ANSCORE/modules/ANSLPR/ANSLPR_OCR.cpp

#include "ANSLPR_OCR.h"
#include "ANSRTYOLO.h"
#include "ANSONNXYOLO.h"
#include "ANSOnnxOCR.h"
#include "ANSOCRBase.h"

#include <json.hpp>
#include <algorithm>
#include <chrono>

// ---------------------------------------------------------------------------
// SEH wrapper for loading ONNX models — identical to the one in ANSLPR_OD.cpp
// ---------------------------------------------------------------------------
static void WriteEventLog(const char* message, WORD eventType = EVENTLOG_INFORMATION_TYPE) {
	static HANDLE hEventLog = RegisterEventSourceA(NULL, "ANSLogger");
	if (hEventLog) {
		const char* msgs[1] = { message };
		ReportEventA(hEventLog, eventType, 0, 0, NULL, 1, 0, msgs, NULL);
	}
	OutputDebugStringA(message);
	OutputDebugStringA("\n");
}

// ---------------------------------------------------------------------------
// SEH wrapper for loading ANSRTYOLO (TensorRT) models — used when NVIDIA GPU
// is detected.  Falls back to ANSONNXYOLO if TRT fails.
// ---------------------------------------------------------------------------
struct LoadRtParams_OCR {
	const std::string*                      licenseKey;
	ANSCENTER::ModelConfig*                 config;
	const std::string*                      modelFolder;
	const char*                             modelName;
	const char*                             classFile;
	std::string*                            labels;
	std::unique_ptr<ANSCENTER::ANSODBase>*  detector;
	bool                                    enableTracker;
	bool                                    disableStabilization;
};

static bool LoadRtModel_OCR_Impl(const LoadRtParams_OCR& p) {
	try {
		auto rtyolo = std::make_unique<ANSCENTER::ANSRTYOLO>();
		bool ok = rtyolo->LoadModelFromFolder(
			*p.licenseKey, *p.config, p.modelName, p.classFile,
			*p.modelFolder, *p.labels);
		if (!ok) {
			return false;
		}
		if (p.enableTracker) {
			rtyolo->SetTracker(ANSCENTER::TrackerType::BYTETRACK, true);
		} else {
			rtyolo->SetTracker(ANSCENTER::TrackerType::BYTETRACK, false);
		}
		if (p.disableStabilization) {
			rtyolo->SetStabilization(false);
		}
		*p.detector = std::move(rtyolo);
		return true;
	}
	catch (...) {
		p.detector->reset();
		return false;
	}
}

static bool LoadRtModel_OCR_SEH(const LoadRtParams_OCR& p, DWORD* outCode) {
	*outCode = 0;
	__try {
		return LoadRtModel_OCR_Impl(p);
	}
	__except (EXCEPTION_EXECUTE_HANDLER) {
		*outCode = GetExceptionCode();
		return false;
	}
}

struct LoadOnnxParams_OCR {
	const std::string*                      licenseKey;
	ANSCENTER::ModelConfig*                 config;
	const std::string*                      modelFolder;
	const char*                             modelName;
	const char*                             classFile;
	std::string*                            labels;
	std::unique_ptr<ANSCENTER::ANSODBase>*  detector;
	bool                                    enableTracker;
	bool                                    disableStabilization;
};

static bool LoadOnnxModel_OCR_Impl(const LoadOnnxParams_OCR& p) {
	try {
		auto onnxyolo = std::make_unique<ANSCENTER::ANSONNXYOLO>();
		bool ok = onnxyolo->LoadModelFromFolder(
			*p.licenseKey, *p.config, p.modelName, p.classFile,
			*p.modelFolder, *p.labels);
		if (!ok) {
			return false;
		}
		if (p.enableTracker) {
			onnxyolo->SetTracker(ANSCENTER::TrackerType::BYTETRACK, true);
		} else {
			onnxyolo->SetTracker(ANSCENTER::TrackerType::BYTETRACK, false);
		}
		if (p.disableStabilization) {
			onnxyolo->SetStabilization(false);
		}
		*p.detector = std::move(onnxyolo);
		return true;
	}
	catch (...) {
		p.detector->reset();
		return false;
	}
}

