opsys

type OS interface {
	afero.Fs
	// FileAccess checks if the binary has access to the given file path.
	FileAccess(fp string) error
	// FileExist checks if the given path already exists.
	FileExist(fp string) (bool, error)
	// GetMacOSVersion checks the version of the current operating system,
	// assuming it is Mac OS.
	GetMacOSVersion() (*semver.Version, error)
	// GetContactMap gets a map of vcards indexed by phone numbers and email
	// addresses specified in those cards, from the vcard file at the given
	// path.
	GetContactMap(path string) (map[string]*vcard.Card, error)
	// ReadFile is a thin wrapper on the afero ReadFile utility.
	ReadFile(fp string) (string, error)
	// CopyFile copies the src file to the dstDir directory. If the file is
	// designated as unique and it already exists in the destination directory,
	// a numbered suffix will be added to the copied file name. The path of the
	// copied file is returned.
	CopyFile(src, dstDir string, unique bool) (string, error)
	// RmTempDir removes the temporary directory used by this package for
	// staging converted images for inclusion in PDF files.
	RmTempDir() error
	// GetOpenFilesLimit gets the current limit on the number of open files.
	GetOpenFilesLimit() int
	// SetOpenFilesLimit sets the open files limit to the given value to
	// accommodate wkhtmltopdf:
	// https://github.com/wkhtmltopdf/wkhtmltopdf/issues/3081#issue-172083214
	SetOpenFilesLimit(n int) error
	// HEIC2JPG converts the src file to a JPEG image if the src file is an
	// HEIC image, returning the path to the JPEG image. Otherwise the src
	// path is returned.
	HEIC2JPG(src string) (string, error)
	NewTxtOutFile(afero.File) OutFile
	NewPDFOutFile(chatFile afero.File, pdfg pdfgen.PDFGenerator, includePPA bool) OutFile
}

type OutFile interface {
	// Name returns the filepath of the Outfile.
	Name() string
	// WriteMessage adds the given message to the Outfile.
	WriteMessage(msg string) error
	// WriteAttachment embeds the given attachment in the Outfile, or adds a
	// reference to it if embedding is not possible (e.g. if the Outfile is
	// plain text, or the attachment is a movie). The return value lets the
	// caller know whether the file was embedded or not.
	WriteAttachment(attPath string) (bool, error)
	// ReferenceAttachment adds a reference to the given filename in the Outfile.
	ReferenceAttachment(filename string) error
	// Flush flushes the contents of an OutFile to disk, and returns the
	// number of images embedded in the OutFile.
	Flush() (int, error)
}