[#26] *: Move pkg content to root

Signed-off-by: Angira Kekteeva <kira@nspcc.ru>

policy/encode.go

@@ -0,0 +1,141 @@
+package policy
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/nspcc-dev/neofs-api-go/pkg/netmap"
+)
+
+// Encode parses data of PlacementPolicy to a string.
+func Encode(p *netmap.PlacementPolicy) []string {
+	if p == nil {
+		return nil
+	}
+
+	var (
+		replicas  = p.Replicas()
+		selectors = p.Selectors()
+		filters   = p.Filters()
+	)
+
+	// 1 for container backup factor
+	result := make([]string, 0, len(replicas)+len(selectors)+len(filters)+1)
+
+	// first print replicas
+	encodeReplicas(replicas, &result)
+
+	// then backup factor
+	if backupFactor := p.ContainerBackupFactor(); backupFactor != 0 {
+		result = append(result, fmt.Sprintf("CBF %d", backupFactor))
+	}
+
+	// then selectors
+	encodeSelectors(selectors, &result)
+
+	// then filters
+	encodeFilters(filters, &result)
+
+	return result
+}
+
+func encodeReplicas(replicas []*netmap.Replica, dst *[]string) {
+	builder := new(strings.Builder)
+
+	for _, replica := range replicas {
+		builder.WriteString("REP ")
+		builder.WriteString(strconv.FormatUint(uint64(replica.Count()), 10))
+
+		if s := replica.Selector(); s != "" {
+			builder.WriteString(" IN ")
+			builder.WriteString(s)
+		}
+
+		*dst = append(*dst, builder.String())
+		builder.Reset()
+	}
+}
+
+func encodeSelectors(selectors []*netmap.Selector, dst *[]string) {
+	builder := new(strings.Builder)
+
+	for _, selector := range selectors {
+		builder.WriteString("SELECT ")
+		builder.WriteString(strconv.FormatUint(uint64(selector.Count()), 10))
+
+		if a := selector.Attribute(); a != "" {
+			builder.WriteString(" IN")
+
+			switch selector.Clause() {
+			case netmap.ClauseSame:
+				builder.WriteString(" SAME ")
+			case netmap.ClauseDistinct:
+				builder.WriteString(" DISTINCT ")
+			default:
+				builder.WriteString(" ")
+			}
+
+			builder.WriteString(a)
+		}
+
+		if f := selector.Filter(); f != "" {
+			builder.WriteString(" FROM ")
+			builder.WriteString(f)
+		}
+
+		if n := selector.Name(); n != "" {
+			builder.WriteString(" AS ")
+			builder.WriteString(n)
+		}
+
+		*dst = append(*dst, builder.String())
+		builder.Reset()
+	}
+}
+
+func encodeFilters(filters []*netmap.Filter, dst *[]string) {
+	builder := new(strings.Builder)
+
+	for _, filter := range filters {
+		builder.WriteString("FILTER ")
+
+		builder.WriteString(encodeFilter(filter))
+
+		*dst = append(*dst, builder.String())
+		builder.Reset()
+	}
+}
+
+func encodeFilter(filter *netmap.Filter) string {
+	builder := new(strings.Builder)
+	unspecified := filter.Operation() == 0
+
+	if k := filter.Key(); k != "" {
+		builder.WriteString(k)
+		builder.WriteString(" ")
+		builder.WriteString(filter.Operation().String())
+		builder.WriteString(" ")
+		builder.WriteString(filter.Value())
+	} else if n := filter.Name(); unspecified && n != "" {
+		builder.WriteString("@")
+		builder.WriteString(n)
+	}
+
+	for i, subfilter := range filter.InnerFilters() {
+		if i != 0 {
+			builder.WriteString(" ")
+			builder.WriteString(filter.Operation().String())
+			builder.WriteString(" ")
+		}
+
+		builder.WriteString(encodeFilter(subfilter))
+	}
+
+	if n := filter.Name(); n != "" && !unspecified {
+		builder.WriteString(" AS ")
+		builder.WriteString(n)
+	}
+
+	return builder.String()
+}