),
	}
	for _,o := range options {
		o(pk)
	}
	return pk
}



func (p *JSONPacker) Pack (value any, flags apacks.Flags) {
	if p.state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(p.state.Error))
	}
	if p.dirty {
		panic(apacks.G.ErrInvalidState)
	}
	p.dirty = true
	p.PackAny(value,flags)
}


func (p *JSONPacker) Packet () []byte {
	return p.state.Bytes() }


func (p *JSONPacker) Error () error {
	return p.state.Error }


func (p *JSONPacker) Reset () {
	p.state.Reset()
	p.dirty = false
}

func (p *JSONPacker) Release () {
	p.dirty = false
	apacks.ReleaseState(p.state)
}



func (p *JSONPacker) PackAny (value any, flags apacks.Flags) {
	if p.state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(p.state.Error))
	}
	if value == nil {
		p.state.W(cjson.G.NullValue)
		return
	}

	switch v := value.(type) {
	case apacks.PackBuilder:
		p.state.SetError(v.BuildPack(p))

	case json.Marshaler:
		d,e := v.MarshalJSON()
		if e != nil {
			p.state.SetError(e)
		} else {
			p.state.W(d)
		}

	case bool   : packBool  (p.state,v,flags )

	case string : packString(p.state,v,flags )

	case int    : packInt(p.state,int64(v),flags)
	case int8   : packInt(p.state,int64(v),flags)
	case int16  : packInt(p.state,int64(v),flags)
	case int32  : packInt(p.state,int64(v),flags)
	case int64	: packInt(p.state,v,flags )

	case uint   : packUInt(p.state,uint64(v),flags)
	case uint8  : packUInt(p.state,uint64(v),flags)
	case uint16 : packUInt(p.state,uint64(v),flags)
	case uint32 : packUInt(p.state,uint64(v),flags)
	case uint64 : packUInt(p.state,v,flags )

	case float32: packFloatString(p.state,float64(v),flags,32)
	case float64: packFloatString(p.state,v,flags,64)

	case time.Time: packDate (p.state,v,flags)

	case reflect.Value: rTypePacker(v.Type())(p.state,v,flags)

	case []uint8  :
		if flags.Binary() {
			packBinary(p.state,v,flags)
			return
		}
		packListUInt[uint8 ](p.state,v,flags)
	case []uint   : packListUInt [uint  ] (p.state,v,flags)
	case []uint16 : packListUInt [uint16] (p.state,v,flags)
	case []uint32 : packListUInt [uint32] (p.state,v,flags)
	case []uint64 : packListUInt [uint64] (p.state,v,flags)
	case []int    : packListInt  [int  ]  (p.state,v,flags)
	case []int8   : packListInt  [int8 ]  (p.state,v,flags)
	case []int16  : packListInt  [int16]  (p.state,v,flags)
	case []int32  : packListInt  [int32]  (p.state,v,flags)
	case []int64  : packListInt  [int64]  (p.state,v,flags)
	case []float32: packListFloat[float32](p.state,v,flags,32)
	case []float64: packListFloat[float64](p.state,v,flags,64)

	case []bool   : packListBool  (p.state,v,flags)
	case []string : packListString(p.state,v,flags)
	case []time.Time: packListDate(p.state,v,flags)

	default:
		rv := reflect.ValueOf(value)
		rTypePacker(rv.Type())(p.state,rv,flags)
	}
}




func (p *JSONPacker) PackRaw    (value []byte, flags apacks.Flags) { packRaw(p.state,value,flags) }

func (p *JSONPacker) PackBinary (value []byte, flags apacks.Flags) { packBinary(p.state,value,flags) }
func (p *JSONPacker) PackString (value string, flags apacks.Flags) { packString (p.state,value,flags) }

func (p *JSONPacker) PackBool   (value bool, flags apacks.Flags) { packBool(p.state,value,flags) }

