db

type Bundle struct {
	// VFilePart is the storage file (=one bundle)
	VFilePart // extension

	// Content is the list of VirtFile (string: VFiles map key) in this bundle.
	Content []string
}

type Db struct {

	// VFiles contains all virtual files.
	// The map key is the RelPath (@see VirtFile.Id).
	VFiles map[string]VirtFile

	// Bundles is OPTIONAL and bundles some small virtual files together.
	// The map key is the StorageName of the bundle file (@see VFilePart.Id).
	Bundles map[string]Bundle
}

type FolderEl struct {

	// RelPath is the path of the file with the mount folder as root.
	// Example: foo/bar/test.txt
	RelPath string

	// IsDir marks this element as a folder.
	IsDir bool
}

type VFilePart struct {

	// PlainSHA512 is the SHA512 hash of the virtual file part content (plain text).
	// This is needed for the data encryption key and the encrypted file name.
	// Example: 64 bytes (SHA512)
	PlainSHA512 []byte

	// StorageName of the storage file name. The name is not unique and there can be multiple files with the same name.
	// Example: f233e8122942b4dd068237ed73b123092c7e59964626f7ae842a94ad3c4cc7a9791698fa080d0d4382dea1c6a3cb6d30
	StorageName string

	// StorageSize is the storage file size in bytes.
	// Example 16317
	StorageSize int64

	// StorageMd5 is the hash of the storage file content (hex string).
	// Example: 098f6bcd4621d373c0de4e832627b4f6
	StorageMd5 string

	// CryptDataKey is the key for encrypting and decrypting data.
	// The key is derived from the unencrypted original content (PlainSHA512).
	// Example: 32 bytes (AES256 key)
	CryptDataKey []byte
}

type VirtFile struct {

	// RelPath is the path of the file with the mount folder as root.
	// Example: foo/bar/test.txt
	RelPath string

	// FileSize is the file size in bytes. (real local file)
	// Example 16317
	FileSize int64

	// MTime show the last change or update of the object (unix time; seconds).
	// If a file has never been changed, it's the time of creation.
	// Example: 1584535538
	MTime int64

	// IsDir marks this element as a folder.
	IsDir bool

	// FolderContent (IF FOLDER) is the list of folder sub elements.
	// Only IsDir and RelPath are set for a folder sub element.
	FolderContent []FolderEl

	// Parts (IF FILE) is the list of parts that make up the virtual file.
	// If the file size is 0, there are no parts.
	Parts []VFilePart

	// UseCompression (IF FILE) determines whether the data is compressed or not.
	// Only very small files with one part can be compressed (@see MaxFileSizeForCompression).
	// In this case, FileSize and StorageSize are different.
	// Example: true
	UseCompression bool

	// AlsoInBundle (IF FILE; OPTIONAL) is the bundle ID (@see Db.Bundles).
	// Only very small files with one part can be bundled (@see MaxFileSizeToBundle).
	AlsoInBundle string
}