Convert QP Encoded Text to Plain Text Decode Quoted-Printable encoded text back to readable form.

The qpDecode function works by using the replace method of JavaScript strings to eliminate soft line breaks, which are represented by = followed by a newline character (\r?\n), and replacing them with an empty string. This is done in two steps: first, all occurrences of =\r?\n are removed, ensuring that the decoded text does not contain any unnecessary line breaks. Then, it uses another regular expression to find all =HH sequences, where H represents a hexadecimal digit, and replaces each sequence with its corresponding ASCII character using String.fromCharCode. The parseInt function is used with base 16 to convert the two-character hex code into a decimal value that can be passed to String.fromCharCode.

The React useCallback hook is used to memoize the onProcess function, which wraps the qpDecode function and provides basic error handling by catching any exceptions that occur during decoding and returning an error message. This ensures that the tool remains responsive even when faced with invalid input. The TextToolLayout component from the @/components/shared directory is used to render the user interface, providing input fields for the quoted-printable string and a button to trigger the decoding process. When the onProcess function is called, it attempts to decode the input string using qpDecode and displays the result in the output field.

In terms of data formats, the tool assumes that the input string is encoded in Quoted-Printable format as defined by RFC 2045, which uses =HH sequences to represent non-ASCII characters. The decoded text is then interpreted as UTF-8, allowing for correct representation of multi-byte characters. The use of client-side JavaScript and React allows the tool to operate entirely within the browser, eliminating the need for server-side processing or external libraries like Node.js modules. This approach enables fast and efficient decoding of quoted-printable strings without incurring additional overhead.