//
//  APIRequest.swift
//  suixinkan
//

import Foundation

/// HTTP 方法实体，限制网络层支持的请求方法。
enum HTTPMethod: String {
    case get = "GET"
    case post = "POST"
    case put = "PUT"
    case delete = "DELETE"
}

/// 强类型 API 请求实体，描述一次请求的方法、路径、参数、Header 和响应类型。
nonisolated struct APIRequest<Response: Decodable> {
    var method: HTTPMethod
    var path: String
    var queryItems: [URLQueryItem]
    var headers: [String: String]
    var body: AnyEncodable?

    /// 创建一个 API 请求，并把可编码请求体擦除为统一的 AnyEncodable。
    init<Body: Encodable>(
        method: HTTPMethod,
        path: String,
        queryItems: [URLQueryItem] = [],
        headers: [String: String] = [:],
        body: Body? = Optional<EmptyPayload>.none
    ) {
        self.method = method
        self.path = path
        self.queryItems = queryItems
        self.headers = headers
        self.body = body.map(AnyEncodable.init)
    }
}

/// Encodable 类型擦除包装器，用于在 APIRequest 中保存任意请求体。
nonisolated struct AnyEncodable: Encodable, Sendable {
    private let encodeValue: @Sendable (Encoder) throws -> Void

    init<Value: Encodable>(_ value: Value) {
        encodeValue = { encoder in
            try value.encode(to: encoder)
        }
    }

    func encode(to encoder: Encoder) throws {
        try encodeValue(encoder)
    }
}