/*
 tests/test_numpy_array.cpp -- test core array functionality

 Copyright (c) 2016 Ivan Smirnov <i.s.smirnov@gmail.com>

 All rights reserved. Use of this source code is governed by a
 BSD-style license that can be found in the LICENSE file.
*/

#include <pybind11/numpy.h>
#include <pybind11/stl.h>

#include "pybind11_tests.h"

#include <cstdint>
#include <utility>

// Size / dtype checks.
struct DtypeCheck {
 py::dtype numpy{};
 py::dtype pybind11{};
};

template <typename T>
DtypeCheck get_dtype_check(const char *name) {
 py::module_ np = py::module_::import("numpy");
 DtypeCheck check{};
 check.numpy = np.attr("dtype")(np.attr(name));
 check.pybind11 = py::dtype::of<T>();
 return check;
}

std::vector<DtypeCheck> get_concrete_dtype_checks() {
 return {// Normalization
 get_dtype_check<std::int8_t>("int8"),
 get_dtype_check<std::uint8_t>("uint8"),
 get_dtype_check<std::int16_t>("int16"),
 get_dtype_check<std::uint16_t>("uint16"),
 get_dtype_check<std::int32_t>("int32"),
 get_dtype_check<std::uint32_t>("uint32"),
 get_dtype_check<std::int64_t>("int64"),
 get_dtype_check<std::uint64_t>("uint64")};
}

struct DtypeSizeCheck {
 std::string name{};
 int size_cpp{};
 int size_numpy{};
 // For debugging.
 py::dtype dtype{};
};

template <typename T>
DtypeSizeCheck get_dtype_size_check() {
 DtypeSizeCheck check{};
 check.name = py::type_id<T>();
 check.size_cpp = sizeof(T);
 check.dtype = py::dtype::of<T>();
 check.size_numpy = check.dtype.attr("itemsize").template cast<int>();
 return check;
}

std::vector<DtypeSizeCheck> get_platform_dtype_size_checks() {
 return {
 get_dtype_size_check<short>(),
 get_dtype_size_check<unsigned short>(),
 get_dtype_size_check<int>(),
 get_dtype_size_check<unsigned int>(),
 get_dtype_size_check<long>(),
 get_dtype_size_check<unsigned long>(),
 get_dtype_size_check<long long>(),
 get_dtype_size_check<unsigned long long>(),
 };
}

// Arrays.
using arr = py::array;
using arr_t = py::array_t<uint16_t, 0>;
static_assert(std::is_same<arr_t::value_type, uint16_t>::value, "");

template <typename... Ix>
arr data(const arr &a, Ix... index) {
 return arr(a.nbytes() - a.offset_at(index...), (const uint8_t *) a.data(index...));
}

template <typename... Ix>
arr data_t(const arr_t &a, Ix... index) {
 return arr(a.size() - a.index_at(index...), a.data(index...));
}

template <typename... Ix>
arr &mutate_data(arr &a, Ix... index) {
 auto *ptr = (uint8_t *) a.mutable_data(index...);
 for (py::ssize_t i = 0; i < a.nbytes() - a.offset_at(index...); i++) {
 ptr[i] = (uint8_t) (ptr[i] * 2);
 }
 return a;
}

template <typename... Ix>
arr_t &mutate_data_t(arr_t &a, Ix... index) {
 auto ptr = a.mutable_data(index...);
 for (py::ssize_t i = 0; i < a.size() - a.index_at(index...); i++) {
 ptr[i]++;
 }
 return a;
}

template <typename... Ix>
py::ssize_t index_at(const arr &a, Ix... idx) {
 return a.index_at(idx...);
}
template <typename... Ix>
py::ssize_t index_at_t(const arr_t &a, Ix... idx) {
 return a.index_at(idx...);
}
template <typename... Ix>
py::ssize_t offset_at(const arr &a, Ix... idx) {
 return a.offset_at(idx...);
}
template <typename... Ix>
py::ssize_t offset_at_t(const arr_t &a, Ix... idx) {
 return a.offset_at(idx...);
}
template <typename... Ix>
py::ssize_t at_t(const arr_t &a, Ix... idx) {
 return a.at(idx...);
}
template <typename... Ix>
arr_t &mutate_at_t(arr_t &a, Ix... idx) {
 a.mutable_at(idx...)++;
 return a;
}

