/*

 * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.internal.net.http;

import java.net.URI;

import java.time.Duration;

import java.util.Optional;

import java.net.http.HttpClient;

import java.net.http.HttpRequest;

import java.net.http.HttpRequest.BodyPublisher;

import jdk.internal.net.http.common.HttpHeadersImpl;

import jdk.internal.net.http.common.Utils;

import static java.lang.String.format;

import static java.util.Objects.requireNonNull;

import static jdk.internal.net.http.common.Utils.isValidName;

import static jdk.internal.net.http.common.Utils.isValidValue;

    private HttpHeadersImpl userHeaders;

    private URI uri;

    private String method;

    private boolean expectContinue;

    private BodyPublisher bodyPublisher;

    private volatile Optional<HttpClient.Version> version;

    private Duration duration;

    public HttpRequestBuilderImpl(URI uri) {

        requireNonNull(uri, "uri must be non-null");

        checkURI(uri);

        this.uri = uri;

        this.userHeaders = new HttpHeadersImpl();

        this.method = "GET"; // default, as per spec

        this.version = Optional.empty();

    }

    public HttpRequestBuilderImpl() {

        this.userHeaders = new HttpHeadersImpl();

        this.method = "GET"; // default, as per spec

        this.version = Optional.empty();

    }

    @Override

    public HttpRequestBuilderImpl uri(URI uri) {

        requireNonNull(uri, "uri must be non-null");

        checkURI(uri);

        this.uri = uri;

        return this;

    }

    private static IllegalArgumentException newIAE(String message, Object... args) {

        return new IllegalArgumentException(format(message, args));

    }

    private static void checkURI(URI uri) {

        String scheme = uri.getScheme();

        if (scheme == null)

            throw newIAE("URI with undefined scheme");

        scheme = scheme.toLowerCase();

        if (!(scheme.equals("https") || scheme.equals("http"))) {

            throw newIAE("invalid URI scheme %s", scheme);

        }

        if (uri.getHost() == null) {

            throw newIAE("unsupported URI %s", uri);

        }

    }

    @Override

    public HttpRequestBuilderImpl copy() {

        HttpRequestBuilderImpl b = new HttpRequestBuilderImpl(this.uri);

        b.userHeaders = this.userHeaders.deepCopy();

        b.method = this.method;

        b.expectContinue = this.expectContinue;

        b.bodyPublisher = bodyPublisher;

        b.uri = uri;

        b.duration = duration;

        b.version = version;

        return b;

    }

    private void checkNameAndValue(String name, String value) {

        requireNonNull(name, "name");

        requireNonNull(value, "value");

        if (!isValidName(name)) {

            throw newIAE("invalid header name: \"%s\"", name);

        }

        if (!Utils.ALLOWED_HEADERS.test(name)) {

            throw newIAE("restricted header name: \"%s\"", name);

        }

        if (!isValidValue(value)) {

            throw newIAE("invalid header value: \"%s\"", value);

        }

    }

    @Override

    public HttpRequestBuilderImpl setHeader(String name, String value) {

        checkNameAndValue(name, value);

        userHeaders.setHeader(name, value);

        return this;

    }

    @Override

    public HttpRequestBuilderImpl header(String name, String value) {

        checkNameAndValue(name, value);

        userHeaders.addHeader(name, value);

        return this;

    }

    @Override

    public HttpRequestBuilderImpl headers(String... params) {

        requireNonNull(params);

        if (params.length == 0 || params.length % 2 != 0) {

            throw newIAE("wrong number, %d, of parameters", params.length);

        }

        for (int i = 0; i < params.length; i += 2) {

            String name  = params[i];

            String value = params[i + 1];

            header(name, value);

        }

        return this;

    }

    @Override

    public HttpRequestBuilderImpl expectContinue(boolean enable) {

        expectContinue = enable;

        return this;

    }

    @Override

    public HttpRequestBuilderImpl version(HttpClient.Version version) {

        requireNonNull(version);

        this.version = Optional.of(version);

        return this;

    }

    HttpHeadersImpl headers() {  return userHeaders; }

    URI uri() { return uri; }

    String method() { return method; }

    boolean expectContinue() { return expectContinue; }

    BodyPublisher bodyPublisher() { return bodyPublisher; }

    Optional<HttpClient.Version> version() { return version; }

    @Override

    public HttpRequest.Builder GET() {

        return method0("GET", null);

    }

    @Override

    public HttpRequest.Builder POST(BodyPublisher body) {

        return method0("POST", requireNonNull(body));

    }

    @Override

    public HttpRequest.Builder DELETE(BodyPublisher body) {

        return method0("DELETE", requireNonNull(body));

    }

    @Override

    public HttpRequest.Builder PUT(BodyPublisher body) {

        return method0("PUT", requireNonNull(body));

    }

    @Override

    public HttpRequest.Builder method(String method, BodyPublisher body) {

        requireNonNull(method);

        if (method.equals(""))

            throw newIAE("illegal method <empty string>");

        if (method.equals("CONNECT"))

            throw newIAE("method CONNECT is not supported");

        return method0(method, requireNonNull(body));

    }

    private HttpRequest.Builder method0(String method, BodyPublisher body) {

        assert method != null;

        assert !method.equals("GET") ? body != null : true;

        assert !method.equals("");

        this.method = method;

        this.bodyPublisher = body;

        return this;

    }

    @Override

    public HttpRequest build() {

        if (uri == null)

            throw new IllegalStateException("uri is null");

        assert method != null;

        return new HttpRequestImpl(this);

    }

    @Override

    public HttpRequest.Builder timeout(Duration duration) {

        requireNonNull(duration);

        if (duration.isNegative() || Duration.ZERO.equals(duration))

            throw new IllegalArgumentException("Invalid duration: " + duration);

        this.duration = duration;

        return this;

    }

    Duration timeout() { return duration; }

}