#!/bin/bash

if [ ! "x$0" = "x${0#-}" ]
then
    echo "Don't source me, just run!" 1>&2
    return
fi
. ${0%/*}/libdans.sh

# Load global defaults (vars: vo, archive, LFC_*, SRM_*)
loadDefaults $0


DEBUG=0
QUIET=0
KEEPGOING=0
START_INDEX=1
END_INDEX=0
USAGE="\
$0 - verify the contents of one or multiple tar.gz files
Usage: ./check-file [-d|--debug] [-k|--keepgoing] [file|lfn|surl] [[file2|lfn2|surl2] ...]
Where:
  --keepgoing    tells $0 to keep going after an error
  file           specifies the full path to a local file  OR
  lfn            specifies a Logical File Name on the LFC OR
  surl           specifies a Storage URL (srm:// or gsiftp://)
"

# Parse commandline parameters
while [ $# -gt 0 ]
do
    case "$1" in
        (-h|--help)       echo "${USAGE}"
                          exit 0
                          ;;
        (-d|--debug)      let DEBUG+=1
                          ;;
        (-k|--keepgoing)  KEEPGOING=1
                          ;;
        (-*)              echo "Invalid option: $1"
                          exit 1
                          ;;
        (*)               break
                          ;;
    esac
    shift
done

if [ $# -lt 1 ]
then
    abort 1 "${USAGE}"
fi

WORKSPACE=workspace.$$
TIMESTAMP=check-file.timestamp.$$
# set a timestamp to only use newly downloaded files
touch  ${TIMESTAMP}

# Loop over all files|lfns|surls
for file 
do
    do_get=0
    skip_md5=0
    symlink=""

    if [ "${file}" != "${file#lfn:/}" ]
    then
        do_get=1

        # Verify that we have a valid proxy before continuing
        checkProxy "${vo}"

        lfcEntry=`lfc-ls -l "${file#lfn:}" 2> /dev/null`
        if [ $? -ne 0 ]
        then
            abort 2 "Error listing file ${file}"
        fi
        if [ -z "${lfcEntry}" ]
        then
            warn "LFC file ${file} not found"
            continue
        fi

        # check if the LFC entry is a symlink
        if [ `echo "${lfcEntry}" | cut -c1,1` = "l" ]
        then
            symlink="${file}"
            file=`echo "${lfcEntry}" | sed 's/.*-> //'`
            md5file="${file##*/}"
            md5file="${md5file%.gz}.md5sum"

            # add the protocol again
            file="lfn:${file}"
            debug "Symbolic link detected: ${symlink} -> ${file}"

            debug "md5file should be ${md5file}"
            # we now know that the current entry is a symlink, usually to a tarball
            # check if we already calculated the checksums for this tarball since
            # the start of the script. If so, use it, if not, download the tarball
            if [ -r "${md5file}" -a "${md5file}" -nt "${TIMESTAMP}" ]
            then
                debug "${file} was already checked since the start of the script."
                
                do_get=0
                skip_md5=1
            else
                debug "Downloading ${file} instead"
            fi
        fi
        
    fi
    if [ "${file}" != "${file#srm:/}" ]
    then
        do_get=1
    fi
    if [ "${file}" != "${file#gsiftp:/}" ]
    then
        do_get=1
    fi

    if [ ${do_get} -ne 0 ]
    then
        # Verify that we have a valid proxy before continuing
        checkProxy "${vo}"

        info "Retrieving file ${file}"
        lcg-cp ${SRM_TIMEOUTS} "${file}" file://$PWD/"${file##*/}"
        if [ $? -ne 0 ]
        then
            warn "First attempt failed, sleeping 30 seconds and retrying..."
            sleep 30
            lcg-cp ${SRM_TIMEOUTS} "${file}" file://$PWD/"${file##*/}"
        fi
        if [ $? -ne 0 ]
        then
            warn "Second attempt failed, sleeping 90 seconds and retrying..."
            sleep 90
            date +"%Y/%m/%d-%H:%M:%S start lcg-cp -v -v ${SRM_TIMEOUTS}" 1>&2
            lcg-cp -v -v ${SRM_TIMEOUTS} "${file}" file://$PWD/"${file##*/}"
        fi
        if [ $? -ne 0 ]
        then
            abort 3 "Error retrieving ${file}"
        fi

        file="${file##*/}"
    fi

    if [ ${skip_md5} -eq 0 ]
    then
        # the file should be a .tar.gz file, extract the original archive name from it
        base=`file "${file}" | sed -n 's/.*compressed data, was \"\(.*\)\",.*/\1/p'`
        archive="${base%%-[0-9]*}"
        
        debug "file=${file} base=${base} archive=${archive}"
     
        CHECKSUM_DIR="${HOME}/dans/${archive}/checksums"
    
        # fix numbering issue in RACM tar balls
        if [ "x${archive}" = "xRACM" ]
        then
            index=${base#${archive}-}
            index=${index%.tar}
            if [ ${#index} -lt 4 ]
            then
                base="${archive}-0${index}.tar"
            fi
        fi

        # extract the tarball in a separate directory, for easy cleanup later 
        mkdir -p ${WORKSPACE}
        info "Extracting file ${file} (real name: ${base}.gz) ..."
        tar -C ${WORKSPACE} -xzf "${file}"
    
        md5file="${base}.md5sum"
        if [ -r "${md5file}" ]
        then
            warn "\"${md5file}\" exists, appending \".$$\""
            md5file="${md5file}.$$"
        fi
    
        info "Calculating checksums for all files in archive (output=${md5file})"
        echo "# ${base} START" > "${md5file}"
        (cd ${WORKSPACE}; md5deep -l -r ${archive}) | sort -k 2 >> "${md5file}"
        echo "# ${base} END" >> "${md5file}"
    
        if [ -r "${CHECKSUM_DIR}/${md5file%.$$}" ]
        then
            debug "Comparing ${md5file} to ${CHECKSUM_DIR}/${md5file%.$$}"
    
            diff "${CHECKSUM_DIR}/${md5file%.$$}" "${md5file}" && info "OK" || warn "Mismatch"
        else
            debug "${CHECKSUM_DIR}/${md5file%.$$} not found, skipping"
        fi
    else
        debug "Skipping md5deep step, reusing previous results" 
    fi

    if [ -n "${symlink}" ]
    then
        entry="${symlink##*/}"
    else
        entry="${file##*/}"
    fi
  
    if [ "${entry}" != "${base}.gz" ]
    then
        grep "${entry}" "${md5file}"
    fi

    # delete the tar ball (if downloaded!) 
    if [ ${do_get} -ne 0 ]
    then
        rm -f "${file}"
    fi
    # clear out the ${WORKSPACE}
    rm -rf ${WORKSPACE}
done

# remove the timestamp
rm -f ${TIMESTAMP}