namespace Bunit;

/// <summary>

/// Represents an invocation of JavaScript via the JSRuntime Mock.

/// </summary>

public readonly struct JSRuntimeInvocation : IEquatable<JSRuntimeInvocation>

{

/// <summary>

/// Gets the identifier used in the invocation.

/// </summary>

public string Identifier { get; }

/// <summary>

/// Gets the cancellation token used in the invocation, if any.

/// </summary>

public CancellationToken? CancellationToken { get; }

/// <summary>

/// Gets the arguments used in the invocation.

/// </summary>

public IReadOnlyList<object?> Arguments { get; }

/// <summary>

/// Gets whether the invocation has a <c>void</c> return type.

/// </summary>

public bool IsVoidResultInvocation { get; }

/// <summary>

/// Gets the result type of the invocation. If <see cref="IsVoidResultInvocation"/> then

/// this will be of type <see cref="object"/>.

/// </summary>

public Type ResultType { get; }

/// <summary>

/// Gets the name of the method that initiated the invocation, e.g. <c>InvokeAsync</c> or <c>Invoke</c>.

/// </summary>

public string InvocationMethodName { get; }

/// <summary>

/// Initializes a new instance of the <see cref="JSRuntimeInvocation"/> struct.

/// </summary>

public JSRuntimeInvocation(string identifier, Type resultType, string invocationMethodName)

: this(identifier, null, Array.Empty<object?>(), resultType, invocationMethodName)

{ }

/// <summary>

/// Initializes a new instance of the <see cref="JSRuntimeInvocation"/> struct.

/// </summary>

public JSRuntimeInvocation(string identifier, object?[] args, Type resultType, string invocationMethodName)

: this(identifier, null, args, resultType, invocationMethodName)

{ }

/// <summary>

/// Initializes a new instance of the <see cref="JSRuntimeInvocation"/> struct.

/// </summary>

public JSRuntimeInvocation(

string identifier,

CancellationToken? cancellationToken,

object?[]? args,

Type resultType,

string invocationMethodName)

{

Identifier = identifier;

CancellationToken = cancellationToken;

Arguments = args ?? Array.Empty<object?>();

ResultType = resultType;

InvocationMethodName = invocationMethodName;

IsVoidResultInvocation = resultType == typeof(Microsoft.JSInterop.Infrastructure.IJSVoidResult);

}

/// <inheritdoc/>

public bool Equals(JSRuntimeInvocation other)

=> Identifier.Equals(other.Identifier, StringComparison.Ordinal)

&& CancellationToken == other.CancellationToken

&& ArgumentsEqual(Arguments, other.Arguments)

&& ResultType == other.ResultType

&& InvocationMethodName.Equals(other.InvocationMethodName, StringComparison.Ordinal);

/// <inheritdoc/>

public override bool Equals(object? obj) => obj is JSRuntimeInvocation other && Equals(other);

/// <inheritdoc/>

public override int GetHashCode()

{

var hash = default(HashCode);

hash.Add(Identifier);

hash.Add(CancellationToken);

hash.Add(ResultType);

hash.Add(InvocationMethodName);

for (var i = 0; i < Arguments.Count; i++)

{

hash.Add(Arguments[i]);

}

return hash.ToHashCode();

}

/// <summary>

/// Verify whether <paramref name="left"/> and <paramref name="right"/>

/// <see cref="JSRuntimeInvocation"/> is equal.

/// </summary>

public static bool operator ==(JSRuntimeInvocation left, JSRuntimeInvocation right) => left.Equals(right);

/// <summary>

/// Verify whether <paramref name="left"/> and <paramref name="right"/>

/// <see cref="JSRuntimeInvocation"/> is not equal.

/// </summary>

public static bool operator !=(JSRuntimeInvocation left, JSRuntimeInvocation right) => !(left == right);

private static bool ArgumentsEqual(IReadOnlyList<object?> left, IReadOnlyList<object?> right)

{

if (left.Count != right.Count)

return false;

for (var i = 0; i < left.Count; i++)

{

var l = left[i];

var r = right[i];

if (l is null)

{

if (r is object)

return false;

}

else

{

if (!l.Equals(right[i]))

return false;

}

}

return true;

}

}