#!/usr/bin/env ruby

#    ratexdb Version 0.14
#    Database Access in LaTeX
#    Copyright (C) 2007-2010 Robin Höns, Integranova GmbH
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
#
#    For more information see the web pages
#
#    Robin Höns: http://www.hoens.net/robin
#    Integranova and the Programming Machine:
#                http://www.programmiermaschine.de
#                http://www.care-t.com

require 'dbi'
require 'FileUtils'


$filedebug = nil

# primitive debug output routine
def debugoutput line
  if $filedebug
    $filedebug.puts "#{line}" 
  end
end



def replace_latex dbtext
# Replace Latex special characters in DB result
#Unterstrich 	_ 	\_
#Rückstrich\Backslash 	\ 	\setminus
#Dollarzeichen 	$ 	\$
#Kaufmanns-Und 	& 	\&
#Raute 	# 	\#
#Geschweifte Klammern 	{ } 	\{ \}
#Prozentzeichen 	 % 	\%
  debugoutput "replatex rein: " + dbtext

  specialhash = {
    ?\\ => "\\\\ensuremath{\\\\backslash}",
    ?_ => "\\\\_",
    ?$ => "\\\\$",
    ?& => "\\\\&",
    ?# => "\\\\#",
    ?{ => "\\\\{",
    ?} => "\\\\}",
    ?~ => "\\\\~{}",
    ?% => "\\\\%"
  }

  result = ""

  for i in (0..dbtext.length)
    maski = specialhash[dbtext[i]]
    if maski
      result << maski
    else
      result << dbtext[i,1]
    end
  end
 
  debugoutput "replatex raus: " + result

  return result
end

def replace_sql dbtext
# Replace SQL special characters in DB result
# (important against SQL injection!)
  return dbtext.gsub("'", "''")
end

def check_number dbtext
# This text must contain a single numeric value
# (important against SQL injection!)
  unless dbtext =~ /\A(\+|-)?[\da-fA-F]+\Z/
    raise "Numeric variable contains non-numeric value: #{dbtext}"
  end
  return dbtext
end


def execute_if texblock
  debugoutput "Pruefe if #{$select_to_handle}"
  debugoutput texblock

  selectkram = $select_hash[$select_to_handle]
  $select_to_handle = nil
  $modus_collect = false

  selectbefehl = selectkram[0]
  debugoutput "Select: #{selectbefehl}"
  row = $dbconn.select_one( selectbefehl )

  if row
    # Ja, es gibt Daten zu diesem Select
    for nowline in texblock.split("\n")
      debugoutput "nowline " + nowline
      handle_line(nowline)
    end
  end
end


def execute_for_loop texblock

  debugoutput "Mache #{$select_to_handle} mit:"
  debugoutput texblock

  selectkram = $select_hash[$select_to_handle]
  $select_to_handle = nil
  $modus_collect = false

  selectbefehl = selectkram[0]
  variablen = selectkram[1]

  debugoutput "Select: #{selectbefehl}"
  for myvar in variablen
    debugoutput "Var: #{myvar}"
  end

  rows = $dbconn.select_all( selectbefehl )

  for row in rows
    ergebnis = texblock
    vari = 0
    while vari < variablen.length
      variable_regexs = variablen[vari].split("/")
      varname = variable_regexs[0]

      debugoutput "ok: " + varname
      if varname[0,2] != "##"
        raise "Variable #{varname} does not begin with ##"
      end
      varnamesql = "$$" + varname[2..-1]
      varnamenum = "&&" + varname[2..-1]

      original_db_result = row[vari].to_s
      current_db_result_latex = replace_latex(original_db_result)
      current_db_result_sql = replace_sql(original_db_result)
      if ergebnis.index(varnamenum)
            current_db_result_num = check_number(original_db_result)
      else
            current_db_result_num = original_db_result
      end

      debugoutput "latex: #{current_db_result_latex}"
      debugoutput "sql: #{current_db_result_sql}"
      debugoutput "num: #{current_db_result_num}"

