use zparseopts for options

2 files changed, 90 insertions, 122 deletions

diff --git a/Readme.md b/Readme.md
index d905eb7..9ac951c 100644
--- a/Readme.md
+++ b/Readme.md
@@ -12,26 +12,26 @@ files as painless as possible, with support for things like embedding
 subtitles, various dithering algorithms, cropping, and post-optimisation (via
 [gifsicle](https://www.lcdf.org/gifsicle/))
 
-just clone and run `make-gif -h` to get started!
+just clone and run `make-gif --help` to get started!
 
 examples
 ========
 
 some example usages and their outputs:
 
-`make-gif -o -s 36:18 -t 3 菊次郎の夏.mkv out.gif`
+`make-gif -o -s 36:18 -l 3 菊次郎の夏.mkv out.gif`
 
 ![default](examples/default.gif)
 
-`make-gif -or -s 36:18 -t 3 -c 64 -d bayer2 菊次郎の夏.mkv out.gif`
+`make-gif -or -s 36:18 -l 3 -c 64 -d bayer2 菊次郎の夏.mkv out.gif`
 
 ![c-64_d-bayer2_r](examples/c-64_d-bayer2_r.gif)
 
-`make-gif -o -s 36:18 -t 3 -c 8 -d bayer5 -f 15 -w 320 菊次郎の夏.mkv out.gif`
+`make-gif -o -s 36:18 -l 3 -c 8 -d bayer5 -f 15 -w 320 菊次郎の夏.mkv out.gif`
 
 ![c-8_d-bayer5_f-15](examples/c-8_d-bayer5_f-15_w-320.gif)
 
-`make-gif -o -s 16:21 -t 3.5 -b 0 'Christiane F.mkv' out.gif`
+`make-gif -o -b -s 16:21 -l 3.5 'Christiane F.mkv' out.gif`
 
 ![subtitles](examples/subtitles.gif)
 
diff --git a/make-gif b/make-gif
index 7aa845e..582a312 100755
--- a/make-gif
+++ b/make-gif
@@ -1,28 +1,32 @@
 #!/usr/bin/env zsh
 # export a clip from a video as a gif
 
-local callstr="$0"
-local hasgsic=$(whence gifsicle)
+local callstr=$0
+local hasgsic
+
+[[ $(whence gifsicle) ]] && hasgsic=true
 
 print_error() {
 	echo -e "\e[1;31merror:\e[0m $1\n"
 }
 
 usage() {
-	[[ "$1" != "" ]] && print_error $1
+	[[ -z $1 ]] || print_error $1
 	echo "Usage: $callstr [OPTIONS...] <infile> <outfile>"
+	echo "Create an animated gif from a video"
 	echo ""
-	echo "             description  option     default val"
-	echo "              start time  -s <time>  00:00:00"
-	echo "       length in seconds  -t <num>   full length"
-	echo "                 gif fps  -f <num>   10"
-	echo "         gif pixel width  -w <num>   480"
-	echo "      use subtitle track  -b <int>   none"
-	echo "       number of colours  -c <int>   256"
-	echo "     dithering algorithm  -d <str>   sierra2_4a"
-	echo "redraw only changed rect  -r"
-	[[ $hasgsic ]] && echo "  optimise with gifsicle  -o"
-	echo "         print this help  -h"
+	echo -e "                  \e[1mdescription  opt longform  arg     default val\e[0m"
+	echo "                   start time  -s  --start   <time>  00:00:00"
+	echo "            length in seconds  -l  --length  <num>   full length"
+	echo "                      gif fps  -f  --fps     <num>   10"
+	echo "           output pixel width  -w  --width   <num>   480"
+	echo "                use subtitles  -b  --sub     [int]   track 0, if enabled"
+	echo "   (optionally specify track)"
+	echo "            number of colours  -c  --colours <int>   256"
+	echo "          dithering algorithm  -d  --dither  <str>   sierra2_4a"
+	echo "redraw only changed rectangle  -r  --rect"
+	[[ $hasgsic ]] && echo "  optimise with gifsicle  -o  --optimise"
+	echo "              print this help  -h  --help"
 	exit 1
 }
 
