Initial working version.

2026-09-29 19:10:32 +05:30
parent 4bd3cd23e6
commit 5cd2b38c9c
4 changed files with 1207 additions and 0 deletions
@@ -0,0 +1,320 @@
+package jaeson
+
+import (
+	"strconv"
+	"gitea.cozeon.cloud/anand.ekka-ext/parser"
+	"github.com/antlr/antlr4/runtime/Go/antlr"
+)
+
+type stackElem struct {
+	jsObj    *JSONObject
+	jsArr    *JSONArray
+	hasJsObj bool
+	hasJsArr bool
+}
+
+func (v *stackElem) Init() {
+	v.hasJsObj = false
+	v.hasJsArr = false
+}
+
+func (v *stackElem) GetJsObj() *JSONObject {
+	return v.jsObj
+}
+func (v *stackElem) GetJsArr() *JSONArray {
+	return v.jsArr
+}
+
+func (v *stackElem) GetHasJsObj() bool {
+	return v.hasJsObj
+}
+func (v *stackElem) GetHasJsArr() bool {
+	return v.hasJsArr
+}
+
+func (v *stackElem) PutJSONObject(jsnObj *JSONObject) {
+	v.hasJsObj = true
+	v.hasJsArr = false
+	v.jsObj = jsnObj
+}
+
+func (v *stackElem) PutJSONArray(jsnArr *JSONArray) {
+	v.hasJsObj = false
+	v.hasJsArr = true
+	v.jsArr = jsnArr
+}
+
+type jsonListener struct {
+	*parser.BaseJSONListener
+
+	topJsObj *JSONObject
+
+	currJsObj *JSONObject
+	currJsArr *JSONArray
+	currKey   string
+
+	childJsObj *JSONObject
+	childJsArr *JSONArray
+
+	foundKeyOfPair bool
+	jsonStartFound bool
+	topObjCreated  bool
+	arrStart       bool
+
+	parentObjStack []*stackElem
+
+	stckElemPointer int
+
+	topJsArr      *JSONArray
+	topArrCreated bool
+}
+
+func (s *jsonListener) GetLastElem() *stackElem {
+	return s.parentObjStack[s.stckElemPointer-1]
+}
+
+func (s *jsonListener) DeleteLastElem() {
+	s.parentObjStack[s.stckElemPointer-1] = nil
+	s.stckElemPointer -= 1
+}
+
+func (s *jsonListener) AddJSONObjToStack(jsObj *JSONObject) {
+	tmpStckElem := new(stackElem)
+	tmpStckElem.Init()
+	s.stckElemPointer += 1
+
+	if s.stckElemPointer > len(s.parentObjStack) {
+		s.parentObjStack = append(s.parentObjStack, tmpStckElem)
+	} else {
+		s.parentObjStack[s.stckElemPointer-1] = tmpStckElem
+	}
+
+	tmpStckElem.PutJSONObject(jsObj)
+}
+
+func (s *jsonListener) AddJSONArrToStack(jsArr *JSONArray) {
+	tmpStckElem := new(stackElem)
+	tmpStckElem.Init()
+	s.stckElemPointer += 1
+
+	if s.stckElemPointer > len(s.parentObjStack) {
+		s.parentObjStack = append(s.parentObjStack, tmpStckElem)
+	} else {
+		s.parentObjStack[s.stckElemPointer-1] = tmpStckElem
+	}
+
+	tmpStckElem.PutJSONArray(jsArr)
+}
+
+//--------------- Json Enter-Exit ---------------//
+func (s *jsonListener) EnterJson(ctx *parser.JsonContext) {
+	s.jsonStartFound = true
+	s.topObjCreated = false
+	s.stckElemPointer = 0
+}
+
+func (s *jsonListener) ExitJson(ctx *parser.JsonContext) {
+	// nothing needs to be implemented
+}
+
+//--------------- Obj Enter-Exit ---------------//
+func (s *jsonListener) EnterObj(ctx *parser.ObjContext) {
+
+	if !s.topObjCreated && !s.topArrCreated {
+		s.topJsObj = new(JSONObject)
+		s.topJsObj.Init()
+		s.currJsObj = s.topJsObj
+		s.foundKeyOfPair = false
+
+		s.topObjCreated = true
+		s.arrStart = false
+
+		//initialize stack
+		s.parentObjStack = make([]*stackElem, 0)
+
+		//Add topJsObj to stack
+		s.AddJSONObjToStack(s.topJsObj)
+
+	} else {
+
+		s.childJsObj = new(JSONObject)
+		s.childJsObj.Init()
+
+		if s.arrStart {
+			s.currJsArr.PutJSONObject(s.childJsObj)
+			s.AddJSONArrToStack(s.currJsArr)
+			s.currJsObj = s.childJsObj
+			s.arrStart = false
+
+		} else {
+			s.currJsObj.PutJSONObject(s.currKey, s.childJsObj)
+
+			// might need stack up or append curr object in a LIFO stack,
+			//	before takig on the new child object
+			s.AddJSONObjToStack(s.currJsObj)
+
+			s.currJsObj = s.childJsObj
+		}
+	}
+}
+
+func (s *jsonListener) ExitObj(ctx *parser.ObjContext) {
+
+	tmpPrevStckElem := s.GetLastElem()
+
+	if tmpPrevStckElem != nil {
+		if tmpPrevStckElem.GetHasJsObj() {
+			s.currJsObj = tmpPrevStckElem.GetJsObj()
+			s.arrStart = false
+
+		} else {
+			s.currJsArr = tmpPrevStckElem.GetJsArr()
+			s.arrStart = true
+		}
+		s.DeleteLastElem()
+
+	} //else {
+		// nothing needs to be implemented
+	//}
+
+}
+
+//--------------- Arr Enter-Exit ---------------//
+
+// EnterArr is called when production arr is entered.