func (p *JSONPacker) PackInt8   (value int8 , flags apacks.Flags) { packInt(p.state,int64(value),flags) }
func (p *JSONPacker) PackInt16  (value int16, flags apacks.Flags) { packInt(p.state,int64(value),flags) }
func (p *JSONPacker) PackInt32  (value int32, flags apacks.Flags) { packInt(p.state,int64(value),flags) }
func (p *JSONPacker) PackInt64  (value int64, flags apacks.Flags) { packInt(p.state,value,flags)}

func (p *JSONPacker) PackUInt8  (value uint8 , flags apacks.Flags) { packUInt(p.state,uint64(value),flags) }
func (p *JSONPacker) PackUInt16 (value uint16, flags apacks.Flags) { packUInt(p.state,uint64(value),flags) }
func (p *JSONPacker) PackUInt32 (value uint32, flags apacks.Flags) { packUInt(p.state,uint64(value),flags) }
func (p *JSONPacker) PackUInt64 (value uint64, flags apacks.Flags) { packUInt(p.state, value,flags) }

func (p *JSONPacker) PackFloat32 (value float32, flags apacks.Flags) { packFloatString(p.state, float64(value), flags, 32) }
func (p *JSONPacker) PackFloat64 (value float64, flags apacks.Flags) { packFloatString(p.state, value, flags, 64) }

func (p *JSONPacker) PackDate (value time.Time, flags apacks.Flags) { packDate(p.state,value,flags) }


func (p *JSONPacker) PackList  (builder func(apacks.ListPackBuilder, apacks.Flags), flags apacks.Flags)   {
	p.packCompound('[',']',builder==nil,func(pk *JSONPacker, fl apacks.Flags){ builder(pk,fl) },flags)
}

func (p *JSONPacker) PackMap   (builder func(apacks.MapPackBuilder, apacks.Flags), flags apacks.Flags)    {
	p.packCompound('{','}',builder==nil,func(pk *JSONPacker, fl apacks.Flags){ builder(pk,fl) },flags)
}

func (p *JSONPacker) PackObject(builder func(apacks.ObjectPackBuilder, apacks.Flags), flags apacks.Flags) {
	p.packCompound('{','}',builder==nil,func(pk *JSONPacker, fl apacks.Flags){ builder(pk,fl) },flags)
}


func (p *JSONPacker) packCompound (opener, closer byte, isnil bool, buildFn func(*JSONPacker, apacks.Flags), flags apacks.Flags) {
	if p.state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(p.state.Error))
	}
	if isnil {
		p.state.W(cjson.G.NullValue)
		return
	}

	dn := false
	defer func(d *bool) {
		if !(*d) {
			p.state.SetError(errs.ToError(recover()))
		}
	}(&dn)

	p.state.Open(opener)
	buildFn(p,flags)
	if p.state.Error != nil {
		return
	}
	p.state.Close(closer)
	dn = true
}



func packRaw (state *apacks.State, value []byte, flags apacks.Flags) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}
	if value == nil {
		state.W(cjson.G.NullValue)
		return
	}
	if len(value) == 0 {
		state.Write2Byte('"','"')
		return
	}
	state.WOQ(flags.Quote(),'"',value)
}

func packString (state *apacks.State, value string , flags apacks.Flags) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}

	if len(value) == 0 {
		state.Write2Byte('"','"')
		return
	}

	if flags.Encrypted() {
		packEncrypted(state, []byte(value), flags|apacks.FlagBinary64)
		return
	}

	if flags.Binary() {
		packBinary(state,[]byte(value),flags)
		return
	}

	cjson.WriteString(state.ABuffer,value,flags.EscapeHTML())
}


func packEncrypted (state *apacks.State, value []byte, flags apacks.Flags) {
	r := state.Encrypter.Encrypt(value)
	if !r.Ok() {
		state.SetError(r.Fail())
		return
	}

	if !flags.Binary() {
		flags|= apacks.FlagBinary64
	}

	packBinary(state,value,flags)
}


func packBinary (state *apacks.State, value []byte , flags apacks.Flags) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}

	if flags.Bin64() {
		state.SetError(cjson.WriteBase64(state.ABuffer,value))
		return
	}
	if flags.Bin32() {
		state.SetError(cjson.WriteBase32(state.ABuffer,value))
		return
	}
	state.SetError(apacks.G.ErrUnsupportedType)
}


