import CryptoKit
import Foundation

struct AgentOutboxRow: Codable, Equatable, Sendable {
    var requestID: String
    var content: String
    var createdAt: Date
    var status: String = "sending"
    var seenOnServer = false
    var confirmed = false
    var error: String?
    var attachments: [AgentAttachment]? = nil // Optional for legacy text-only outboxes.
    var draftID: String? = nil // Recovers a crash between outbox persistence and clearing the composer.
    var id: String { "inbound:sybil:\(requestID)" }
    var message: Message {
        var info: [String: JSONValue] = ["kind": .string("message"), "status": .string(status), "requestId": .string(requestID)]
        if let error { info["error"] = .string(error) }
        if let attachments, !attachments.isEmpty { info["agentAttachments"] = .array(attachments.map(\.metadataValue)) }
        return Message(id: id, createdAt: createdAt, role: .user, content: content, metadata: .object(info))
    }
}

struct AgentOutboxStorage: Sendable {
    var read: @Sendable () throws -> [AgentOutboxRow]
    var write: @Sendable ([AgentOutboxRow]) throws -> Void

    static func file(baseURL: URL) -> Self {
        // Separate installations, but never persist tokens in a filename or payload.
        let key = SHA256.hash(data: Data(baseURL.absoluteString.utf8)).map { String(format: "%02x", $0) }.joined()
        let directory = URL.applicationSupportDirectory.appendingPathComponent("AgentOutbox", isDirectory: true)
        let url = directory.appendingPathComponent("\(key).json")
        return Self(read: {
            guard FileManager.default.fileExists(atPath: url.path) else { return [] }
            return try JSONDecoder().decode([AgentOutboxRow].self, from: Data(contentsOf: url))
        }, write: { rows in
            let data = try JSONEncoder().encode(rows)
            guard rows.count <= 100, data.count <= 2 * 1024 * 1024 else {
                throw AgentFailure(message: "Retry pending messages before sending more.")
            }
            try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true)
            try data.write(to: url, options: [.atomic, .completeFileProtectionUntilFirstUserAuthentication])
        })
    }
}