feat(parsing): Overhaul query parser for extended OpenCypher syntax and block parsing

.gitignore

@@ -28,3 +28,5 @@ __debug*
 build/
 
 .DS_Store
+
+**ast*.json

go.mod

@@ -3,6 +3,7 @@ module github.com/OpenDgraph/Otter
 go 1.24.0
 
 require (
+	github.com/alecthomas/participle/v2 v2.1.4
 	github.com/dgraph-io/dgo/v240 v240.2.0
 	github.com/gorilla/websocket v1.5.3
 	github.com/hypermodeinc/dgraph/v24 v24.1.2

go.sum

@@ -49,8 +49,10 @@ github.com/HdrHistogram/hdrhistogram-go v1.1.2/go.mod h1:yDgFjdqOqDEKOvasDdhWNXY
 github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERoyfY=
 github.com/Microsoft/go-winio v0.6.2/go.mod h1:yd8OoFMLzJbo9gZq8j5qaps8bJ9aShtEA8Ipt1oGCvU=
 github.com/ajstarks/svgo v0.0.0-20180226025133-644b8db467af/go.mod h1:K08gAheRH3/J6wwsYMMT4xOr94bZjxIelGM0+d/wbFw=
-github.com/alecthomas/assert/v2 v2.10.0 h1:jjRCHsj6hBJhkmhznrCzoNpbA3zqy0fYiUcYZP/GkPY=
-github.com/alecthomas/assert/v2 v2.10.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
+github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0=
+github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
+github.com/alecthomas/participle/v2 v2.1.4 h1:W/H79S8Sat/krZ3el6sQMvMaahJ+XcM9WSI2naI7w2U=
+github.com/alecthomas/participle/v2 v2.1.4/go.mod h1:8tqVbpTX20Ru4NfYQgZf4mP18eXPTBViyMWiArNEgGI=
 github.com/alecthomas/repr v0.4.0 h1:GhI2A8MACjfegCPVq9f1FLvIBS+DrQ2KQBFZP1iFzXc=
 github.com/alecthomas/repr v0.4.0/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=

