export

#!/bin/bash

## export settings files from this computer to the repository
## Usage:
## ./export list of files
#    exports files "list", "of" and "files", if they exist in "~"
#    cannot handle paths to files
#    treats all filenames as if they begin with '.'

# source for files
src="$HOME"

# path to repo from ${src}
repo="config"

# dest directory for files, relative to ${repo}
dest="src"

# make sure destination can be safely written to
if ! [ -e "${dest}" ];
then # it doesn't exist
    mkdir "${dest}"
elif ! [ -d "${dest}" ];
then # it does exist, but it isnt a directory
    echo "error: destination directory exists, but is not a directory"
    echo "aborting"
    exit 1
fi

# files to be exported
if [ "$#" -le 0 ] ; # no arguments
then
    echo "no files to export, aborting"
    exit 1
else
    files="$(
        IFS=$'\n'; echo "$*"| # all the files listed in the command line args
            sed 's:^\.*:.:' # all treated as hidden files
        )"
fi

# files which would be overwritten
overwrites="$(
    echo "${files}"| # for each file
        sed 's:^\.*::'| # trim all leading '.'s. files must not be hidden
        while IFS='' read file;
        do
            ls -1a "${dest}" | grep "^${file}$" # file exists in destination directory, as a visible file
        done
            )"
if [ -n "${overwrites}" ];
then
    echo "This action will overwrite the following files:"
    echo "${overwrites}"|
        sed "s:^:${src}/${repo}/${dest}/:" # format each line nicely with the path
fi

echo -n "Are you sure? (y/N): "
read confirm
if ! [ -t 0 ] ;
then # open in a pipe
    # simulate user input
    echo "${confirm}"
fi
if echo "${confirm}"|grep -Eq "[Yy]+([Ee]+[Ss]+)*" ;
then # they tried to say yes
    echo "${files}"| # for each file
        while IFS='' read file; 
        do
            dstFile="$(echo "${file}"|sed 's:^\.*::')" # visible name for the file
            if [ -e "${src}/${file}" ];
            then # source file exists
                cp -fRTL "${src}/${file}" "${src}/${repo}/${dest}/${dstFile}" # copy the file, recursively, following all symlinks, treating destination folders as files, forcing overwrite
            else # file doesn't exist
                echo "Warning: cannot export nonexistent file \"${src}/${file}\"" # don't create bad links
            fi
        done
else # they said something else; assume no
    echo "aborting" # let the user know nothing happened
    exit 1
fi