+func (s *jsonListener) EnterArr(ctx *parser.ArrContext) {
+
+	if !s.topObjCreated && !s.topArrCreated {
+
+		s.topJsArr = new(JSONArray)
+		s.topJsArr.Init()
+		s.currJsArr = s.topJsArr
+
+		s.topArrCreated = true
+		s.arrStart = true
+
+		//initialize stack
+		s.parentObjStack = make([]*stackElem, 0)
+
+		//Add topJsArr to stack
+		s.AddJSONArrToStack(s.topJsArr)
+
+	} else {
+
+		if s.arrStart {
+
+			s.childJsArr = new(JSONArray)
+			s.childJsArr.Init()
+
+			//add currJsArr to stack
+			s.AddJSONArrToStack(s.currJsArr)
+			s.currJsArr.PutJSONArray(s.childJsArr)
+			s.currJsArr = s.childJsArr
+
+		} else {
+
+			s.currJsArr = new(JSONArray)
+			s.currJsArr.Init()
+			s.currJsObj.PutJSONArray(s.currKey, s.currJsArr)
+			s.AddJSONObjToStack(s.currJsObj)
+		}
+	}
+	s.arrStart = true
+}
+
+// ExitArr is called when production arr is exited.
+func (s *jsonListener) ExitArr(ctx *parser.ArrContext) {
+	s.arrStart = false
+
+	tmpPrevStckElem := s.GetLastElem()
+	if tmpPrevStckElem.GetHasJsObj() {
+		s.currJsObj = tmpPrevStckElem.GetJsObj()
+		s.arrStart = false
+
+	} else {
+		s.currJsArr = tmpPrevStckElem.GetJsArr()
+		s.arrStart = true
+	}
+	s.DeleteLastElem()
+}
+
+//--------------- Pair Enter-Exit ---------------//
+
+func (s *jsonListener) EnterPair(ctx *parser.PairContext) {
+	s.foundKeyOfPair = true
+	s.currKey = ctx.STRING().GetSymbol().GetText()
+	s.currKey = s.currKey[1 : len(s.currKey)-1]
+}
+
+func (s *jsonListener) ExitPair(ctx *parser.PairContext) {
+	s.foundKeyOfPair = false
+}
+
+//--------------- Value Enter-Exit ---------------//
+
+func (s *jsonListener) EnterValue(ctx *parser.ValueContext) {
+
+	if ctx.STRING() != nil {
+		val0 := ctx.STRING().GetSymbol().GetText()
+		val1 := val0[1 : len(val0)-1]
+
+		if s.arrStart {
+			s.currJsArr.PutString(val1)
+		} else {
+			s.currJsObj.PutString(s.currKey, val1)
+		}
+
+	}else if ctx.NUMBER() != nil {
+		val0 := ctx.NUMBER().GetSymbol().GetText()
+		vali, erri := strconv.ParseInt(val0, 10, 64)
+		if erri != nil {
+			valf, errf := strconv.ParseFloat(val0, 64)
+			if errf == nil {
+				s.currJsObj.PutFloat(s.currKey, valf)
+			} else {
+				// neither int nor float. then what is it ?
+			}
+		}else{
+			s.currJsObj.PutInt(s.currKey, int(vali))
+		}
+		
+		//s.currJsObj.PutInt(s.currKey, val1)
+
+	}else if ctx.Obj() != nil {
+		// nothing needs to be implemented
+
+	}else if ctx.BOOLEAN() != nil {
+
+		val0 := ctx.BOOLEAN().GetSymbol().GetText()
+		val1, _ := strconv.ParseBool(val0)
+		s.currJsObj.PutBool(s.currKey, val1)
+	}
+	s.foundKeyOfPair = false
+}
+
+func (s *jsonListener) ExitValue(ctx *parser.ValueContext) {
+	// nothing needs to be implemented
+}
+
+func UnmarshalJSON(jsonstr string) (*JSONObject, *JSONArray) {
+
+	is := antlr.NewInputStream(jsonstr)
+
+	// Create the Lexer
+	lexer := parser.NewJSONLexer(is)
+	stream := antlr.NewCommonTokenStream(lexer, antlr.TokenDefaultChannel)
+
+	// Create the Parser
+	p := parser.NewJSONParser(stream)
+
+	// Finally parse the expression
+	var jsonLstnr *jsonListener = new(jsonListener)
+	antlr.ParseTreeWalkerDefault.Walk(jsonLstnr, p.Json())
+
+	if jsonLstnr.topObjCreated {
+		return jsonLstnr.topJsObj, nil
+
+	} else {
+		return nil, jsonLstnr.topJsArr
+	}
+}