#!/bin/bash -p
###############################################################################
# BRLTTY - A background process providing access to the console screen (when in
#          text mode) for a blind person using a refreshable braille display.
#
# Copyright (C) 1995-2023 by The BRLTTY Developers.
#
# BRLTTY comes with ABSOLUTELY NO WARRANTY.
#
# This is free software, placed under the terms of the
# GNU Lesser General Public License, as published by the Free Software
# Foundation; either version 2.1 of the License, or (at your option) any
# later version. Please see the file LICENSE-LGPL for details.
#
# Web Page: http://brltty.app/
#
# This software is maintained by Dave Mielke <dave@mielke.cc>.
###############################################################################

defaultOutputRoot="doc-ktb"

. "`dirname "${0}"`/brltty-prologue.sh"
addProgramOption s string.directory sourceRoot "top-level directory of source tree" "the location of this script"
addProgramOption b string.directory buildRoot "top-level directory of build tree" "the source tree"
addProgramOption o string.directory outputRoot "top-level directory of output tree" "${defaultOutputRoot}"
addProgramOption k flag keepFiles "don't remove intermediate files"
parseProgramArguments "${@}"

set -e
umask 022
shopt -s nullglob

[ -n "${sourceRoot}" ] || sourceRoot="$(dirname "${0}")"
verifyInputDirectory "${sourceRoot}"
sourceRoot="$(cd "${sourceRoot}" && pwd)"

[ -n "${buildRoot}" ] || buildRoot="${sourceRoot}"
buildRoot="$(cd "${buildRoot}" && pwd)"

[ -n "${outputRoot}" ] || outputRoot="${defaultOutputRoot}"
verifyOutputDirectory "${outputRoot}"

unset HOME
export XDG_CONFIG_HOME=/
export XDG_CONFIG_DIRS=/

readonly newLine=$'\n'

lineGroups=()
newLineGroup() {
   local variable="${1}"

   local group="lineGroup${#lineGroups[*]}"
   lineGroups+=("${group}")
   setVariable "${variable}" "${group}"

   declare -g -a "${group}"
   eval "${group}=()"
}

addLineToGroup() {
   local group="${1}"
   local line="${2}"

   eval "${group}+="'("${line}")'
}

newDocLines() {
   newLineGroup docLines
}

beginTocEntries() {
   local variable="${1}"

   newLineGroup "${variable}"
   newDocLines

   addLineToGroup "${!variable}" "<ul>"
}

endTocEntries() {
   local group="${1}"

   addLineToGroup "${group}" "</ul>"
}

addTocEntry() {
   local group="${1}"
   local title="${2}"
   local anchor="${3}"

   addLineToGroup "${group}" "<li><a href=\"#${anchor}\">${title}</a></li>"
}

addDocLine() {
   local line="${1}"

   addLineToGroup "${docLines}" "${line}"
}

addSectionTerminator() {
   addDocLine "<hr />"
}

addAnchor() {
   local anchor="${1}"

   addDocLine "<a name=\"${anchor}\"></a>"
}

beginDocument() {
   local title="${1}"

   newDocLines
   headerLevel=0

   addDocLine "<?xml version=\"1.0\" encoding=\"utf-8\" ?>"
   addDocLine "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">"

   addDocLine "<html xmlns=\"http://www.w3.org/1999/xhtml\" lang=\"en\" xml:lang=\"en\">"
   addDocLine "<head>"
   addDocLine "<title>${title}</title>"
   addDocLine "</head>"
   addDocLine "<body>"
}

endDocument() {
   local file="${1}"

   addDocLine "</body>"
   addDocLine "</html>"

   exec 3>"${file}"
      local group

      for group in "${lineGroups[@]}"
      do
         eval set -- '"${'"${group}"'[@]}"'
         local line

         for line
         do
            echo >&3 "${line}"
         done
      done
   exec 3>&-
}

beginSection() {
   local title="${1}"

   local anchor="${title,,?}"
   anchor="${anchor//[^a-zA-Z_0-9]/-}"
   addAnchor "${anchor}"

   headerLevel=$((headerLevel + 1))
   addDocLine "<h${headerLevel}>${title}</h${headerLevel}>"

   if ((headerLevel == 1))
   then
      beginTocEntries tocSections
      addSectionTerminator
   else
      addTocEntry "${tocSections}" "${title}" "${anchor}"
   fi
}

endSection() {
   if ((headerLevel == 1))
   then
      endTocEntries "${tocSections}"
   else
      addSectionTerminator
   fi

   headerLevel=$((headerLevel - 1))
}

beginLayoutList() {
   layoutListed=false
}

endLayoutList() {
   ! "${layoutListed}" || {
      addDocLine "</ul>"
   }
}

beginLayoutEntry() {
   local prefix="${1}"
   local outputExtension="${2}"

   local layout="${inputFile##*/}"
   layout="${layout%.*}"

   outputFile="${outputRoot}/${prefix}-${layout}.${outputExtension}"
}

endLayoutEntry() {
   local category="${1}"

   exec 4<"${outputFile%.*}.${plainTextExtension}"
   local description
   read -r -u 4 description
   exec 4<&-

   description="${description} "
   description="${description#*: }"
   [ -z "${category}" ] || description="${description#${category} }"
   description="${description% }"

   local prefix="All Models"
   [ -z "${description}" ] || {
      if [ "${description}" = "${description#(}" ]
      then
         prefix=""
      else
         prefix="${prefix} "
      fi
   }
   description="${prefix}${description}"

