feat(spectypes): add PostgreSQL array types and parsing functions

pkg/spectypes/sql_array_types.go

@@ -0,0 +1,755 @@
+package spectypes
+
+import (
+	"database/sql/driver"
+	"encoding/json"
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/google/uuid"
+)
+
+// parsePostgresArrayElements parses a PostgreSQL array literal (e.g. `{a,"b,c",d}`)
+// into a slice of raw string elements. Each element retains its unquoted/unescaped value.
+func parsePostgresArrayElements(s string) ([]string, error) {
+	s = strings.TrimSpace(s)
+	if s == "" || strings.EqualFold(s, "null") || strings.EqualFold(s, "NULL") {
+		return nil, nil
+	}
+	if !strings.HasPrefix(s, "{") || !strings.HasSuffix(s, "}") {
+		return nil, fmt.Errorf("not a valid PostgreSQL array literal: %q", s)
+	}
+	inner := s[1 : len(s)-1]
+	if inner == "" {
+		return []string{}, nil
+	}
+
+	var result []string
+	var cur strings.Builder
+	inQuotes := false
+	i := 0
+	for i < len(inner) {
+		c := inner[i]
+		switch {
+		case c == '"' && !inQuotes:
+			inQuotes = true
+		case c == '"' && inQuotes:
+			if i+1 < len(inner) && inner[i+1] == '"' {
+				cur.WriteByte('"')
+				i++
+			} else {
+				inQuotes = false
+			}
+		case c == '\\' && inQuotes:
+			if i+1 < len(inner) {
+				cur.WriteByte(inner[i+1])
+				i++
+			}
+		case c == ',' && !inQuotes:
+			result = append(result, cur.String())
+			cur.Reset()
+		default:
+			cur.WriteByte(c)
+		}
+		i++
+	}
+	result = append(result, cur.String())
+	return result, nil
+}
+
+// formatPostgresStringArray formats a []string back into a PostgreSQL array literal.
+func formatPostgresStringArray(vals []string) string {
+	if vals == nil {
+		return "NULL"
+	}
+	parts := make([]string, len(vals))
+	for i, v := range vals {
+		// Quote if value contains comma, double-quote, backslash, braces, whitespace, or is empty.
+		needsQuote := v == "" || strings.ContainsAny(v, `,"\\{}` + "\t\n\r ")
+		if needsQuote {
+			v = strings.ReplaceAll(v, `\`, `\\`)
+			v = strings.ReplaceAll(v, `"`, `""`)
+			parts[i] = `"` + v + `"`
+		} else {
+			parts[i] = v
+		}
+	}
+	return "{" + strings.Join(parts, ",") + "}"
+}
+
+// ── SqlStringArray ───────────────────────────────────────────────────────────
+
+// SqlStringArray is a nullable PostgreSQL text[] / varchar[] array.
+type SqlStringArray struct {
+	Val   []string
+	Valid bool
+}
+
+func (a *SqlStringArray) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlStringArray: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = elems
+	a.Valid = true
+	return nil
+}
+
+func (a SqlStringArray) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	return formatPostgresStringArray(a.Val), nil
+}
+
+func (a SqlStringArray) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlStringArray) UnmarshalJSON(b []byte) error {
+	s := strings.TrimSpace(string(b))
+	if s == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []string
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlStringArray(v []string) SqlStringArray {
+	return SqlStringArray{Val: v, Valid: true}
+}
+
+// ── SqlInt16Array ────────────────────────────────────────────────────────────
+
+type SqlInt16Array struct {
+	Val   []int16
+	Valid bool
+}
+
+func (a *SqlInt16Array) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlInt16Array: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = make([]int16, len(elems))
+	for i, e := range elems {
+		n, err := strconv.ParseInt(strings.TrimSpace(e), 10, 16)
+		if err != nil {
+			return fmt.Errorf("SqlInt16Array: element %d %q: %w", i, e, err)
+		}
+		a.Val[i] = int16(n)
+	}
+	a.Valid = true
+	return nil
+}
+
+func (a SqlInt16Array) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(a.Val))
+	for i, v := range a.Val {
+		parts[i] = strconv.FormatInt(int64(v), 10)
+	}
+	return "{" + strings.Join(parts, ",") + "}", nil
+}
+
+func (a SqlInt16Array) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlInt16Array) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []int16
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlInt16Array(v []int16) SqlInt16Array {
+	return SqlInt16Array{Val: v, Valid: true}
+}
+
+// ── SqlInt32Array ────────────────────────────────────────────────────────────
+
+type SqlInt32Array struct {
+	Val   []int32
+	Valid bool
+}
+