#define def_index_fn(name, type) \
 sm.def(#name, [](type a) { return name(a); }); \
 sm.def(#name, [](type a, int i) { return name(a, i); }); \
 sm.def(#name, [](type a, int i, int j) { return name(a, i, j); }); \
 sm.def(#name, [](type a, int i, int j, int k) { return name(a, i, j, k); });

template <typename T, typename T2>
py::handle auxiliaries(T &&r, T2 &&r2) {
 if (r.ndim() != 2) {
 throw std::domain_error("error: ndim != 2");
 }
 py::list l;
 l.append(*r.data(0, 0));
 l.append(*r2.mutable_data(0, 0));
 l.append(r.data(0, 1) == r2.mutable_data(0, 1));
 l.append(r.ndim());
 l.append(r.itemsize());
 l.append(r.shape(0));
 l.append(r.shape(1));
 l.append(r.size());
 l.append(r.nbytes());
 return l.release();
}

// note: declaration at local scope would create a dangling reference!
static int data_i = 42;

TEST_SUBMODULE(numpy_array, sm) {
 try {
 py::module_::import("numpy");
 } catch (const py::error_already_set &) {
 return;
 }

 // test_dtypes
 py::class_<DtypeCheck>(sm, "DtypeCheck")
 .def_readonly("numpy", &DtypeCheck::numpy)
 .def_readonly("pybind11", &DtypeCheck::pybind11)
 .def("__repr__", [](const DtypeCheck &self) {
 return py::str("<DtypeCheck numpy={} pybind11={}>").format(self.numpy, self.pybind11);
 });
 sm.def("get_concrete_dtype_checks", &get_concrete_dtype_checks);

 py::class_<DtypeSizeCheck>(sm, "DtypeSizeCheck")
 .def_readonly("name", &DtypeSizeCheck::name)
 .def_readonly("size_cpp", &DtypeSizeCheck::size_cpp)
 .def_readonly("size_numpy", &DtypeSizeCheck::size_numpy)
 .def("__repr__", [](const DtypeSizeCheck &self) {
 return py::str("<DtypeSizeCheck name='{}' size_cpp={} size_numpy={} dtype={}>")
 .format(self.name, self.size_cpp, self.size_numpy, self.dtype);
 });
 sm.def("get_platform_dtype_size_checks", &get_platform_dtype_size_checks);

 // test_array_attributes
 sm.def("ndim", [](const arr &a) { return a.ndim(); });
 sm.def("shape", [](const arr &a) { return arr(a.ndim(), a.shape()); });
 sm.def("shape", [](const arr &a, py::ssize_t dim) { return a.shape(dim); });
 sm.def("strides", [](const arr &a) { return arr(a.ndim(), a.strides()); });
 sm.def("strides", [](const arr &a, py::ssize_t dim) { return a.strides(dim); });
 sm.def("writeable", [](const arr &a) { return a.writeable(); });
 sm.def("size", [](const arr &a) { return a.size(); });
 sm.def("itemsize", [](const arr &a) { return a.itemsize(); });
 sm.def("nbytes", [](const arr &a) { return a.nbytes(); });
 sm.def("owndata", [](const arr &a) { return a.owndata(); });

 // test_index_offset
 def_index_fn(index_at, const arr &);
 def_index_fn(index_at_t, const arr_t &);
 def_index_fn(offset_at, const arr &);
 def_index_fn(offset_at_t, const arr_t &);
 // test_data
 def_index_fn(data, const arr &);
 def_index_fn(data_t, const arr_t &);
 // test_mutate_data, test_mutate_readonly
 def_index_fn(mutate_data, arr &);
 def_index_fn(mutate_data_t, arr_t &);
 def_index_fn(at_t, const arr_t &);
 def_index_fn(mutate_at_t, arr_t &);

 // test_make_c_f_array
 sm.def("make_f_array", [] { return py::array_t<float>({2, 2}, {4, 8}); });
 sm.def("make_c_array", [] { return py::array_t<float>({2, 2}, {8, 4}); });

 // test_empty_shaped_array
 sm.def("make_empty_shaped_array", [] { return py::array(py::dtype("f"), {}, {}); });
 // test numpy scalars (empty shape, ndim==0)
 sm.def("scalar_int", []() { return py::array(py::dtype("i"), {}, {}, &data_i); });

