import { protoInt64 } from '../proto-int64.js';
import { ScalarType } from '../scalar.js';

// Copyright 2021-2024 Buf Technologies, Inc.
//
// 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.
/**
 * Returns true if both scalar values are equal.
 */
function scalarEquals(type, a, b) {
    if (a === b) {
        // This correctly matches equal values except BYTES and (possibly) 64-bit integers.
        return true;
    }
    // Special case BYTES - we need to compare each byte individually
    if (type == ScalarType.BYTES) {
        if (!(a instanceof Uint8Array) || !(b instanceof Uint8Array)) {
            return false;
        }
        if (a.length !== b.length) {
            return false;
        }
        for (let i = 0; i < a.length; i++) {
            if (a[i] !== b[i]) {
                return false;
            }
        }
        return true;
    }
    // Special case 64-bit integers - we support number, string and bigint representation.
    // eslint-disable-next-line @typescript-eslint/switch-exhaustiveness-check
    switch (type) {
        case ScalarType.UINT64:
        case ScalarType.FIXED64:
        case ScalarType.INT64:
        case ScalarType.SFIXED64:
        case ScalarType.SINT64:
            // Loose comparison will match between 0n, 0 and "0".
            return a == b;
    }
    // Anything that hasn't been caught by strict comparison or special cased
    // BYTES and 64-bit integers is not equal.
    return false;
}
/**
 * Returns the zero value for the given scalar type.
 */
function scalarZeroValue(type, longType) {
    switch (type) {
        case ScalarType.BOOL:
            return false;
        case ScalarType.UINT64:
        case ScalarType.FIXED64:
        case ScalarType.INT64:
        case ScalarType.SFIXED64:
        case ScalarType.SINT64:
            // eslint-disable-next-line @typescript-eslint/no-unsafe-enum-comparison -- acceptable since it's covered by tests
            return (longType == 0 ? protoInt64.zero : "0");
        case ScalarType.DOUBLE:
        case ScalarType.FLOAT:
            return 0.0;
        case ScalarType.BYTES:
            return new Uint8Array(0);
        case ScalarType.STRING:
            return "";
        default:
            // Handles INT32, UINT32, SINT32, FIXED32, SFIXED32.
            // We do not use individual cases to save a few bytes code size.
            return 0;
    }
}
/**
 * Returns true for a zero-value. For example, an integer has the zero-value `0`,
 * a boolean is `false`, a string is `""`, and bytes is an empty Uint8Array.
 *
 * In proto3, zero-values are not written to the wire, unless the field is
 * optional or repeated.
 */
function isScalarZeroValue(type, value) {
    switch (type) {
        case ScalarType.BOOL:
            return value === false;
        case ScalarType.STRING:
            return value === "";
        case ScalarType.BYTES:
            return value instanceof Uint8Array && !value.byteLength;
        default:
            return value == 0; // Loose comparison matches 0n, 0 and "0"
    }
}

export { isScalarZeroValue, scalarEquals, scalarZeroValue };
