// Copyright Epic Games, Inc. All Rights Reserved.

#include "EditorScriptingHelpers.h"
#include "Utils.h"
#include "Algo/Count.h"
#include "AssetRegistry/AssetData.h"
#include "AssetRegistry/AssetRegistryModule.h"
#include "Misc/FileHelper.h"
#include "Misc/Paths.h"
#include "Editor.h"

namespace EditorScriptingHelpersInternal
{
	// Like !FName::IsValidGroupName(Path)), but with another list and no conversion to from FName
    // InvalidChar may be INVALID_OBJECTPATH_CHARACTERS or INVALID_LONGPACKAGE_CHARACTERS or ...
	FString RemoveFullName(const FString& AnyAssetPath, FString& OutFailureReason)
	{
		FString Result = AnyAssetPath.TrimStartAndEnd();
		int32 NumberOfSpace = Algo::Count(AnyAssetPath, TEXT(' '));

		if (NumberOfSpace == 0)
		{
			return MoveTemp(Result);
		}
		else if (NumberOfSpace > 1)
		{
			OutFailureReason = FString::Printf(TEXT("Can't convert path '%s' because there are too many spaces."), *AnyAssetPath);
			return FString();
		}
		else// if (NumberOfSpace == 1)
		{
			int32 FoundIndex = 0;
			AnyAssetPath.FindChar(TEXT(' '), FoundIndex);
			check(FoundIndex > INDEX_NONE && FoundIndex < AnyAssetPath.Len()); // because of TrimStartAndEnd

			// Confirm that it's a valid Class
			FString ClassName = AnyAssetPath.Left(FoundIndex);

			// Convert \ to /
			ClassName.ReplaceInline(TEXT("\\"), TEXT("/"), ESearchCase::CaseSensitive);

			// Test ClassName for invalid Char
			const int32 StrLen = FCString::Strlen(INVALID_OBJECTNAME_CHARACTERS);
			for (int32 Index = 0; Index < StrLen; ++Index)
			{
				int32 InvalidFoundIndex = 0;
				if (ClassName.FindChar(INVALID_OBJECTNAME_CHARACTERS[Index], InvalidFoundIndex))
				{
					OutFailureReason = FString::Printf(TEXT("Can't convert the path %s because it contains invalid characters (probably spaces)."), *AnyAssetPath);
					return FString();
				}
			}

			// Return the path without the Class name
			return AnyAssetPath.Mid(FoundIndex + 1);
		}
	}
}

bool EditorScriptingHelpers::CheckIfInEditorAndPIE()
{
	if (!IsInGameThread())
	{
		UE_LOG(LogUtils, Error, TEXT("You are not on the main thread."));
		return false;
	}
	if (!GIsEditor)
	{
		UE_LOG(LogUtils, Error, TEXT("You are not in the Editor."));
		return false;
	}
	if (GEditor->PlayWorld || GIsPlayInEditorWorld)
	{
		UE_LOG(LogUtils, Error, TEXT("The Editor is currently in a play mode."));
		return false;
	}
	return true;
}

FString EditorScriptingHelpers::ConvertAnyPathToLongPackagePath(const FString& AnyPath, FString& OutFailureReason)
{
	if (AnyPath.Len() < 2) // minimal length to have /G
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because the Root path need to be specified. ie /Game/"), *AnyPath);
		return FString();
	}

	// Prepare for TryConvertFilenameToLongPackageName

	// Remove class name from Reference Path
	FString TextPath = FPackageName::ExportTextPathToObjectPath(AnyPath);

	// Remove class name Fullname
	TextPath = EditorScriptingHelpersInternal::RemoveFullName(TextPath, OutFailureReason);
	if (TextPath.IsEmpty())
	{
		return FString();
	}

	// Convert \ to /
	TextPath.ReplaceInline(TEXT("\\"), TEXT("/"), ESearchCase::CaseSensitive);
	FPaths::RemoveDuplicateSlashes(TextPath);

	{
		// Remove .
		int32 ObjectDelimiterIdx;
		if (TextPath.FindChar(TEXT('.'), ObjectDelimiterIdx))
		{
			TextPath.LeftInline(ObjectDelimiterIdx);
		}