 // test_wrap
 sm.def("wrap", [](const py::array &a) {
 return py::array(a.dtype(),
 {a.shape(), a.shape() + a.ndim()},
 {a.strides(), a.strides() + a.ndim()},
 a.data(),
 a);
 });

 // test_numpy_view
 struct ArrayClass {
 int data[2] = {1, 2};
 ArrayClass() { py::print("ArrayClass()"); }
 ~ArrayClass() { py::print("~ArrayClass()"); }
 };
 py::class_<ArrayClass>(sm, "ArrayClass")
 .def(py::init<>())
 .def("numpy_view", [](py::object &obj) {
 py::print("ArrayClass::numpy_view()");
 auto &a = obj.cast<ArrayClass &>();
 return py::array_t<int>({2}, {4}, a.data, obj);
 });

 // test_cast_numpy_int64_to_uint64
 sm.def("function_taking_uint64", [](uint64_t) {});

 // test_isinstance
 sm.def("isinstance_untyped", [](py::object yes, py::object no) {
 return py::isinstance<py::array>(std::move(yes))
 && !py::isinstance<py::array>(std::move(no));
 });
 sm.def("isinstance_typed", [](const py::object &o) {
 return py::isinstance<py::array_t<double>>(o) && !py::isinstance<py::array_t<int>>(o);
 });

 // test_constructors
 sm.def("default_constructors", []() {
 return py::dict("array"_a = py::array(),
 "array_t<int32>"_a = py::array_t<std::int32_t>(),
 "array_t<double>"_a = py::array_t<double>());
 });
 sm.def("converting_constructors", [](const py::object &o) {
 return py::dict("array"_a = py::array(o),
 "array_t<int32>"_a = py::array_t<std::int32_t>(o),
 "array_t<double>"_a = py::array_t<double>(o));
 });

 // test_overload_resolution
 sm.def("overloaded", [](const py::array_t<double> &) { return "double"; });
 sm.def("overloaded", [](const py::array_t<float> &) { return "float"; });
 sm.def("overloaded", [](const py::array_t<int> &) { return "int"; });
 sm.def("overloaded", [](const py::array_t<unsigned short> &) { return "unsigned short"; });
 sm.def("overloaded", [](const py::array_t<long long> &) { return "long long"; });
 sm.def("overloaded",
 [](const py::array_t<std::complex<double>> &) { return "double complex"; });
 sm.def("overloaded", [](const py::array_t<std::complex<float>> &) { return "float complex"; });

 sm.def("overloaded2",
 [](const py::array_t<std::complex<double>> &) { return "double complex"; });
 sm.def("overloaded2", [](const py::array_t<double> &) { return "double"; });
 sm.def("overloaded2",
 [](const py::array_t<std::complex<float>> &) { return "float complex"; });
 sm.def("overloaded2", [](const py::array_t<float> &) { return "float"; });

 // [workaround(intel)] ICC 20/21 breaks with py::arg().stuff, using py::arg{}.stuff works.

 // Only accept the exact types:
 sm.def(
 "overloaded3", [](const py::array_t<int> &) { return "int"; }, py::arg{}.noconvert());
 sm.def(
 "overloaded3",
 [](const py::array_t<double> &) { return "double"; },
 py::arg{}.noconvert());

 // Make sure we don't do unsafe coercion (e.g. float to int) when not using forcecast, but
 // rather that float gets converted via the safe (conversion to double) overload:
 sm.def("overloaded4", [](const py::array_t<long long, 0> &) { return "long long"; });
 sm.def("overloaded4", [](const py::array_t<double, 0> &) { return "double"; });

 // But we do allow conversion to int if forcecast is enabled (but only if no overload matches
 // without conversion)
 sm.def("overloaded5", [](const py::array_t<unsigned int> &) { return "unsigned int"; });
 sm.def("overloaded5", [](const py::array_t<double> &) { return "double"; });

 // test_greedy_string_overload
 // Issue 685: ndarray shouldn't go to std::string overload
 sm.def("issue685", [](const std::string &) { return "string"; });
 sm.def("issue685", [](const py::array &) { return "array"; });
 sm.def("issue685", [](const py::object &) { return "other"; });

