sub/command optarg parser refurbished from Tomb

zuper

@@ -704,6 +704,7 @@ EOF
     func "$_num key/values stored in $_path"
 }
 
+
 # }}} Key/Value filesave
 
 # {{{ Get/Set REST API
@@ -845,6 +846,155 @@ EOF
 
 # }}} Get/Set REST API
 
+# {{{ Parse commandline options
+
+# for example usage, see Tomb http://tomb.dyne.org
+vars+=(subcommand)
+arrs+=(option_main option_params)
+maps+=(option option_subcommands)
+
+# Hi, dear developer!  Are you trying to add a new subcommand, or
+# to add some options?  Well, keep in mind that option names are
+# global: they cannot bear a different meaning or behaviour across
+# subcommands.  The only exception is "-o" which means: "options
+# passed to the local subcommand", and thus can bear a different
+# meaning for different subcommands.
+#
+# For example, "-s" means "size" and accepts one argument. If you
+# are tempted to add an alternate option "-s" (e.g., to mean
+# "silent", and that doesn't accept any argument) DON'T DO IT!
+#
+# There are two reasons for that:
+#    I. Usability; users expect that "-s" is "size"
+#   II. Option parsing WILL EXPLODE if you do this kind of bad
+#       things (it will complain: "option defined more than once")
+#
+# If you want to use the same option in multiple commands then you
+# can only use the non-abbreviated long-option version like:
+# -force and NOT -f
+
+option.is_set() {
+
+	# Check whether a commandline option is set.
+	#
+	# Synopsis: option_is_set -flag [out]
+	#
+	# First argument is the commandline flag (e.g., "-s").
+	# If the second argument is present and set to 'out', print out the
+	# result: either 'set' or 'unset' (useful for if conditions).
+	#
+	# Return 0 if is set, 1 otherwise
+    local -i r   # the return code (0 = set, 1 = unset)
+
+    [[ -n ${(k)option[$1]} ]];
+    r=$?
+
+    [[ $2 == "out" ]] && {
+        [[ $r == 0 ]] && { print 'set' } || { print 'unset' }
+    }
+
+    return $r;
+}
+# Print the option value matching the given flag
+# Unique argument is the commandline flag (e.g., "-s").
+option.value() {
+    print -n - "${option[$1]}"
+}
+option.parse() {
+
+    ### Detect subcommand
+    local -aU every_opts #every_opts behave like a set; that is, an array with unique elements
+    for optspec in ${option_subcommands}${option_main}; do
+        for opt in ${=optspec}; do
+            every_opts+=${opt}
+        done
+    done
+    local -a oldstar
+    oldstar=("${(@)argv}")
+    #### detect early: useful for --option-parsing
+    zparseopts -M -D -Adiscardme ${every_opts}
+    if [[ -n ${(k)discardme[--option-parsing]} ]]; then
+        print $1
+        if [[ -n "$1" ]]; then
+            return 1
+        fi
+        return 0
+    fi
+    unset discardme
+    if ! zparseopts -M -E -D -Adiscardme ${every_opts}; then
+        _failure "Error parsing."
+        return 127
+    fi
+    unset discardme
+    subcommand=${1}
+    if [[ -z $subcommand ]]; then
+        subcommand="__default"
+    fi
+
+    if [[ -z ${(k)option_subcommands[$subcommand]} ]]; then
+        _warning "There's no such command \"::1 subcommand::\"." $subcommand
+        exitv=127 _failure "Please try -h for help."
+    fi
+    argv=("${(@)oldstar}")
+    unset oldstar
+
+    ### Parsing global + command-specific options
+    # zsh magic: ${=string} will split to multiple arguments when spaces occur
+    set -A cmd_opts ${option_main} ${=option_subcommands[$subcommand]}
+    # if there is no option, we don't need parsing
+    if [[ -n $cmd_opts ]]; then
+        zparseopts -M -E -D -Aoption ${cmd_opts}
+        if [[ $? != 0 ]]; then
+            _warning "Some error occurred during option processing."
+            exitv=127 _failure "See \"sdk help\" for more info."
+        fi
+    fi
+    #build option_params (array of arguments) and check if there are unrecognized options
+    ok=0
+    option_params=()
+    for arg in $*; do
+        if [[ $arg == '--' || $arg == '-' ]]; then
+            ok=1
+            continue #it shouldn't be appended to option_params
+        elif [[ $arg[1] == '-'  ]]; then
+            if [[ $ok == 0 ]]; then
+                exitv=127 _failure "Unrecognized option ::1 arg:: for subcommand ::2 subcommand::" $arg $subcommand
+            fi
+        fi
+        option_params+=$arg
+    done
+    # First parameter actually is the subcommand: delete it and shift
+    [[ $subcommand != '__default' ]] && { option_params[1]=(); shift }
+
+    ### End parsing command-specific options
+
+    [[ "$option_params" == "" ]] && {
+        func "sdk command: ::1 subcommand::" $subcommand
+    } || {
+        func "sdk command: ::1 subcommand:: ::2 param::" $subcommand $option_params
+    }
+
+}
+
+# Later: process subcommand
+# case "$subcommand" in
+# 	help)
+# 		print "TODO: help"
+# 		;;
+# 	__default)
+# 		zdump
+# 		;;
+
+#     # Reject unknown command and suggest help
+#     *)
+#         _warning "Command \"::1 subcommand::\" not recognized." $subcommand
+#         _message "Try -h for help."
+#         return 1
+#         ;;
+# esac
+
+# }}}
+
 # {{{ Helpers
 
 function helper.isfound isfound() {