#!/bin/bash
set -e

# Detect installed applications
if [ -f /usr/bin/eyeD3 ]; then
    eyed3=true
else
    eyed3=false
    echo "INFO: eyed3 is not installed, no metadata will be injected into music files."
fi
if [ -f /usr/bin/exiftool ]; then
    exiftool=true
else
    exiftool=false
    echo "INFO: exiftool is not installed, no metadata will be injected into pictures."
fi

# Helper functions
help() {
    echo "Usage: $0 SECTION/USER [ARGUMENTS]
Downloads the entire gallery/scraps/favorites of any furaffinity user.

Arguments:
 -h --help       This text
 -i --http       Use an insecure connection
 -o --out        The directory to put files in
 -c --cookiefile If you need to download restricted content
                 you can provide a path to a cookie file
 -p --nometa     Plain file without any additional metadata

Examples:
 $0 gallery/mylafox
 $0 -o=myla gallery/mylafox
 $0 --out=koul favorites/koul 

You can also log in to FurAffinity to download restricted content, like this:
 $0 gallery/gonnaneedabiggerboat -c=/path/to/your/cookies.txt

DISCLAIMER: It is your own responsibility to check whether batch downloading is allowed by FurAffinity terms of service and to abide by them."
    exit 1
}
cleanup() {
    rm -r "$tempfile"
}

# Arguments
if [ $# -eq 0 ]; then
    help
fi

prefix="https:"
outdir="."
metadata=true;
case "$1" in
    # Help
    -h|--help) help;;
    
    # HTTP / HTTPS
    -i|--http) prefix="http:";;

    # Output directory
    -o=*|--out=*) outdir="${1#*=}"; shift 1;;
    
    # Cookie file
    -c=*|--cookiefile=*) cookiefile="${1#*=}"; shift 1;;
    
    # Metadata
    -p|--nometa) meta=false;;
esac
mkdir -p "$outdir"

runtime_dir="$HOME"'/.cache/furaffinity-dl-ng'
mkdir -p "$runtime_dir"
tempfile="$(umask u=rwx,g=,o= && mktemp $runtime_dir/fa-dl.XXXXXXXXXX)"

trap cleanup EXIT

if [ "$cookiefile" = "" ]; then
    # Set wget with a custom user agent
    fwget() {
        wget -nv --user-agent="Mozilla/5.0 furaffinity-dl-ng (https://github.com/Xerbo/furaffinity-dl-ng)" $*
    }
else
    # Set wget with a custom user agent and cookies
    fwget() {
        wget -nv --user-agent="Mozilla/5.0 furaffinity-dl-ng (https://github.com/Xerbo/furaffinity-dl-ng)" --load-cookies "$cookiefile" $*
    }
fi

url="https://www.furaffinity.net/${@: -1}"

# Iterate over the gallery pages with thumbnails and links to artwork view pages
while true; do
    fwget "$url" -O "$tempfile"
    if [ "$cookiefile" != "" ] && grep -q 'furaffinity.net/login/' "$tempfile"; then
        echo "ERROR: You have provided a cookies file, but it does not contain valid cookies.

If this file used to work, this means that the cookies have expired;
you will have to log in to FurAffinity from your web browser and export the cookies again.

If this is the first time you're trying to use cookies, make sure you have exported them
in Netscape format (this is normally done through \"cookie export\" browser extensions)
and supplied the correct path to the cookies.txt file to this script.

If that doesn't resolve the issue, please report the problem at
https://github.com/Xerbo/furaffinity-dl-ng/issues" >&2
        exit 1
    fi

    # Get URL for next page out of "Next" button. Required for favorites, pages of which are not numbered
    next_page_url="$(grep '<a class="button-link right" href="' "$tempfile" | grep '">Next &nbsp;&#x276f;&#x276f;</a>' | cut -d '"' -f 4 | sort -u)"

    # Extract links to pages with individual artworks and iterate over them
    artwork_pages=$(grep '<a href="/view/' "$tempfile" | grep -E --only-matching '/view/[[:digit:]]+/' | uniq)
    for page in $artwork_pages; do
        # Download the submission page
        fwget -O "$tempfile" 'https://www.furaffinity.net'"$page"

        if grep -q "System Message" "$tempfile"; then
            echo "WARNING: $page seems to be inaccessible, skipping."
            continue
        fi
    
        # Get the full size image URL.
        # This will be a facdn.net link, we will default to HTTPS
        # but this can be disabled with -i or --http for specific reasons
        image_url=$prefix$(grep --only-matching --max-count=1 ' href="//d.facdn.net/art/.\+">Download' "$tempfile" | cut -d '"' -f 2)
        
        # Get metadata
        description=$(grep 'og:description" content="' "$tempfile" | cut -d '"' -f4)
        title=$(grep 'og:title" content="' "$tempfile" | cut -d '"' -f4)
        file_type=${image_url##*.}
        file="$outdir/$title.$file_type"
        
        wget "$image_url" -O "$file"
        
        # Add metadata
        if [ $file_type == "mp3" ] || [ $file_type == "wav" ] || [ $file_type == "wmv" ] || [ $file_type == "ogg" ] || [ $file_type == "flac" ]; then
            # Use eyeD3 for injecting injecting metadata into audio files (if it's installed)
            if [ $eyed3 ] && [ $metadata ]; then
                if [ -z "$description" ]; then
                    eyeD3 -t "$title" "$file"
                else
                    # HACK eyeD3 throws an error if a description containing a ":"
                    eyeD3 -t "$title" --add-comment "${description//:/\\:}" "$file"
                fi
            fi
        elif [ $file_type == "png" ] || [ $file_type == "jpg" ] || [ $file_type == "jpeg" ]; then
            # Use exiftool for injecting metadata into pictures (if it's installed)
            if [ $exiftool ] && [ $metadata ]; then
                exiftool "$file" -description="$description" -title="$title"
            fi
        fi
    done

    [ "$next_page_url" = "" ] && break
    url='https://www.furaffinity.net'"$next_page_url"
done