[perf] re-implement nvm_print_versions using awk

reducing `nvm ls-remote` from almost 20s to below 2s.

Signed-off-by: ryenus <ryenus@gmail.com>

nvm.sh

@@ -1642,88 +1642,86 @@ nvm_get_checksum() {
 }
 
 nvm_print_versions() {
-  local VERSION
-  local LTS
-  local FORMAT
   local NVM_CURRENT
-  local NVM_LATEST_LTS_COLOR
-  local NVM_OLD_LTS_COLOR
-
   local INSTALLED_COLOR
   local SYSTEM_COLOR
   local CURRENT_COLOR
   local NOT_INSTALLED_COLOR
   local DEFAULT_COLOR
-  local LTS_COLOR
+  local NVM_HAS_COLORS
 
+  NVM_CURRENT=$(nvm_ls_current)
   INSTALLED_COLOR=$(nvm_get_colors 1)
   SYSTEM_COLOR=$(nvm_get_colors 2)
   CURRENT_COLOR=$(nvm_get_colors 3)
   NOT_INSTALLED_COLOR=$(nvm_get_colors 4)
   DEFAULT_COLOR=$(nvm_get_colors 5)
-  LTS_COLOR=$(nvm_get_colors 6)
 
-  NVM_CURRENT=$(nvm_ls_current)
-  NVM_LATEST_LTS_COLOR=$(nvm_echo "${CURRENT_COLOR}" | command tr '0;' '1;')
-  NVM_OLD_LTS_COLOR="${DEFAULT_COLOR}"
-  local NVM_HAS_COLORS
   if [ -z "${NVM_NO_COLORS-}" ] && nvm_has_colors; then
     NVM_HAS_COLORS=1
   fi
-  local LTS_LENGTH
-  local LTS_FORMAT
-  nvm_echo "${1-}" \
-  | command sed '1!G;h;$!d' \
-  | command awk '{ if ($2 && $3 && $3 == "*") { print $1, "(Latest LTS: " $2 ")" } else if ($2) { print $1, "(LTS: " $2 ")" } else { print $1 } }' \
-  | command sed '1!G;h;$!d' \
-  | while read -r VERSION_LINE; do
-    VERSION="${VERSION_LINE%% *}"
-    LTS="${VERSION_LINE#* }"
-    FORMAT='%15s'
-    if [ "_${VERSION}" = "_${NVM_CURRENT}" ]; then
-      if [ "${NVM_HAS_COLORS-}" = '1' ]; then
-        FORMAT="\033[${CURRENT_COLOR}-> %12s\033[0m"
-      else
-        FORMAT='-> %12s *'
-      fi
-    elif [ "${VERSION}" = "system" ]; then
-      if [ "${NVM_HAS_COLORS-}" = '1' ]; then
-        FORMAT="\033[${SYSTEM_COLOR}%15s\033[0m"
-      else
-        FORMAT='%15s *'
-      fi
-    elif nvm_is_version_installed "${VERSION}"; then
-      if [ "${NVM_HAS_COLORS-}" = '1' ]; then
-        FORMAT="\033[${INSTALLED_COLOR}%15s\033[0m"
-      else
-        FORMAT='%15s *'
-      fi
-    fi
-    if [ "${LTS}" != "${VERSION}" ]; then
-      case "${LTS}" in
-        *Latest*)
-          LTS="${LTS##Latest }"
-          LTS_LENGTH="${#LTS}"
-          if [ "${NVM_HAS_COLORS-}" = '1' ]; then
-            LTS_FORMAT="  \\033[${NVM_LATEST_LTS_COLOR}%${LTS_LENGTH}s\\033[0m"
-          else
-            LTS_FORMAT="  %${LTS_LENGTH}s"
-          fi
-        ;;
-        *)
-          LTS_LENGTH="${#LTS}"
-          if [ "${NVM_HAS_COLORS-}" = '1' ]; then
-            LTS_FORMAT="  \\033[${NVM_OLD_LTS_COLOR}%${LTS_LENGTH}s\\033[0m"
-          else
-            LTS_FORMAT="  %${LTS_LENGTH}s"
-          fi
-        ;;
-      esac
-      command printf -- "${FORMAT}${LTS_FORMAT}\\n" "${VERSION}" " ${LTS}"
-    else
-      command printf -- "${FORMAT}\\n" "${VERSION}"
-    fi
-  done
+
+  awk -v _input="${1-}" -v _nvm_ls="$(nvm_ls)" -v current="$NVM_CURRENT" \
+    -v installed_color="$INSTALLED_COLOR" -v system_color="$SYSTEM_COLOR" \
+    -v current_color="$CURRENT_COLOR" -v default_color="$DEFAULT_COLOR" \
+    -v has_colors="$NVM_HAS_COLORS" '
+BEGIN {
+  fmt_installed  = has_colors ? ("\033[" installed_color "%15s\033[0m") : "%15s";
+  fmt_system     = has_colors ? ("\033[" system_color "%15s\033[0m")    : "%15s";
+  fmt_current    = has_colors ? ("\033[" current_color "->%13s\033[0m") : "->%13s";
+
+  latest_lts_color = current_color;
+  sub(/0;/, "1;", latest_lts_color);
+  fmt_latest_lts = has_colors ? ("\033[" latest_lts_color "(Latest LTS: %s)\033[0m") : "(Latest LTS: %s)";
+  fmt_old_lts    = has_colors ? ("\033[" default_color "(LTS: %s)\033[0m") : "(LTS: %s)";
+  fmt_aux[1]     = "   ";
+  fmt_aux[2]     = " * ";
+
+  split(_input, lines, "\n");
+  split(_nvm_ls, installed, "\n");
+  total = length(lines);
+
+  for (n = 1; n <= total; n++) {
+    split(lines[n], fields, /\s+/);
+
+    len = length(fields);
+    version = fields[1];
+    is_installed = 0;
+
+    for (i in installed) {
+      if (version == installed[i]) {
+        is_installed = 1;
+        break;
+      }
+    }
+
+    fmt_version = "%15s";
+    if (version == current) {
+      fmt_version = fmt_current;
+    } else if (version == "system") {
+      fmt_version = fmt_system;
+    } else if (is_installed) {
+      fmt_version = fmt_installed;
+    }
+
+    aux = (!has_colors && is_installed) + 1;
+    if (len == 1) {
+      formatted = sprintf(fmt_version, version);
+    } else if (len == 2) {
+      formatted = sprintf((fmt_version fmt_aux[aux] fmt_old_lts), version, fields[2]);
+    } else if (len == 3 && fields[3] == "*") {
+      formatted = sprintf((fmt_version fmt_aux[aux] fmt_latest_lts), version, fields[2]);
+    }
+
+    output[n] = formatted;
+  }
+
+  for (n = 1; n <= total; n++) {
+    print output[n]
+  }
+
+  exit
+}'
 }
 
 nvm_validate_implicit_alias() {