/* ************************************************************************
 * Copyright 2016-2021 Advanced Micro Devices, Inc.
 *
 * ************************************************************************ */

#include <fstream>
#include <iostream>
#include <stdlib.h>
#include <vector>

#include "testing_common.hpp"

using namespace std;

/* ============================================================================================ */

template <typename T>
hipblasStatus_t testing_tbsv_strided_batched(const Arguments& argus)
{
    bool FORTRAN = argus.fortran;
    auto hipblasTbsvStridedBatchedFn
        = FORTRAN ? hipblasTbsvStridedBatched<T, true> : hipblasTbsvStridedBatched<T, false>;

    int                M            = argus.M;
    int                K            = argus.K;
    int                incx         = argus.incx;
    int                lda          = argus.lda;
    char               char_uplo    = argus.uplo_option;
    char               char_diag    = argus.diag_option;
    char               char_transA  = argus.transA_option;
    hipblasFillMode_t  uplo         = char2hipblas_fill(char_uplo);
    hipblasDiagType_t  diag         = char2hipblas_diagonal(char_diag);
    hipblasOperation_t transA       = char2hipblas_operation(char_transA);
    double             stride_scale = argus.stride_scale;
    int                batch_count  = argus.batch_count;

    int           abs_incx = incx < 0 ? -incx : incx;
    hipblasStride strideA  = size_t(M) * M;
    hipblasStride strideAB = size_t(M) * lda * stride_scale;
    hipblasStride stridex  = size_t(abs_incx) * M * stride_scale;
    size_t        size_A   = strideA * batch_count;
    size_t        size_AB  = strideAB * batch_count;
    size_t        size_x   = stridex * batch_count;

    hipblasLocalHandle handle(argus);

    // argument sanity check, quick return if input parameters are invalid before allocating invalid
    // memory
    bool invalid_size = M < 0 || K < 0 || lda < K + 1 || !incx || batch_count < 0;
    if(invalid_size || !M || !batch_count)
    {
        hipblasStatus_t actual = hipblasTbsvStridedBatchedFn(handle,
                                                             uplo,
                                                             transA,
                                                             diag,
                                                             M,
                                                             K,
                                                             nullptr,
                                                             lda,
                                                             strideA,
                                                             nullptr,
                                                             incx,
                                                             stridex,
                                                             batch_count);
        EXPECT_HIPBLAS_STATUS(
            actual, (invalid_size ? HIPBLAS_STATUS_INVALID_VALUE : HIPBLAS_STATUS_SUCCESS));
        return actual;
    }

    // Naming: dK is in GPU (device) memory. hK is in CPU (host) memory
    host_vector<T> hA(size_A);
    host_vector<T> hAB(size_AB);
    host_vector<T> AAT(size_A);
    host_vector<T> hb(size_x);
    host_vector<T> hx(size_x);
    host_vector<T> hx_or_b_1(size_x);

    device_vector<T> dAB(size_AB);
    device_vector<T> dx_or_b(size_x);

    double gpu_time_used, hipblas_error, cumulative_hipblas_error = 0;

    // Initial Data on CPU
    srand(1);
    hipblas_init<T>(hA, M, M, M, strideA, batch_count);
    hipblas_init<T>(hx, 1, M, abs_incx, stridex, batch_count);
    hb = hx;

    for(int b = 0; b < batch_count; b++)
    {
        T* hAbat  = hA.data() + b * strideA;
        T* hABbat = hAB.data() + b * strideAB;
        T* AATbat = AAT.data() + b * strideA;
        T* hbbat  = hb.data() + b * stridex;
        banded_matrix_setup(uplo == HIPBLAS_FILL_MODE_UPPER, hAbat, M, M, K);

        prepare_triangular_solve(hAbat, M, AATbat, M, char_uplo);
        if(diag == HIPBLAS_DIAG_UNIT)
        {
            make_unit_diagonal(uplo, hAbat, M, M);
        }

        regular_to_banded(uplo == HIPBLAS_FILL_MODE_UPPER, hAbat, M, hABbat, lda, M, K);

        // Calculate hb = hA*hx;
        cblas_tbmv<T>(uplo, transA, diag, M, K, hABbat, lda, hbbat, incx);
    }

    hx_or_b_1 = hb;

    // copy data from CPU to device
    CHECK_HIP_ERROR(hipMemcpy(dAB, hAB.data(), sizeof(T) * size_AB, hipMemcpyHostToDevice));
    CHECK_HIP_ERROR(
        hipMemcpy(dx_or_b, hx_or_b_1.data(), sizeof(T) * size_x, hipMemcpyHostToDevice));

    /* =====================================================================
           HIPBLAS
    =================================================================== */
    if(argus.unit_check || argus.norm_check)
    {
        CHECK_HIPBLAS_ERROR(hipblasTbsvStridedBatchedFn(handle,
                                                        uplo,
                                                        transA,
                                                        diag,
                                                        M,
                                                        K,
                                                        dAB,
                                                        lda,
                                                        strideAB,
                                                        dx_or_b,
                                                        incx,
                                                        stridex,
                                                        batch_count));

        // copy output from device to CPU
        CHECK_HIP_ERROR(
            hipMemcpy(hx_or_b_1.data(), dx_or_b, sizeof(T) * size_x, hipMemcpyDeviceToHost));

        // Calculating error
        // For norm_check/bench, currently taking the cumulative sum of errors over all batches
        for(int b = 0; b < batch_count; b++)
        {
            hipblas_error = std::abs(vector_norm_1<T>(
                M, abs_incx, hx.data() + b * stridex, hx_or_b_1.data() + b * stridex));
            if(argus.unit_check)
            {
                double tolerance = std::numeric_limits<real_t<T>>::epsilon() * 40 * M;
                unit_check_error(hipblas_error, tolerance);
            }

            cumulative_hipblas_error += hipblas_error;
        }
    }

    if(argus.timing)
    {
        hipStream_t stream;
        CHECK_HIPBLAS_ERROR(hipblasGetStream(handle, &stream));

        int runs = argus.cold_iters + argus.iters;
        for(int iter = 0; iter < runs; iter++)
        {
            if(iter == argus.cold_iters)
                gpu_time_used = get_time_us_sync(stream);

            CHECK_HIPBLAS_ERROR(hipblasTbsvStridedBatchedFn(handle,
                                                            uplo,
                                                            transA,
                                                            diag,
                                                            M,
                                                            K,
                                                            dAB,
                                                            lda,
                                                            strideAB,
                                                            dx_or_b,
                                                            incx,
                                                            stridex,
                                                            batch_count));
        }
        gpu_time_used = get_time_us_sync(stream) - gpu_time_used; // in microseconds

        ArgumentModel<e_uplo_option,
                      e_transA_option,
                      e_diag_option,
                      e_M,
                      e_K,
                      e_lda,
                      e_incx,
                      e_stride_x,
                      e_batch_count>{}
            .log_args<T>(std::cout,
                         argus,
                         gpu_time_used,
                         tbsv_gflop_count<T>(M, K),
                         tbsv_gbyte_count<T>(M, K),
                         cumulative_hipblas_error);
    }

    return HIPBLAS_STATUS_SUCCESS;
}