/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013, 2014 Damien P. George
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdlib.h>
#include <assert.h>

#include "py/obj.h"
#include "py/runtime.h"
#include "py/runtime0.h"

#include "supervisor/shared/translate.h"

/******************************************************************************/
/* slice object */

#if MICROPY_PY_BUILTINS_SLICE

// TODO: This implements only variant of slice with 2 integer args only.
// CPython supports 3rd arg (step), plus args can be arbitrary Python objects.
typedef struct _mp_obj_slice_t {
 mp_obj_base_t base;
 mp_obj_t start;
 mp_obj_t stop;
 mp_obj_t step;
} mp_obj_slice_t;

STATIC void slice_print(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind) {
 (void)kind;
 mp_obj_slice_t *o = MP_OBJ_TO_PTR(o_in);
 mp_print_str(print, "slice(");
 mp_obj_print_helper(print, o->start, PRINT_REPR);
 mp_print_str(print, ", ");
 mp_obj_print_helper(print, o->stop, PRINT_REPR);
 mp_print_str(print, ", ");
 mp_obj_print_helper(print, o->step, PRINT_REPR);
 mp_print_str(print, ")");
}

#if MICROPY_PY_BUILTINS_SLICE_ATTRS
STATIC mp_obj_t slice_indices(mp_obj_t self_in, mp_obj_t length_obj) {
 mp_obj_slice_t *self = MP_OBJ_TO_PTR(self_in);
 if (!MP_OBJ_IS_SMALL_INT(length_obj)) {
 mp_raise_TypeError(translate("Length must be an int"));
 }

 int length = MP_OBJ_SMALL_INT_VALUE(length_obj);
 if (length < 0) {
 mp_raise_ValueError(translate("Length must be non-negative"));
 }

 mp_obj_t indices[3] = {MP_OBJ_NEW_SMALL_INT(0), length_obj, MP_OBJ_NEW_SMALL_INT(1)};
 mp_obj_t slice[2] = {self->start, self->stop};

 int step = 1;
 if (self->step != mp_const_none) {
 indices[2] = self->step;
 step = MP_OBJ_SMALL_INT_VALUE(self->step);
 if (step < 0) {
 indices[0] = MP_OBJ_NEW_SMALL_INT(length - 1);
 indices[1] = MP_OBJ_NEW_SMALL_INT(-1);
 }
 if (step == 0) {
 mp_raise_ValueError(translate("slice step cannot be zero"));
 }
 }
 for (int i = 0; i < 2; i++) {
 if (slice[i] == mp_const_none) {
 continue;
 }
 int value = MP_OBJ_SMALL_INT_VALUE(slice[i]);
 if (value < 0) {
 value += length;
 }
 if (value < 0) {
 if (step > 0) {
 value = 0;
 } else if (step < 0) {
 value = -1;
 }
 } else if (value > length) {
 value = length;
 }
 indices[i] = MP_OBJ_NEW_SMALL_INT(value);
 }

 mp_obj_t tuple = mp_obj_new_tuple(3, indices);

 return tuple;
}
MP_DEFINE_CONST_FUN_OBJ_2(slice_indices_obj, slice_indices);

STATIC void slice_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
 if (dest[0] != MP_OBJ_NULL) {
 // not load attribute
 return;
 }
 mp_obj_slice_t *self = MP_OBJ_TO_PTR(self_in);
 if (attr == MP_QSTR_start) {
 dest[0] = self->start;
 } else if (attr == MP_QSTR_stop) {
 dest[0] = self->stop;
 } else if (attr == MP_QSTR_step) {
 dest[0] = self->step;
 } else if (attr == MP_QSTR_indices) {
 mp_convert_member_lookup(self_in, self->base.type, (mp_obj_t) &slice_indices_obj, dest);
 }
}

STATIC mp_obj_t slice_make_new(const mp_obj_type_t *type,
 size_t n_args, const mp_obj_t *args, mp_map_t *kw_args);
#endif

const mp_obj_type_t mp_type_slice = {
 { &mp_type_type },
 .name = MP_QSTR_slice,
 .print = slice_print,
#if MICROPY_PY_BUILTINS_SLICE_ATTRS
 .make_new = slice_make_new,
 .attr = slice_attr,
#endif
};

mp_obj_t mp_obj_new_slice(mp_obj_t ostart, mp_obj_t ostop, mp_obj_t ostep) {
 mp_obj_slice_t *o = m_new_obj(mp_obj_slice_t);
 o->base.type = &mp_type_slice;
 o->start = ostart;
 o->stop = ostop;
 o->step = ostep;
 return MP_OBJ_FROM_PTR(o);
}

// Return the real index and step values for a slice when applied to a sequence of
// the given length, resolving missing components, negative values and values off
// the end of the sequence.
void mp_obj_slice_indices(mp_obj_t self_in, mp_int_t length, mp_bound_slice_t *result) {
 mp_obj_slice_t *self = MP_OBJ_TO_PTR(self_in);
 mp_int_t start, stop, step;

 if (self->step == mp_const_none) {
 step = 1;
 } else {
 step = mp_obj_get_int(self->step);
 if (step == 0) {
 mp_raise_ValueError(translate("slice step cannot be zero"));
 }
 }

 if (step > 0) {
 // Positive step
 if (self->start == mp_const_none) {
 start = 0;
 } else {
 start = mp_obj_get_int(self->start);
 if (start < 0) {
 start += length;
 }
 start = MIN(length, MAX(start, 0));
 }

 if (self->stop == mp_const_none) {
 stop = length;
 } else {
 stop = mp_obj_get_int(self->stop);
 if (stop < 0) {
 stop += length;
 }
 stop = MIN(length, MAX(stop, 0));
 }
 } else {
 // Negative step
 if (self->start == mp_const_none) {
 start = length - 1;
 } else {
 start = mp_obj_get_int(self->start);
 if (start < 0) {
 start += length;
 }
 start = MIN(length - 1, MAX(start, -1));
 }

 if (self->stop == mp_const_none) {
 stop = -1;
 } else {
 stop = mp_obj_get_int(self->stop);
 if (stop < 0) {
 stop += length;
 }
 stop = MIN(length - 1, MAX(stop, -1));
 }
 }

 result->start = start;
 result->stop = stop;
 result->step = step;
}

#if MICROPY_PY_BUILTINS_SLICE_ATTRS
STATIC mp_obj_t slice_make_new(const mp_obj_type_t *type,
 size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
 if (type != &mp_type_slice) {
 mp_raise_NotImplementedError(translate("Cannot subclass slice"));
 }
 // check number of arguments
 mp_arg_check_num(n_args, kw_args, 1, 3, false);

 // 1st argument is the pin
 mp_obj_t start = mp_const_none;
 mp_obj_t stop = mp_const_none;
 mp_obj_t step = mp_const_none;
 if (n_args == 1) {
 stop = args[0];
 } else {
 start = args[0];
 stop = args[1];
 if (n_args == 3) {
 step = args[2];
 }
 }

 return mp_obj_new_slice(start, stop, step);
}
#endif

void mp_obj_slice_get(mp_obj_t self_in, mp_obj_t *start, mp_obj_t *stop, mp_obj_t *step) {
 assert(MP_OBJ_IS_TYPE(self_in, &mp_type_slice));
 mp_obj_slice_t *self = MP_OBJ_TO_PTR(self_in);
 *start = self->start;
 *stop = self->stop;
 *step = self->step;
}

#endif