1 files changed, 110 insertions, 0 deletions
diff --git a/internal/lexer/states.go b/internal/lexer/states.go
new file mode 100644
index 0000000..818ccf6
--- /dev/null
+++ b/internal/lexer/states.go
@@ -0,0 +1,110 @@
+package lexer
+
+func InitJson(l *Lexer) stateFunc {
+	ignoreWhiteSpace(l)
+	switch {
+	case l.Accept("{"):
+		l.Emit(LObjectStart)
+		return stateInObject
+	case l.Accept("["):
+		l.Emit(LArrayStart)
+	case l.Peek() == eof:
+		return nil
+	}
+	return l.Errorf("Unknown token: %s", string(l.Peek()))
+}
+
+func stateInObject(l *Lexer) stateFunc {
+	// we in object, so we expect field keys and values
+	ignoreWhiteSpace(l)
+	if l.Accept("}") {
+		l.Emit(LObjectEnd)
+		// If meet close object return to previous state (including initial)
+		return l.PopState()
+	}
+	ignoreWhiteSpace(l)
+	l.Accept(",")
+	ignoreWhiteSpace(l)
+	if !scanQuotedString(l, '"') {
+		return l.Errorf("Unknown token: %s", string(l.Peek()))
+	}
+	l.Emit(LObjectKey)
+	ignoreWhiteSpace(l)
+	if !l.Accept(":") {
+		return l.Errorf("Expected ':'")
+	}
+	ignoreWhiteSpace(l)
+	l.Emit(LObjectValue)
+	switch {
+	case scanQuotedString(l, '"'):
+		l.Emit(LString)
+		ignoreWhiteSpace(l)
+		l.Accept(",")
+		l.Ignore()
+		ignoreWhiteSpace(l)
+		return stateInObject
+	case scanNumber(l):
+		l.Emit(LNumber)
+		ignoreWhiteSpace(l)
+		l.Accept(",")
+		l.Ignore()
+		ignoreWhiteSpace(l)
+		return stateInObject
+	case l.AcceptAnyOf([]string{"true", "false"}, true):
+		l.Emit(LBoolean)
+		ignoreWhiteSpace(l)
+		l.Accept(",")
+		l.Ignore()
+		ignoreWhiteSpace(l)
+		return stateInObject
+	case l.AcceptString("null", true):
+		l.Emit(LNull)
+		ignoreWhiteSpace(l)
+		l.Accept(",")
+		l.Ignore()
+		ignoreWhiteSpace(l)
+		return stateInObject
+	case l.Accept("{"):
+		l.Emit(LObjectStart)
+		l.PushState(stateInObject)
+		return stateInObject
+	case l.Accept("["):
+		l.Emit(LArrayStart)
+		l.PushState(stateInObject)
+		return stateInArray
+	}
+	return l.Errorf("Unknown token: %s", string(l.Peek()))
+}
+
+func stateInArray(l *Lexer) stateFunc {
+	ignoreWhiteSpace(l)
+	l.Accept(",")
+	ignoreWhiteSpace(l)
+	switch {
+	case scanQuotedString(l, '"'):
+		l.Emit(LString)
+	case scanNumber(l):
+		l.Emit(LNumber)
+	case l.AcceptAnyOf([]string{"true", "false"}, true):
+		l.Emit(LBoolean)
+	case l.AcceptString("null", true):
+		l.Emit(LNull)
+	case l.Accept("{"):
+		l.Emit(LObjectStart)
+		l.PushState(stateInArray)
+		return stateInObject
+	case l.Accept("["):
+		l.Emit(LArrayStart)
+		l.PushState(stateInArray)
+		return stateInArray
+	case l.Accept("]"):
+		l.Emit(LArrayEnd)
+		return l.PopState()
+	}
+	return stateInArray
+}
+
+func ignoreWhiteSpace(l *Lexer) {
+	l.AcceptWhile(" \n\t") // ignore whitespaces
+	l.Ignore()
+}