@@ -37,7 +41,7 @@ rm_tmps() {
 }
 
 abort() {
-	[[ "$1" != "" ]] && print_error $1
+	[[ -z $1 ]] || print_error $1
 	rm_tmps
 	exit 1
 }
@@ -59,123 +63,85 @@ local timepat='^(([0-9][0-9]:){1,2}[0-9][0-9]|[0-9]+)(\.[0-9]+){0,1}$'
 local numpat='^([1-9][0-9]*(\.[0-9]+){0,1}|0\.[0-9]*[1-9])$'
 local intpat='^[1-9][0-9]*$'
 local zintpat='^[0-9]+$'
-local dithpat='^(bayer[0-5]|heckbert|floyd_steinberg|sierra2|sierra2_4a)$'
-
-# used to hold '-t' if length is used
-local t=""
-
-# used to hold subtitle options, if present
-local substr=""
-
-# really annoying, but no other good way to do optional args 
-if [[ $hasgsic ]]; then
-	while getopts :s:t:f:w:b:c:d:rho opt; do
-		case "$opt" in
-			s) 
-				[[ ! $(echo $OPTARG | grep -oE "$timepat") ]] \
+local dithpat='^(none|bayer[0-5]|heckbert|floyd_steinberg|sierra2|sierra2_4a)$'
+
+zparseopts -D -E -M -A args \
+	s:  -start:=s \
+	l:  -length:=l \
+	f:  -fps:=f \
+	w:  -width:=w \
+	b:: -sub::=b \
+	c:  -colours:=c -colors:=c \
+	d:  -dither:=d \
+	r   -rect=r \
+	o   -optimise=o -optimize=o \
+	h   -help=h
+
+local optarg
+for opt in ${(@k)args}; do
+	unset optarg
+	[[ -z $args[$opt] ]] || optarg=$args[$opt]
+	case $opt in
+			-s) 
+				[[ ! $(echo $optarg | grep -oE "$timepat") ]] \
 					&& usage "malformed start timestamp"
-				start="$OPTARG"
+				start="$optarg"
 				;;
-			t)
-				[[ ! $(echo $OPTARG | grep -oE "$numpat") ]] \
+			-l)
+				[[ ! $(echo $optarg | grep -oE "$numpat") ]] \
 					&& usage "length must be a positive rational number"
-				length=$OPTARG
-				t="-t"
+				length=(-t $optarg)
 				;;
-			f)
-				[[ ! $(echo $OPTARG | grep -oE "$numpat") ]] \
+			-f)
+				[[ ! $(echo $optarg | grep -oE "$numpat") ]] \
 					&& usage "fps must be a positive rational number"
-				fps=$OPTARG
+				fps=$optarg
 				;;
-			w)
-				[[ ! $(echo $OPTARG | grep -oE "$intpat") ]] \
+			-w)
+				[[ ! $(echo $optarg | grep -oE "$intpat") ]] \
 					&& usage "width must be a positive integer"
-				width=$OPTARG
+				width=$optarg
 				;;
-			b)
-				[[ ! $(echo $OPTARG | grep -oE "$zintpat") ]] \
+			-b)
+				[[ ! -z $optarg ]] && [[ ! $(echo $optarg | grep -oE "$zintpat") ]] \
 					&& usage "sub track index must be a non-negative integer"
-				strack=$OPTARG
+				[[ -z $optarg ]] && strack=0 || start=$optarg
 				subs=true
 				;;
-			c)
-				[[ ! $(echo $OPTARG | grep -oE "$intpat") ]] \
-					|| [[ $OPTARG -gt 256 || $OPTARG -lt 2 ]] \
+			-c)
+				[[ ! $(echo $optarg | grep -oE "$intpat") ]] \
+					|| [[ $optarg -gt 256 || $optarg -lt 2 ]] \
 					&& usage "colour count must be an integer in the range 2-256"
-				colour_count=$OPTARG
+				colour_count=$optarg
 				;;
-			d)
-				[[ ! $(echo $OPTARG | grep -oE "$dithpat") ]] \
-					&& usage "dithering algorithm must be one of bayer<0-5>, heckbert, floyd_steinberg, sierra2, sierra2_4a"
-				dithalg=$OPTARG
-				[[ $(echo $OPTARG | grep -o bayer) ]] \
-					&& dithalg="bayer:bayer_scale=$(echo $OPTARG | grep -oE '[0-5]')"
-				;;
-			o) gsic=true ;;
-			r) rectmode=":diff_mode=rectangle" ;;
-			h) usage ;;
-			[?]) usage "unrecognised option" ;;
-		esac
-	done
-else
-	while getopts :s:t:f:w:b:c:d:rh opt; do
-		case "$opt" in
-			s) 
-				[[ ! $(echo $OPTARG | grep -oE "$timepat") ]] \
-					&& usage "malformed start timestamp"
-				start="$OPTARG"
-				;;
-			t)
-				[[ ! $(echo $OPTARG | grep -oE "$numpat") ]] \
-					&& usage "length must be a positive rational number"
-				length=$OPTARG
-				t="-t"
-				;;
-			f)
-				[[ ! $(echo $OPTARG | grep -oE "$numpat") ]] \
-					&& usage "fps must be a positive rational number"
-				fps=$OPTARG
-				;;
-			w)
-				[[ ! $(echo $OPTARG | grep -oE "$intpat") ]] \
-					&& usage "width must be a positive integer"
-				width=$OPTARG
+			-d)
+				[[ ! $(echo $optarg | grep -oE "$dithpat") ]] \
+					&& usage "dithering algorithm must be one of none, bayer<0-5>, heckbert,\nfloyd_steinberg, sierra2, sierra2_4a"
+				dithalg=$optarg
+				[[ $(echo $optarg | grep -o bayer) ]] \
+					&& dithalg="bayer:bayer_scale=$(echo $optarg | grep -oE '[0-5]')"
 				;;
-			b)
-				[[ ! $(echo $OPTARG | grep -oE "$zintpat") ]] \
-					&& usage "sub track index must be a non-negative integer"
-				strack=$OPTARG
-				subs=true
-				;;
-			c)
-				[[ ! $(echo $OPTARG | grep -oE "$intpat") ]] \
-					|| [[ $OPTARG -gt 256 || $OPTARG -lt 2 ]] \
-					&& usage "colour count must be an integer in the range 2-256"
-				colour_count=$OPTARG
-				;;
-			d)
-				[[ ! $(echo $OPTARG | grep -oE "$dithpat") ]] \
-					&& usage "dithering algorithm must be one of bayer<0-5>, heckbert, floyd_steinberg, sierra2, sierra2_4a"
-				dithalg=$OPTARG
-				[[ $(echo $OPTARG | grep -o bayer) ]] \
-					&& dithalg="bayer:bayer_scale=$(echo $OPTARG | grep -oE '[0-5]')"
-				;;
-			r) rectmode=":diff_mode=rectangle" ;;
-			h) usage ;;
-			[?]) usage "unrecognised option" ;;
-		esac
+			-o) gsic=true; [[ -z $hasgsic ]] && usage "gifsicle program not found" ;;
+			-r) rectmode=":diff_mode=rectangle" ;;
+			-h) usage ;;
+	esac
+done
+
+# check some error conditions
+if [[ ${#@} -gt 2 ]]; then
+	for opt in $@; do
+		[[ $opt[1] == '-' ]] && usage "unrecognised option $opt"
 	done
+	usage "trailing file arguments detected"
 fi
-shift $OPTIND-1
 
