refactor: Potential fixes for 5 code quality findings in src/write.rs

[Pr0methean]

This PR applies 5/5 suggestions from code quality AI findings.

[gemini-code-assist]

Summary of Changes

Hello @Pr0methean, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request focuses on improving the overall code quality and maintainability by addressing several AI-identified findings. The changes primarily involve enhancing the clarity and completeness of documentation for key functions, strengthening safety guarantees, and refactoring a specific data serialization process to be more structured and readable. These updates aim to make the codebase easier to understand and safer to use for developers.

Highlights

• Documentation Improvements: Added comprehensive documentation to add_extra_data and add_extra_data_unchecked functions, detailing parameters, behavior, and caller responsibilities. The safety contract for set_file_metadata was also significantly enhanced.
• Code Refactoring: The update_aes_extra_data function was refactored to use a new AesExtraField struct, promoting structured serialization of AES extra data instead of manual buffer construction.
• Code Cleanup: An outdated TODO comment within the ZipWriter::copy_to_zip_writer method was removed.

Changelog

• src/write.rs
  • Added detailed parameter and behavior documentation to the add_extra_data function.
  • Introduced extensive documentation for add_extra_data_unchecked, clarifying its unchecked nature and the responsibilities of the caller.
  • Expanded the safety documentation for set_file_metadata to explicitly state assumptions and potential consequences of misuse.
  • Removed a TODO comment related to Self::finish_into_readable() in ZipWriter::copy_to_zip_writer.
  • Refactored the update_aes_extra_data function to utilize a new AesExtraField struct for structured serialization of AES extra data.

Activity

• The pull request was opened by Pr0methean.
• The changes implement 5 out of 5 suggestions from code quality AI findings.

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[amazon-q-developer]

This PR adds documentation improvements and refactors AES extra field serialization. However, there are critical compilation errors that block merge:

1. Type mismatch at line 2244: compression_method field expects an owned CompressionMethod but receives a mutable reference
2. Missing import: The AesMode type referenced in the struct definition (line 2223) is not imported, which will cause a compilation error

The documentation additions for add_extra_data, add_extra_data_unchecked, and set_file_metadata are helpful improvements. The TODO comment removals are appropriate cleanup. However, the AES extra field refactoring introduced compilation errors that must be fixed before this can be merged.

Please run cargo fmt --all and cargo clippy --all-features --all-targets as specified in the contribution guidelines, and ensure the code compiles with cargo build --all-features.

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[gemini-code-assist]

Code Review

This pull request applies several code quality improvements, primarily by adding detailed documentation to public and crate-internal functions, which greatly improves clarity and maintainability. It also includes a nice refactoring to structure the serialization of the AES extra data field. The changes are solid, and I have one minor suggestion to further improve the encapsulation in the refactored code.

[gemini-code-assist]

This is a nice refactoring! To further improve encapsulation, you could move the writing of the header ID and data size into the write_to method as well. This would make the AesExtraField struct responsible for serializing the entire extra field, not just the payload.

    // Serialize the AE-X extra field in a structured way instead of manual buffer construction.
    struct AesExtraField<'a> {
        version: AesVendorVersion,
        aes_mode: &'a AesMode,
        compression_method: CompressionMethod,
    }

    impl<'a> AesExtraField<'a> {
        const HEADER_ID: u16 = UsedExtraField::AeXEncryption as u16;
        const DATA_SIZE: u16 = 7;

        fn write_to<W: std::io::Write>(&self, mut w: W) -> std::io::Result<()> {
            // Extra field header ID.
            w.write_u16_le(Self::HEADER_ID)?;
            // Data size (fixed at 7 bytes for this field).
            w.write_u16_le(Self::DATA_SIZE)?;
            // Integer version number.
            w.write_u16_le(self.version as u16)?;
            // Vendor ID ("AE").
            w.write_all(b"AE")?;
            // AES encryption strength.
            w.write_all(&[*self.aes_mode as u8])?;
            // Real compression method.
            w.write_u16_le(self.compression_method.serialize_to_u16())?;
            Ok(())
        }
    }