		// Remove :
		if (TextPath.FindChar(TEXT(':'), ObjectDelimiterIdx))
		{
			TextPath.LeftInline(ObjectDelimiterIdx);
		}
	}

	// Test for invalid characters
	if (!IsAValidPath(TextPath, INVALID_LONGPACKAGE_CHARACTERS, OutFailureReason))
	{
		return FString();
	}

	// Confirm that we have a valid Root Package and get the valid PackagePath /Game/MyFolder
	FString PackagePath;
	if (!FPackageName::TryConvertFilenameToLongPackageName(TextPath, PackagePath, &OutFailureReason))
	{
		return FString();
	}

	if (PackagePath.Len() == 0)
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because of an internal error. TryConvertFilenameToLongPackageName should have return false."), *AnyPath);
		return FString();
	}

	if (PackagePath[0] != TEXT('/'))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert path '%s' because the PackagePath '%s' doesn't start with a '/'."), *AnyPath, *PackagePath);
		return FString();
	}

	if (PackagePath[PackagePath.Len() - 1] == TEXT('/'))
	{
		PackagePath.RemoveAt(PackagePath.Len() - 1);
	}

	if (FPackageName::IsScriptPackage(PackagePath))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because it starts with /Script/"), *AnyPath);
		return FString();
	}
	if (FPackageName::IsMemoryPackage(PackagePath))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because it starts with /Memory/"), *AnyPath);
		return FString();
	}

	// Confirm that the PackagePath start with a valid root
	if (!HasValidRoot(PackagePath))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because it does not map to a root."), *AnyPath);
		return FString();
	}

	return PackagePath;
}

bool EditorScriptingHelpers::HasValidRoot(const FString& ObjectPath)
{
	FString Filename;
	bool bValidRoot = true;
	if (!ObjectPath.IsEmpty() && ObjectPath[ObjectPath.Len() - 1] == TEXT('/'))
	{
		bValidRoot = FPackageName::TryConvertLongPackageNameToFilename(ObjectPath, Filename);
	}
	else
	{
		FString ObjectPathWithSlash = ObjectPath;
		ObjectPathWithSlash.AppendChar(TEXT('/'));
		bValidRoot = FPackageName::TryConvertLongPackageNameToFilename(ObjectPathWithSlash, Filename);
	}

	return bValidRoot;
}

// Test for invalid characters
bool EditorScriptingHelpers::IsAValidPath(const FString& Path, const TCHAR* InvalidChar, FString& OutFailureReason)
{
	const int32 StrLen = FCString::Strlen(InvalidChar);
	for (int32 Index = 0; Index < StrLen; ++Index)
	{
		int32 FoundIndex = 0;
		if (Path.FindChar(InvalidChar[Index], FoundIndex))
		{
			OutFailureReason = FString::Printf(TEXT("Can't convert the path %s because it contains invalid characters."), *Path);
			return false;
		}
	}

	if (Path.Len() > FPlatformMisc::GetMaxPathLength())
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path because it is too long (%d characters). This may interfere with cooking for consoles. Unreal filenames should be no longer than %d characters. Full path value: %s"), Path.Len(), FPlatformMisc::GetMaxPathLength(), *Path);
		return false;
	}
	return true;
}

bool EditorScriptingHelpers::IsAValidPathForCreateNewAsset(const FString& ObjectPath, FString& OutFailureReason)
{
	const FString ObjectName = FPackageName::ObjectPathToObjectName(ObjectPath);

	// Make sure the name is not already a class or otherwise invalid for saving
	FText FailureReason;
	if (!FFileHelper::IsFilenameValidForSaving(ObjectName, FailureReason))
	{
		OutFailureReason = FailureReason.ToString();
		return false;
	}

	// Make sure the new name only contains valid characters
	if (!FName::IsValidXName(ObjectName, INVALID_OBJECTNAME_CHARACTERS INVALID_LONGPACKAGE_CHARACTERS, &FailureReason))
	{
		OutFailureReason = FailureReason.ToString();
		return false;
	}

	// Make sure we are not creating an FName that is too large
	if (ObjectPath.Len() >= NAME_SIZE)
	{
		OutFailureReason = TEXT("This asset name is too long (") + FString::FromInt(ObjectPath.Len()) + TEXT(" characters), the maximum is ") + FString::FromInt(NAME_SIZE - 1) + TEXT(". Please choose a shorter name.");
		return false;
	}

