/**
 * UGENE - Integrated Bioinformatics Tools.
 * Copyright (C) 2008-2021 UniPro <ugene@unipro.ru>
 * http://ugene.net
 *
 * 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 2
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 */

#include "AssemblyConsensusAlgorithmSamtools.h"
#include <SamtoolsAdapter.h>
#include <cstring>
#include <stdio.h>

#include "BuiltInAssemblyConsensusAlgorithms.h"
extern "C" {
#include <bam2bcf.h>
}
#include <U2Core/Log.h>
#include <U2Core/U2Assembly.h>
#include <U2Core/U2SafePoints.h>

namespace U2 {

//////////////////////////////////////////////////////////////////////////
// Factory

AssemblyConsensusAlgorithmFactorySamtools::AssemblyConsensusAlgorithmFactorySamtools()
    : AssemblyConsensusAlgorithmFactory(BuiltInAssemblyConsensusAlgorithms::SAMTOOLS_ALGO) {
}

QString AssemblyConsensusAlgorithmFactorySamtools::getName() const {
    return tr("SAMtools");
}

QString AssemblyConsensusAlgorithmFactorySamtools::getDescription() const {
    return tr("Uses SAMtools to calculate consensus with regard to quality of reads");
}

AssemblyConsensusAlgorithm *AssemblyConsensusAlgorithmFactorySamtools::createAlgorithm() {
    return new AssemblyConsensusAlgorithmSamtools(this);
}

//////////////////////////////////////////////////////////////////////////
// Algorithm

struct AlgorithmInternal {
    AlgorithmInternal(const U2Region &region_, QByteArray referenceFragment_, U2OpStatus &os_)
        : region(region_), os(os_), referenceFragment(referenceFragment_), result(region_.length, AssemblyConsensusAlgorithm::EMPTY_CHAR) {
        lplbuf = bam_lplbuf_init(processBaseCallback, this);
        bam_lplbuf_reset(lplbuf);

        bca = bcf_call_init(0.83, 13);
    }

    void processReads(U2DbiIterator<U2AssemblyRead> *reads) {
        ReadsContainer samtoolsReads;
        os.setDescription(AssemblyConsensusAlgorithmFactorySamtools::tr("Fetching reads from database and converting to SAMtools format"));
        SamtoolsAdapter::reads2samtools(reads, os, samtoolsReads);
        CHECK_OP(os, );
        os.setDescription(AssemblyConsensusAlgorithmFactorySamtools::tr("Sorting reads"));
        samtoolsReads.sortByStartPos();

        os.setDescription(AssemblyConsensusAlgorithmFactorySamtools::tr("Calculating consensus"));
        const int readsCount = samtoolsReads.size();
        for (int i = 0; i < readsCount; ++i) {
            bam_lplbuf_push(&samtoolsReads[i], lplbuf);
            os.setProgress(i * 100 / readsCount);
            CHECK_OP(os, );
        }
        bam_lplbuf_push(0, lplbuf);
    }

    void processBase(uint32_t /*tid*/, uint32_t pos, int n, const bam_pileup1_t *pl) {
        if (pos < region.startPos || pos >= region.endPos() || os.isCoR()) {
            return;
        }
        uint32_t posInArray = pos - region.startPos;
        // From bam_tview.c, tv_pl_func function
        int i, j, rb;
        uint32_t call = 0;
        bcf_callret1_t bcr;

        rb = referenceFragment.isEmpty() ? 'N' : referenceFragment[posInArray];

        int qsum[4], a1, a2, tmp;
        double p[3], prior = 30;
        bcf_call_glfgen(n, pl, bam_nt16_table[rb], bca, &bcr);

        for (i = 0; i < 4; ++i)
            qsum[i] = bcr.qsum[i] << 2 | i;
        for (i = 1; i < 4; ++i)    // insertion sort
            for (j = i; j > 0 && qsum[j] > qsum[j - 1]; --j)
                tmp = qsum[j], qsum[j] = qsum[j - 1], qsum[j - 1] = tmp;
        a1 = qsum[0] & 3;
        a2 = qsum[1] & 3;
        p[0] = bcr.p[a1 * 5 + a1];
        p[1] = bcr.p[a1 * 5 + a2] + prior;
        p[2] = bcr.p[a2 * 5 + a2];
        if ("ACGT"[a1] != toupper(rb))
            p[0] += prior + 3;
        if ("ACGT"[a2] != toupper(rb))
            p[2] += prior + 3;
        if (p[0] < p[1] && p[0] < p[2])
            call = (1 << a1) << 16 | (int)((p[1] < p[2] ? p[1] : p[2]) - p[0] + .499);
        else if (p[2] < p[1] && p[2] < p[0])
            call = (1 << a2) << 16 | (int)((p[0] < p[1] ? p[0] : p[1]) - p[2] + .499);
        else
            call = (1 << a1 | 1 << a2) << 16 | (int)((p[0] < p[2] ? p[0] : p[2]) - p[1] + .499);

        char consensusChar = bam_nt16_rev_table[call >> 16 & 0xf];
        result[posInArray] = consensusChar;
    }

    static int processBaseCallback(uint32_t tid, uint32_t pos, int n, const bam_pileup1_t *pl, void *data) {
        AlgorithmInternal *algorithm = (AlgorithmInternal *)data;
        algorithm->processBase(tid, pos, n, pl);
        return 0;
    }

    QByteArray getResult() {
        return result;
    }

    ~AlgorithmInternal() {
        bcf_call_destroy(bca);
        bam_lplbuf_destroy(lplbuf);
    }

private:
    const U2Region &region;
    U2OpStatus &os;
    QByteArray referenceFragment;
    bam_lplbuf_t *lplbuf;
    bcf_callaux_t *bca;
    QByteArray result;
};

QByteArray AssemblyConsensusAlgorithmSamtools::getConsensusRegion(const U2Region &region, U2DbiIterator<U2AssemblyRead> *reads, QByteArray referenceFragment, U2OpStatus &os) {
    AlgorithmInternal algorithm(region, referenceFragment, os);

    algorithm.processReads(reads);

    return algorithm.getResult();
}

}    // namespace U2
