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/**
* @license Apache-2.0
*
* Copyright (c) 2023 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
 
'use strict';
 
// MODULES //
 
var isMostlySafeCast = require( '@stdlib/ndarray/base/assert/is-mostly-safe-data-type-cast' );
var broadcast = require( '@stdlib/ndarray/base/broadcast-array' );
var assign = require( '@stdlib/ndarray/base/assign' );
var slice = require( '@stdlib/ndarray/base/slice' );
var getDType = require( '@stdlib/ndarray/base/dtype' );
var getShape = require( '@stdlib/ndarray/base/shape' );
var format = require( '@stdlib/string/format' );
 
 
// MAIN //
 
/**
* Assigns element values from a broadcasted input ndarray to corresponding elements in an output ndarray view.
*
* @param {ndarray} x - input array
* @param {ndarray} y - output array
* @param {MultiSlice} s - multi-slice object for the output array
* @param {boolean} strict - boolean indicating whether to enforce strict bounds checking
* @throws {RangeError} number of slice dimensions must match the number of array dimensions
* @throws {RangeError} slice exceeds array bounds
* @throws {Error} input array must be broadcast compatible with an output array view
* @throws {TypeError} input array cannot be safely cast to the output array data type
* @returns {ndarray} output array
*
* @example
* var Slice = require( '@stdlib/slice/ctor' );
* var MultiSlice = require( '@stdlib/slice/multi' );
* var ndarray = require( '@stdlib/ndarray/ctor' );
* var ndzeros = require( '@stdlib/ndarray/zeros' );
* var ndarray2array = require( '@stdlib/ndarray/to-array' );
*
* // Define an input array:
* var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
* var shape = [ 3, 2 ];
* var strides = [ 2, 1 ];
* var offset = 0;
*
* var x = ndarray( 'generic', buffer, shape, strides, offset, 'row-major' );
* // returns <ndarray>
*
* var sh = x.shape;
* // returns [ 3, 2 ]
*
* var arr = ndarray2array( x );
* // returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ], [ 5.0, 6.0 ] ]
*
* // Define an output array:
* var y = ndzeros( [ 2, 3, 2 ], {
*     'dtype': x.dtype
* });
*
* // Create a slice:
* var s0 = null;
* var s1 = new Slice( null, null, -1 );
* var s2 = new Slice( null, null, -1 );
* var s = new MultiSlice( s0, s1, s2 );
* // returns <MultiSlice>
*
* // Perform assignment:
* var out = sliceAssign( x, y, s, false );
* // returns <ndarray>
*
* var bool = ( out === y );
* // returns true
*
* arr = ndarray2array( y );
* // returns [ [ [ 6.0, 5.0 ], [ 4.0, 3.0 ], [ 2.0, 1.0 ] ], [ [ 6.0, 5.0 ], [ 4.0, 3.0 ], [ 2.0, 1.0 ] ] ]
*/
function sliceAssign( x, y, s, strict ) {
	var view;
	var xdt;
	var ydt;

	xdt = getDType( x );
	ydt = getDType( y );

	// Safe casts are always allowed and allow same kind casts (i.e., downcasts) only when the output data type is floating-point...
	if ( !isMostlySafeCast( xdt, ydt ) ) {
		throw new TypeError( format( 'invalid argument. Input array values cannot be safely cast to the output array data type. Data types: [%s, %s].', xdt, ydt ) );
	}
	// Resolve a writable output array view:
	view = slice( y, s, strict, true );

	// Broadcast the input array:
	x = broadcast( x, getShape( view, true ) );

	// Set elements from `x` in `y`:
	assign( [ x, view ] );

	// Return the original output array:
	return y;
}
 
 
// EXPORTS //
 
module.exports = sliceAssign;