/*
Gomega is the Ginkgo BDD-style testing framework's preferred matcher library.

The godoc documentation describes Gomega's API.  More comprehensive documentation (with examples!) is available at http://onsi.github.io/gomega/

Gomega on Github: http://github.com/onsi/gomega

Learn more about Ginkgo online: http://onsi.github.io/ginkgo

Ginkgo on Github: http://github.com/onsi/ginkgo

Gomega is MIT-Licensed
*/
package gomega

import (
	"fmt"
	"reflect"
	"time"

	"github.com/onsi/gomega/internal/assertion"
	"github.com/onsi/gomega/internal/asyncassertion"
	"github.com/onsi/gomega/internal/testingtsupport"
	"github.com/onsi/gomega/types"
)

const GOMEGA_VERSION = "1.0"

var globalFailHandler types.GomegaFailHandler

var defaultEventuallyTimeout = time.Second
var defaultEventuallyPollingInterval = 10 * time.Millisecond
var defaultConsistentlyDuration = 100 * time.Millisecond
var defaultConsistentlyPollingInterval = 10 * time.Millisecond

//RegisterFailHandler connects Ginkgo to Gomega.  When a matcher fails
//the fail handler passed into RegisterFailHandler is called.
func RegisterFailHandler(handler types.GomegaFailHandler) {
	globalFailHandler = handler
}

//RegisterTestingT connects Gomega to Golang's XUnit style
//Testing.T tests.  You'll need to call this at the top of each XUnit style test:
//
// func TestFarmHasCow(t *testing.T) {
//     RegisterTestingT(t)
//
//	   f := farm.New([]string{"Cow", "Horse"})
//     Expect(f.HasCow()).To(BeTrue(), "Farm should have cow")
// }
//
// Note that this *testing.T is registered *globally* by Gomega (this is why you don't have to
// pass `t` down to the matcher itself).  This means that you cannot run the XUnit style tests
// in parallel as the global fail handler cannot point to more than one testing.T at a time.
//
// (As an aside: Ginkgo gets around this limitation by running parallel tests in different *processes*).
func RegisterTestingT(t types.GomegaTestingT) {
	RegisterFailHandler(testingtsupport.BuildTestingTGomegaFailHandler(t))
}

//InterceptGomegaHandlers runs a given callback and returns an array of
//failure messages generated by any Gomega assertions within the callback.
//
//This is accomplished by temporarily replacing the *global* fail handler
//with a fail handler that simply annotates failures.  The original fail handler
//is reset when InterceptGomegaFailures returns.
//
//This is most useful when testing custom matchers, but can also be used to check
//on a value using a Gomega assertion without causing a test failure.
func InterceptGomegaFailures(f func()) []string {
	originalHandler := globalFailHandler
	failures := []string{}
	RegisterFailHandler(func(message string, callerSkip ...int) {
		failures = append(failures, message)
	})
	f()
	RegisterFailHandler(originalHandler)
	return failures
}

//Ω wraps an actual value allowing assertions to be made on it:
//	Ω("foo").Should(Equal("foo"))
//
//If Ω is passed more than one argument it will pass the *first* argument to the matcher.
//All subsequent arguments will be required to be nil/zero.
//
//This is convenient if you want to make an assertion on a method/function that returns
//a value and an error - a common patter in Go.
//
//For example, given a function with signature:
//  func MyAmazingThing() (int, error)
//
//Then:
//    Ω(MyAmazingThing()).Should(Equal(3))
//Will succeed only if `MyAmazingThing()` returns `(3, nil)`
//
//Ω and Expect are identical
func Ω(actual interface{}, extra ...interface{}) GomegaAssertion {
	return ExpectWithOffset(0, actual, extra...)
}

//Expect wraps an actual value allowing assertions to be made on it:
//	Expect("foo").To(Equal("foo"))
//
//If Expect is passed more than one argument it will pass the *first* argument to the matcher.
//All subsequent arguments will be required to be nil/zero.
//
//This is convenient if you want to make an assertion on a method/function that returns
//a value and an error - a common patter in Go.
//
//For example, given a function with signature:
//  func MyAmazingThing() (int, error)
//
//Then:
//    Expect(MyAmazingThing()).Should(Equal(3))
//Will succeed only if `MyAmazingThing()` returns `(3, nil)`
//
//Expect and Ω are identical
func Expect(actual interface{}, extra ...interface{}) GomegaAssertion {
	return ExpectWithOffset(0, actual, extra...)
}

