#include "pch.h"
#include <winrt/base.h>
#include <memory>
#include <mutex>
#include <optional>

#include "Renaming.h"
#include <Helpers.h>
#include "MetadataPatternExtractor.h"
#include "PowerRenameRegEx.h"
namespace fs = std::filesystem;

bool DoRename(CComPtr<IPowerRenameRegEx>& spRenameRegEx, unsigned long& itemEnumIndex, CComPtr<IPowerRenameItem>& spItem)
{
    bool wouldRename = false;
    DWORD flags = 0;
    winrt::check_hresult(spRenameRegEx->GetFlags(&flags));

    PWSTR replaceTerm = nullptr;
    bool useFileTime = false;
    bool useMetadata = false;

    winrt::check_hresult(spRenameRegEx->GetReplaceTerm(&replaceTerm));

    if (isFileTimeUsed(replaceTerm))
    {
        useFileTime = true;
    }

    int id = -1;
    winrt::check_hresult(spItem->GetId(&id));

    bool isFolder = false;
    bool isSubFolderContent = false;
    winrt::check_hresult(spItem->GetIsFolder(&isFolder));
    winrt::check_hresult(spItem->GetIsSubFolderContent(&isSubFolderContent));

    // Get metadata type to check if metadata patterns are used
    PowerRenameLib::MetadataType metadataType;
    HRESULT hr = spRenameRegEx->GetMetadataType(&metadataType);
    if (FAILED(hr))
    {
        // Fallback to default metadata type if call fails
        metadataType = PowerRenameLib::MetadataType::EXIF;
    }

    // Check if metadata is used AND if this file type supports metadata
    // Get file path early for metadata type checking and reuse later
    PWSTR filePath = nullptr;
    winrt::check_hresult(spItem->GetPath(&filePath));
    std::wstring filePathStr(filePath);  // Copy once for reuse
    CoTaskMemFree(filePath);  // Free immediately after copying

    if (isMetadataUsed(replaceTerm, metadataType, filePathStr.c_str(), isFolder))
    {
        useMetadata = true;
    }

    CoTaskMemFree(replaceTerm);
    if ((isFolder && (flags & PowerRenameFlags::ExcludeFolders)) ||
        (!isFolder && (flags & PowerRenameFlags::ExcludeFiles)) ||
        (isSubFolderContent && (flags & PowerRenameFlags::ExcludeSubfolders)) ||
        (isFolder && (flags & PowerRenameFlags::ExtensionOnly)))
    {
        // Exclude this item from renaming.  Ensure new name is cleared.
        winrt::check_hresult(spItem->PutNewName(nullptr));

        return wouldRename;
    }

    PWSTR originalName = nullptr;
    winrt::check_hresult(spItem->GetOriginalName(&originalName));

    PWSTR currentNewName = nullptr;
    winrt::check_hresult(spItem->GetNewName(&currentNewName));

    wchar_t sourceName[MAX_PATH] = { 0 };

    if (isFolder)
    {
        StringCchCopy(sourceName, ARRAYSIZE(sourceName), originalName);
    }
    else
    {
        if (flags & NameOnly)
        {
            StringCchCopy(sourceName, ARRAYSIZE(sourceName), fs::path(originalName).stem().c_str());
        }
        else if (flags & ExtensionOnly)
        {
            std::wstring extension = fs::path(originalName).extension().wstring();
            if (!extension.empty() && extension.front() == '.')
            {
                extension = extension.erase(0, 1);
            }
            StringCchCopy(sourceName, ARRAYSIZE(sourceName), extension.c_str());
        }
        else
        {
            StringCchCopy(sourceName, ARRAYSIZE(sourceName), originalName);
        }
    }

    SYSTEMTIME fileTime = { 0 };

    if (useFileTime)
    {
        winrt::check_hresult(spItem->GetTime(flags, &fileTime));
        winrt::check_hresult(spRenameRegEx->PutFileTime(fileTime));
    }

    if (useMetadata)
    {
        // Extract metadata patterns from the file
        // Note: filePathStr was already obtained and saved earlier for reuse

        // Get metadata type using the interface method
        PowerRenameLib::MetadataType metadataType;
        HRESULT hr = spRenameRegEx->GetMetadataType(&metadataType);
        if (FAILED(hr))
        {
            // Fallback to default metadata type if call fails
            metadataType = PowerRenameLib::MetadataType::EXIF;
        }
        // Extract all patterns for the selected metadata type
        // At this point we know the file is a supported image format (jpg/jpeg/png/tif/tiff)
        static std::mutex s_metadataMutex; // Mutex to protect static variables
        static std::once_flag s_metadataExtractorInitFlag;
        static std::shared_ptr<PowerRenameLib::MetadataPatternExtractor> s_metadataExtractor;
        static std::optional<PowerRenameLib::MetadataType> s_activeMetadataType;

        // Initialize the extractor only once
        std::call_once(s_metadataExtractorInitFlag, []() {
            s_metadataExtractor = std::make_shared<PowerRenameLib::MetadataPatternExtractor>();
        });

        // Protect access to shared state
        {
            std::lock_guard<std::mutex> lock(s_metadataMutex);

