AMPGet v1.1 - Script to download entire music archives from http://amp.dascene.net/ at once.

#!/bin/bash

# AMPGet v1.1 - Makes downloading entire music archives from http://amp.dascene.net/ more comfortable.

OIFS=$IFS
OTEXT=
URL=http://amp.dascene.net/
HTML=/media/ramdisk/detail.html
DEF_OUTPATH=/media/ramdisk/
OUTPATH=$DEF_OUTPATH

function ERROR() # display error message, infotext and exit with return code 1
{
    echo -e "\n\033[0;31m$1\nUsage: amp-get.bash -c [composer ID] -o [output path]\n\
If no output path is given the default path $DEF_OUTPATH will be used.\033[0m\n"
    exit 1
}

function STRIP() # remove html crap from plain text
{
    TEXT=$1
    while [ ! "$OTEXT" = "$TEXT" ]; do
        OTEXT=$TEXT
        TEXT=${TEXT#*<*>}
        TEXT=${TEXT%</*>*}
    done
}

function GET_NAME() # obtain handle and real name
{
    STRING=$(grep -nm 1 $1 $HTML)
    typeset -i LINE=${STRING%':    '*}+1
    GET_META $LINE
}

function GET_META() # obtain additional info which regards to a certain entry, but is placed on a different line
{
    RAW_NAME=$(sed -n $1"p" $HTML)
    STRIP $RAW_NAME
}

while getopts :c:C:o:O: OPT; do
    case $OPT in
        c|C)
            if [[ ! $OPTARG =~ ^[0-9]+$ ]]; then ERROR "Composer ID must be a number!"; fi
            ID=$OPTARG
            ;;
        o|O)
            if [ ! -d $OPTARG ]; then ERROR "Output path doesn't exist."; fi
            OUTPATH=$OPTARG
            ;;
        \?)
            ERROR "Unknown option: "$OPTARG
            ;;
    esac
done
if [ -z $ID ]; then ERROR "Composer ID must be given!"; fi

if wget -q $URL'detail.php?detail=modules&view='$ID -O $HTML; then
    IFS=$'\n'
    typeset -i COUNT=0
    typeset -i OK=0
    typeset -i FAIL=0
    cd $OUTPATH
    echo -e "\nOutput path is: "$OUTPATH"\nComposer ID is: "$ID
    GET_NAME 'class="descript">Handle:'
    HANDLE=$TEXT
    echo "Handle is:      "$HANDLE
    GET_NAME '<td class="descript">Real&nbsp;Name: </td>'
    REAL_NAME=$TEXT
    echo -e "Real name is:   "$REAL_NAME"\n"
    for MOD_ENTRY in $(grep -n '" target="_new">' $HTML); do
        COUNT=$COUNT+1
        typeset -i POS=0
        typeset -i LINE=${MOD_ENTRY%':    '*}+4
        STRIP $MOD_ENTRY
        RAW=$TEXT
        TYPE=
        GET_META $LINE
        if [ ! $TEXT = MOD ]; then TYPE="."$TEXT; fi
        while [ ${#RAW} -gt $POS ]; do
            if [ "${RAW:$POS:3}" = '&nb' ]; then
                POS=$POS+5
# The following chars are not allowed for file names in either the Linux or the AmigaDOS file system and will be replaced by an underscore "_"
            elif [ "${RAW:$POS:1}" = \* ] || [ "${RAW:$POS:1}" = \? ] || [ "${RAW:$POS:1}" = \| ] || [ "${RAW:$POS:1}" = \@ ] || [ "${RAW:$POS:1}" = \" ]
            then
                NAME=$NAME"_"
            elif [ "${RAW:$POS:4}" = '&lt;' ] || [ "${RAW:$POS:4}" = '&gt;' ]; then
                NAME=$NAME"_"
                POS=$POS+3
            else
                NAME=$NAME${RAW:$POS:1}
            fi
            POS=$POS+1
        done
        while [ -f $NAME$TYPE".mod.gz" ]; do NAME=$NAME"_"; done
        NAME=$NAME$TYPE".mod.gz"
        echo -n "Downloading "$NAME"...        "
        MOD_ID=${MOD_ENTRY#*'<td><a href="'}
        MOD_ID=${MOD_ID%'" target="_new">'*}
        FILE=$URL$MOD_ID
        if wget -q $FILE -O $NAME; then
            echo -e "\033[0;32mOK\033[0m"
            OK=$OK+1
        else
            echo -e "\033[0;31mFAILED!\033[0m"
            FAIL=$FAIL+1
        fi
        NAME=""
    done
    IFS=$OIFS
    if [ $COUNT -gt 0 ]; then
        echo -e "\nNumber of files: "$COUNT"    Downloaded: "$OK"    Failed: "$FAIL"\n"
        echo -e "Composer ID was: "$ID"\nHandle was:      "$HANDLE"\nReal name was:   "$REAL_NAME"\n"
    else
        echo -e "Nothing to download.\n"
    fi
    rm -f $HTML
else
    ERROR "Unable to retrieve composer information. Possibly due to difficulties with internet connection or page is offline."
fi