var log = console.log
    , assert = require( 'assert' )
    , Qap = require( '../' )
    , mb = 300
    , pmb = 20
    , dlen = mb * 1024 * 1024
    , plen = pmb * 1024 * 1024
    , pattern = new Buffer( plen )
    , data = new Buffer( dlen )
    , i = 0
    , rand = 0
    , qap = null
    , indexes = []
    , results = null
    , otime = 0
    , ttime = 0
    , stime = 0
    , etime = 0
    // pre-process time
    , pptime = 0
    // memory usage
    , smem = null
    , emem = null
    ;


log( '- benchmark for worst case with a big pattern, not sparse in data' );

stime = Date.now();
for ( ; i < plen; ++i ) {
    rand = Math.floor( Math.random() * 255 * plen ) % 255;
    pattern[ i ] = rand; 
}
log( '- created %d MB big pattern in %d secs', pmb, ( ( Date.now()- stime ) / 1000 ).toFixed( 1 ) );

smem = process.memoryUsage();

otime = Date.now();
stime = Date.now();
qap = Qap( pattern );
pptime = ( ( Date.now()- stime ) / 1000 ).toFixed( 1 );
emem = process.memoryUsage();
log( '- big pattern pre-processed in %d secs', pptime );

log( '- allocating %d MB of data', mb );
stime = Date.now();
for ( i = 0; i <= dlen - plen; i += 1.2 * plen ) {
    pattern.copy( data, i );
    indexes.push( i );
}
log( '- test data buffer (' + mb + 'MB) created in', ( Date.now() - stime ) / 1000, 'secs' );
log( '- copied', ( indexes.length ) , 'big patterns (' + pmb + 'MB) in test data' );

stime = Date.now();
results = qap.parse( data );
etime = ( Date.now() - stime ) / 1000;
ttime = ( Date.now() - otime ) / 1000;
log( '- test data was parsed in', etime, 'secs' );

log( '- check if results length is equal to', indexes.length );
assert.equal( results.length, indexes.length );

log( '- compare results and pre-defined indexes' );
assert.deepEqual( results, indexes );

log( '- pre-processing data rate is:', ( 8 * mb / pptime / 1024 ).toFixed( 2 ), 'Gbit/sec' );
log( '- parsing data rate is:', ( 8 * mb / etime / 1024 ).toFixed( 4 ), 'Gbit/sec' );
log( '- total elapsed time:', ttime.toFixed( 2 ), 'secs' );
log( '- resulting data-rate:', ( ( 8 * mb / ttime / 1024 ) ).toFixed( 4 ), 'Gbit/sec' );

log( '- tables memory usage is %d KBytes', ( ( emem.rss - smem.rss ) / 1024 ).toFixed( 1 ) );
log( '- tables v8++ heap usage is %d KBytes', ( ( emem.heapUsed - smem.heapUsed ) / 1024 ).toFixed( 1 ) );