1 files changed, 75 insertions, 0 deletions
diff --git a/pkg/commands/lrem.go b/pkg/commands/lrem.go
new file mode 100644
index 0000000..38be270
--- /dev/null
+++ b/pkg/commands/lrem.go
@@ -0,0 +1,75 @@
+package commands
+
+import (
+	"errors"
+	"redisClone/pkg/core"
+	"strconv"
+)
+
+func Lrem(args []string, getShard func(k string) *core.Shard) interface{} {
+	key := args[1]
+	count, err := strconv.Atoi(args[2])
+	toBeRemoved := args[3]
+	if err != nil {
+		return errors.New("value is not an integer")
+	}
+
+	s := getShard(key)
+	item, exists := s.Data[key]
+	if !exists {
+		return 0
+	}
+	list, ok := item.Value.([]string)
+	if !ok {
+		return errors.New("WRONGTYPE Operation against a key holding the wrong kind of value")
+	}
+
+	counter := 0
+	absCount := count
+	if count < 0 {
+		absCount = -count
+	}
+
+	var newList []string
+	if count == 0 {
+		newList = []string{}
+		for _, value := range list {
+			if value == toBeRemoved {
+				counter++
+			} else {
+				newList = append(newList, value)
+			}
+		}
+	} else if count > 0 {
+		newList = []string{}
+		for _, value := range list {
+			if value == toBeRemoved && counter < absCount {
+				counter++
+			} else {
+				newList = append(newList, value)
+			}
+		}
+	} else { // count < 0
+		reversedNewList := []string{}
+		for i := len(list) - 1; i >= 0; i-- {
+			value := list[i]
+			if value == toBeRemoved && counter < absCount {
+				counter++
+			} else {
+				reversedNewList = append(reversedNewList, value)
+			}
+		}
+		newList = make([]string, len(reversedNewList))
+		for i, v := range reversedNewList {
+			newList[len(reversedNewList)-1-i] = v
+		}
+	}
+
+	if len(newList) == 0 {
+		delete(s.Data, key)
+	} else {
+		item.Value = newList
+		s.Data[key] = item
+	}
+	return counter
+}