#!/bin/sh

# Copyright 2023, 2024 Paul Hänsch
# 
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
# 
# THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
# SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
# IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

I="$_DATA/index"

. "$_EXEC/cgilite/cgilite.sh"
. "$_EXEC/cgilite/storage.sh"
. "$_EXEC/cgilite/db23.sh"
. "$_EXEC/tools.sh"
. "$_EXEC/acl.sh"

_(){ printf %s\\n "$*"; }
[ "${LANGUAGE}" -a -r "${_EXEC}/l10n/${LANGUAGE}.sh" ] && . "${_EXEC}/l10n/${LANGUAGE}.sh"

show_form=true show_hits='' action='' query='' show_query='' hlevel='3' alt=''

set -- "$@" --
while [ $# -gt 0 ]; do case $1 in
  --no-form|--noform)
    show_form=''; shift 1;;
  --hits|--results)
    [ ! "$show_query" ] && show_query=true
    show_hits='true'; shift 1;;
  --query|--show-query)
    show_query=true; shift 1;;
  --no-query)
    show_query=false; shift 1;;
  --action)
    action="$(HTML "$2")"; shift 2;;
  --action=*|action=*)
    action="$(HTML "${1#*=}")"; shift 1;;
  --h1|--h2|--h3|--h4|--h5|--h6)
    hlevel="${1#--h}"; shift 1;;
  --alt)
    alt="$2"; shift 2;;
  --) shift 1; break;;
  *) set -- "$@" "$1"; shift 1;;
esac; done

[ $# -gt 0 ] && query="$*" || query="$(GET q)"
[ ! "$show_query" ] && show_query=false

searchteaser() {
  local file="$1" words db3_data
  local w l nc nl hits mhits cont mcont
  shift 1; words="$*"

  for w in ${words}; do
    grep -hiwnF "$w" "$file"
  done \
  | sort -t: -k1 -n \
  | { nc=-1 hits=0 mhits=0
    while read -r l; do
      nl="$nc" nc="${l%%:*}"
      if [ $nc -eq $nl ]; then
        hits=$((hits + 1))
      elif [ $nc -eq $((nl + 1 )) ]; then
        hits=$((hits + 1))
        cont="${cont}${BR}${l#*:}"
      elif [ $hits -gt $mhits ]; then
        mhits="$hits" mcont="$cont"
        hits=1 cont="${l#*:}"
      else
        hits=1 cont="${l#*:}"
      fi
    done

    [ $hits -gt $mhits ] \
    && STRING "$cont" \
    || STRING "$mcont"
  }
}

if [ ! "$action" -a "$LANGUAGE" != "$LANGUAGE_DEFAULT" ]; then
  action="./:${LANGUAGE}/[search]"
elif [ ! "$action" ]; then
  action="./[search]"
fi

if [ "${show_form}" = true ]; then
  cat <<-EOF
	<form class="macro search" method="GET" action="${action}">
	  <input type="search" placeholder="$(_ Search)" name="q"
	         value="$([ "$show_query" = true ] && printf %s\\n "$query" |HTML)"
	  ><button type="submit" class="search">$(_ Search)</button>
	</form>
	EOF
fi

if [ "${show_hits}" = true ]; then
  { read tags; read ntags; read words; } <<-EOF
	$(printf %s\\n "${query}" | awk '
	BEGIN { # Field separator FS should include punctuation, including Unicode Block U+2000 - U+206F
	        if ( length("¡") == 1 )  # Utf-8 aware AWK
	        FS = "([] \\t\\n\\r\"'\''()*+,./:;<=>?\\\\^`{|}~[-]|%[0-9A-Fa-f]{2}|'"$(printf '[\342\200\200-\342\201\257]')"')+";
	        else                     # UTF-8 Hack
	        FS = "([] \\t\\n\\r\"'\''()*+,./:;<=>?\\\\^`{|}~[-]|%[0-9A-Fa-f]{2}|'"$(printf '\342\200[\200-\277]|\342\201[\201-\257]')"')+";
	        fi
	      }
	{ t=0; for (n = 1; n <= NF; n++) if ($n  ~ /#[[:alnum:]_]+/)  tags[t++] = toupper($n);
	  t=0; for (n = 1; n <= NF; n++) if ($n  ~ /![[:alnum:]_]+/) ntags[t++] = toupper($n);
	  t=0; for (n = 1; n <= NF; n++) if ($n !~ /![[:alnum:]_]+/) words[t++] = tolower($n);
	  for (t in  tags) { sub(/^#/, "",  tags[t]); printf "%s	",  tags[t]; } print "";
	  for (t in ntags) { sub(/^!/, "", ntags[t]); printf "%s	", ntags[t]; } print "";
	  for (t in words) { gsub(/[!#_ ]+/, "	", words[t]); printf "%s	", words[t]; } print "";
	}
	')
	EOF

  for w in ${words}; do
    [ ! -f "$I/$w" ] && continue
  
    while read date doc freq num total; do
      P="$_DATA/pages$(UNSTRING "$doc")"
      d="$(stat -c %Y -- "$P/#index.flag" 2>&-)"
      [ "$d" -le "$date" -a -f "$P/#page.md" ] 2>&- || continue
  
      printf '%s	%f\n' "$doc" "$freq"
    done <"$I/$w"
  done \
  | awk '
        { cnt[$1]++; weight[$1] = weight[$1] ? weight[$1] + $2 : $2; }
    END { m = 0; for (d in cnt) m = ( m < cnt[d] ) ? cnt[d] : m;
          for (d in cnt) if ( cnt[d] == m ) printf "%f	%s\n", weight[d], d;
        }
  ' \
  | sort -nr \
  | while read freq doc; do
    page="$(UNSTRING "$doc")"
    [ "${page%*/\[*\]/*}" != "$page" ] && continue
    if [ "$LANGUAGE_DEFAULT" ]; then
      [ -d "${_DATA}/pages/${page}/:${LANGUAGE}/" ] && continue
      [ "${page%/:*/}" = "${page%/:${LANGUAGE}/}" ] || continue
    fi
    acl_read "$page" || continue
    has_tags "$page" $tags || continue
    has_tag "$page" $ntags && continue
    printf '%s	%s\n' "$doc" "$(searchteaser "$(mdfile "$page")" $words)"
  done \
  | { while read -r p t; do
      [ ! "$path" ] && printf '<ul class="macro search hits">'
      path="$(UNSTRING "$p")" title="$(page_title "$path")"
      path="$(HTML "$path")"
      printf '<li><h%i><a href="%s">%s</a></h%i><p class="path">%s</p><p class="teaser">%s</p></li>' \
             "${hlevel}" "$path" "$(HTML "$title")" "${hlevel}" \
             "$path" "$(UNSTRING "$t" |HTML)"
      done
    [ "$path" ] && printf '</ul>'
    [ ! "$path" -a "$alt" -a "$query" ] \
    && printf '<p class="macro search hits">%s</p>' "$(HTML "$alt")"
  }
fi