feat(command): add dispatch and setrange to keyspace

lib/excache/command/keyspace.ex

@@ -156,3 +156,159 @@ defmodule Excache.Command.Keyspace do
   def dispatch("RENAME", [source, dest], state),
     do: reply(statusReply(Store.rename(source, dest)), state)
 
+  def dispatch("RENAMENX", [source, dest], state),
+    do: reply(integerReply(Store.renamenx(source, dest)), state)
+
+  def dispatch("COPY", [source, dest | rest], state) do
+    case parseCopyOptions(rest, false) do
+      {:ok, _replace} when source == dest ->
+        reply({:error, "ERR source and destination objects are the same"}, state)
+
+      {:ok, replace} ->
+        reply(integerReply(Store.copy(source, dest, replace)), state)
+
+      {:reply, term} ->
+        reply(term, state)
+    end
+  end
+
+  def dispatch("TOUCH", [_ | _] = keys, state), do: reply({:integer, Store.touch(keys)}, state)
+  def dispatch("UNLINK", [_ | _] = keys, state), do: reply({:integer, Store.del(keys)}, state)
+
+  def dispatch("EXPIREAT", [key, secondsRaw | rest], state) do
+    case Integer.parse(secondsRaw) do
+      {seconds, ""} ->
+        case parseExpireFlags(rest) do
+          {:ok, flags} -> reply({:integer, expireAt(key, seconds * 1000, flags)}, state)
+          {:reply, term} -> reply(term, state)
+        end
+
+      _ ->
+        reply(Reply.not_integer(), state)
+    end
+  end
+
+  def dispatch("EXPIRETIME", [key], state),
+    do: reply({:integer, Store.expiretime(key, :seconds)}, state)
+
+  def dispatch("PEXPIRETIME", [key], state),
+    do: reply({:integer, Store.expiretime(key, :milliseconds)}, state)
+
+  def dispatch(_name, _args, _state), do: :unhandled
+
+  defp setrange(key, _offset, ""), do: integerReply(Store.strlen(key))
+  defp setrange(key, offset, value), do: integerReply(Store.setrange(key, offset, value))
+
+  defp lpos(key, element, %{count: nil} = options, state) do
+    case Store.lpos(key, element, options.rank, 1, options.maxlen) do
+      {:ok, []} -> reply({:bulk, nil}, state)
+      {:ok, [index]} -> reply({:integer, index}, state)
+      {:error, reason} -> reply(errorTerm(reason), state)
+    end
+  end
+
+  defp lpos(key, element, options, state) do
+    case Store.lpos(key, element, options.rank, options.count, options.maxlen) do
+      {:ok, indexes} -> reply({:array, Enum.map(indexes, &{:integer, &1})}, state)
+      {:error, reason} -> reply(errorTerm(reason), state)
+    end
+  end
+
+  defp parseLposOptions([], options), do: {:ok, options}
+
+  defp parseLposOptions([token | rest], options) do
+    case {String.upcase(token), rest} do
+      {"RANK", [raw | tail]} ->
+        case Integer.parse(raw) do
+          {0, ""} -> {:reply, {:error, rankZeroMessage()}}
+          {rank, ""} -> parseLposOptions(tail, %{options | rank: rank})
+          _ -> {:reply, Reply.not_integer()}
+        end
+
+      {"COUNT", [raw | tail]} ->
+        case Integer.parse(raw) do
+          {count, ""} when count >= 0 -> parseLposOptions(tail, %{options | count: count})
+          {_negative, ""} -> {:reply, {:error, "ERR COUNT can't be negative"}}
+          _ -> {:reply, Reply.not_integer()}
+        end
+
+      {"MAXLEN", [raw | tail]} ->
+        case Integer.parse(raw) do
+          {maxlen, ""} when maxlen >= 0 -> parseLposOptions(tail, %{options | maxlen: maxlen})
+          {_negative, ""} -> {:reply, {:error, "ERR MAXLEN can't be negative"}}
+          _ -> {:reply, Reply.not_integer()}
+        end
+
+      _ ->
+        {:reply, Reply.syntax()}
+    end
+  end
+
+  defp rankZeroMessage do
+    "ERR RANK can't be zero. Use 1 to start searching from the first matching element in the " <>
+      "head of the list or -1 searching backward from the tail of the list"
+  end
+
+  defp object("ENCODING", [key], state) do
+    withEntry(key, state, fn entry -> {:bulk, encodingName(entry)} end)
+  end
+
+  defp object("REFCOUNT", [key], state) do
+    withEntry(key, state, fn entry -> {:integer, refcount(entry)} end)
+  end
+
+  defp object("IDLETIME", [key], state) do
+    withEntry(key, state, fn _entry -> {:integer, idleSeconds(key)} end)
+  end
+
+  defp object("HELP", [], state) do
+    lines = [
+      "OBJECT <subcommand> <key>. Subcommands are:",
+      "ENCODING <key>",
+      "    Return the kind of internal representation used to store the value of <key>.",
+      "IDLETIME <key>",
+      "    Return the seconds since <key> was last accessed, or 0 when the current",
+      "    maxmemory-policy keeps no access metadata for it.",
+      "REFCOUNT <key>",
+      "    Return the number of references of the value associated with <key>.",
+      "HELP",
+      "    Print this help."
+    ]
+
+    reply({:array, Enum.map(lines, &{:simple, &1})}, state)
+  end
+
+  defp object(subcommand, _rest, state) do
+    message =
+      "ERR Unknown subcommand or wrong number of arguments for '#{subcommand}'. " <>
+        "Try OBJECT HELP."
+
+    reply({:error, message}, state)
+  end
+
+  defp idleSeconds(key) do
+    case Tracker.idleMs(Tracker, key, System.system_time(:millisecond)) do
+      nil -> 0
+      idleMs -> div(idleMs, 1000)
+    end
+  end
+
+  defp withEntry(key, state, fun) do
+    case Store.encoding(key) do
+      nil -> reply({:error, "ERR no such key"}, state)
+      {:ok, entry} -> reply(fun.(entry), state)
+    end
+  end
+
+  defp encodingName({:string, value, _ea}) do
+    cond do
+      integerString?(value) -> "int"
+      byte_size(value) <= 44 -> "embstr"
+      true -> "raw"
+    end
+  end
+
+  defp encodingName({:list, value, _ea}) do
+    if compact?(value, length(value)), do: "listpack", else: "quicklist"
+  end
+