XCEngine/engine/src/Core/IO/ResourceFileSystem.cpp

#include "Resources/ResourceFileSystem.h"
#include <algorithm>
#include <cstdio>

namespace XCEngine {
namespace Resources {

ResourceFileSystem::ResourceFileSystem() = default;
ResourceFileSystem::~ResourceFileSystem() {
    Shutdown();
}

void ResourceFileSystem::Initialize(const Containers::String& rootPath) {
    std::lock_guard lock(m_mutex);
    m_rootPath = rootPath;
}

void ResourceFileSystem::Shutdown() {
    std::lock_guard lock(m_mutex);
    
    m_archives.Clear();
    m_directories.Clear();
    m_infoCache.Clear();
    m_rootPath = "";
}

bool ResourceFileSystem::AddArchive(const Containers::String& archivePath) {
    std::lock_guard lock(m_mutex);
    
    // TODO: Implement archive loading
    // For now, just store the path for later resolution
    m_directories.PushBack(archivePath);
    return true;
}

bool ResourceFileSystem::AddDirectory(const Containers::String& directoryPath) {
    std::lock_guard lock(m_mutex);
    m_directories.PushBack(directoryPath);
    return true;
}

void ResourceFileSystem::RemoveArchive(const Containers::String& archivePath) {
    std::lock_guard lock(m_mutex);
    
    // Remove directories - rebuild without the matching one
    Containers::Array<Containers::String> newDirs;
    for (size_t i = 0; i < m_directories.Size(); ++i) {
        if (m_directories[i] != archivePath) {
            newDirs.PushBack(m_directories[i]);
        }
    }
    m_directories = std::move(newDirs);
}

bool ResourceFileSystem::FindResource(const Containers::String& relativePath, Containers::String& outAbsolutePath) const {
    std::lock_guard lock(m_mutex);
    
    if (FindInDirectories(relativePath, outAbsolutePath)) {
        return true;
    }
    
    if (FindInArchives(relativePath, outAbsolutePath)) {
        return true;
    }
    
    return false;
}

Containers::Array<Core::uint8> ResourceFileSystem::ReadResource(const Containers::String& relativePath) const {
    std::lock_guard lock(m_mutex);
    
    Containers::String absolutePath;
    if (!FindResource(relativePath, absolutePath)) {
        return Containers::Array<Core::uint8>();
    }
    
    // Read file
    FILE* file = std::fopen(absolutePath.CStr(), "rb");
    if (!file) {
        return Containers::Array<Core::uint8>();
    }
    
    std::fseek(file, 0, SEEK_END);
    size_t size = std::ftell(file);
    std::fseek(file, 0, SEEK_SET);
    
    Containers::Array<Core::uint8> data;
    data.Resize(size);
    
    size_t readSize = std::fread(data.Data(), 1, size, file);
    std::fclose(file);
    
    if (readSize != size) {
        return Containers::Array<Core::uint8>();
    }
    
    return data;
}

bool ResourceFileSystem::Exists(const Containers::String& relativePath) const {
    Containers::String absolutePath;
    return FindResource(relativePath, absolutePath);
}

bool ResourceFileSystem::GetResourceInfo(const Containers::String& relativePath, ResourceInfo& outInfo) const {
    std::lock_guard lock(m_mutex);
    
    // Check cache first
    auto* cached = m_infoCache.Find(relativePath);
    if (cached != nullptr) {
        outInfo = *cached;
        return true;
    }
    
    Containers::String absolutePath;
    if (!FindResource(relativePath, absolutePath)) {
        return false;
    }
    
    // Get file info
    outInfo.path = relativePath;
    outInfo.inArchive = false;
    
    // TODO: Get actual file size and modification time
    
    m_infoCache.Insert(relativePath, outInfo);
    return true;
}

void ResourceFileSystem::EnumerateResources(const Containers::String& pattern, Containers::Array<ResourceInfo>& outResources) const {
    std::lock_guard lock(m_mutex);
    
    outResources.Clear();
    
    // TODO: Implement pattern matching
}

ResourceFileSystem& ResourceFileSystem::Get() {
    static ResourceFileSystem instance;
    return instance;
}

IArchive* ResourceFileSystem::FindArchive(const Containers::String& relativePath) const {
    for (size_t i = 0; i < m_archives.Size(); ++i) {
        if (m_archives[i]->Exists(relativePath)) {
            return m_archives[i].get();
        }
    }
    return nullptr;
}

bool ResourceFileSystem::FindInDirectories(const Containers::String& relativePath, Containers::String& outAbsolutePath) const {
    // Try root directory first
    if (m_rootPath.Length() > 0) {
        outAbsolutePath = m_rootPath;
        if (!outAbsolutePath.EndsWith("/") && !outAbsolutePath.EndsWith("\\")) {
            outAbsolutePath += "/";
        }
        outAbsolutePath += relativePath;
        
        // Simple check - in real implementation, use OS APIs
        // For now, just return the path
        return true;
    }
    
    // Try each registered directory
    for (size_t i = 0; i < m_directories.Size(); ++i) {
        outAbsolutePath = m_directories[i];
        if (!outAbsolutePath.EndsWith("/") && !outAbsolutePath.EndsWith("\\")) {
            outAbsolutePath += "/";
        }
        outAbsolutePath += relativePath;
        return true;
    }
    
    return false;
}

bool ResourceFileSystem::FindInArchives(const Containers::String& relativePath, Containers::String& outArchivePath) const {
    // Check if resource is in any archive
    IArchive* archive = FindArchive(relativePath);
    if (archive != nullptr) {
        outArchivePath = archive->IsValid() ? "archive://" + relativePath : "";
        return archive->IsValid();
    }
    return false;
}

} // namespace Resources
} // namespace XCEngine