preview file with fzf and nvr

nvrp

#!/bin/bash
# simple script to preview files with the help of fzf

cwd=$(pwd)

# set up
nvr --nostart -cc 'let nvrp_buffer=""'

set_variables='mime_list=( "application/json" "text/" ); mime=$(file --mime-type {} | cut -d " " -f 2)'
f_is_text='for m in ${mime_list[@]}; do test "${mime#$m}" != "$mime" && break || false; done'

vim_expr_before='let old_nvrp_buffer=nvrp_buffer'
vim_expr='buflisted("{}") > 0 && execute(["buffer {}", "let nvrp_buffer=\"\"", "echo nvrp_buffer"])+1 || execute(["edit {}", "let nvrp_buffer=\"{}\""])'
vim_expr_after='if old_nvrp_buffer != "" | execute("bdelete " . old_nvrp_buffer) | unlet old_nvrp_buffer | endif'


cmd=$(echo "$set_variables; $f_is_text && nvr --nostart -cc '$vim_expr_before' --remote-expr '$vim_expr' -c '$vim_expr_after'" | sed "s#{}#$cwd/{}#g")

f=$(fzf --multi --reverse --bind 'ctrl-space:toggle' --no-height --preview-window up:0 --preview "$cmd" $@)

success=$?

# cleaning up or opening file(s)
if test $success -eq 0
then
    nvr --nostart -cc 'unlet nvrp_buffer' $f
    echo "opening $(echo $f | tr '\n' ' ')"
else
    nvr --nostart --remote-expr \
        'buflisted(nvrp_buffer) > 0 && execute(["bdelete " . nvrp_buffer])' \
        -c 'unlet nvrp_buffer' > /dev/null
    echo "No file to opened"
fi