builder-pattern.swift

builder-pattern.swift

final class URLRequestBuilder {
    private var components = URLComponents()
    private var httpMethod: String = "GET"
    private var headers: [String: String] = [:]
    private var body: [String: Any]?

    // MARK: - Lifecycle
    
    init(baseUrl: String = "https://api.themoviedb.org") {
        components = URLComponents(string: baseUrl)!
    }

    // MARK: - Construction Classes
    
    func setPath(_ path: String) -> URLRequestBuilder {
        var path = path
        if !path.hasPrefix("/") {
            path = "/" + path
        }
        components.path = path
        return self
    }

    func setQueryItems(_ queryItems: [String: String]) -> URLRequestBuilder {
        components.queryItems = queryItems.map { key, value in
            URLQueryItem(name: key, value: "\(value)")
        }
        components.percentEncodedQuery = components.percentEncodedQuery?.replacingOccurrences(of: "+", with: "%2B")
        return self
    }

    func setHTTPMethod(_ method: String) -> URLRequestBuilder {
        httpMethod = method
        return self
    }

    func setHeaders(_ headers: [String: String]) -> URLRequestBuilder {
        self.headers = headers
        return self
    }

    func setBody(_ body: [String: Any]) -> URLRequestBuilder {
        self.body = body
        return self
    }

    // MARK: - Builder Pattern
    
    func build() -> URLRequest? {
        guard let url = components.url else { return nil }

        var request = URLRequest(url: url)
        request.httpMethod = httpMethod
        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        request.setValue("application/json", forHTTPHeaderField: "Accept")
        headers.forEach { request.addValue($0.value, forHTTPHeaderField: $0.key) }

        if let body = body {
            let jsonData = try? JSONSerialization.data(withJSONObject: body, options: [])
            request.httpBody = jsonData
        }

        return request
    }
}