vgc

#!/bin/bash

# vgc -- rg with context on STDIN on $PWD, with help
# usage: pipe | vgc pattern
#    OR just:   vgc pattern [optional list of paths to search]
# optional N (single digit) *before* the pattern; default 5

# set -x
export PS4=':.$LINENO:'

# ----------------------------------------------------------------------
# preview (invoked by fzf)

# For the life of me I could not figure out how to roll this functionality
# directly into the `--preview=` option!  Oh well, this works fine too.
[[ $1 == --preview ]] && {
    shift
    q="$*"
    q=${q// /\\|}
    grep --color=always -i -e '$' -e "$q" -e 20..-..-.. -e XXX -e TODO -e NOTE -e WARNING -e OBSOLETE -e ERROR
    # I'm sure this code won't survive past 2099.  I know *I* won't :-)
    exit 0
}

# ----------------------------------------------------------------------
# main

c=5
[[ $1 =~ ^[1-9]$ ]] && c=$1 && shift
q="$1"; shift

_vgc () {
    : "c is for context"
    : "change the query and hit enter to restart with the new query string"
    : "starts with a context of 5; type a number and hit enter to change it (query string will revert to $1)"
    rg -n -C$c "$q" "$@" |
        perl -pe 's/^--\n/\0/' |
        fzf \
            -q "$q" \
            --read0 \
            --preview-window=wrap:top:75% \
            --preview="echo {} | $0 --preview {q}" \
            --print-query \
            --expect "enter,esc,ctrl-c,ctrl-n" \
            --header "ctrl-n to accept new query and restart
escape or ctrl-c to exit without doing anything
enter to open vim quickfix list with selected entries"
}

[[ -t 0 ]] || {
    VGCTMPF=$HOME/tmp/vgc.$$
    rm -f $VGCTMPF
    cat > $VGCTMPF
    trap "rm -f $VGCTMPF" 0
}

while :; do
    if [[ -t 0 ]]; then
        r=$(_vgc "$@")      # search PWD if nothing specified
    else
        r=$(cat $VGCTMPF | _vgc)
    fi

    newq=$(echo "$r" | head -1)
    [[ $newq =~ ^[1-9][0-9]*$ ]] && c=$newq || q="$newq"

    k=$(echo "$r" | sed -ne '2p')
    [[ $k == esc ]]    && exit          # user hit esc, exit
    [[ $k == ctrl-c ]] && exit          # user hit esc, exit
    [[ $k == ctrl-n ]] && continue      # user hit ctrl-n, loop
    [[ $k == enter  ]] && {             # user hit enter, open vim quickfix list
        # make a vim search pattern out of the first line of $x (which is the "query",
        # due to using "--print-query" in the fzf command)
        q=$(echo "$r" | head -1 | tr ' ' '|')

        if [[ -t 0 ]]; then
            # start vim with the quickfix list set to "$r".  \v is "very
            # magic"; allows '|' to act as alternation in regex
            vim -q <(echo "$r"|tail -n +2|grep -E ":[0-9]+:") -c copen -c "let @/='\v$q'"
        else
            # stdin was a pipe
            echo "$r"|tail -n +3
            break
        fi
    }
done