/*******************************************************
 * Copyright (c) 2014, ArrayFire
 * All rights reserved.
 *
 * This file is distributed under 3-clause BSD license.
 * The complete license agreement can be obtained at:
 * http://arrayfire.com/licenses/BSD-3-Clause
 ********************************************************/

#include <af/array.h>
#include <af/signal.h>
#include <af/defines.h>
#include <common/err_common.hpp>
#include <handle.hpp>
#include <backend.hpp>
#include <common/ArrayInfo.hpp>
#include <approx.hpp>

using af::dim4;
using namespace detail;

template<typename Ty, typename Tp>
static inline af_array approx1(const af_array in, const af_array pos,
                               const af_interp_type method, const float offGrid)
{
    return getHandle(approx1<Ty>(getArray<Ty>(in), getArray<Tp>(pos), method, offGrid));
}

template<typename Ty, typename Tp>
static inline af_array approx2(const af_array in, const af_array pos0, const af_array pos1,
                               const af_interp_type method, const float offGrid)
{
    return getHandle(approx2<Ty>(getArray<Ty>(in), getArray<Tp>(pos0), getArray<Tp>(pos1),
                                 method, offGrid));
}

af_err af_approx1(af_array *out, const af_array in, const af_array pos,
                  const af_interp_type method, const float offGrid)
{
    try {
        const ArrayInfo& i_info = getInfo(in);
        const ArrayInfo& p_info = getInfo(pos);

        dim4 idims = i_info.dims();
        dim4 pdims = p_info.dims();

        af_dtype itype = i_info.getType();

        ARG_ASSERT(1, i_info.isFloating());                       // Only floating and complex types
        ARG_ASSERT(2, p_info.isRealFloating());                   // Only floating types
        ARG_ASSERT(1, i_info.isSingle() == p_info.isSingle());    // Must have same precision
        ARG_ASSERT(1, i_info.isDouble() == p_info.isDouble());    // Must have same precision
        // POS should either be (x, 1, 1, 1) or (1, idims[1], idims[2], idims[3])
        DIM_ASSERT(2, p_info.isColumn() ||
                      (pdims[1] == idims[1] && pdims[2] == idims[2] && pdims[3] == idims[3]));
        ARG_ASSERT(3, (method == AF_INTERP_LINEAR  ||
                       method == AF_INTERP_NEAREST ||
                       method == AF_INTERP_CUBIC   ||
                       method == AF_INTERP_CUBIC_SPLINE ||
                       method == AF_INTERP_LINEAR_COSINE ||
                       method == AF_INTERP_LOWER));

        if(idims.ndims() == 0 || pdims.ndims() ==  0) {
            return af_create_handle(out, 0, nullptr, itype);
        }

        af_array output;

        switch(itype) {
            case f32: output = approx1<float  , float >(in, pos, method, offGrid);  break;
            case f64: output = approx1<double , double>(in, pos, method, offGrid);  break;
            case c32: output = approx1<cfloat , float >(in, pos, method, offGrid);  break;
            case c64: output = approx1<cdouble, double>(in, pos, method, offGrid);  break;
            default:  TYPE_ERROR(1, itype);
        }
        std::swap(*out,output);
    }
    CATCHALL;

    return AF_SUCCESS;
}

af_err af_approx2(af_array *out, const af_array in, const af_array pos0, const af_array pos1,
                  const af_interp_type method, const float offGrid)
{
    try {
        const ArrayInfo& i_info = getInfo(in);
        const ArrayInfo& p_info = getInfo(pos0);
        const ArrayInfo& q_info = getInfo(pos1);

        dim4 idims = i_info.dims();
        dim4 pdims = p_info.dims();
        dim4 qdims = q_info.dims();

        af_dtype itype = i_info.getType();

        ARG_ASSERT(1, i_info.isFloating());                     // Only floating and complex types
        ARG_ASSERT(2, p_info.isRealFloating());                 // Only floating types
        ARG_ASSERT(3, q_info.isRealFloating());                 // Only floating types
        ARG_ASSERT(1, p_info.getType() == q_info.getType());    // Must have same type
        ARG_ASSERT(1, i_info.isSingle() == p_info.isSingle());  // Must have same precision
        ARG_ASSERT(1, i_info.isDouble() == p_info.isDouble());  // Must have same precision
        DIM_ASSERT(2, pdims == qdims);                          // POS0 and POS1 must have same dims

        // POS should either be (x, y, 1, 1) or (x, y, idims[2], idims[3])
        DIM_ASSERT(2, (pdims[2] == 1        && pdims[3] == 1) ||
                      (pdims[2] == idims[2] && pdims[3] == idims[3]));

        if(idims.ndims() == 0 || pdims.ndims() ==  0 || qdims.ndims() == 0) {
            return af_create_handle(out, 0, nullptr, itype);
        }

        af_array output;

        switch(itype) {
            case f32: output = approx2<float  , float >(in, pos0, pos1, method, offGrid);  break;
            case f64: output = approx2<double , double>(in, pos0, pos1, method, offGrid);  break;
            case c32: output = approx2<cfloat , float >(in, pos0, pos1, method, offGrid);  break;
            case c64: output = approx2<cdouble, double>(in, pos0, pos1, method, offGrid);  break;
            default:  TYPE_ERROR(1, itype);
        }
        std::swap(*out,output);
    }
    CATCHALL;

    return AF_SUCCESS;
}
