package org.broadinstitute.sting.alignment.bwa;

import org.broadinstitute.sting.alignment.Aligner;
import org.broadinstitute.sting.alignment.Alignment;
import org.broadinstitute.sting.utils.StingException;
import org.broadinstitute.sting.utils.BaseUtils;
import org.broadinstitute.sting.utils.fasta.IndexedFastaSequenceFile;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.List;

import net.sf.samtools.*;

/**
 * A test harness to ensure that the perfect aligner works.
 *
 * @author mhanna
 * @version 0.1
 */
public class AlignerTestHarness {
    public static void main( String argv[] ) throws FileNotFoundException {
        if( argv.length != 6 ) {
            System.out.println("PerfectAlignerTestHarness <fasta> <bwt> <rbwt> <sa> <rsa> <bam>");
            System.exit(1);
        }

        File referenceFile = new File(argv[0]);
        File bwtFile = new File(argv[1]);
        File rbwtFile = new File(argv[2]);
        File suffixArrayFile = new File(argv[3]);
        File reverseSuffixArrayFile = new File(argv[4]);
        File bamFile = new File(argv[5]);

        align(referenceFile,bwtFile,rbwtFile,suffixArrayFile,reverseSuffixArrayFile,bamFile);
    }

    private static void align(File referenceFile, File bwtFile, File rbwtFile, File suffixArrayFile, File reverseSuffixArrayFile, File bamFile) throws FileNotFoundException {
        Aligner aligner = new BWAAligner(bwtFile,rbwtFile,suffixArrayFile,reverseSuffixArrayFile);
        int count = 0;

        SAMFileReader reader = new SAMFileReader(bamFile);
        reader.setValidationStringency(SAMFileReader.ValidationStringency.SILENT);

        int mismatches = 0;
        int failures = 0;

        for(SAMRecord read: reader) {
            count++;
            //if( count > 100000 ) break;
            //if( count < 366000 ) continue;
            //if( count != 2 ) continue;
            //if( !read.getReadName().endsWith("SL-XBC:1:82:506:404#0") )
            //    continue;
            //if( !read.getReadName().endsWith("SL-XBC:1:36:30:1926#0") )
            //    continue;

            SAMRecord alignmentCleaned = null;
            try {
                alignmentCleaned = (SAMRecord)read.clone();
            }
            catch( CloneNotSupportedException ex ) {
                throw new StingException("SAMRecord clone not supported", ex);
            }

            if( alignmentCleaned.getReadNegativeStrandFlag() )
                alignmentCleaned.setReadBases(BaseUtils.simpleReverseComplement(alignmentCleaned.getReadBases()));

            alignmentCleaned.setReferenceIndex(SAMRecord.NO_ALIGNMENT_REFERENCE_INDEX);
            alignmentCleaned.setAlignmentStart(SAMRecord.NO_ALIGNMENT_START);
            alignmentCleaned.setMappingQuality(SAMRecord.NO_MAPPING_QUALITY);
            alignmentCleaned.setCigarString(SAMRecord.NO_ALIGNMENT_CIGAR);

            // Clear everything except flags pertaining to pairing and set 'unmapped' status to true.
            alignmentCleaned.setFlags(alignmentCleaned.getFlags() & 0x00A1 | 0x000C);

            List<Alignment> alignments = aligner.align(alignmentCleaned);
            if(alignments.size() == 0 ) {
                //throw new StingException(String.format("Unable to align read %s to reference; count = %d",read.getReadName(),count));
                System.out.printf("Unable to align read %s to reference; count = %d%n",read.getReadName(),count);
                failures++;
            }

            Alignment foundAlignment = null;
            for( Alignment alignment: alignments ) {
                if( read.getReadNegativeStrandFlag() != alignment.isNegativeStrand() )
                    continue;
                if( read.getAlignmentStart() != alignment.getAlignmentStart() )
                    continue;

                foundAlignment = alignment;
            }

            if( foundAlignment != null ) {
                //System.out.printf("%s: Aligned read to reference at position %d with %d mismatches, %d gap opens, and %d gap extensions.%n", read.getReadName(), foundAlignment.getAlignmentStart(), foundAlignment.getMismatches(), foundAlignment.getGapOpens(), foundAlignment.getGapExtensions());
            }
            else {
                System.out.printf("Error aligning read %s%n", read.getReadName());

                mismatches++;

                IndexedFastaSequenceFile reference = new IndexedFastaSequenceFile(referenceFile);

                System.out.printf("read          = %s, position = %d, negative strand = %b%n", formatBasesBasedOnCigar(read.getReadString(),read.getCigar(),CigarOperator.DELETION),
                                                                                               read.getAlignmentStart(),
                                                                                               read.getReadNegativeStrandFlag());
                int numDeletions = numDeletionsInCigar(read.getCigar());
                String expectedRef = new String(reference.getSubsequenceAt(reference.getSequenceDictionary().getSequences().get(0).getSequenceName(),read.getAlignmentStart(),read.getAlignmentStart()+read.getReadLength()+numDeletions-1).getBases());
                System.out.printf("expected ref  = %s%n", formatBasesBasedOnCigar(expectedRef,read.getCigar(),CigarOperator.INSERTION));

                for( Alignment alignment: alignments ) {
                    System.out.println();

                    Cigar cigar = ((BWAAlignment)alignment).getCigar();

                    System.out.printf("read          = %s%n", formatBasesBasedOnCigar(read.getReadString(),cigar,CigarOperator.DELETION));

                    int deletionCount = ((BWAAlignment)alignment).getNumberOfBasesMatchingState(AlignmentState.DELETION);
                    String alignedRef = new String(reference.getSubsequenceAt(reference.getSequenceDictionary().getSequences().get(0).getSequenceName(),alignment.getAlignmentStart(),alignment.getAlignmentStart()+read.getReadLength()+deletionCount-1).getBases());
                    System.out.printf("actual ref    = %s, position = %d, negative strand = %b%n", formatBasesBasedOnCigar(alignedRef,cigar,CigarOperator.INSERTION),
                                                                                                   alignment.getAlignmentStart(),
                                                                                                   alignment.isNegativeStrand());
                }

                //throw new StingException(String.format("Read %s was placed at incorrect location; count = %d%n",read.getReadName(),count));                
            }


            if( count % 1000 == 0 )
                System.out.printf("%d reads examined.%n",count);                
        }

        System.out.printf("%d reads examined; %d mismatches; %d failures.%n",count,mismatches,failures);
    }

    private static String formatBasesBasedOnCigar( String bases, Cigar cigar, CigarOperator toBlank ) {
        StringBuilder formatted = new StringBuilder();
        int readIndex = 0;
        for(CigarElement cigarElement: cigar.getCigarElements()) {
            if(cigarElement.getOperator() == toBlank) {
                int number = cigarElement.getLength();
                while( number-- > 0 ) formatted.append(' ');
            }
            else {
                int number = cigarElement.getLength();
                while( number-- > 0 ) formatted.append(bases.charAt(readIndex++));
            }
        }
        return formatted.toString();
    }

    private static int numDeletionsInCigar( Cigar cigar ) {
        int numDeletions = 0;
        for(CigarElement cigarElement: cigar.getCigarElements()) {
            if(cigarElement.getOperator() == CigarOperator.DELETION)
                numDeletions += cigarElement.getLength();
        }
        return numDeletions;
    }
}