#!/bin/bash
#
# convert a database from MySQL to SQLite

echo -ne "Database: "
read db
echo -ne "User: "
read user
echo -ne "Password: "
read -s pw
echo ""

# remove files from previous runs
rm -f $db.sql $db.sqlite $db.db $db.err

echo "Dumping MySQL DB \"$db\" to file $db.sql..."
mysqldump -u $user -p$pw --compatible=ansi --skip-opt --default-character-set=utf8 $db > $db.sql || exit 10

echo "Converting SQL dump ($db.sql) to SQLite dump ($db.sqlite)..."
cat $db.sql |
grep -v ' KEY "' |
grep -v ' UNIQUE KEY "' |
grep -v ' PRIMARY KEY ' |
sed '/^SET/d' |
sed 's/ unsigned / /gI' |
sed 's/ auto_increment/ primary key autoincrement/gI' |
sed 's/ smallint([0-9]*) / integer /gI' |
sed 's/ tinyint([0-9]*) / integer /gI' |
sed 's/ int([0-9]*) / integer /gI' |
sed 's/ enum([^)]*) / varchar(255) /gI' |
sed 's/ on update [^,]*//gI' |
sed 's/\\r\\n/\\n/g' |
sed 's/\\"/"/g' |
sed -r 's/ character set [^, ]* ?/ /gI' |
sed -r 's/ collate [^, ]* ?/ /gI' |
perl -e 'local $/;$_=<>;s/,\n\)/\n\)/gs;print "begin;\n";print;print "commit;\n"' |
perl -pe '
if (/^(INSERT.+?)\(/) {
  $a=$db;
  s/\\'\''/'\'\''/g;
  s/\\'\'\','/'\','/g;
  s/\\n/\n/g;
  s/\),\(/\);\n$a\(/g;
}
' > $db.sqlite

echo "Importing SQLite dump to $db.db..."
cat $db.sqlite | sqlite3 $db.db 2> $db.err
ERRORS=`cat $db.err | wc -l`
if [ $ERRORS == 0 ]; then
  echo "Conversion completed without errors. Output file: $db.db"
  rm -f $db.sql $db.sqlite $db.err
else
  echo "There were errors during conversion. Please review $db.err and $db.sqlite for details."
fi