+func (a *SqlInt32Array) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlInt32Array: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = make([]int32, len(elems))
+	for i, e := range elems {
+		n, err := strconv.ParseInt(strings.TrimSpace(e), 10, 32)
+		if err != nil {
+			return fmt.Errorf("SqlInt32Array: element %d %q: %w", i, e, err)
+		}
+		a.Val[i] = int32(n)
+	}
+	a.Valid = true
+	return nil
+}
+
+func (a SqlInt32Array) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(a.Val))
+	for i, v := range a.Val {
+		parts[i] = strconv.FormatInt(int64(v), 10)
+	}
+	return "{" + strings.Join(parts, ",") + "}", nil
+}
+
+func (a SqlInt32Array) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlInt32Array) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []int32
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlInt32Array(v []int32) SqlInt32Array {
+	return SqlInt32Array{Val: v, Valid: true}
+}
+
+// ── SqlInt64Array ────────────────────────────────────────────────────────────
+
+type SqlInt64Array struct {
+	Val   []int64
+	Valid bool
+}
+
+func (a *SqlInt64Array) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlInt64Array: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = make([]int64, len(elems))
+	for i, e := range elems {
+		n, err := strconv.ParseInt(strings.TrimSpace(e), 10, 64)
+		if err != nil {
+			return fmt.Errorf("SqlInt64Array: element %d %q: %w", i, e, err)
+		}
+		a.Val[i] = n
+	}
+	a.Valid = true
+	return nil
+}
+
+func (a SqlInt64Array) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(a.Val))
+	for i, v := range a.Val {
+		parts[i] = strconv.FormatInt(v, 10)
+	}
+	return "{" + strings.Join(parts, ",") + "}", nil
+}
+
+func (a SqlInt64Array) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlInt64Array) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []int64
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlInt64Array(v []int64) SqlInt64Array {
+	return SqlInt64Array{Val: v, Valid: true}
+}
+
+// ── SqlFloat32Array ──────────────────────────────────────────────────────────
+
+type SqlFloat32Array struct {
+	Val   []float32
+	Valid bool
+}
+
+func (a *SqlFloat32Array) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlFloat32Array: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = make([]float32, len(elems))
+	for i, e := range elems {
+		f, err := strconv.ParseFloat(strings.TrimSpace(e), 32)
+		if err != nil {
+			return fmt.Errorf("SqlFloat32Array: element %d %q: %w", i, e, err)
+		}
+		a.Val[i] = float32(f)
+	}
+	a.Valid = true
+	return nil
+}
+
+func (a SqlFloat32Array) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(a.Val))
+	for i, v := range a.Val {
+		parts[i] = strconv.FormatFloat(float64(v), 'f', -1, 32)
+	}
+	return "{" + strings.Join(parts, ",") + "}", nil
+}
+
+func (a SqlFloat32Array) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlFloat32Array) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []float32
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlFloat32Array(v []float32) SqlFloat32Array {
+	return SqlFloat32Array{Val: v, Valid: true}
+}
+
+// ── SqlFloat64Array ──────────────────────────────────────────────────────────
+
+type SqlFloat64Array struct {
+	Val   []float64
+	Valid bool
+}
+
+func (a *SqlFloat64Array) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlFloat64Array: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = make([]float64, len(elems))
+	for i, e := range elems {
+		f, err := strconv.ParseFloat(strings.TrimSpace(e), 64)
+		if err != nil {
+			return fmt.Errorf("SqlFloat64Array: element %d %q: %w", i, e, err)
+		}
+		a.Val[i] = f
+	}
+	a.Valid = true
+	return nil
+}
+
+func (a SqlFloat64Array) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(a.Val))
+	for i, v := range a.Val {
+		parts[i] = strconv.FormatFloat(v, 'f', -1, 64)
+	}
+	return "{" + strings.Join(parts, ",") + "}", nil
+}
+
+func (a SqlFloat64Array) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlFloat64Array) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []float64
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlFloat64Array(v []float64) SqlFloat64Array {
+	return SqlFloat64Array{Val: v, Valid: true}
+}
+
+// ── SqlBoolArray ─────────────────────────────────────────────────────────────
+
+type SqlBoolArray struct {
+	Val   []bool
+	Valid bool
+}
+
