package azblob

import "sync/atomic"

// AtomicMorpherInt32 identifies a method passed to and invoked by the AtomicMorphInt32 function.

// The AtomicMorpher callback is passed a startValue and based on this value it returns

// what the new value should be and the result that AtomicMorph should return to its caller.

type atomicMorpherInt32 func(startVal int32) (val int32, morphResult interface{})

const targetAndMorpherMustNotBeNil = "target and morpher must not be nil"

// AtomicMorph atomically morphs target in to new value (and result) as indicated bythe AtomicMorpher callback function.

func atomicMorphInt32(target *int32, morpher atomicMorpherInt32) interface{} {

	for {

		currentVal := atomic.LoadInt32(target)

		desiredVal, morphResult := morpher(currentVal)

		if atomic.CompareAndSwapInt32(target, currentVal, desiredVal) {

			return morphResult

		}

	}

}

// AtomicMorpherUint32 identifies a method passed to and invoked by the AtomicMorph function.

// The AtomicMorpher callback is passed a startValue and based on this value it returns

// what the new value should be and the result that AtomicMorph should return to its caller.

type atomicMorpherUint32 func(startVal uint32) (val uint32, morphResult interface{})

// AtomicMorph atomically morphs target in to new value (and result) as indicated bythe AtomicMorpher callback function.

func atomicMorphUint32(target *uint32, morpher atomicMorpherUint32) interface{} {

	for {

		currentVal := atomic.LoadUint32(target)

		desiredVal, morphResult := morpher(currentVal)

		if atomic.CompareAndSwapUint32(target, currentVal, desiredVal) {

			return morphResult

		}

	}

}

// AtomicMorpherUint64 identifies a method passed to and invoked by the AtomicMorphUint64 function.

// The AtomicMorpher callback is passed a startValue and based on this value it returns

// what the new value should be and the result that AtomicMorph should return to its caller.

type atomicMorpherInt64 func(startVal int64) (val int64, morphResult interface{})

// AtomicMorph atomically morphs target in to new value (and result) as indicated bythe AtomicMorpher callback function.

func atomicMorphInt64(target *int64, morpher atomicMorpherInt64) interface{} {

	for {

		currentVal := atomic.LoadInt64(target)

		desiredVal, morphResult := morpher(currentVal)

		if atomic.CompareAndSwapInt64(target, currentVal, desiredVal) {

			return morphResult

		}

	}

}

// AtomicMorpherUint64 identifies a method passed to and invoked by the AtomicMorphUint64 function.

// The AtomicMorpher callback is passed a startValue and based on this value it returns

// what the new value should be and the result that AtomicMorph should return to its caller.

type atomicMorpherUint64 func(startVal uint64) (val uint64, morphResult interface{})

// AtomicMorph atomically morphs target in to new value (and result) as indicated bythe AtomicMorpher callback function.

func atomicMorphUint64(target *uint64, morpher atomicMorpherUint64) interface{} {

	for {

		currentVal := atomic.LoadUint64(target)

		desiredVal, morphResult := morpher(currentVal)

		if atomic.CompareAndSwapUint64(target, currentVal, desiredVal) {

			return morphResult

		}

	}

}