-# check some error conditions
-[[ ${#@} -gt 2 ]] && usage "trailing arguments detected"
+[[ ${#@} -eq 1 ]] && usage "no output file specified"
 
-[[ ${#@} -lt 2 ]] && usage "no output file specified"
+[[ ${#@} -eq 0 ]] && usage "no input file specified"
 
-[[ "${2:e}" != "gif" ]] && usage "output file must have a .gif file extension"
+[[ $1 != "%d.png" ]] && [[ ! -f $1 ]] && usage "input file not found"
 
-[[ "$1" != "%d.png" ]] && [[ ! -f "$1" ]] && usage "input file not found"
+[[ ${2:e} != "gif" ]] && usage "output file must have a .gif file extension"
 
 # make links
 local tmp_pref_i
@@ -186,7 +152,7 @@ while [[ -f "${tmp_pref_i}-palette.png" ]] || [[ -f "${tmp_pref_i}-in" ]]; do
 	tmp_pref_i="${tmp_pref_i}-1"
 done
 
-tmp_pref="${tmp_pref_i}"
+tmp_pref=${tmp_pref_i}
 
 
 ln -s "${1:a}" "${tmp_pref}-in" \
@@ -195,25 +161,26 @@ ln -s "${1:a}" "${tmp_pref}-in" \
 # get output height using aspect ratio
 local height
 local as
-
 height=-1
 ffprobe -loglevel -8 -print_format json -show_streams "${tmp_pref}-in" \
 	| grep -m 1 display_aspect_ratio | grep -Eo '[0-9]+:[0-9]+' \
 	| IFS=':' read -A as
-[[ "$as" != "" ]] && let "height = ${width} * ${as[2]} / ${as[1]}"
+[[ -z $as ]] || let "height = ${width} * ${as[2]} / ${as[1]}"
 
+# convenience var
+local substr
 [[ $subs ]] && substr="subtitles=${tmp_pref}-in:si=$strack,"
 
 # convert
 echo "pass 1..."
-ffmpeg -loglevel 16 -y -ss "$start" $t $length -i "${tmp_pref}-in" -copyts -filter_complex \
+ffmpeg -loglevel 16 -y -ss "$start" ${length[@]} -i "${tmp_pref}-in" -copyts -filter_complex \
 	"${substr}setsar=1/1,fps=$fps,scale=${width}:${height}:flags=lanczos,palettegen=max_colors=${colour_count}" \
 	${tmp_pref}-palette.png
 
 [[ $? -ne 0 ]] && fferr=true
 
 [[ ! $fferr ]] && echo "pass 2..." && ffmpeg -loglevel 24 \
-	-ss $start $t $length \
+	-ss $start ${length[@]} \
 	-i "${tmp_pref}-in" -i ${tmp_pref}-palette.png -copyts -filter_complex \
 	"${substr}setsar=1/1,fps=$fps,scale=${width}:${height}:flags=lanczos[x];[x][1:v]paletteuse=dither=${dithalg}${rectmode}" \
 	"$2"
@@ -221,6 +188,7 @@ ffmpeg -loglevel 16 -y -ss "$start" $t $length -i "${tmp_pref}-in" -copyts -filt
 [[ $? -ne 0 ]] && fferr=true
 
 [[ $fferr ]] && abort
+
 rm_tmps
 
 # gifsicle