 // test_array_unchecked_fixed_dims
 sm.def(
 "proxy_add2",
 [](py::array_t<double> a, double v) {
 auto r = a.mutable_unchecked<2>();
 for (py::ssize_t i = 0; i < r.shape(0); i++) {
 for (py::ssize_t j = 0; j < r.shape(1); j++) {
 r(i, j) += v;
 }
 }
 },
 py::arg{}.noconvert(),
 py::arg());

 sm.def("proxy_init3", [](double start) {
 py::array_t<double, py::array::c_style> a({3, 3, 3});
 auto r = a.mutable_unchecked<3>();
 for (py::ssize_t i = 0; i < r.shape(0); i++) {
 for (py::ssize_t j = 0; j < r.shape(1); j++) {
 for (py::ssize_t k = 0; k < r.shape(2); k++) {
 r(i, j, k) = start++;
 }
 }
 }
 return a;
 });
 sm.def("proxy_init3F", [](double start) {
 py::array_t<double, py::array::f_style> a({3, 3, 3});
 auto r = a.mutable_unchecked<3>();
 for (py::ssize_t k = 0; k < r.shape(2); k++) {
 for (py::ssize_t j = 0; j < r.shape(1); j++) {
 for (py::ssize_t i = 0; i < r.shape(0); i++) {
 r(i, j, k) = start++;
 }
 }
 }
 return a;
 });
 sm.def("proxy_squared_L2_norm", [](const py::array_t<double> &a) {
 auto r = a.unchecked<1>();
 double sumsq = 0;
 for (py::ssize_t i = 0; i < r.shape(0); i++) {
 sumsq += r[i] * r(i); // Either notation works for a 1D array
 }
 return sumsq;
 });

 sm.def("proxy_auxiliaries2", [](py::array_t<double> a) {
 auto r = a.unchecked<2>();
 auto r2 = a.mutable_unchecked<2>();
 return auxiliaries(r, r2);
 });

 sm.def("proxy_auxiliaries1_const_ref", [](py::array_t<double> a) {
 const auto &r = a.unchecked<1>();
 const auto &r2 = a.mutable_unchecked<1>();
 return r(0) == r2(0) && r[0] == r2[0];
 });

 sm.def("proxy_auxiliaries2_const_ref", [](py::array_t<double> a) {
 const auto &r = a.unchecked<2>();
 const auto &r2 = a.mutable_unchecked<2>();
 return r(0, 0) == r2(0, 0);
 });

 // test_array_unchecked_dyn_dims
 // Same as the above, but without a compile-time dimensions specification:
 sm.def(
 "proxy_add2_dyn",
 [](py::array_t<double> a, double v) {
 auto r = a.mutable_unchecked();
 if (r.ndim() != 2) {
 throw std::domain_error("error: ndim != 2");
 }
 for (py::ssize_t i = 0; i < r.shape(0); i++) {
 for (py::ssize_t j = 0; j < r.shape(1); j++) {
 r(i, j) += v;
 }
 }
 },
 py::arg{}.noconvert(),
 py::arg());
 sm.def("proxy_init3_dyn", [](double start) {
 py::array_t<double, py::array::c_style> a({3, 3, 3});
 auto r = a.mutable_unchecked();
 if (r.ndim() != 3) {
 throw std::domain_error("error: ndim != 3");
 }
 for (py::ssize_t i = 0; i < r.shape(0); i++) {
 for (py::ssize_t j = 0; j < r.shape(1); j++) {
 for (py::ssize_t k = 0; k < r.shape(2); k++) {
 r(i, j, k) = start++;
 }
 }
 }
 return a;
 });
 sm.def("proxy_auxiliaries2_dyn", [](py::array_t<double> a) {
 return auxiliaries(a.unchecked(), a.mutable_unchecked());
 });

 sm.def("array_auxiliaries2", [](py::array_t<double> a) { return auxiliaries(a, a); });

 // test_array_failures
 // Issue #785: Uninformative "Unknown internal error" exception when constructing array from
 // empty object:
 sm.def("array_fail_test", []() { return py::array(py::object()); });
 sm.def("array_t_fail_test", []() { return py::array_t<double>(py::object()); });
 // Make sure the error from numpy is being passed through:
 sm.def("array_fail_test_negative_size", []() {
 int c = 0;
 return py::array(-1, &c);
 });