+func (a *SqlBoolArray) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlBoolArray: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = make([]bool, len(elems))
+	for i, e := range elems {
+		e = strings.ToLower(strings.TrimSpace(e))
+		a.Val[i] = e == "t" || e == "true" || e == "1" || e == "yes"
+	}
+	a.Valid = true
+	return nil
+}
+
+func (a SqlBoolArray) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(a.Val))
+	for i, v := range a.Val {
+		if v {
+			parts[i] = "t"
+		} else {
+			parts[i] = "f"
+		}
+	}
+	return "{" + strings.Join(parts, ",") + "}", nil
+}
+
+func (a SqlBoolArray) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlBoolArray) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []bool
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlBoolArray(v []bool) SqlBoolArray {
+	return SqlBoolArray{Val: v, Valid: true}
+}
+
+// ── SqlUUIDArray ─────────────────────────────────────────────────────────────
+
+type SqlUUIDArray struct {
+	Val   []uuid.UUID
+	Valid bool
+}
+
+func (a *SqlUUIDArray) Scan(value any) error {
+	if value == nil {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var s string
+	switch v := value.(type) {
+	case string:
+		s = v
+	case []byte:
+		s = string(v)
+	default:
+		return fmt.Errorf("SqlUUIDArray: cannot scan type %T", value)
+	}
+	elems, err := parsePostgresArrayElements(s)
+	if err != nil {
+		return err
+	}
+	a.Val = make([]uuid.UUID, len(elems))
+	for i, e := range elems {
+		u, err := uuid.Parse(strings.TrimSpace(e))
+		if err != nil {
+			return fmt.Errorf("SqlUUIDArray: element %d %q: %w", i, e, err)
+		}
+		a.Val[i] = u
+	}
+	a.Valid = true
+	return nil
+}
+
+func (a SqlUUIDArray) Value() (driver.Value, error) {
+	if !a.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(a.Val))
+	for i, v := range a.Val {
+		parts[i] = v.String()
+	}
+	return "{" + strings.Join(parts, ",") + "}", nil
+}
+
+func (a SqlUUIDArray) MarshalJSON() ([]byte, error) {
+	if !a.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(a.Val)
+}
+
+func (a *SqlUUIDArray) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		a.Valid = false
+		a.Val = nil
+		return nil
+	}
+	var vals []uuid.UUID
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	a.Val = vals
+	a.Valid = true
+	return nil
+}
+
+func NewSqlUUIDArray(v []uuid.UUID) SqlUUIDArray {
+	return SqlUUIDArray{Val: v, Valid: true}
+}
+
+// ── SqlVector ────────────────────────────────────────────────────────────────
+
+// SqlVector is a nullable pgvector `vector` type backed by []float32.
+// Wire format: `[1.0,2.0,3.0]` (square brackets, comma-separated floats).
+type SqlVector struct {
+	Val   []float32
+	Valid bool
+}
+
+func (v *SqlVector) Scan(value any) error {
+	if value == nil {
+		v.Valid = false
+		v.Val = nil
+		return nil
+	}
+	var s string
+	switch val := value.(type) {
+	case string:
+		s = val
+	case []byte:
+		s = string(val)
+	default:
+		return fmt.Errorf("SqlVector: cannot scan type %T", value)
+	}
+	s = strings.TrimSpace(s)
+	if !strings.HasPrefix(s, "[") || !strings.HasSuffix(s, "]") {
+		return fmt.Errorf("SqlVector: not a valid vector literal: %q", s)
+	}
+	inner := s[1 : len(s)-1]
+	if inner == "" {
+		v.Val = []float32{}
+		v.Valid = true
+		return nil
+	}
+	parts := strings.Split(inner, ",")
+	v.Val = make([]float32, len(parts))
+	for i, p := range parts {
+		f, err := strconv.ParseFloat(strings.TrimSpace(p), 32)
+		if err != nil {
+			return fmt.Errorf("SqlVector: element %d %q: %w", i, p, err)
+		}
+		v.Val[i] = float32(f)
+	}
+	v.Valid = true
+	return nil
+}
+
+func (v SqlVector) Value() (driver.Value, error) {
+	if !v.Valid {
+		return nil, nil
+	}
+	parts := make([]string, len(v.Val))
+	for i, f := range v.Val {
+		parts[i] = strconv.FormatFloat(float64(f), 'f', -1, 32)
+	}
+	return "[" + strings.Join(parts, ",") + "]", nil
+}
+
+func (v SqlVector) MarshalJSON() ([]byte, error) {
+	if !v.Valid {
+		return []byte("null"), nil
+	}
+	return json.Marshal(v.Val)
+}
+
+func (v *SqlVector) UnmarshalJSON(b []byte) error {
+	if strings.TrimSpace(string(b)) == "null" {
+		v.Valid = false
+		v.Val = nil
+		return nil
+	}
+	var vals []float32
+	if err := json.Unmarshal(b, &vals); err != nil {
+		return err
+	}
+	v.Val = vals
+	v.Valid = true
+	return nil
+}
+
+func NewSqlVector(val []float32) SqlVector {
+	return SqlVector{Val: val, Valid: true}
+}