   "${layoutListed}" || {
      layoutListed=true
      addDocLine "<ul>"
   }

   addDocLine "<li><a href=\"${outputFile##*/}\">${description}</a></li>"
}

listKeyTable() {
   local driver="${1}"

   local input="${inputFile##*/}"
   local output="${outputFile%.*}"
   local name="${output##*/}"

   local command=( "${keyTableLister}" -D"${buildRoot}/lib" -T"${sourceRoot}/${tablesSubdirectory}" )
   [ -n "${driver}" ] && command+=( -b "${driver}" )
   "${command[@]}" -l "${input}" >"${output}.${plainTextExtension}" || {
      rm -f "${output}.${plainTextExtension}"
      return 1
   }

   "${command[@]}" -r "${input}" >"${output}.${reStructuredTextExtension}"
   sed -e "2a\\${newLine}* \`Help Screen Version <${name}.${plainTextExtension}>\`_" -i "${output}.${reStructuredTextExtension}"

   rst2html --config "${sourceRoot}/docutils.conf" "${output}.${reStructuredTextExtension}" "${output}.${hypertextExtension}"
   "${keepFiles}" || rm "${output}.${reStructuredTextExtension}"
}

listBrailleKeyTables() {
   beginSection "Braille Device Key Bindings"
   addDocLine "The driver automatically selects the appropriate key table for the device model being used."
   addDocLine "Click on the driver's name for general information about it."
   addDocLine "Click on the device model for its key bindings."

   local tocDrivers
   beginTocEntries tocDrivers

   addDocLine "<dl>"
   local driverDirectory

   for driverDirectory in "${driversDirectory}/"*
   do
      [ -d "${driverDirectory}" ] || continue

      local driverName="${driverDirectory##*/}"
      local driverCode="$(sed -n '/^DRIVER_CODE *=/s/^.*= *\([^ ]*\).*$/\1/p' "${driverDirectory}/Makefile.in")"

      local header="${driverName}"
      local inputFile="${driverDirectory}/README"

      [ ! -f "${inputFile}" ] || {
         local outputFile="${outputRoot}/${braillePrefix}-${driverCode}.${plainTextExtension}"
         cp -a -- "${inputFile}" "${outputFile}"
         header="<a href=\"${outputFile##*/}\">${header}</a>"
      }

      local anchor="${braillePrefix}-${driverCode}"
      addTocEntry "${tocDrivers}" "${driverName}" "${anchor}"

      addDocLine "<dt>"
      addAnchor "${anchor}"
      addDocLine "${header}"
      addDocLine "</dt><dd>"

      beginLayoutList
      set -- "${tablesDirectory}/${brailleSubdirectory}/${driverCode}/"*".${keyTableExtension}"

      if [ "${#}" -gt 0 ]
      then
         for inputFile
         do
            beginLayoutEntry "${braillePrefix}-${driverCode}" "${hypertextExtension}"
            listKeyTable "${driverCode}" || continue
            endLayoutEntry "${driverName}"
         done
      else
         set -- "${tablesDirectory}/${brailleSubdirectory}/${driverCode}/"*".${plainTextExtension}"

         for inputFile
         do
            beginLayoutEntry "${braillePrefix}-${driverCode}" "${plainTextExtension}"
            cp -a -- "${inputFile}" "${outputFile}"
            endLayoutEntry "${driverName}"
         done
      fi

      endLayoutList
      addDocLine "</dd>"
   done

   addDocLine "</dl>"
   endTocEntries "${tocDrivers}"
   endSection
}

listKeyboardKeyTables() {
   beginSection "Keyboard Key Tables"
   addDocLine "In order to use one of these keyboard tables,"
   addDocLine "you need to explicitly specify it in one of the following ways:"

   addDocLine "<ul>"
   addDocLine "<li>Use BRLTTY's <tt>-k</tt> (or <tt>--keyboard-table=</tt>) command line option.</li>"
   addDocLine "<li>Use the <tt>keyboard-table</tt> configuration file (<tt>brltty.conf</tt>) directive.</li>"
   addDocLine "</ul>"

   beginLayoutList
   set -- "${tablesDirectory}/${keyboardSubdirectory}/"*".${keyTableExtension}"

   local inputFile
   for inputFile
   do
      beginLayoutEntry "${keyboardPrefix}" "${hypertextExtension}"
      listKeyTable || continue
      endLayoutEntry
   done

   endLayoutList
   endSection
}

driversSubdirectory="Drivers/Braille"
driversDirectory="${sourceRoot}/${driversSubdirectory}"

tablesSubdirectory="Tables"
tablesDirectory="${sourceRoot}/${tablesSubdirectory}"

brailleSubdirectory="Input"
keyboardSubdirectory="Keyboard"

braillePrefix="brl"
keyboardPrefix="kbd"

plainTextExtension="txt"
reStructuredTextExtension="rst"
hypertextExtension="html"
keyTableExtension="ktb"

keyTableLister="${buildRoot}/Programs/brltty-ktb"
make -C "${keyTableLister%/*}" -s "${keyTableLister##*/}"

documentTitle="Key Binding Lists"
beginDocument "${documentTitle}"

beginSection "${documentTitle}"
listBrailleKeyTables
listKeyboardKeyTables
endSection

endDocument "${outputRoot}/index.${hypertextExtension}"
exit 0