      # Perform all Regexp replaces
      rei = 2
      while rei < variable_regexs.length
      debugoutput variable_regexs[rei-1]
        rei_regex = Regexp.new( variable_regexs[rei-1] )
      debugoutput rei_regex
        rei_replace = variable_regexs[rei]
      debugoutput rei_replace
        current_db_result_latex = current_db_result_latex.gsub(rei_regex, rei_replace)
        current_db_result_sql = current_db_result_sql.gsub(rei_regex, rei_replace)
        current_db_result_num = current_db_result_num.gsub(rei_regex, rei_replace)

      debugoutput "latex: #{current_db_result_latex}"
      debugoutput "sql: #{current_db_result_sql}"
      debugoutput "num: #{current_db_result_num}"

        rei += 2
      end

# Handle the three variable flavours
      ergebnis = ergebnis.gsub(varname, current_db_result_latex)
      ergebnis = ergebnis.gsub(varnamesql, current_db_result_sql)
      if ergebnis.index(varnamenum)
        ergebnis = ergebnis.gsub(varnamenum, current_db_result_num)
      end

      vari += 1
    end
    debugoutput "Ergebnis: #{ergebnis}"
    for nowline in ergebnis.split("\n")
      handle_line(nowline)
    end
  end
end

def execute_defselect texblock
  debugoutput "defselect #{$select_to_define}"
  debugoutput texblock

  $defining_select_statement = texblock

end


def execute_defvariablen texblock
  debugoutput "defvariablen #{$select_to_define}"
  debugoutput texblock

  # remove all white space from variable list

  varliste = Array.new

  for var in texblock.split(",")
    varliste << var.strip
  end

  varliste.each {|var| debugoutput "Got Var: " + var}

  $select_hash[$select_to_define] = [$defining_select_statement, varliste]

  $select_to_define = nil
  $modus_collect = false
end


def handle_line_unless_empty(line)
  debugoutput "handle unless empty"
  unless line == nil
    unless line.length == 0
      debugoutput "Handle: " + line
      handle_line line
    else
#      debugoutput "line is empty"
    end
  else
#    debugoutput "line is nil"
  end
end

def handle_line(line)
#  debugoutput "Handle: " + line

##  matchDef=/\A([^%]*)\\texdbdef\{##([^\}]*)\}\{(.*)\}\{(.*)\}(.*)/
  matchDef=/\A([^%]*)\\texdbdef\{##([^\}]*)\}\{(.*)/
##  matchFor=/\A(.*)\\texdbfor\{##([^\}]*)\}\{(.*)\}(.*)/
  matchFor=/\A([^%]*)\\texdbfor\{##([^\}]*)\}\{(.*)/
  matchIf=/\A([^%]*)\\texdbif\{##([^\}]*)\}\{(.*)/
  matchDbDef=/\A([^%]*)\\texdbconnection\{([^\}]*)\}(.*)/
  matchDbCmd=/\A([^%]*)\\texdbcommand\{([^\}]*)\}(.*)/

  if $modus_collect == false
    if line =~ matchDef
      debugoutput "Found Def!"
      handle_line_unless_empty($1)
      $select_to_define = $2
      $bracedepth = 1
      $modus_collect = 1
      $collected_text = ""
      $kommando="defselect"
      handle_line_unless_empty($3)
    elsif line =~ matchFor
      debugoutput "Found For!"
      handle_line_unless_empty($1)
      $select_to_handle = $2
      $bracedepth = 1
      $modus_collect = 1
      $collected_text = ""
      $kommando="for"
      handle_line_unless_empty($3)
    elsif line =~ matchIf
      debugoutput "Found If!"
      handle_line_unless_empty($1)
      $select_to_handle = $2
      $bracedepth = 1
      $modus_collect = 1
      $collected_text = ""
      $kommando="if"
      handle_line_unless_empty($3)
    elsif line =~ matchDbDef
      debugoutput "Found DbDef!"
      handle_line_unless_empty($1)
      debugoutput "Datenbank: #{$2}"
      dbpar = $2.split(",")
      $dbconn = DBI.connect(dbpar[0], dbpar[1], dbpar[2], dbpar[3])
      handle_line_unless_empty($3)
    elsif line =~ matchDbCmd
      debugoutput "Found DbCmd!"
      handle_line_unless_empty($1)
      debugoutput "Command: #{$2}"
      unless $dbconn 
        raise "Please put texdbconnection before texdbcommand!"
      end
      sth = $dbconn.execute($2)
      sth.finish
      handle_line_unless_empty($3)
    else
      $fileout.puts "#{line}"
    end
  else
    # wir sammeln Zeilen