internal/parsing/cpAST.go

@@ -0,0 +1,138 @@
+package parsing
+
+import (
+	"github.com/alecthomas/participle/v2"
+	"github.com/alecthomas/participle/v2/lexer"
+)
+
+// ==================
+// AST
+// ==================
+
+type Query struct {
+	Match  *MatchClause  `parser:"\"MATCH\" @@"`
+	Create *CreateClause `parser:"[ \"CREATE\" @@ ]"`
+	Where  *WhereClause  `parser:"[ \"WHERE\" @@ ]"`
+	Return *ReturnClause `parser:"\"RETURN\" @@"`
+}
+
+// ==================
+// CREATE
+// ==================
+
+type CreateClause struct {
+	Patterns []*Pattern `parser:"@@ { \",\" @@ }"`
+}
+
+// ==================
+// MATCH
+// ==================
+
+type MatchClause struct {
+	Patterns []*Pattern `parser:"@@ { \",\" @@ }"`
+}
+
+type Pattern struct {
+	StartNode *NodePattern   `parser:"\"(\" @@ \")\""` // O padrão DEVE começar com um nó
+	Segments  []*PathSegment `parser:" { @@ } "`       // Segmentos de relação/nó subsequentes
+}
+
+type NodePattern struct {
+	Variable   string      `parser:"@Ident"`
+	Label      string      `parser:"[ \":\" @(Ident | Keyword) ]"`
+	Properties *Properties `parser:"[ @@ ]"` // Propriedades são opcionais e definidas em sua própria struct
+}
+
+type PathSegment struct {
+	Relationship *RelationshipPattern `parser:"@@"`             // Detalhes da relação (setas, tipo, alias)
+	EndNode      *NodePattern         `parser:"\"(\" @@ \")\""` // O nó no final deste segmento
+}
+
+type RelationshipPattern struct {
+	LeftArrow  string       `parser:"(@ArrowL | @Punct)"` // Captura '<-' ou '-' (Punct aqui DEVE ser '-')
+	Edge       *EdgePattern `parser:"\"[\" @@ \"]\""`     // Detalhes dentro dos colchetes
+	RightArrow string       `parser:"(@ArrowR | @Punct)"` // Captura '->' ou '-' (Punct aqui DEVE ser '-')
+}
+
+type EdgePattern struct {
+	Variable   string      `parser:"@Ident?"`          // Alias opcional (e.g., 'r' em [r:KNOWS])
+	Type       string      `parser:"[ \":\" @Ident ]"` // Tipo da relação (e.g., 'KNOWS')
+	Properties *Properties `parser:"[ @@ ]"`
+}
+
+type Properties struct {
+	Entries []*Property `parser:"\"{\" @@ { \",\" @@ } \"}\""`
+}
+
+type Property struct {
+	Key   string `parser:"@Ident \":\""`
+	Value string `parser:"@String"` // Por agora, apenas valores string. Poderia ser estendido.
+}
+
+// ==================
+// WHERE
+// ==================
+
+type WhereClause struct {
+	Cond *Condition `parser:"@@"`
+}
+
+type Condition struct {
+	Left     *PropertyAccess `parser:"@@"`
+	Operator string          `parser:"@Operator"`
+	Right    string          `parser:"@String"` // Ou outros tipos de valor
+}
+
+type PropertyAccess struct {
+	Object string `parser:"@Ident"`
+	Dot    string `parser:"@Punct"` // Captura o '.'
+	Field  string `parser:"@Ident"`
+}
+
+// ==================
+// RETURN
+// ==================
+type ReturnClause struct {
+	Fields []string `parser:"@Ident { \",\" @Ident }"`
+}
+
+// ==================
+// Custom Lexer
+// ==================
+
+var myLexer = lexer.MustSimple([]lexer.SimpleRule{
+	{Name: "Keyword", Pattern: `(?i)\b(MATCH|RETURN|WHERE|AND|OR|NOT|NULL|TRUE|FALSE|IN|IS|AS|WITH|UNWIND|OPTIONAL|DETACH|DELETE|SET|CREATE|MERGE|ON|CASE|WHEN|THEN|ELSE|DISTINCT|ORDER|BY|SKIP|LIMIT|ASC|DESC)\b`},
+	{Name: "ArrowL", Pattern: `<-`},
+	{Name: "ArrowR", Pattern: `->`},
+	{Name: "Ident", Pattern: `[a-zA-Z_][a-zA-Z0-9_]*`},
+	{Name: "String", Pattern: `'[^']*'|"[^"]*"`},
+	{Name: "Operator", Pattern: `<>|<=|>=|=|<|>`},
+	{Name: "Punct", Pattern: `[-:\[\]\(\),\{\}.]`},
+	{Name: "Whitespace", Pattern: `\s+`},
+	{Name: "comment", Pattern: `/\*.*?\*/`},
+	{Name: "line_comment", Pattern: `//[^\n]*`},
+})
+
+func BuildParser[T any](options ...participle.Option) *participle.Parser[T] {
+	defaultOptions := []participle.Option{
+		participle.Lexer(myLexer),
+		participle.Unquote("String"),
+		participle.Elide("Whitespace", "comment", "line_comment"),
+		participle.CaseInsensitive("Keyword"),
+		participle.UseLookahead(2),
+	}
+	return participle.MustBuild[T](append(defaultOptions, options...)...)
+}
+
+func BuildQueryParser(options ...participle.Option) *participle.Parser[Query] {
+	defaultOptions := []participle.Option{
+		participle.Lexer(myLexer),
+		participle.Unquote("String"),
+		participle.Elide("Whitespace", "comment", "line_comment"),
+		participle.CaseInsensitive("Keyword"),
+		participle.UseLookahead(2),
+	}
+	parser := participle.MustBuild[Query](append(defaultOptions, options...)...)
+
+	return parser
+}

