epm: implement list (with --available and --installed options)

bin/epm

@@ -278,6 +278,10 @@ check_command()
         epm_cmd=packages
         direct_args=1
         ;;
+    list)                     # HELPCMD: print list of packages
+        epm_cmd=list
+        direct_args=1
+        ;;
     # it is too hard operation, so just list name is very short for it
     list-available)           # HELPCMD: print list of all available packages
         epm_cmd=list_available

bin/epm-list

+#!/bin/sh
+#
+# Copyright (C) 2023  Etersoft
+# Copyright (C) 2023  Vitaly Lipatov <lav@etersoft.ru>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+
+epm_list_help()
+{
+    cat <<EOF
+epm list - list packages
+Usage: epm list [options] [package]
+
+Options:
+  --available           list only available packages
+  --installed           list only installed packages
+EOF
+#  --all                 list all packages (default)
+}
+
+epm_list()
+{
+    local option="$1"
+
+    if [ -z "$1" ] ; then
+        # locally installed packages by default
+        load_helper epm-packages
+        epm_packages "$@"
+        return
+    fi
+
+    shift
+
+    case "$option" in
+        -h|--help)
+            epm_list_help
+            return
+            ;;
+        #--all)
+        #    # TODO: exclude locally installed?
+        #    epm_list_available
+        #    return
+        #    ;;
+        --available)
+            # TODO: exclude locally installed?
+            load_helper epm-list_available
+            epm_list_available "$@"
+            return
+            ;;
+        --installed)
+            load_helper epm-packages
+            epm_packages "$@"
+            return
+            ;;
+        *)
+            fatal "Unknown option $option, use epm list --help to get info"
+            ;;
+    esac
+
+    epm_list_help >&2
+    fatal "Run with appropriate option"
+}