    if line == nil
      linelength = 0
    else
      linelength = line.length
    end
#    debugoutput linelength
    i = 0
    backslashgelesen = 0
    while i < linelength && $bracedepth > 0
      currchar = line[i]
#      debugoutput "curr #{currchar} backsl #{backslashgelesen}"
      if currchar == ?\\
        if backslashgelesen == 0 
          backslashgelesen = 1
        else
          backslashgelesen = 0
        end
      elsif currchar == ?{
        if backslashgelesen == 0 
          $bracedepth += 1
          debugoutput "Tiefe: #{$bracedepth}"
        else
          debugoutput "kein ++, Backslash!"
        end
        backslashgelesen = 0
      elsif currchar == ?}
        if backslashgelesen == 0 
          $bracedepth -= 1
          debugoutput "Tiefe: #{$bracedepth}"
        else
          debugoutput "kein --, Backslash!"
        end
        backslashgelesen = 0
      else
        backslashgelesen = 0
      end
      i += 1
    end # while
    debugoutput "Zeile Tiefe: #{$bracedepth}"
    $collected_text << line[0, i]
    i -= 1

    if $bracedepth == 0 
      # chop, um } wegzuschmeißen
      if $kommando == "for"
        execute_for_loop $collected_text.chop
        $modus_collect = false
      elsif $kommando == "if"
        execute_if $collected_text.chop
        $modus_collect = false
      elsif $kommando == "defselect"
        execute_defselect $collected_text.chop
        i += 1
        if i >= linelength || line[i] != ?{
          raise "In texdbdef of #{$select_to_define} there is nothing allowed between the select and variable block, but I did not find the \}\{."
        end
        $modus_collect = 1
        $kommando = "defvariablen"
        $bracedepth = 1
        $collected_text = ""
      elsif $kommando == "defvariablen"
        execute_defvariablen $collected_text.chop
        $modus_collect = false
      end

      handle_line_unless_empty line[i+1 .. -1]
    end

    $collected_text << "\n"

  end
end

def output_help

  puts "Ratexdb 0.14 Copyright (C) 2007-2010 Robin Hoens, Integranova GmbH"
  puts "This program comes with ABSOLUTELY NO WARRANTY."
  puts "This is free software, and you are welcome to redistribute it"
  puts "under certain conditions."
  puts "See file COPYING for details."
  puts ""
  puts "Usage:"
  puts "#{$0} [-p|-l] <texfile.tex> [Parameters...]"
  puts "-p = pdflatex"
  puts "-l = latex"
  puts "none of the two: just produce texfile1.tex"
  exit
end


if ARGV.length == 0
  output_help
end

arg_index = 0

before_texfile = 1

while before_texfile
  if ARGV[arg_index] == "-p"
    texbefehl = "pdflatex"
    resultextension = ".pdf"  
  elsif ARGV[arg_index] == "-l"
    texbefehl = "latex"
    resultextension = ".dvi"  
  elsif ARGV[arg_index] == "-d"
    $filedebug = File.new("ratexdb.txt", "w")
  else
    before_texfile = false
  end
  arg_index += 1  
  if ARGV.length < arg_index
    output_help
  end
end

arg_index -= 1  

datei_rein = ARGV[arg_index]
datei_raus = datei_rein.sub(/\.tex\Z/, "1.tex")

if datei_raus == datei_rein
  raise "Sorry: File name must end on .tex. I got #{datei_rein}"
end

debugoutput datei_rein
debugoutput datei_raus

$select_to_handle = nil
$select_hash = {}
$variable_hash = {}
$modus_collect = false

cmdlinehash = {}
i=1
while arg_index + i < ARGV.length
  cmdlinehash[i.to_s] = ARGV[arg_index + i]
  i+=1      
end

filein = File.new(datei_rein, "r")
$fileout = File.new(datei_raus, "w")
while (line = filein.gets)
  cmdlinehash.each {|key, value| 
      line = line.gsub("##" + key, replace_latex(value))
      line = line.gsub("$$" + key, replace_sql(value))
      if line.index("&&" + key)
        line = line.gsub("&&" + key, check_number(value))
      end
  }
  handle_line line.chomp
end
filein.close
$fileout.close

$dbconn.disconnect if $dbconn

if texbefehl
  system(texbefehl, datei_raus)

  rauspdf = datei_raus.sub(/\.tex\Z/, resultextension)
  ergebnispdf = datei_rein.sub(/\.tex\Z/, resultextension)

  File.mv(rauspdf, ergebnispdf)
end