Changes in version 0.2.1 (2024-03-29)                  

New features

  - get_bookmarks_pdftools() gets pdf bookmark information using
    pdftools::pdf_toc() (#30). Note though due to poppler library
    limitations it can't return page numbers that correspond to each
    bookmark. Hence get_bookmarks() will try to use the following helper
    functions in the following order:
    
    1.  get_bookmarks_pdftk()
    2.  get_bookmarks_pdftools()

Bug fixes and minor improvements

  - We can again disable old bookmarks when setting new bookmarks in
    set_bookmarks_gs() for the newest versions of ghostscript (#59). The
    new approach means we could remove some GPLv3 code and have
    relicensed the package under the MIT license.
  - Improved support for reading/writing Unicode values in non-Unicode
    locales (#57).
  - get_bookmarks() and get_bookmarks_pdftk() no longer returns its data
    frame value invisibly.

                 Changes in version 0.1.4 (2023-10-02)                  

  - Unit tests have been adjusted to prevent a CRAN R CMD check ERROR on
    an M1 Mac machine running macOS 14 (#58).

                 Changes in version 0.1.3 (2023-02-26)                  

Bug fixes and minor improvements

  - set_docinfo_exiftool() should now losslessly write all legal
    datetimes (#55). set_docinfo()'s priority order has been updated to
    the following:
    
    1.  set_docinfo_exiftool()
    2.  set_docinfo_gs()
    3.  set_docinfo_pdftk()

  - Unit tests have been adjusted to prevent CRAN R CMD check ERRORs on
    certain CRAN platforms that don't have ghostscript installed or are
    ran in a non-Unicode locale (#56).

                 Changes in version 0.1.1 (2023-02-22)                  

Initial features

  - cat_bookmarks() concatenates a list of bookmarks into a single
    bookmarks data frame while updating the page numbers. Useful if
    wanting to concatenate multiple pdf files together and would like to
    preserve the bookmarks information.

  - get_bookmarks() returns a data frame with pdf bookmarks information.
    get_bookmarks() will try to use the following helper functions in
    the following order:
    
    1.  get_bookmarks_pdftk() which wraps pdftk command-line tool

  - set_bookmarks() sets (replaces) pdf bookmarks information.
    set_bookmarks() will try to use the following helper functions in
    the following order:
    
    1.  set_bookmarks_gs() which wraps ghostscript command-line tool
    2.  set_bookmarks_pdftk() which wraps pdftk command-line tool

  - docinfo() provides an {R6} object to represent pdf documentation
    info entries.

  - as_docinfo() can coerce objects into docinfo() objects. In
    particular there is an as_docinfo.xmp() method to coerce xmp()
    objects.

  - get_docinfo() reads in pdf documentation info entries from pdf
    file(s). get_docinfo() will try to use the following helper
    functions in the following order:
    
    1.  get_docinfo_pdftk() which wraps pdftk command-line tool
    2.  get_docinfo_exiftool() which wraps exiftool command-line tool
    3.  get_docinfo_pdftools() which wraps pdftools::pdf_info()

  - set_docinfo() sets pdf documentation info entries to a pdf file.
    set_docinfo() will try to use the following helper functions in the
    following order:
    
    1.  set_docinfo_gs() which wraps ghostscript command-line tool
    2.  set_docinfo_pdftk() which wraps pdftk command-line tool
    3.  set_docinfo_exiftool() which wraps exiftool command-line tool

  - xmp() provides an {R6} object to represent xmp metadata.
    
      - as_lang_alt() supports "language alternative" XMP tags.

  - as_xmp() can coerce objects into xmp() objects. In particular there
    is an as_xmp.docinfo() method to coerce docinfo() objects.

  - get_xmp() reads in xmp metadata from media file(s). get_xmp() will
    try to use the following helper functions in the following order:
    
    1.  get_xmp_exiftool() which wraps exiftool command-line tool

  - set_xmp() sets xmp metadata in media file(s). set_xmp() will try to
    use the following helper functions in the following order:
    
    1.  set_xmp_exiftool() which wraps exiftool command-line tool

  - cat_pages() concatenates (pdf) file(s) into a single output pdf.
    cat_pages() will try to use the following helper functions in the
    following order:
    
    1.  cat_pages_qpdf() which wraps qpdf::pdf_combine()
    2.  cat_pages_pdftk() which wraps pdftk command-line tool
    3.  cat_pages_gs() which wraps ghostscript command-line tool

  - n_pages() returns the number of pages in the (pdf) file(s).
    n_pages() will try to use the following helper functions in the
    following order:
    
    1.  n_pages_qpdf() which wraps qpdf::pdf_length()
    2.  n_pages_exiftool() which wraps exiftool command-line tool
    3.  n_pages_pdftk() which wraps pdftk command-line tool
    4.  n_pages_gs() which wraps ghostscript command-line tool

  - The following functions detect support for various higher-level
    features:
    
      - supports_get_bookmarks()
      - supports_set_bookmarks()
      - supports_get_docinfo()
      - supports_set_docinfo()
      - supports_get_xmp()
      - supports_set_xmp()
      - supports_n_pages()

  - The following functions detect support for various command-line
    tools needed for some lower-level helper functions:
    
      - supports_exiftool() detects support for exiftool
      - supports_gs() detects support for ghostscript
      - supports_pdftk() detects support for pdftk

  - enable_feature_message() returns a character vector with the
    information needed to install the requested feature. Formatted for
    use with rlang::abort(), rlang::warn(), or rlang::inform().

  - The spdx_licenses data set contains the SPDX License List.