#!/bin/sh

if [ $# -lt 2 ]
then
  echo "$0 <rate> <file>"
  exit 1
fi

RATE="$1"
FILE="$2"

OUTPUTFILE="$(echo "$2" | sed 's/\.osu//g' | cut -d']' -f1) x$RATE].osu"

AUDIO=$(grep "AudioFilename:" "$FILE" | cut -d' ' -f2- | tr -d '\n\r')
AUDIORATED=$(echo $AUDIO | cut -d'.' -f1)-x$RATE".mp3"

echo "" > "$OUTPUTFILE"

output_line () {
  printf "%s\r\n" "$1" >> $OUTPUTFILE
}

audioRate () {
  ffmpeg -i "$AUDIO" -filter:a "asetrate=$(ffprobe -v error -show_entries stream=sample_rate -of default=noprint_wrappers=1:nokey=1 "$AUDIO")*$RATE" -y "$AUDIORATED"
}

LINES=$(wc -l "$FILE" | cut -d' ' -f1)
FFILE=$(cat "$FILE")

step_skip ()
{
  printf "$(echo "$FFILE" | grep -B $LINES "$1" | head -n -1)" >> $OUTPUTFILE
  FFILE=$(echo "$FFILE" | grep -A $LINES "$1" | tail -n +2)
}

step_skip "AudioFilename:"
output_line "AudioFilename: $AUDIORATED"

PREVIEW=$(echo "$FFILE" | grep "PreviewTime:" | cut -d' ' -f2 | tr -d '\r\n')
step_skip "PreviewTime:"
output_line "PreviewTime: $(echo "$PREVIEW / $RATE" | bc | cut -d '.' -f1)"
VERSION=$(echo "$FFILE" | grep "Version:" | cut -d':' -f2- | tr -d '\n\r')
step_skip "Version:"
output_line "Version:$VERSION x$RATE"

step_skip "BeatmapID:"
output_line "BeatmapID:0"

step_skip "\[TimingPoints\]"
TIMINGPOINTS=$(echo "$FFILE" | grep -B $LINES "\[HitObjects\]" | head -n -1)
OBJECTS=$(echo "$FFILE" | grep -A $LINES "\[HitObjects\]" | tail -n +2)

output_line "[TimingPoints]"

N=$(echo "$TIMINGPOINTS" | wc -l)
I=0

echo "$TIMINGPOINTS" | awk -F ',' "{ RATE=$RATE"'
  if ($7 == 0 || $7 == 1)
  {
    if ($7 == 1)
      {print int($1/RATE)","$2/RATE","$3","$4","$5","$6","$7","$8}
    else
      {print int($1/RATE)","$2","$3","$4","$5","$6","$7","$8}
  }
}' >> "$OUTPUTFILE"

output_line "[HitObjects]"
N=$(echo "$OBJECTS" | wc -l)
echo "$OBJECTS" | awk -F "[,:]" "{RATE=$RATE"'
  if ($1)
    {print $1","$2","int($3/RATE)","$4","$5","int($6/RATE)":"$7":"$8":"$9":"$10}
}
' >> "$OUTPUTFILE"

audioRate