import Foundation

enum APIError: LocalizedError, Equatable {
    case invalidURL
    case invalidResponse
    case httpStatus(Int, String?)
    case decoding(String)
    case unauthorized
    case notFound
    case mergeConflict

    var errorDescription: String? {
        switch self {
        case .invalidURL:
            return "The instance URL is invalid."
        case .invalidResponse:
            return "The server returned an invalid response."
        case .httpStatus(let code, let message):
            if code == 401 || code == 403 {
                return "Authentication failed. Check your token."
            }
            if code == 409 {
                return "This branch is out of date or conflicts with the base branch. Update the branch and try again."
            }
            return message?.isEmpty == false
                ? "Server error (\(code)): \(message!)"
                : "Server error (\(code))."
        case .decoding(let detail):
            return "Could not parse the server response: \(detail)"
        case .unauthorized:
            return "Authentication failed. Check your token."
        case .notFound:
            return "Not found."
        case .mergeConflict:
            return "This branch is out of date or conflicts with the base branch. Update the branch and try again."
        }
    }
}