package license.sdk;

import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

public final class LicenseClient {
    public static final class ApiResponse {
        private final int statusCode;
        private final String body;

        private ApiResponse(int statusCode, String body) {
            this.statusCode = statusCode;
            this.body = body;
        }

        public int statusCode() { return statusCode; }
        public String body() { return body; }
    }

    private final HttpClient http = HttpClient.newHttpClient();
    private final String baseUrl;
    private final String machineCode;
    private final String appKey;

    public LicenseClient(String baseUrl, String machineCode) {
        this(baseUrl, machineCode, "");
    }

    /** @param appKey 软件接入密钥（管理后台「软件管理」生成），为空表示不携带 */
    public LicenseClient(String baseUrl, String machineCode, String appKey) {
        this.baseUrl = baseUrl.replaceAll("/$", "");
        this.machineCode = machineCode.trim().toUpperCase();
        this.appKey = appKey == null ? "" : appKey.trim();
    }

    public String login(String cardKey, String deviceName) throws IOException, InterruptedException {
        return loginResponse(cardKey, deviceName).body();
    }

    public String heartbeat(String cardKey) throws IOException, InterruptedException { return heartbeatResponse(cardKey).body(); }
    public String listDevices(String cardKey) throws IOException, InterruptedException { return listDevicesResponse(cardKey).body(); }
    public String unbind(String cardKey) throws IOException, InterruptedException { return unbindResponse(cardKey).body(); }

    public ApiResponse loginResponse(String cardKey, String deviceName) throws IOException, InterruptedException {
        StringBuilder sb = new StringBuilder(160);
        sb.append("{\"cardKey\":\"").append(escape(cardKey)).append("\",\"machineCode\":\"").append(machineCode)
          .append("\",\"deviceName\":\"").append(escape(deviceName == null ? "" : deviceName)).append('"');
        if (!appKey.isEmpty()) sb.append(",\"appKey\":\"").append(escape(appKey)).append('"');
        sb.append('}');
        return post("/api/card/verify", sb.toString());
    }

    public ApiResponse heartbeatResponse(String cardKey) throws IOException, InterruptedException { return post("/api/card/heartbeat", request(cardKey)); }
    public ApiResponse listDevicesResponse(String cardKey) throws IOException, InterruptedException { return post("/api/card/devices", request(cardKey)); }
    public ApiResponse unbindResponse(String cardKey) throws IOException, InterruptedException { return post("/api/card/unbind", request(cardKey)); }

    private String request(String cardKey) {
        StringBuilder sb = new StringBuilder(128);
        sb.append("{\"cardKey\":\"").append(escape(cardKey)).append("\",\"machineCode\":\"").append(machineCode).append('"');
        if (!appKey.isEmpty()) sb.append(",\"appKey\":\"").append(escape(appKey)).append('"');
        sb.append('}');
        return sb.toString();
    }
    private ApiResponse post(String path, String body) throws IOException, InterruptedException {
        HttpRequest request = HttpRequest.newBuilder(URI.create(baseUrl + path)).header("Content-Type", "application/json").POST(HttpRequest.BodyPublishers.ofString(body)).build();
        HttpResponse<String> response = http.send(request, HttpResponse.BodyHandlers.ofString());
        return new ApiResponse(response.statusCode(), response.body());
    }
    private String escape(String value) { return value == null ? "" : value.replace("\\", "\\\\").replace("\"", "\\\""); }
}