#!/bin/ksh
#
# Generates database specific static stubb file from
# the given SQL filenames
#
# Usage: create_static_stubb [-c|-v] database_name [sql_files]
#
# Output file is called : <database_name>_Sstatic.c
#
# If -c option is used (MUST BE the first arg), 
#    then the created C-code will be compiled with $ODB_CC (if ODB_CC is defined)
#    If compilation successful, then the object will be put into lib<dbname>.a (if available)
# If -v option is used (MUST BE the first arg),
#    then the viewnames associated (found) in the given SQL-file are written to stdout
#

set -eu

usage="Usage: $0 [-c|-v] database_name [sql_files]"

if [[ $# -lt 1 ]] ; then
  echo "$usage" >&2
  exit 1
fi

compile=0
vn=0

if [[ "$1" = "-c" ]] ; then
  compile=1
  shift
elif [[ "$1" = "-v" ]] ; then
  vn=1
  shift
fi

if [[ $# -lt 1 ]] ; then
  echo "$usage" >&2
  exit 2
fi

db=$1
shift

if [[ $# -ge 1 ]] ; then
  sql_files=$*
else
  sql_files=$(\ls [a-z]*.sql 2>/dev/null || :)
fi

if [[ $compile -eq 1 ]] ; then
  stubb_file=${db}_Sstatic.c
else
  stubb_file=${db}_Sstatic.c.new
fi
stubb_obj=${db}_Sstatic.o
stubb_tmp=${db}_Sstatic.c.tmp

cat > $stubb_file <<EOF
#define ODB_GENCODE 0
#include "${db}.h"

PUBLIC void ${db}_static_init() {
ODB_ANCHOR(${db});
EOF

export ODB_AR=${ODB_AR:="ar"}

libname=lib$db.a
testvar=ODB_SRCPATH_${db}
set +u
testvalue=$(eval echo \$$testvar 2>/dev/null || :)
if [[ "$testvalue" != "" && -d "$testvalue" ]] ; then
  libname=$testvalue/lib$db.a
else
  testvalue=""
fi
set -u

#-- Preserve pre-existing views from previous compilation(s) (except if -v given)
cat /dev/null > $stubb_tmp
if [[ $vn -eq 0 && -r $libname ]] ; then
  $ODB_AR t $libname | perl -pe "s/^${db}_//; s/[.]o//;" |\
                       egrep -v "^(T_|Sstatic|${db})" > $stubb_tmp
fi

set +u
for sql in $sql_files
do
  if [[ -r "$sql" && "$sql" != "/dev/null" ]] ; then
#    s=$(basename $sql .sql)
#    set -A v $(\cat $sql | perl -ne 'print "\L$1 " if (/CREATE\s+VIEW\s+(\w+)/i);')
    set -A v $(perl -ne 'print "\L$1\n" if(/^\s*CREATE\s*VIEW\s+(\S+)/i);' $sql |\
               perl -pe 's/(\w+)\s*\[\s*(-?\d+)\s*\].*/$1_$2/; s/-/_/g;')
#    echo "v=${v[*]}"
#    echo "no. of v=${#v[*]}"
    if [[ ${#v[*]} -gt 0 ]] ; then
      for s in ${v[*]}
      do
        echo "$s" >> $stubb_tmp
      done
    else # Probably a direct select ... from ... ?
      s=$(basename $sql .sql | perl -pe 'tr/A-Z/a-z/')
      echo "ODB_ANCHOR_VIEW(${db}, $s );" >> $stubb_file
      # count number of selects. if more than 1, make also views _tmp_1, _tmp_2, etc.
      n=$(\cat $sql | perl -ne 'BEGIN {$n=0} $n++ if (m/^.*\bselect\b.*/i); END {print $n}')
      if [[ $n -gt 1 ]] ; then
        j=1;
        while [[ $j -lt $n ]] # < $n, since first view is already per .sql-file basename
        do
          echo "_tmp_$j" >> $stubb_tmp
          ((j += 1))
        done
      fi
    fi
  fi
done
set -u

for s in $(sort -u $stubb_tmp)
do
  echo "ODB_ANCHOR_VIEW(${db}, $s );" >> $stubb_file
done
\rm -f $stubb_tmp

echo '}' >> $stubb_file

rc=0

if [[ $compile -eq 1 ]] ; then
  export ODB_CC=${ODB_CC:=""}
  libname=lib$db.a
  if [[ "$ODB_CC" != "" ]] ; then
    if [[ "$testvalue" != "" ]] ; then
      export ODB_CC="${ODB_CC:=cc} -I$testvalue"
    fi
    echo "$ODB_CC -c $stubb_file" >&2
          $ODB_CC -c $stubb_file  >&2 || rc=$?
    if [[ $rc -eq 0 && -f $stubb_obj && -f $libname ]] ; then
      $ODB_AR r $libname $stubb_obj || rc=$?
    fi
  fi
elif [[ $vn -eq 1 ]] ; then
  egrep ODB_ANCHOR_VIEW $stubb_file >/dev/null 2>&1 || rc=$?
  egrep ODB_ANCHOR_VIEW $stubb_file 2>/dev/null | awk '{print $2}'
  \rm -f $stubb_file  
else # Create the final stubb-file only if it
     # (1) does not exist already or
     # (2) new differs from the existing one
  rename=0
  true_stubb_file=${db}_Sstatic.c
  if [[ -f $true_stubb_file ]] ; then
    diff -q $true_stubb_file $stubb_file >/dev/null 2>&1 || rename=1
  else
    rename=1
  fi
  if [[ $rename -eq 1 ]] ; then
    \rm -f $true_stubb_file
    \mv $stubb_file $true_stubb_file
  else
    \rm -f $stubb_file
  fi
fi

exit $rc