Download getcourse video

download-getcourse-video.sh

#!/usr/bin/env bash

set -euo pipefail

function failExit() {
	local msg="$1"

	echo "FAIL: $msg" >&2
	exit 1
}

TASKNAME="${1-}"
LINK="${2-}"



[ -n "$TASKNAME" ] || failExit "no task name"

[ -n "$LINK" ] || failExit "no link"

cd "`dirname $0`"

if [ ! -e "$TASKNAME/dl.ended" ] ; then
	mkdir -p "$TASKNAME"

	MASTER_FILE="$TASKNAME/master.txt"
	wget --continue -O "$MASTER_FILE" "$LINK"

	PLAYLIST_LINK="`grep -E "^https" "$MASTER_FILE" | tail -n 1`"

	PLAYLIST_FILE="$TASKNAME/playlist.txt"
	wget --continue -O "$PLAYLIST_FILE" "$PLAYLIST_LINK"

	cnt=1

	grep '^https' "$PLAYLIST_FILE"  | while read url ; do 
		echo $cnt
		wget -O "$TASKNAME/$cnt.mp4" --continue "$url"
		cnt=$((cnt + 1))
	done

	touch "$TASKNAME/dl.ended"
else
	echo " -- Already downloaded, skipping."
fi	

if [ ! -e "$TASKNAME/combine1.ended" ] ; then
	ANYFILE="false"
	FILES=""
	START=1
	END=1000
	CYCLE=1

	while true ; do
		echo "CYCLE: $CYCLE, start $START, end $END"

		ANYFILE="false"

		if [ ! -e "$TASKNAME/$START.mp4" ] ; then
			break
		else
			CURRENT_TARGET="$TASKNAME/combined-$CYCLE.mp4"

			if [ ! -e "$TASKNAME/combined-$CYCLE.mp4" ] ; then
				COMMAND="mkvmerge -o $TASKNAME/combined-$CYCLE-tmp.mp4 $TASKNAME/$START.mp4"
				SEQ_START=$((START + 1))
				for i in `seq $SEQ_START 1 $END` ; do
					if [ ! -e "$TASKNAME/$i.mp4" ] ; then
						break
					fi

					ANYFILE="true"
					COMMAND="$COMMAND + $TASKNAME/$i.mp4"
				done

				if [ "$ANYFILE" = "true" ] ; then
					$COMMAND
					mv "$TASKNAME/combined-$CYCLE-tmp.mp4" "$CURRENT_TARGET"
				else
					cp "$TASKNAME/$START.mp4" "$TASKNAME/combined-$CYCLE.mp4"
				fi
			else
				echo " -- Current target alredy combined, cycle $CYCLE"
			fi

			FILES="$FILES $CURRENT_TARGET"

			START=$((START + 1000))
			END=$((END + 1000))
			CYCLE=$((CYCLE + 1))
		fi
	done
	touch "$TASKNAME/combine1.ended"
	echo "FILES: $FILES"
else
	echo " -- Already combined (first combine)."
fi

if [ ! -e "$TASKNAME/combine-final.ended" ] ; then
	FILES="`ls -v $TASKNAME/combined-*.mp4`"
	set -- $FILES

	if [ "$#" = 1 ] ; then
		mv "$1" "$TASKNAME/$TASKNAME.mp4"
	elif [ "$#" = 0 ] ; then
		failExit "No precombined files found"
	else
		FIRST="$1"
		shift

		COMMAND="mkvmerge -o $TASKNAME/$TASKNAME.mp4 $FIRST"
		for i in "$@" ; do
			COMMAND="$COMMAND + $i"
		done

		$COMMAND
	fi

	touch "$TASKNAME/combine-final.ended"
else
	echo " -- Already completely combined."
fi