            // Clear cache if metadata type has changed
            if (s_activeMetadataType.has_value() && s_activeMetadataType.value() != metadataType)
            {
                s_metadataExtractor->ClearCache();
            }

            // Update the active metadata type
            s_activeMetadataType = metadataType;
        }

        // Extract patterns (this can be done outside the lock if ExtractPatterns is thread-safe)
        PowerRenameLib::MetadataPatternMap patterns = s_metadataExtractor->ExtractPatterns(filePathStr, metadataType);
        
        // Always call PutMetadataPatterns to ensure all patterns get replaced
        // Even if empty, this keeps metadata placeholders consistent when no values are extracted
        winrt::check_hresult(spRenameRegEx->PutMetadataPatterns(patterns));
    }

    PWSTR newName = nullptr;

    // Failure here means we didn't match anything or had nothing to match
    // Call put_newName with null in that case to reset it
    winrt::check_hresult(spRenameRegEx->Replace(sourceName, &newName, itemEnumIndex));

    if (useFileTime)
    {
        winrt::check_hresult(spRenameRegEx->ResetFileTime());
    }

    if (useMetadata)
    {
        winrt::check_hresult(spRenameRegEx->ResetMetadata());
    }
    wchar_t resultName[MAX_PATH] = { 0 };

    PWSTR newNameToUse = nullptr;

    // newName == nullptr likely means we have an empty search string.  We should leave newNameToUse
    // as nullptr so we clear the renamed column
    // Except string transformation is selected.

    if (newName == nullptr && (flags & Uppercase || flags & Lowercase || flags & Titlecase || flags & Capitalized))
    {
        SHStrDup(sourceName, &newName);
    }

    if (newName != nullptr)
    {
        newNameToUse = resultName;

        if (isFolder)
        {
            StringCchCopy(resultName, ARRAYSIZE(resultName), newName);
        }
        else
        {
            if (flags & NameOnly)
            {
                StringCchPrintf(resultName, ARRAYSIZE(resultName), L"%s%s", newName, fs::path(originalName).extension().c_str());
            }
            else if (flags & ExtensionOnly)
            {
                std::wstring extension = fs::path(originalName).extension().wstring();
                if (!extension.empty())
                {
                    StringCchPrintf(resultName, ARRAYSIZE(resultName), L"%s.%s", fs::path(originalName).stem().c_str(), newName);
                }
                else
                {
                    StringCchCopy(resultName, ARRAYSIZE(resultName), originalName);
                }
            }
            else
            {
                StringCchCopy(resultName, ARRAYSIZE(resultName), newName);
            }
        }
    }

    wchar_t trimmedName[MAX_PATH] = { 0 };
    if (newNameToUse != nullptr)
    {
        winrt::check_hresult(GetTrimmedFileName(trimmedName, ARRAYSIZE(trimmedName), newNameToUse));
        newNameToUse = trimmedName;
    }

    wchar_t transformedName[MAX_PATH] = { 0 };
    if (newNameToUse != nullptr && (flags & Uppercase || flags & Lowercase || flags & Titlecase || flags & Capitalized))
    {
        try
        {
            winrt::check_hresult(GetTransformedFileName(transformedName, ARRAYSIZE(transformedName), newNameToUse, flags, isFolder));
        }
        catch (...)
        {
        }
        newNameToUse = transformedName;
    }

    // No change from originalName so set newName to
    // null so we clear it from our UI as well.
    if (lstrcmp(originalName, newNameToUse) == 0)
    {
        newNameToUse = nullptr;
    }

    spItem->PutStatus(PowerRenameItemRenameStatus::ShouldRename);
    if (newNameToUse != nullptr)
    {
        wouldRename = true;
        std::wstring newNameToUseWstr{ newNameToUse };
        PWSTR path = nullptr;
        spItem->GetPath(&path);

        // Following characters cannot be used for file names.
        // Ref https://learn.microsoft.com/windows/win32/fileio/naming-a-file#naming-conventions
        if (newNameToUseWstr.contains('<') ||
            newNameToUseWstr.contains('>') ||
            newNameToUseWstr.contains(':') ||
            newNameToUseWstr.contains('"') ||
            newNameToUseWstr.contains('\\') ||
            newNameToUseWstr.contains('/') ||
            newNameToUseWstr.contains('|') ||
            newNameToUseWstr.contains('?') ||
            newNameToUseWstr.contains('*'))
        {
            spItem->PutStatus(PowerRenameItemRenameStatus::ItemNameInvalidChar);
            wouldRename = false;
        }
        // Max file path is 260 and max folder path is 247.
        // Ref https://learn.microsoft.com/windows/win32/fileio/maximum-file-path-limitation?tabs=registry
        else if ((isFolder && lstrlen(path) + (lstrlen(newNameToUse) - lstrlen(originalName)) > 247) ||
                 lstrlen(path) + (lstrlen(newNameToUse) - lstrlen(originalName)) > 260)
        {
            spItem->PutStatus(PowerRenameItemRenameStatus::ItemNameTooLong);
            wouldRename = false;
        }
    }

    winrt::check_hresult(spItem->PutNewName(newNameToUse));

    CoTaskMemFree(newName);
    CoTaskMemFree(currentNewName);
    CoTaskMemFree(originalName);

    return wouldRename;
}