//===----------------------------------------------------------------------===//
// Copyright © 2026 Apple Inc. and the container project authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//   https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//===----------------------------------------------------------------------===//

import ContainerPersistence
import ContainerResource
import ContainerXPC
import ContainerizationError
import Foundation
import MachineAPIClient

public struct MachinesHarness: Sendable {
    let service: MachinesService

    public init(service: MachinesService) {
        self.service = service
    }

    @Sendable
    public func create(_ message: XPCMessage) async throws -> XPCMessage {
        let machineConfig = message.dataNoCopy(key: MachineKeys.machineConfig.rawValue)
        guard let machineConfig else {
            throw ContainerizationError(
                .invalidArgument,
                message: "container machine configuration cannot be empty"
            )
        }

        let machineResources = message.dataNoCopy(key: MachineKeys.machineResources.rawValue)
        var resources: MachineResources? = nil
        if let machineResources {
            resources = try JSONDecoder().decode(MachineResources.self, from: machineResources)
        }

        let bootConfigData = message.dataNoCopy(key: MachineKeys.bootConfig.rawValue)
        guard let bootConfigData else {
            throw ContainerizationError(.invalidArgument, message: "bootConfig cannot be empty")
        }
        let bootConfig = try JSONDecoder().decode(MachineConfig.self, from: bootConfigData)

        let config = try JSONDecoder().decode(MachineConfiguration.self, from: machineConfig)

        try await service.create(configuration: config, resources: resources, bootConfig: bootConfig)
        return message.reply()
    }

    @Sendable
    public func delete(_ message: XPCMessage) async throws -> XPCMessage {
        let id = message.string(key: MachineKeys.id.rawValue)
        guard let id else {
            throw ContainerizationError(.invalidArgument, message: "id cannot be empty")
        }
        try await service.delete(id: id)
        return message.reply()
    }

    @Sendable
    public func list(_ message: XPCMessage) async throws -> XPCMessage {
        let machines = try await service.list()
        let data = try JSONEncoder().encode(machines)

        let reply = message.reply()
        reply.set(key: MachineKeys.machines.rawValue, value: data)
        return reply
    }

    @Sendable
    public func getDefault(_ message: XPCMessage) async throws -> XPCMessage {
        let id = try await service.getDefault()

        let reply = message.reply()
        if let id {
            reply.set(key: MachineKeys.id.rawValue, value: id)
        }
        return reply
    }

    @Sendable
    public func setDefault(_ message: XPCMessage) async throws -> XPCMessage {
        let id = message.string(key: MachineKeys.id.rawValue)
        guard let id else {
            throw ContainerizationError(.invalidArgument, message: "id cannot be empty")
        }
        try await service.setDefault(id: id)

        return message.reply()
    }

    @Sendable
    public func boot(_ message: XPCMessage) async throws -> XPCMessage {
        let id = message.string(key: MachineKeys.id.rawValue)

        var dynamicEnv: [String: String] = [:]
        if let dynamicEnvData = message.dataNoCopy(key: MachineKeys.dynamicEnv.rawValue) {
            dynamicEnv = try JSONDecoder().decode([String: String].self, from: dynamicEnvData)
        }

        let snapshot = try await service.boot(id: id, dynamicEnv: dynamicEnv)
        let data = try JSONEncoder().encode(snapshot)

        let reply = message.reply()
        reply.set(key: MachineKeys.snapshot.rawValue, value: data)
        return reply
    }

    @Sendable
    public func stop(_ message: XPCMessage) async throws -> XPCMessage {
        let id = message.string(key: MachineKeys.id.rawValue)
        guard let id else {
            throw ContainerizationError(.invalidArgument, message: "id cannot be empty")
        }
        try await service.stop(id: id)
        return message.reply()
    }

    @Sendable
    public func inspect(_ message: XPCMessage) async throws -> XPCMessage {
        let id = message.string(key: MachineKeys.id.rawValue)
        guard let id else {
            throw ContainerizationError(.invalidArgument, message: "id cannot be empty")
        }
        let snapshot = try await service.inspect(id: id)
        let data = try JSONEncoder().encode(snapshot)

        let reply = message.reply()
        reply.set(key: MachineKeys.snapshot.rawValue, value: data)
        return reply
    }

    @Sendable
    public func setConfig(_ message: XPCMessage) async throws -> XPCMessage {
        let id = message.string(key: MachineKeys.id.rawValue)
        guard let id else {
            throw ContainerizationError(.invalidArgument, message: "id cannot be empty")
        }
        let bootConfigData = message.dataNoCopy(key: MachineKeys.bootConfig.rawValue)
        guard let bootConfigData else {
            throw ContainerizationError(.invalidArgument, message: "boot config cannot be empty")
        }
        let bootConfig = try JSONDecoder().decode(MachineConfig.self, from: bootConfigData)
        try await service.setConfig(id: id, bootConfig: bootConfig)
        return message.reply()
    }

    @Sendable
    public func logs(_ message: XPCMessage) async throws -> XPCMessage {
        let id = message.string(key: MachineKeys.id.rawValue)
        guard let id else {
            throw ContainerizationError(.invalidArgument, message: "id cannot be empty")
        }

        let fds = try await service.logs(id: id)
        let reply = message.reply()
        try reply.set(key: MachineKeys.logs.rawValue, value: fds)
        return reply
    }
}