initial commit

customer/customer_attributes.go

@@ -0,0 +1,70 @@
+package customer
+
+import (
+	"errors"
+	"fmt"
+	"go-nkode/models"
+	"go-nkode/util"
+)
+
+// TODO: make generic
+type CustomerAttributes struct {
+	AttrVals   []uint64
+	SetVals    []uint64
+	keypadSize models.KeypadSize
+}
+
+func NewCustomerAttributes(keypadSize models.KeypadSize) (*CustomerAttributes, error) {
+	if keypadSize.IsDispersable() {
+		return nil, errors.New("number of keys must be less than the number of attributes per key to be dispersion resistant")
+	}
+
+	attrVals, errAttr := util.GenerateRandomNonRepeatingUint64(keypadSize.TotalAttrs())
+	if errAttr != nil {
+		return nil, errAttr
+	}
+	setVals, errSet := util.GenerateRandomNonRepeatingUint64(keypadSize.AttrsPerKey)
+	if errSet != nil {
+		return nil, errSet
+	}
+
+	customerAttrs := CustomerAttributes{
+		AttrVals:   attrVals,
+		SetVals:    setVals,
+		keypadSize: keypadSize,
+	}
+	return &customerAttrs, nil
+}
+
+func (c *CustomerAttributes) Renew() error {
+	attrVals, errAttr := util.GenerateRandomNonRepeatingUint64(c.keypadSize.TotalAttrs())
+	if errAttr != nil {
+		return errAttr
+	}
+	setVals, errSet := util.GenerateRandomNonRepeatingUint64(c.keypadSize.AttrsPerKey)
+	if errSet != nil {
+		return errSet
+	}
+	c.AttrVals = attrVals
+	c.SetVals = setVals
+	return nil
+}
+
+func (c *CustomerAttributes) IndexOfAttr(attrVal uint64) int {
+	// TODO: should this be mapped instead?
+	return util.IndexOf[uint64](c.AttrVals, attrVal)
+}
+
+func (c *CustomerAttributes) IndexOfSet(setVal uint64) int {
+	// TODO: should this be mapped instead?
+	return util.IndexOf[uint64](c.SetVals, setVal)
+}
+
+func (c *CustomerAttributes) GetAttrSetVal(attrVal uint64) (uint64, error) {
+	indexOfAttr := c.IndexOfAttr(attrVal)
+	if indexOfAttr == -1 {
+		return 0, errors.New(fmt.Sprintf("No attribute %d", attrVal))
+	}
+	setIdx := indexOfAttr % c.keypadSize.AttrsPerKey
+	return c.SetVals[setIdx], nil
+}