	FAssetRegistryModule& AssetRegistryModule = FModuleManager::LoadModuleChecked<FAssetRegistryModule>("AssetRegistry");
	FAssetData AssetData = AssetRegistryModule.Get().GetAssetByObjectPath(*ObjectPath);
	if (AssetData.IsValid())
	{
		OutFailureReason = TEXT("An asset already exists at this location.");
		return false;
	}

	return true;
}

FString EditorScriptingHelpers::ConvertAnyPathToObjectPath(const FString& AnyAssetPath, FString& OutFailureReason)
{
	if (AnyAssetPath.Len() < 2) // minimal length to have /G
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because the Root path need to be specified. ie /Game/"), *AnyAssetPath);
		return FString();
	}

	// Remove class name from Reference Path
	FString TextPath = FPackageName::ExportTextPathToObjectPath(AnyAssetPath);

	// Remove class name Fullname
	TextPath = EditorScriptingHelpersInternal::RemoveFullName(TextPath, OutFailureReason);
	if (TextPath.IsEmpty())
	{
		return FString();
	}

	// Extract the subobject path if any
	FString SubObjectPath;
	int32 SubObjectDelimiterIdx;
	if (TextPath.FindChar(SUBOBJECT_DELIMITER_CHAR, SubObjectDelimiterIdx))
	{
		SubObjectPath = TextPath.Mid(SubObjectDelimiterIdx + 1);
		TextPath.LeftInline(SubObjectDelimiterIdx);
	}

	// Convert \ to /
	TextPath.ReplaceInline(TEXT("\\"), TEXT("/"), ESearchCase::CaseSensitive);
	FPaths::RemoveDuplicateSlashes(TextPath);

	// Get asset full name, i.e."PackageName.ObjectName:InnerAssetName.2ndInnerAssetName" from "/Game/Folder/PackageName.ObjectName:InnerAssetName.2ndInnerAssetName"
	FString AssetFullName;
	{
		// Get everything after the last slash
		int32 IndexOfLastSlash = INDEX_NONE;
		TextPath.FindLastChar('/', IndexOfLastSlash);

		FString Folders = TextPath.Left(IndexOfLastSlash);
		// Test for invalid characters
		if (!IsAValidPath(Folders, INVALID_LONGPACKAGE_CHARACTERS, OutFailureReason))
		{
			return FString();
		}

		AssetFullName = TextPath.Mid(IndexOfLastSlash + 1);
	}

	// Get the object name
	FString ObjectName = FPackageName::ObjectPathToObjectName(AssetFullName);
	if (ObjectName.IsEmpty())
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because it doesn't contain an asset name."), *AnyAssetPath);
		return FString();
	}

	// Test for invalid characters
	if (!IsAValidPath(ObjectName, INVALID_OBJECTNAME_CHARACTERS, OutFailureReason))
	{
		return FString();
	}

	// Confirm that we have a valid Root Package and get the valid PackagePath /Game/MyFolder/MyAsset
	FString PackagePath;
	if (!FPackageName::TryConvertFilenameToLongPackageName(TextPath, PackagePath, &OutFailureReason))
	{
		return FString();
	}

	if (PackagePath.Len() == 0)
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert path '%s' because the PackagePath is empty."), *AnyAssetPath);
		return FString();
	}

	if (PackagePath[0] != TEXT('/'))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert path '%s' because the PackagePath '%s' doesn't start with a '/'."), *AnyAssetPath, *PackagePath);
		return FString();
	}

	FString ObjectPath = FString::Printf(TEXT("%s.%s"), *PackagePath, *ObjectName);

	if (FPackageName::IsScriptPackage(ObjectPath))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because it start with /Script/"), *AnyAssetPath);
		return FString();
	}
	if (FPackageName::IsMemoryPackage(ObjectPath))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because it start with /Memory/"), *AnyAssetPath);
		return FString();
	}

	// Confirm that the PackagePath starts with a valid root
	if (!HasValidRoot(PackagePath))
	{
		OutFailureReason = FString::Printf(TEXT("Can't convert the path '%s' because it does not map to a root."), *AnyAssetPath);
		return FString();
	}

	return ObjectPath;
}