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The problem with 8-bit character encoding is that it mostly needs human intelligence to interpret the correct codepage.

When you run file on a file, it can work out that the file is mostly made up of printable characters but as it's only looking at the bytes, it can't easily tell the difference between iso-8895-1 and iso-8895-2. To file, 0x80 is the same as 0x80.

file can only tell that the file is text and likely iso-8895-* or windows-*, because of the use of 0x80-0xFF. I.e. not just ASCII.

(Unicode encodings, like UTF-8, and UTF-16 are easier to detect by their byte sequence or Byte Order Mark set at the top of the file)

There are some intelligent character codepage detectors that, with the help of dictionaries from different languages, can estimate the codepage based on character/byte sequences.

The likely conversion you need is simply iso-8895-2 -> UTF-8.

What is important for you is that you know the original encoding (interpretation) and then when you validate it, that you know exactly what encoding you're viewing it.

For example, PHP will by default set the HTTP charset to iso-8895-1. That means it's quite possible for you to be converting correctly to iso-8895-2, but your browser will then "interpret" as iso-8895-1.

The best way to validate is to save the file to disk, then use a text editor like VS Code set to your required encoding beforehand before opening the file.

If you need further help, you will need to edit your question to include the exact code you're using.

Main problem is you aren't retaining a reference to your map variable.