//ExpectWithOffset wraps an actual value allowing assertions to be made on it:
//    ExpectWithOffset(1, "foo").To(Equal("foo"))
//
//Unlike `Expect` and `Ω`, `ExpectWithOffset` takes an additional integer argument
//this is used to modify the call-stack offset when computing line numbers.
//
//This is most useful in helper functions that make assertions.  If you want Gomega's
//error message to refer to the calling line in the test (as opposed to the line in the helper function)
//set the first argument of `ExpectWithOffset` appropriately.
func ExpectWithOffset(offset int, actual interface{}, extra ...interface{}) GomegaAssertion {
	return assertion.New(actual, globalFailHandler, offset, extra...)
}

//Eventually wraps an actual value allowing assertions to be made on it.
//The assertion is tried periodically until it passes or a timeout occurs.
//
//Both the timeout and polling interval are configurable as optional arguments:
//The first optional argument is the timeout
//The second optional argument is the polling interval
//
//Both intervals can either be specified as time.Duration, parsable duration strings or as floats/integers.  In the
//last case they are interpreted as seconds.
//
//If Eventually is passed an actual that is a function taking no arguments and returning at least one value,
//then Eventually will call the function periodically and try the matcher against the function's first return value.
//
//Example:
//
//    Eventually(func() int {
//        return thingImPolling.Count()
//    }).Should(BeNumerically(">=", 17))
//
//Note that this example could be rewritten:
//
//    Eventually(thingImPolling.Count).Should(BeNumerically(">=", 17))
//
//If the function returns more than one value, then Eventually will pass the first value to the matcher and
//assert that all other values are nil/zero.
//This allows you to pass Eventually a function that returns a value and an error - a common pattern in Go.
//
//For example, consider a method that returns a value and an error:
//    func FetchFromDB() (string, error)
//
//Then
//    Eventually(FetchFromDB).Should(Equal("hasselhoff"))
//
//Will pass only if the the returned error is nil and the returned string passes the matcher.
//
//Eventually's default timeout is 1 second, and its default polling interval is 10ms
func Eventually(actual interface{}, intervals ...interface{}) GomegaAsyncAssertion {
	return EventuallyWithOffset(0, actual, intervals...)
}

//EventuallyWithOffset operates like Eventually but takes an additional
//initial argument to indicate an offset in the call stack.  This is useful when building helper
//functions that contain matchers.  To learn more, read about `ExpectWithOffset`.
func EventuallyWithOffset(offset int, actual interface{}, intervals ...interface{}) GomegaAsyncAssertion {
	timeoutInterval := defaultEventuallyTimeout
	pollingInterval := defaultEventuallyPollingInterval
	if len(intervals) > 0 {
		timeoutInterval = toDuration(intervals[0])
	}
	if len(intervals) > 1 {
		pollingInterval = toDuration(intervals[1])
	}
	return asyncassertion.New(asyncassertion.AsyncAssertionTypeEventually, actual, globalFailHandler, timeoutInterval, pollingInterval, offset)
}

//Consistently wraps an actual value allowing assertions to be made on it.
//The assertion is tried periodically and is required to pass for a period of time.
//
//Both the total time and polling interval are configurable as optional arguments:
//The first optional argument is the duration that Consistently will run for
//The second optional argument is the polling interval
//
//Both intervals can either be specified as time.Duration, parsable duration strings or as floats/integers.  In the
//last case they are interpreted as seconds.
//
//If Consistently is passed an actual that is a function taking no arguments and returning at least one value,
//then Consistently will call the function periodically and try the matcher against the function's first return value.
//
//If the function returns more than one value, then Consistently will pass the first value to the matcher and
//assert that all other values are nil/zero.
//This allows you to pass Consistently a function that returns a value and an error - a common pattern in Go.
//
//Consistently is useful in cases where you want to assert that something *does not happen* over a period of tiem.
//For example, you want to assert that a goroutine does *not* send data down a channel.  In this case, you could:
//
//  Consistently(channel).ShouldNot(Receive())
//
//Consistently's default duration is 100ms, and its default polling interval is 10ms
func Consistently(actual interface{}, intervals ...interface{}) GomegaAsyncAssertion {
	return ConsistentlyWithOffset(0, actual, intervals...)
}