 // test_initializer_list
 // Issue (unnumbered; reported in #788): regression: initializer lists can be ambiguous
 sm.def("array_initializer_list1", []() { return py::array_t<float>(1); });
 // { 1 } also works for the above, but clang warns about it
 sm.def("array_initializer_list2", []() { return py::array_t<float>({1, 2}); });
 sm.def("array_initializer_list3", []() { return py::array_t<float>({1, 2, 3}); });
 sm.def("array_initializer_list4", []() { return py::array_t<float>({1, 2, 3, 4}); });

 // test_array_resize
 // reshape array to 2D without changing size
 sm.def("array_reshape2", [](py::array_t<double> a) {
 const auto dim_sz = (py::ssize_t) std::sqrt(a.size());
 if (dim_sz * dim_sz != a.size()) {
 throw std::domain_error(
 "array_reshape2: input array total size is not a squared integer");
 }
 a.resize({dim_sz, dim_sz});
 });

 // resize to 3D array with each dimension = N
 sm.def("array_resize3", [](py::array_t<double> a, size_t N, bool refcheck) {
 a.resize({N, N, N}, refcheck);
 });

 // test_array_create_and_resize
 // return 2D array with Nrows = Ncols = N
 sm.def("create_and_resize", [](size_t N) {
 py::array_t<double> a;
 a.resize({N, N});
 std::fill(a.mutable_data(), a.mutable_data() + a.size(), 42.);
 return a;
 });

 sm.def("array_view",
 [](py::array_t<uint8_t> a, const std::string &dtype) { return a.view(dtype); });

 sm.def("reshape_initializer_list", [](py::array_t<int> a, size_t N, size_t M, size_t O) {
 return a.reshape({N, M, O});
 });
 sm.def("reshape_tuple", [](py::array_t<int> a, const std::vector<int> &new_shape) {
 return a.reshape(new_shape);
 });

 sm.def("index_using_ellipsis",
 [](const py::array &a) { return a[py::make_tuple(0, py::ellipsis(), 0)]; });

 // test_argument_conversions
 sm.def(
 "accept_double", [](const py::array_t<double, 0> &) {}, py::arg("a"));
 sm.def(
 "accept_double_forcecast",
 [](const py::array_t<double, py::array::forcecast> &) {},
 py::arg("a"));
 sm.def(
 "accept_double_c_style",
 [](const py::array_t<double, py::array::c_style> &) {},
 py::arg("a"));
 sm.def(
 "accept_double_c_style_forcecast",
 [](const py::array_t<double, py::array::forcecast | py::array::c_style> &) {},
 py::arg("a"));
 sm.def(
 "accept_double_f_style",
 [](const py::array_t<double, py::array::f_style> &) {},
 py::arg("a"));
 sm.def(
 "accept_double_f_style_forcecast",
 [](const py::array_t<double, py::array::forcecast | py::array::f_style> &) {},
 py::arg("a"));
 sm.def(
 "accept_double_noconvert", [](const py::array_t<double, 0> &) {}, "a"_a.noconvert());
 sm.def(
 "accept_double_forcecast_noconvert",
 [](const py::array_t<double, py::array::forcecast> &) {},
 "a"_a.noconvert());
 sm.def(
 "accept_double_c_style_noconvert",
 [](const py::array_t<double, py::array::c_style> &) {},
 "a"_a.noconvert());
 sm.def(
 "accept_double_c_style_forcecast_noconvert",
 [](const py::array_t<double, py::array::forcecast | py::array::c_style> &) {},
 "a"_a.noconvert());
 sm.def(
 "accept_double_f_style_noconvert",
 [](const py::array_t<double, py::array::f_style> &) {},
 "a"_a.noconvert());
 sm.def(
 "accept_double_f_style_forcecast_noconvert",
 [](const py::array_t<double, py::array::forcecast | py::array::f_style> &) {},
 "a"_a.noconvert());

 // Check that types returns correct npy format descriptor
 sm.def("test_fmt_desc_float", [](const py::array_t<float> &) {});
 sm.def("test_fmt_desc_double", [](const py::array_t<double> &) {});
 sm.def("test_fmt_desc_const_float", [](const py::array_t<const float> &) {});
 sm.def("test_fmt_desc_const_double", [](const py::array_t<const double> &) {});
}