#!/bin/fish

function preview -a infile -d "preview media with mpv"
    if test -z $infile
        help
        exit 1
    end
    mpv --no-resume-playback --start=0 --osd-fractions --osd-level=3 $infile
end

function cut -a infile from to outfile -d "cut out portion to new media file"
    if test -z $outfile
        help
        exit 1
    end
    ffmpeg -ss $from -i $infile -t to -c copy $outfile
end

function cover -a infile outfile title gravity x y -d "create cover"
    if test -z $title
        help
        exit 1
    end
    test -z $x && set x 0
    test -z $y && set y 0
    test -z $gravity && set gravity center
    set tmpblur /tmp/tmpblur.jpg
    magick convert $infile -blur 0x8 $tmpblur
    magick convert $tmpblur \
        -gravity $gravity \
        -interline-spacing 20 \
        -pointsize 120 -font "$SC_FONT" \
        -fill '#fdf6e3' -stroke '#fdf6e3' -strokewidth 40 \
        -annotate +$x+$y "$title"\
        -fill '#839496' -stroke '#839496' -strokewidth 5 \
        -annotate +$x+$y "$title"\
        $outfile
end

function chapter -a infile outfile title duration gravity -d "prepend chapter to video"
    if test -z $title
        help
        exit 1
    end
    test -z $duration && set duration 3
    set tmpjpeg /tmp/tmpjpeg.jpg
    set tmpcover /tmp/tmpcover.jpg
    set tmpchapter /tmp/chapter.mp4
    ffmpeg -i $infile -vframes 1 -f image2 -y $tmpjpeg
    cover $tmpjpeg $tmpcover $title
    ffmpeg \
      -loop 1 -framerate 30 -i $tmpcover \
      -loop 1 -framerate 30 -i $tmpjpeg \
      -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000 \
      -filter_complex "
      [0:v]fade=t=out:st=3:d=1:alpha=1[v0];
      [1:v][v0]overlay" \
      -c:v h264 -crf 0 -preset ultrafast -pix_fmt yuv444p \
      -t 5 \
      -y $tmpchapter
    join $outfile $tmpchapter $infile
    preview $outfile
end

function join -a outfile
    set infile "/tmp/ffmpeg.concat"
    rm $infile
    for file in $argv[2..-1]
        set file (readlink -f $file)
        echo "file $file" >> $infile
    end
    ffmpeg -f concat -safe 0 -i $infile -c copy $outfile
end

function concat -a indir outfile -d "concat all media files in folder to a new media file"
    if test -z $outfile
        help
        exit 1
    end
    set -e files
    for file in (ls $indir)
        set --append files $indir/$file
    end
    join $outfile $files
end

function help
    echo "Usage: mediacut <command> [...args]"
    echo " commads:"
    echo "  preview <infile>"
    echo "  cut <infile> <from> <to>"
    echo "  chapter <infile> <title>"
    echo "  join <outfiles> <...infiles>"
    echo "  concat <indir> <outfile>"
end

if test (count $argv) -lt 2
    help
    exit 1
end

switch $argv[1]
    case preview cut join concat chapter help
        $argv
    case "*"
        help
end