#!/bin/sh

# find a string in the current directory and below
# while automatically ignoring repository metadata.

# Licence: LGPLv2
# Author:
#    http://www.pixelbeat.org/
# Notes:
#    One can either supply a regular expression or fixed string.
#    If just a fixed string is supplied then we specify the -F option to
#    grep so that it uses fast string matching (why doesn't it do this itself?),
#    otherwise we default to an extended regular expression.
#    The match type auto selection is disabled if a specific grep
#    match type is specified as part of the optional grep options.
# Changes:
#    V0.1, 25 Apr 2005, Initial release
#    V0.2, 25 Mar 2008, Add grep colours if available
#                       Add more repo dirs to ignore
#                       Support regular expressions not just fixed strings
#                       Support passing extra user specified options to grep
#    V0.3, 26 Mar 2008, Fix bug generating $repo_ign dirs
#    V0.4, 30 Sep 2008, Tweak grep colour to be usable on light terminals
#    V0.7, 29 Jan 2015
#      http://github.com/pixelb/scripts/commits/master/scripts/findrepo

proc usage {
shell {
echo "Usage:    $[basename $0] ['grep options'] search_expr [file wildcard]
examples: $[basename $0] 'main' '*.[ch]'          #fixed string search
          $[basename $0] '(main|mane)' '*.[ch]'   #regular expression search
          $[basename $0] '-F' 'main(' '*.[ch]'    #force fixed string search
          $[basename $0] '-L -F' 'main(' '*.[ch]' #extra grep options"
} >&2
    exit 1
}

if test $Argc -eq 0 || test $Argc -gt 3 {
    usage
}

#enable search highlighting if supported by grep
echo | grep --color=auto "" >/dev/null !2 > !1 && setglobal colour = '"--color=auto'"

if test $Argc -eq 1 {
    setglobal glob = ''*''   # common shortcut to avoid needing to specify all files
} elif test $Argc -eq 2 {
    # if $1 begins with a '-' then we might be hitting the
    # ambiguous case where grep options are being specified,
    # so warn with info about (avoiding) the ambiguity
    if ! test $(1##-*) {
      echo "\
Warning: treating '$1' as the grep pattern, not extra options.
If this is intended, avoid the warning with an empty first parameter.
If this is not intended, please specify the file wildcard." > !2
    }
    setglobal glob = $2
} elif test $Argc -eq 3 {
    setglobal grep_options = $1
    shift
    setglobal glob = $2
}

#default to -E or -F as appropriate, not -G
if ! printf "%s\n" $grep_options |
     grep -E -- "-([EFGP]|regexp|fixed)" >/dev/null !2 > !1 {
    #used fixed string matching for speed unless an ERE metacharacter used
    echo $1 | grep '[.[\()*+?{|^$]' >/dev/null && setglobal type = '"-E'" || setglobal type = '"-F'"
    setglobal grep_options = ""$grep_options $type""
}

setglobal repodirs = '".git .svn CVS .hg .bzr _darcs'"
for dir in [$repodirs] {
    setglobal repo_ign = ""$repo_ign$(repo_ign+" -o ")-name $dir""
}

find . '(' -type d -a '(' $repo_ign ')'  ')' -prune -o \
       '(' -type f -name $glob -print0 ')' |
#LANG=C is to work around grep multibyte inefficiencies
#GREP_COLOR="1;37;47" is bright yellow on black bg
env GREP_COLOR="1;33;40" LANG=C xargs -0 grep $colour $grep_options -- $1