//ConsistentlyWithOffset operates like Consistnetly but takes an additional
//initial argument to indicate an offset in the call stack.  This is useful when building helper
//functions that contain matchers.  To learn more, read about `ExpectWithOffset`.
func ConsistentlyWithOffset(offset int, actual interface{}, intervals ...interface{}) GomegaAsyncAssertion {
	timeoutInterval := defaultConsistentlyDuration
	pollingInterval := defaultConsistentlyPollingInterval
	if len(intervals) > 0 {
		timeoutInterval = toDuration(intervals[0])
	}
	if len(intervals) > 1 {
		pollingInterval = toDuration(intervals[1])
	}
	return asyncassertion.New(asyncassertion.AsyncAssertionTypeConsistently, actual, globalFailHandler, timeoutInterval, pollingInterval, offset)
}

//Set the default timeout duration for Eventually.  Eventually will repeatedly poll your condition until it succeeds, or until this timeout elapses.
func SetDefaultEventuallyTimeout(t time.Duration) {
	defaultEventuallyTimeout = t
}

//Set the default polling interval for Eventually.
func SetDefaultEventuallyPollingInterval(t time.Duration) {
	defaultEventuallyPollingInterval = t
}

//Set the default duration for Consistently.  Consistently will verify that your condition is satsified for this long.
func SetDefaultConsistentlyDuration(t time.Duration) {
	defaultConsistentlyDuration = t
}

//Set the default polling interval for Consistently.
func SetDefaultConsistentlyPollingInterval(t time.Duration) {
	defaultConsistentlyPollingInterval = t
}

//GomegaAsyncAssertion is returned by Eventually and Consistently and polls the actual value passed into Eventually against
//the matcher passed to the Should and ShouldNot methods.
//
//Both Should and ShouldNot take a variadic optionalDescription argument.  This is passed on to
//fmt.Sprintf() and is used to annotate failure messages.  This allows you to make your failure messages more
//descriptive
//
//Both Should and ShouldNot return a boolean that is true if the assertion passed and false if it failed.
//
//Example:
//
//  Eventually(myChannel).Should(Receive(), "Something should have come down the pipe.")
//  Consistently(myChannel).ShouldNot(Receive(), "Nothing should have come down the pipe.")
type GomegaAsyncAssertion interface {
	Should(matcher types.GomegaMatcher, optionalDescription ...interface{}) bool
	ShouldNot(matcher types.GomegaMatcher, optionalDescription ...interface{}) bool
}

//GomegaAssertion is returned by Ω and Expect and compares the actual value to the matcher
//passed to the Should/ShouldNot and To/ToNot/NotTo methods.
//
//Typically Should/ShouldNot are used with Ω and To/ToNot/NotTo are used with Expect
//though this is not enforced.
//
//All methods take a variadic optionalDescription argument.  This is passed on to fmt.Sprintf()
//and is used to annotate failure messages.
//
//All methods return a bool that is true if hte assertion passed and false if it failed.
//
//Example:
//
//   Ω(farm.HasCow()).Should(BeTrue(), "Farm %v should have a cow", farm)
type GomegaAssertion interface {
	Should(matcher types.GomegaMatcher, optionalDescription ...interface{}) bool
	ShouldNot(matcher types.GomegaMatcher, optionalDescription ...interface{}) bool

	To(matcher types.GomegaMatcher, optionalDescription ...interface{}) bool
	ToNot(matcher types.GomegaMatcher, optionalDescription ...interface{}) bool
	NotTo(matcher types.GomegaMatcher, optionalDescription ...interface{}) bool
}

//OmegaMatcher is deprecated in favor of the better-named and better-organized types.GomegaMatcher but sticks around to support existing code that uses it
type OmegaMatcher types.GomegaMatcher

func toDuration(input interface{}) time.Duration {
	duration, ok := input.(time.Duration)
	if ok {
		return duration
	}

	value := reflect.ValueOf(input)
	kind := reflect.TypeOf(input).Kind()

	if reflect.Int <= kind && kind <= reflect.Int64 {
		return time.Duration(value.Int()) * time.Second
	} else if reflect.Uint <= kind && kind <= reflect.Uint64 {
		return time.Duration(value.Uint()) * time.Second
	} else if reflect.Float32 <= kind && kind <= reflect.Float64 {
		return time.Duration(value.Float() * float64(time.Second))
	} else if reflect.String == kind {
		duration, err := time.ParseDuration(value.String())
		if err != nil {
			panic(fmt.Sprintf("%#v is not a valid parsable duration string.", input))
		}
		return duration
	}

	panic(fmt.Sprintf("%v is not a valid interval.  Must be time.Duration, parsable duration string or a number.", input))
}