Organize backend into product executable and shared Go modules

backend/shared/database/internal/builder/expression.go

@@ -0,0 +1,108 @@
+package builderimp
+
+import (
+	"reflect"
+
+	"git.sendico.io/tech/sxchnge/shared/database/repository/builder"
+	"go.mongodb.org/mongo-driver/v2/bson"
+)
+
+type literalExpression struct {
+	value any
+}
+
+func NewLiteralExpression(value any) builder.Expression {
+	return &literalExpression{value: value}
+}
+
+func (e *literalExpression) Build() any {
+	return bson.D{{Key: string(builder.Literal), Value: e.value}}
+}
+
+type variadicExpression struct {
+	op    builder.MongoOperation
+	parts []builder.Expression
+}
+
+func (e *variadicExpression) Build() any {
+	args := make([]any, 0, len(e.parts))
+	for _, p := range e.parts {
+		args = append(args, p.Build())
+	}
+	return bson.D{{Key: string(e.op), Value: args}}
+}
+
+func newVariadicExpression(op builder.MongoOperation, exprs ...builder.Expression) builder.Expression {
+	return &variadicExpression{
+		op:    op,
+		parts: exprs,
+	}
+}
+
+func newBinaryExpression(op builder.MongoOperation, left, right builder.Expression) builder.Expression {
+	return &variadicExpression{
+		op:    op,
+		parts: []builder.Expression{left, right},
+	}
+}
+
+type unaryExpression struct {
+	op  builder.MongoOperation
+	rhs builder.Expression
+}
+
+func (e *unaryExpression) Build() any {
+	return bson.D{{Key: string(e.op), Value: e.rhs.Build()}}
+}
+
+func newUnaryExpression(op builder.MongoOperation, right builder.Expression) builder.Expression {
+	return &unaryExpression{
+		op:  op,
+		rhs: right,
+	}
+}
+
+type matchExpression struct {
+	op  builder.MongoOperation
+	rhs builder.Expression
+}
+
+func (e *matchExpression) Build() any {
+	return bson.E{Key: string(e.op), Value: e.rhs.Build()}
+}
+
+func newMatchExpression(op builder.MongoOperation, right builder.Expression) builder.Expression {
+	return &matchExpression{
+		op:  op,
+		rhs: right,
+	}
+}
+
+func InRef(value builder.Field) builder.Expression {
+	return newMatchExpression(builder.In, NewValue(NewRefFieldImp(value).Build()))
+}
+
+type inImpl struct {
+	values []any
+}
+
+func (e *inImpl) Build() any {
+	return bson.D{{Key: string(builder.In), Value: e.values}}
+}
+
+func In(values ...any) builder.Expression {
+	var flattenedValues []any
+
+	for _, v := range values {
+		switch reflect.TypeOf(v).Kind() {
+		case reflect.Slice:
+			slice := reflect.ValueOf(v)
+			for i := range slice.Len() {
+				flattenedValues = append(flattenedValues, slice.Index(i).Interface())
+			}
+		default:
+			flattenedValues = append(flattenedValues, v)
+		}
+	}
+	return &inImpl{values: flattenedValues}
+}