func packBool   (state *apacks.State, value bool   , flags apacks.Flags) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}
	cjson.WriteBool(state.ABuffer,value,flags.Quote())
}


func packInt 	(state *apacks.State, value int64  , flags apacks.Flags) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}
	cjson.WriteInt(state.ABuffer,value,flags.Quote())
}


func packUInt 	(state *apacks.State, value uint64 , flags apacks.Flags) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}
	cjson.WriteUint(state.ABuffer,value,flags.Quote())
}

func packFloat  (state *apacks.State, value float64, flags apacks.Flags) {
	packFloatString(state, value, flags, 64) }


func packFloatString (state *apacks.State, f float64, flags apacks.Flags, bits int) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}
	cjson.WriteFloat(state.ABuffer,f,bits,flags.Quote())
}


func packDate(state *apacks.State, value time.Time, flags apacks.Flags) {
	if state.Error != nil {
		panic(apacks.G.ErrInvalidState.WrapWithCause(state.Error))
	}
	cjson.WriteDate(state.ABuffer,value,flags.DateFormat(),true)
}






func packListString (state *apacks.State, list []string, flags apacks.Flags) {
	if !checkList(state,list == nil, len(list) ==0) {
		return
	}
	state.WriteByte('[')
	for i,v := range list {
		if i > 0 {
			state.WriteByte(',')
		}
		packString(state,v,flags)
		if state.Error != nil {
			return
		}
	}
	state.WriteByte(']')
}


func packListBool (state *apacks.State, list []bool, flags apacks.Flags) {
	if !checkList(state,list == nil, len(list) ==0) {
		return
	}
	state.WriteByte('[')
	for i,v := range list {
		if i > 0 {
			state.WriteByte(',')
		}
		packBool(state,v,flags)
		if state.Error != nil {
			return
		}
	}
	state.WriteByte(']')
}


func packListInt  [T int | int8 | int16 | int32 | int64](state *apacks.State, list []T, flags apacks.Flags) {
	if !checkList(state,list == nil, len(list) ==0) {
		return
	}
	state.WriteByte('[')
	for i,v := range list {
		if i > 0 {
			state.WriteByte(',')
		}
		packInt(state,int64(v),flags)
		if state.Error != nil {
			return
		}
	}
	state.WriteByte(']')
}


func packListUInt [T uint | uint8 | uint16 | uint32 | uint64](state *apacks.State, list []T, flags apacks.Flags) {
	if !checkList(state,list == nil, len(list) ==0) {
		return
	}
	state.WriteByte('[')
	for i,v := range list {
		if i > 0 {
			state.WriteByte(',')
		}
		packUInt(state,uint64(v),flags)
		if state.Error != nil {
			return
		}
	}
	state.WriteByte(']')
}


func packListFloat[T float32 | float64](state *apacks.State, list []T, flags apacks.Flags, bits int) {
	if !checkList(state,list == nil, len(list) ==0) {
		return
	}
	state.WriteByte('[')
	for i,v := range list {
		if i > 0 {
			state.WriteByte(',')
		}
		packFloatString(state,float64(v),flags,bits)
		if state.Error != nil {
			return
		}
	}
	state.WriteByte(']')
}

func packListDate (state *apacks.State, list []time.Time, flags apacks.Flags) {
	if !checkList(state,list == nil, len(list) ==0) {
		return
	}
	state.WriteByte('[')
	for i,v := range list {
		if i > 0 {
			state.WriteByte(',')
		}
		packDate(state,v,flags)
		if state.Error != nil {
			return
		}
	}
	state.WriteByte(']')
}


func checkList (state *apacks.State, isNull, isEmpty bool) bool {
	if isNull {
		state.Write2Byte('"','"')
		return false
	}
	if isEmpty {
		state.Write2Byte('[',']')
		return false
	}
	return true
}



func WithEncrypter(encrypter crypts.Encrypter) JSONPackerFnc {
	return func(p *JSONPacker) {
		if encrypter == nil {
			encrypter = crypts.EncrypterNop{}
		}
		p.state.Encrypter = encrypter
	}
}