internal/parsing/neo.go

@@ -0,0 +1,147 @@
+package parsing
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/alecthomas/participle/v2"
+)
+
+var (
+	matchParser  = mustBuildParser[MatchClause]()
+	whereParser  = mustBuildParser[WhereClause]()
+	returnParser = mustBuildParser[ReturnClause]()
+	createParser = mustBuildParser[CreateClause]()
+)
+
+func mustBuildParser[T any]() *participle.Parser[T] {
+	return BuildParser[T]()
+}
+
+func ParseMatchClause(src string) (*MatchClause, error) {
+	return matchParser.ParseString("", src)
+}
+
+func ParseWhereClause(src string) (*WhereClause, error) {
+	return whereParser.ParseString("", src)
+}
+
+func ParseReturnClause(src string) (*ReturnClause, error) {
+	return returnParser.ParseString("", src)
+}
+
+func ParseCreateClause(src string) (*CreateClause, error) {
+	return createParser.ParseString("", src)
+}
+
+// Full dispatcher for breaking a query into parts and parsing them
+func ParseQueryParts(query string) (*MatchClause, *WhereClause, *ReturnClause, error) {
+	query = strings.TrimSpace(query)
+	upper := strings.ToUpper(query)
+
+	switch {
+	case strings.HasPrefix(upper, "CREATE"):
+		createClause, err := ParseCreateClause(query)
+		if err != nil {
+			return nil, nil, nil, fmt.Errorf("create parse error: %w", err)
+		}
+		// Se quiser devolver CREATE como resultado exclusivo:
+		return nil, nil, nil, fmt.Errorf("CREATE clause parsed: %+v", createClause) // ou outro retorno que faça sentido
+
+	default:
+
+		matchIndex := strings.Index(query, "MATCH")
+		whereIndex := strings.Index(query, "WHERE")
+		returnIndex := strings.Index(query, "RETURN")
+
+		if matchIndex == -1 {
+			return nil, nil, nil, fmt.Errorf("invalid query: must start with MATCH")
+		}
+
+		if returnIndex == -1 {
+			return nil, nil, nil, fmt.Errorf("invalid query: must contain RETURN")
+		}
+
+		matchEnd := len(query)
+		if whereIndex != -1 {
+			matchEnd = whereIndex
+		} else if returnIndex != -1 {
+			matchEnd = returnIndex
+		}
+
+		matchPart := query[matchIndex+len("MATCH") : matchEnd]
+
+		var wherePart string
+		if whereIndex != -1 {
+			whereEnd := len(query)
+			if returnIndex != -1 && returnIndex > whereIndex {
+				whereEnd = returnIndex
+			} else if returnIndex != -1 && returnIndex < whereIndex {
+				return nil, nil, nil, fmt.Errorf("invalid query: RETURN cannot come before WHERE")
+			}
+			wherePart = query[whereIndex+len("WHERE") : whereEnd]
+		}
+
+		var returnPart string
+		if returnIndex != -1 {
+			returnPart = query[returnIndex+len("RETURN"):]
+		} else {
+			return nil, nil, nil, fmt.Errorf("invalid query: must contain RETURN")
+		}
+
+		matchClause, err := ParseMatchClause(matchPart)
+		if err != nil {
+			return nil, nil, nil, fmt.Errorf("match parse error: %w", err)
+		}
+
+		var whereClause *WhereClause
+		if wherePart != "" {
+			whereClause, err = ParseWhereClause(wherePart)
+			if err != nil {
+				return nil, nil, nil, fmt.Errorf("where parse error: %w", err)
+			}
+		}
+
+		returnClause, err := ParseReturnClause(returnPart)
+		if err != nil {
+			return nil, nil, nil, fmt.Errorf("return parse error: %w", err)
+		}
+
+		return matchClause, whereClause, returnClause, nil
+	}
+}
+
+type ASTSnapshot struct {
+	Test  string      `json:"test"`
+	Input string      `json:"input"`
+	AST   interface{} `json:"ast"`
+}
+
+func saveASTSnapshot(t *testing.T, snapshot ASTSnapshot, path string) {
+	t.Helper()
+
+	dir := filepath.Dir(path)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		t.Fatalf("failed to create directory %s: %v", dir, err)
+	}
+
+	var snapshots []ASTSnapshot
+	if data, err := os.ReadFile(path); err == nil {
+		_ = json.Unmarshal(data, &snapshots)
+	}
+
+	snapshots = append(snapshots, snapshot)
+
+	data, err := json.MarshalIndent(snapshots, "", "  ")
+	if err != nil {
+		t.Fatalf("failed to marshal snapshot: %v", err)
+	}
+
+	if err := os.WriteFile(path, data, 0644); err != nil {
+		t.Fatalf("failed to write snapshot file: %v", err)
+	}
+}