// 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.
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// The Original Code is RabbitMQ
//
// The Initial Developer of the Original Code is Pivotal Software, Inc.
// All Rights Reserved.
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// of the Apache Standard license (the "ASL License"), in which case the
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// 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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// ---------------------------------------------------------------------------

#import "RMQConnectionRecover.h"

@interface RMQConnectionRecover ()
@property (nonatomic, readwrite) NSNumber *interval;
@property (nonatomic, readwrite) NSUInteger attempts;
@property (nonatomic, readwrite) NSUInteger attemptLimit;
@property (nonatomic, readwrite) BOOL onlyErrors;
@property (nonatomic, readwrite) id<RMQHeartbeatSender> heartbeatSender;
@property (nonatomic, readwrite) id<RMQLocalSerialQueue> commandQueue;
@property (nonatomic, readwrite) id<RMQConnectionDelegate> delegate;
@end

@implementation RMQConnectionRecover

- (instancetype)initWithInterval:(NSNumber *)interval
                    attemptLimit:(NSNumber *)attemptLimit
                      onlyErrors:(BOOL)onlyErrors
                 heartbeatSender:(id<RMQHeartbeatSender>)heartbeatSender
                    commandQueue:(id<RMQLocalSerialQueue>)commandQueue
                        delegate:(id<RMQConnectionDelegate>)delegate {
    self = [super init];
    if (self) {
        self.interval = interval;
        self.attempts = 0;
        self.onlyErrors = onlyErrors;
        self.attemptLimit = attemptLimit.integerValue;
        self.heartbeatSender = heartbeatSender;
        self.commandQueue = commandQueue;
        self.delegate = delegate;
    }
    return self;
}

-  (void)recover:(id<RMQStarter>)connection
channelAllocator:(id<RMQChannelAllocator>)allocator
           error:(NSError *)error {
    [self.commandQueue enqueue:^{
        [self.heartbeatSender stop];
    }];

    if ((self.onlyErrors && !error) || [self currentAttemptBeyondLimit]) {
        return;
    }

    [self.commandQueue enqueue:^{
        [self.delegate willStartRecoveryWithConnection:(RMQConnection *)connection];
    }];

    [self.commandQueue delayedBy:self.interval enqueue:^{
        [self.delegate startingRecoveryWithConnection:(RMQConnection *)connection];
        [connection start:^{
            [self.commandQueue enqueue:^{
                for (id<RMQChannel> ch in allocator.allocatedUserChannels) {
                    [ch recover];
                }
                self.attempts = 0;
                [self.delegate recoveredConnection:(RMQConnection *)connection];
            }];
        }];
    }];
}

# pragma mark - Private

- (BOOL)currentAttemptBeyondLimit {
    return self.interval.integerValue == 0 || ++self.attempts > self.attemptLimit;
}

@end