More intuitive version matching

Avoids many issues with regex and glob patterns in version arguments
matching incorrectly. Prevents invalid versions being requested from
remote source. Always provides opportunity to confirm version being
installed.

Signed-off-by: Roy-Orbison <Roy-Orbison@users.noreply.github.com>

Author: Roy-Orbison

ubuntu-mainline-kernel.sh

@@ -369,6 +369,20 @@ latest_local_version() {
 }
 
 remote_html_cache=""
+remote_versions_read=0
+
+normalize_version_for_match() {
+    local version="$1"
+    if [[ -n "$version" && ! "$version" =~ [*] ]]; then
+        # not already a glob pattern
+        if [[ ! "$version" =~ ^v ]]; then
+            version="v$version"
+        fi
+        version="${version%.}"
+    fi
+    echo "$version"
+}
+
 parse_remote_versions() {
     local line
     while read -r line; do
@@ -389,34 +403,41 @@ parse_remote_versions() {
 load_remote_versions () {
     local line
 
-    [[ -n "$2" ]] && {
-      REMOTE_VERSIONS=()
+    [[ -n "$1" ]] && {
+        remote_versions_read=0
     }
 
-    if [ ${#REMOTE_VERSIONS[@]} -eq 0 ]; then
+    if [ $remote_versions_read -eq 0 ]; then
+        REMOTE_VERSIONS=()
         if [ -z "$remote_html_cache" ]; then
-          [ -z "$1" ] && logn "Downloading index from $ppa_host"
+          [ -z "$2" ] && logn "Downloading index from $ppa_host"
           remote_html_cache=$(download $ppa_host $ppa_index)
-          [ -z "$1" ] && log
+          [ -z "$2" ] && log
         fi
 
+        version_for_match="$(normalize_version_for_match "$1")"
         IFS=$'\n'
         while read -r line; do
+            (( remote_versions_read++ ))
             # reinstate original rc suffix join character
             if [[ $line =~ ^([^~]+)~([^~]+)$ ]]; then
                 [[ $use_rc -eq 0 ]] && continue
                 line="${BASH_REMATCH[1]}-${BASH_REMATCH[2]}"
             fi
-            [[ -n "$2" ]] && [[ ! "$line" =~ $2 ]] && continue
-            REMOTE_VERSIONS+=("$line")
+            # shellcheck disable=SC2053
+            if [[ -z "$version_for_match" ]] || \
+                [[ "$line" == $version_for_match || "$line" == $version_for_match.* || "$line" == $version_for_match-* ]]
+            then
+                REMOTE_VERSIONS+=("$line")
+            fi
         done < <(parse_remote_versions | sort -V)
         unset IFS
     fi
 }
 
 latest_remote_version () {
-    load_remote_versions 1 "$1"
-    echo "${REMOTE_VERSIONS[${#REMOTE_VERSIONS[@]}-1]}"
+    load_remote_versions "$1" 1
+    [[ ${#REMOTE_VERSIONS[@]} -gt 0 ]] && echo "${REMOTE_VERSIONS[${#REMOTE_VERSIONS[@]}-1]}"
 }
 
 check_environment () {
@@ -430,7 +451,7 @@ guard_run_as_root () {
   if [ "$(id -u)" -ne 0 ]; then
     echo "The '$run_action' command requires root privileges"
     exit 2
-  fi  
+  fi
 }
 
 # execute requested action
@@ -535,15 +556,13 @@ Optional:
         ;;
     remote-list)
         check_environment
-        load_remote_versions
+        load_remote_versions "${action_data[0]}"
 
         # shellcheck disable=SC2015
         [[ -n "$(command -v column)" ]] && { column="column -x"; } || { column="cat"; }
 
         (for version in "${REMOTE_VERSIONS[@]}"; do
-            if [ -z "${action_data[0]}" ] || [[ "$version" =~ ${action_data[0]} ]]; then
-                echo "$version"
-            fi
+            echo "$version"
         done) | $column
         ;;
     install)
@@ -558,42 +577,37 @@ Optional:
             version=$(latest_remote_version)
             log
 
-            if containsElement "$version" "${LOCAL_VERSIONS[@]}"; then
-                logn "Latest version is $version but seems its already installed"
-            else
-                logn "Latest version is: $version"
-            fi
-
-            if [ $do_install -gt 0 ] && [ $assume_yes -eq 0 ];then
-                logn ", continue? (y/N) "
-                [ $quiet -eq 0 ] && read -rsn1 continue
-                log
+            [[ -z "$version" ]] && {
+                err "No readable versions found"
+                exit 2
+            }
 
-                [ "$continue" != "y" ] && [ "$continue" != "Y" ] && { exit 0; }
-            else
-                log
-            fi
+            logn "Latest version is $version"
         else
-            load_remote_versions
+            load_remote_versions "${action_data[0]}"
 
-            version=""
-            if containsElement "v${action_data[0]#v}" "${REMOTE_VERSIONS[@]}"; then
-                version="v"${action_data[0]#v}
-            fi
+            version=$(latest_remote_version)
 
             [[ -z "$version" ]] && {
                 err "Version '${action_data[0]}' not found"
                 exit 2
             }
             shift
 
-            if [ $do_install -gt 0 ] && containsElement "$version" "${LOCAL_VERSIONS[@]}" && [ $assume_yes -eq 0 ]; then
-                logn "It seems version $version is already installed, continue? (y/N) "
-                [ $quiet -eq 0 ] && read -rsn1 continue
-                log
+            logn "Specified version matches $version"
+        fi
 
-                [ "$continue" != "y" ] && [ "$continue" != "Y" ] && { exit 0; }
-            fi
+        if containsElement "$version" "${LOCAL_VERSIONS[@]}"; then
+            logn " but it seems it's already installed"
+        fi
+        if [ $do_install -gt 0 ] && [ $assume_yes -eq 0 ];then
+            logn ", continue? (y/N) "
+            [ $quiet -eq 0 ] && read -rsn1 continue
+            log
+
+            [ "$continue" != "y" ] && [ "$continue" != "Y" ] && { exit 0; }
+        else
+            log
         fi
 
         [ ! -d "$workdir" ] && {