LCPError.swift

//
//  Copyright 2025 Readium Foundation. All rights reserved.
//  Use of this source code is governed by the BSD-style license
//  available in the top-level LICENSE file of the project.
//

import Foundation
import ReadiumShared

public enum LCPError: Error {
    /// The license could not be retrieved because the passphrase is unknown.
    case missingPassphrase

    /// The given file is not an LCP License Document (LCPL).
    case notALicenseDocument(LicenseDocumentSource)

    /// The operation can't be done right now because another License operation is running.
    case licenseIsBusy

    /// An error occured while checking the integrity of the License, it can't be retrieved.
    case licenseIntegrity(LCPClientError)

    /// The status of the License is not valid, it can't be used to decrypt the publication.
    case licenseStatus(StatusError)

    /// Can't read or write the License Document from its container.
    case licenseContainer(ContainerError)

    /// The interaction is not available with this License.
    case licenseInteractionNotAvailable

    /// This License's profile is not supported by liblcp.
    case licenseProfileNotSupported

    /// Failed to renew the loan.
    case licenseRenew(RenewError)

    /// Failed to return the loan.
    case licenseReturn(ReturnError)

    /// Failed to retrieve the Certificate Revocation List.
    case crlFetching

    /// Failed to parse information from the License or Status Documents.
    case parsing(ParsingError)

    /// A network request failed with the given error.
    case network(Error?)

    /// An unexpected LCP error occured. Please post an issue on r2-lcp-swift with the error message and how to reproduce it.
    case runtime(String)

    /// An unknown low-level error was reported.
    case unknown(Error?)
}

/// Errors while checking the status of the License, using the Status Document.
///
/// For the case (revoked, returned, cancelled, expired), app should notify the
/// user and stop there. The message to the user must be clear about the status
/// of the license: don't display "expired" if the status is "revoked". The
/// date and time corresponding to the new status should be displayed (e.g.
/// "The license expired on 01 January 2018").
///
/// If the license has been revoked, the user message should display the number
/// of devices which registered to the server. This count can be calculated
/// from the number of "register" events in the status document. If no event is
/// logged in the status document, no such message should appear (certainly not
/// "The license was registered by 0 devices").
public enum StatusError: Error {
    /// This license was cancelled on the given date.
    case cancelled(Date)
    /// This license has been returned on the given date.
    case returned(Date)
    /// This license started and expired on the given dates.
    case expired(start: Date, end: Date)
    /// This license was revoked on the given date, after being activated on
    /// `devicesCount` devices.
    case revoked(Date, devicesCount: Int)
}

/// Errors while renewing a loan.
public enum RenewError: Error {
    // Your publication could not be renewed properly.
    case renewFailed
    // Incorrect renewal period, your publication could not be renewed.
    case invalidRenewalPeriod(maxRenewDate: Date?)
    // An unexpected error has occurred on the licensing server.
    case unexpectedServerError(HTTPError)
}

/// Errors while returning a loan.
public enum ReturnError: Error {
    // Your publication could not be returned properly.
    case returnFailed
    // Your publication has already been returned before or is expired.
    case alreadyReturnedOrExpired
    // An unexpected error has occurred on the licensing server.
    case unexpectedServerError(HTTPError)
}

/// Errors while parsing the License or Status JSON Documents.
public enum ParsingError: Error {
    // The JSON is malformed and can't be parsed.
    case malformedJSON
    // The JSON is not representing a valid License Document.
    case licenseDocument
    // The JSON is not representing a valid Status Document.
    case statusDocument
    // Invalid Link.
    case link
    // Invalid Encryption.
    case encryption
    // Invalid License Document Signature.
    case signature
    // Invalid URL for link with rel %@.
    case url(rel: String)
}

/// Errors while reading or writing a LCP container (LCPL, EPUB, LCPDF, etc.)
public enum ContainerError: Error {
    // Can't access the container, it's format is wrong.
    case openFailed(Error?)
    // The file at given relative path is not found in the Container.
    case fileNotFound(String)
    // Can't read the file at given relative path in the Container.
    case readFailed(path: String)
    // Can't write the file at given relative path in the Container.
    case writeFailed(path: String)
}