cvccreate

#!/bin/bash
################################################################################
# Loading configuration
################################################################################

CVCINTERNAL_SCRIPTROOT=$(dirname "$0")
source "${CVCINTERNAL_SCRIPTROOT}/config"

# This array stores custom constant definitions
declare -A CVCINTERNAL_CUSTOMCONSTANTS

################################################################################
# Documentation
################################################################################

# Return code reference
# 1     Syntax error in invocation
# 2     Missing argument
# 3     Target audio file does not exist
# 4     Target template does not exist
# 5     CVC file already exists and force mode is off
# 16    Internal error

# Show usage
function usage {
    echo "Creates a CVC file for a given audio file. The script may use an optional"
    echo "CVC template."
    echo ""
    echo "Usage: cvccreate [-f] [-h] [-t <template>] [-v] [-C <name>=<value>] <file>"
    echo ""
    echo "Options:"
    echo "-C <name>=<value> Defines a custom constant of name <name> and value"
    echo "                  <value>. Custom constants may be used with templates"
    echo "                  supporting content substtution. This option may appear"
    echo "                  more than once."
    echo "-f                Overwrite current cvc file."
    echo "-h                Show this message."
    echo "-t <template>     The name of the CVC template to use, without the .cvt"
    echo "                  extension. CVC templates are used to prestage CVC files"
    echo "                  with static or dynamic content".
    echo "-v                Verbose mode."
    echo ""
    echo "Arguments:"
    echo "<file>        The name of an audio file."
}

################################################################################
# Option and argument parsing
################################################################################

# Calling option parser
while getopts ":fht:vC:" option; do
    case "${option}" in
        # -f: Force mode
        f)
            FORCE=1
            ;;

        # -h: Help
        h)
            usage
            exit
            ;;

        # -t: Template
        t)
            CVCTemplate="${CFG_CVCTemplatesPath}/${OPTARG}.${CFG_FileExtensions_CVCTemplates}"
            ;;

        # -v: Verbose mode
        v)
            VERBOSE=1
            ;;

        # -C: Constant definition
        C)
            # Checking constant definition
            if [[ ! "${OPTARG}" == *"="* ]]
            then
                >&2 echo "ERROR: Bad constant definition: ${OPTARG}"
                usage
                [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 1 || exit 1
            fi

            # Storing the constant
            constantName="${OPTARG%=*}"
            constantValue="${OPTARG#*=}"
            CVCINTERNAL_CUSTOMCONSTANTS["${constantName}"]="${constantValue}"
            ;;

        # Syntax error
        \?)
            >&2 echo "ERROR: Invalid option: -${OPTARG}"
            usage
            [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 1 || exit 1
            ;;

        # Syntax error
        :)
            >&2 echo "ERROR: Option -${OPTARG} requires an argument."
            usage
            [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 1 || exit 1
            ;;

        # Any other value is an internal error
        *)
            >&2 echo "ERROR: Internal getopts error."
            [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 16 || exit 16
            ;;
    esac
done

shift $((OPTIND-1))

# Checking whether an audio file was supplied as an argument.
if [ -z "$1" ]
then
    >&2 echo "ERROR: No audio file specified."
    usage
    [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 2 || exit 2
fi

################################################################################
# Additional checks
################################################################################

# Abstracting supplied arguments
targetAudioFile="$1"

# Checking whether the supplied audio file does exist
if [ ! -f "${targetAudioFile}" ]
then
    >&2 echo "ERROR: The audio file ${targetAudioFile} does not exist!"
    [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 3 || exit 3
fi

# Generating related filenames
targetFileBasename=$(basename "${targetAudioFile}" ".${CFG_FileExtensions_Audio}")
targetFileBasedir=$(dirname "${targetAudioFile}")
targetCVCFile="${targetFileBasename}.${CFG_FileExtensions_CVC}"

# Checking whether the CVC template is valid
if [ "${CVCTemplate}" ] && [ ! -f "${CVCTemplate}" ]
then
    >&2 echo "ERROR: CVC template file '${CVCTemplate}' does not exist."
    [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 4 || exit 4
fi

# We need to be sure the CVC file does not already exist, unless FORCE mode
# is defined
if [ -f "${targetCVCFile}" ] && [ -z "${FORCE}"]
then
    >&2 echo "ERROR: The CVC file '${targetCVCFile}' already exists."
    >&2 echo "Use the -f option to overwrite."
    [[ "${BASH_SOURCE[0]}" != "${0}" ]] && return 5 || exit 5
fi

################################################################################
# Creating CVC file
################################################################################

currentDate=$(date -I)

[ "${VERBOSE}" ] && echo "Creating CVC file ${targetCVCFile}..."
echo "# Cascaded Vorbis Comments file" >> "${targetCVCFile}"
echo "# Created: ${currentDate}" >> "${targetCVCFile}"

if [ "${CVCTemplate}" ]
then
    cat "${CVCTemplate}" >> "${targetCVCFile}"
fi