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import path from 'node:path';
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export const forbiddenRegExp = path.sep === '/' ? /[/\x00]/ : /[/\x00\\]/;
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/**
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 * Checks if an object has a toString method.
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 * @param {object} o Object to check
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 * @returns {boolean} True if the object has a toString method, false otherwise
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 */
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function hasToString(o) {
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    return o != null && typeof o.toString === 'function';
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}
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/**
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 * Gets a middleware function that validates the field in the request body.
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 * @param {string} fieldName Field name
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 * @returns {import('express').RequestHandler} Middleware function
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 */
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export function getFileNameValidationFunction(fieldName) {
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    /**
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    * Validates the field in the request body.
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    * @param {import('express').Request} req Request object
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    * @param {import('express').Response} res Response object
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    * @param {import('express').NextFunction} next Next middleware
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    */
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    return function validateAvatarUrlMiddleware(req, res, next) {
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        if (req.body && fieldName in req.body && (typeof req.body[fieldName] === 'string' || hasToString(req.body[fieldName]))) {
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            if (forbiddenRegExp.test(req.body[fieldName])) {
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                console.error('An error occurred while validating the request body', {
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                    handle: req.user.profile.handle,
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                    path: req.originalUrl,
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                    field: fieldName,
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                    value: req.body[fieldName],
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                });
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                return res.sendStatus(400);
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            }
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        }
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        next();
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    };
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}
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const avatarUrlValidationFunction = getFileNameValidationFunction('avatar_url');
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export default avatarUrlValidationFunction;