asset.cpp.hpp

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#pragma once
 
// IWYU pragma: private

 
#include "fl/asset/asset.h"
#include "fl/stl/fstream.h"
#include "fl/stl/noexcept.h"
#include "fl/stl/string.h"
#include "fl/stl/string_view.h"
#include "fl/stl/url.h"
#include "fl/stl/vector.h"
#include "platforms/is_platform.h"
 
namespace fl {
 
namespace asset_detail {

struct AssetEntry {
    fl::string path;  
    fl::url url;      
};
 
inline fl::vector<AssetEntry>& registry() FL_NOEXCEPT {
    // Construct-on-first-use avoids static-init ordering issues with the
    // generated asset table (which also uses static init).
    static fl::vector<AssetEntry> s_registry;
    return s_registry;
}

inline fl::url lookup_registry(fl::string_view path) FL_NOEXCEPT {
    auto& r = registry();
    for (fl::size i = 0; i < r.size(); ++i) {
        // Compare as string_view on both sides to avoid any ambiguity in the
        // fl::string / fl::string_view overload resolution.
        fl::string_view candidate(r[i].path.c_str(), r[i].path.size());
        if (candidate == path) {
            return r[i].url;
        }
    }
    return fl::url();
}
 
#if defined(FASTLED_TESTING) || defined(FL_IS_STUB)
inline fl::url resolve_host(fl::string_view path) FL_NOEXCEPT {
    // Try raw file on disk.
    fl::string pathStr(path.data(), path.size());
    {
        fl::ifstream probe(pathStr.c_str(), fl::ios::in | fl::ios::binary);
        if (probe.is_open()) {
            probe.close();
            // Return the path as-is (a relative/absolute filesystem path).
            // fl::url accepts any string; callers on host treat .string() as
            // a local path. This matches the existing AudioUrl test pattern
            // that stores a raw URL string in the url field.
            return fl::url(pathStr);
        }
    }
 
    // Fallback: try <path>.lnk alongside.
    fl::string lnkPath = pathStr;
    lnkPath += ".lnk";
    fl::ifstream lnk(lnkPath.c_str(), fl::ios::in | fl::ios::binary);
    if (!lnk.is_open()) {
        return fl::url();
    }
    // Read entire file. .lnk files are expected to be tiny (URL + a few
    // metadata lines); cap the read at 8 KiB to avoid pathological inputs.
    constexpr fl::size kMaxLnkBytes = 8 * 1024;
    fl::size sz = lnk.size();
    if (sz > kMaxLnkBytes) {
        sz = kMaxLnkBytes;
    }
    fl::string content;
    content.resize(sz);
    if (sz > 0) {
        lnk.read(&content[0], sz);
    }
    lnk.close();
    return parse_lnk(fl::string_view(content.data(), content.size()));
}
#endif
 
} // namespace asset_detail

void register_asset(fl::string_view path, const fl::url& u) FL_NOEXCEPT {
    asset_detail::registry().push_back(
        {fl::string(path.data(), path.size()), u});
}
 
fl::url resolve_asset(const asset_ref& a) FL_NOEXCEPT {
    if (!a) {
        return fl::url();
    }
    const fl::string_view p = a.path();
 
    // 1. Registry always wins. On WASM this is populated by generated code
    //    from the asset scanner; on host/stub tests may populate it manually.
    fl::url fromRegistry = asset_detail::lookup_registry(p);
    if (fromRegistry.isValid()) {
        return fromRegistry;
    }
 
    // 2. Host/stub: fall back to filesystem probe + sibling .lnk.
#if defined(FASTLED_TESTING) || defined(FL_IS_STUB)
    return asset_detail::resolve_host(p);
#else
    // 3. Other platforms (WASM without manifest, ESP32 v1): no fallback.
    //    TODO(#2284): ESP32 LittleFS / SD-card resolution.
    return fl::url();
#endif
}
 
} // namespace fl