// This source code is dual-licensed under the Mozilla Public License ("MPL"),
// version 1.1 and the Apache License ("ASL"), version 2.0.
//
// The ASL v2.0:
//
// ---------------------------------------------------------------------------
// Copyright 2016 Pivotal Software, Inc.
//
// 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
//
//    http://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.
// ---------------------------------------------------------------------------
//
// The MPL v1.1:
//
// ---------------------------------------------------------------------------
// The contents of this file are subject to the Mozilla Public License
// Version 1.1 (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.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS"
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
// License for the specific language governing rights and limitations
// under the License.
//
// The Original Code is RabbitMQ
//
// The Initial Developer of the Original Code is Pivotal Software, Inc.
// All Rights Reserved.
//
// Alternatively, the contents of this file may be used under the terms
// of the Apache Standard license (the "ASL License"), in which case the
// provisions of the ASL License are applicable instead of those
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// under the terms of the ASL License and not to allow others to use
// your version of this file under the MPL, indicate your decision by
// deleting the provisions above and replace them with the notice and
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// under either the MPL or the ASL License.
// ---------------------------------------------------------------------------

#import "RMQHandshaker.h"

@interface RMQHandshaker ()
@property (nonatomic, weak) id<RMQSender> sender;
@property (nonatomic, weak) RMQConnectionConfig *config;
@property (nonatomic, copy) void (^completionHandler)(NSNumber *heartbeatTimeout);
@property (nonatomic, strong) NSNumber *heartbeatTimeout;
@end

@implementation RMQHandshaker

- (instancetype)initWithSender:(id<RMQSender>)sender
                        config:(RMQConnectionConfig *)config
             completionHandler:(void (^)(NSNumber *heartbeatTimeout))completionHandler {
    self = [super init];
    if (self) {
        self.sender = sender;
        self.config = config;
        self.completionHandler = completionHandler;
        self.heartbeatTimeout = @0;
    }
    return self;
}

- (void)handleFrameset:(RMQFrameset *)frameset {
    id method = frameset.method;
    if ([method isKindOfClass:[RMQConnectionStart class]]) {
        [self sendMethod:self.startOk channelNumber:frameset.channelNumber];
        [self.reader run];
    } else if ([method isKindOfClass:[RMQConnectionTune class]]) {
        RMQConnectionTuneOk *tuneOk = [self tuneOkForTune:method];
        self.heartbeatTimeout = @(tuneOk.heartbeat.integerValue);

        [self sendMethod:tuneOk channelNumber:frameset.channelNumber];
        [self sendMethod:self.connectionOpen channelNumber:frameset.channelNumber];
        [self.reader run];
    } else {
        self.completionHandler(self.heartbeatTimeout);
    }
}

#pragma mark - Private

- (RMQConnectionStartOk *)startOk {
    RMQBoolean *yes = [[RMQBoolean alloc] init:YES];
    RMQTable *capabilities = [[RMQTable alloc] init:@{@"publisher_confirms"           : yes,
                                                      @"consumer_cancel_notify"       : yes,
                                                      @"exchange_exchange_bindings"   : yes,
                                                      @"basic.nack"                   : yes,
                                                      @"connection.blocked"           : yes,
                                                      @"authentication_failure_close" : yes}];

    NSBundle *bundle = [NSBundle bundleWithIdentifier:@"io.pivotal.RMQClient"];
    NSString *version = bundle.infoDictionary[@"CFBundleShortVersionString"];

    RMQTable *clientProperties = [[RMQTable alloc] init:
                                  @{@"capabilities" : capabilities,
                                    @"product"      : [[RMQLongstr alloc] init:@"RMQClient"],
                                    @"platform"     : [[RMQLongstr alloc] init:@"iOS"],
                                    @"version"      : [[RMQLongstr alloc] init:version],
                                    @"information"  : [[RMQLongstr alloc] init:@"https://github.com/rabbitmq/rabbitmq-objc-client"]}];

    return [[RMQConnectionStartOk alloc] initWithClientProperties:clientProperties
                                                        mechanism:[[RMQShortstr alloc] init:self.config.authMechanism]
                                                         response:self.config.credentials
                                                           locale:[[RMQShortstr alloc] init:@"en_GB"]];
}

- (RMQConnectionTuneOk *)tuneOkForTune:(RMQConnectionTune *)tune {
    RMQConnectionConfig *client = self.config;
    RMQConnectionTune *server = tune;

    NSNumber *channelMax = [self negotiateBetweenClientValue:client.channelMax
                                                 serverValue:@(server.channelMax.integerValue)];
    NSNumber *frameMax   = [self negotiateBetweenClientValue:client.frameMax
                                                 serverValue:@(server.frameMax.integerValue)];
    NSNumber *heartbeat  = [self negotiateBetweenClientValue:client.heartbeat
                                                 serverValue:@(server.heartbeat.integerValue)];
    return [[RMQConnectionTuneOk alloc] initWithChannelMax:[[RMQShort alloc] init:channelMax.integerValue]
                                                  frameMax:[[RMQLong alloc] init:frameMax.integerValue]
                                                 heartbeat:[[RMQShort alloc] init:heartbeat.integerValue]];
}

- (RMQConnectionOpen *)connectionOpen {
    return [[RMQConnectionOpen alloc] initWithVirtualHost:[[RMQShortstr alloc] init:self.config.vhost]
                                                reserved1:[[RMQShortstr alloc] init:@""]
                                                  options:0];
}

- (NSNumber *)negotiateBetweenClientValue:(NSNumber *)client
                              serverValue:(NSNumber *)server {
    if ([client isEqualToNumber:@0] || [server isEqualToNumber:@0]) {
        return client.integerValue > server.integerValue ? client : server;
    } else {
        return client.integerValue < server.integerValue ? client : server;
    }
}

- (void)sendMethod:(id<RMQMethod>)amqMethod channelNumber:(NSNumber *)channelNumber {
    RMQFrameset *frameset = [[RMQFrameset alloc] initWithChannelNumber:channelNumber method:amqMethod];
    [self.sender sendFrameset:frameset force:YES];
}

@end