static bool LoadOnnxModel_OCR_SEH(const LoadOnnxParams_OCR& p, DWORD* outCode) {
	*outCode = 0;
	__try {
		return LoadOnnxModel_OCR_Impl(p);
	}
	__except (EXCEPTION_EXECUTE_HANDLER) {
		*outCode = GetExceptionCode();
		return false;
	}
}

namespace ANSCENTER
{
	ANSALPR_OCR::ANSALPR_OCR() {
		engineType = EngineType::CPU;
	}

	ANSALPR_OCR::~ANSALPR_OCR() {
		try {
			Destroy();
		}
		catch (...) {}
	}

	bool ANSALPR_OCR::Initialize(const std::string& licenseKey, const std::string& modelZipFilePath,
		const std::string& modelZipPassword, double detectorThreshold, double ocrThreshold, double colourThreshold) {
		std::lock_guard<std::recursive_mutex> lock(_mutex);
		try {
			_licenseKey = licenseKey;
			_licenseValid = false;
			_detectorThreshold = detectorThreshold;
			_ocrThreshold = ocrThreshold;
			_colorThreshold = colourThreshold;
			_country = Country::JAPAN; // Default to JAPAN for OCR-based ALPR
			CheckLicense();
			if (!_licenseValid) {
				this->_logger.LogError("ANSALPR_OCR::Initialize", "License is not valid.", __FILE__, __LINE__);
				return false;
			}

			// Extract model folder
			if (!FileExist(modelZipFilePath)) {
				this->_logger.LogFatal("ANSALPR_OCR::Initialize", "Model zip file does not exist: " + modelZipFilePath, __FILE__, __LINE__);
				return false;
			}
			this->_logger.LogInfo("ANSALPR_OCR::Initialize", "Model zip file found: " + modelZipFilePath, __FILE__, __LINE__);

			// Unzip model zip file
			std::vector<std::string> passwordArray;
			if (!modelZipPassword.empty()) passwordArray.push_back(modelZipPassword);
			passwordArray.push_back("AnsDemoModels20@!");
			passwordArray.push_back("Sh7O7nUe7vJ/417W0gWX+dSdfcP9hUqtf/fEqJGqxYL3PedvHubJag==");
			passwordArray.push_back("3LHxGrjQ7kKDJBD9MX86H96mtKLJaZcTYXrYRdQgW8BKGt7enZHYMg==");
			std::string modelName = GetFileNameWithoutExtension(modelZipFilePath);

			for (size_t i = 0; i < passwordArray.size(); i++) {
				if (ExtractPasswordProtectedZip(modelZipFilePath, passwordArray[i], modelName, _modelFolder, false))
					break;
			}

			if (!FolderExist(_modelFolder)) {
				this->_logger.LogError("ANSALPR_OCR::Initialize", "Output model folder does not exist: " + _modelFolder, __FILE__, __LINE__);
				return false;
			}

			// Check country from country.txt
			std::string countryFile = CreateFilePath(_modelFolder, "country.txt");
			if (FileExist(countryFile)) {
				std::ifstream infile(countryFile);
				std::string countryStr;
				std::getline(infile, countryStr);
				infile.close();
				if (countryStr == "0")      _country = Country::VIETNAM;
				else if (countryStr == "1")  _country = Country::CHINA;
				else if (countryStr == "2")  _country = Country::AUSTRALIA;
				else if (countryStr == "3")  _country = Country::USA;
				else if (countryStr == "4")  _country = Country::INDONESIA;
				else if (countryStr == "5")  _country = Country::JAPAN;
				else                         _country = Country::JAPAN; // Default for OCR mode
			}

			// Store the original model zip path — the OCR models (ansocrdec.onnx,
			// ansocrcls.onnx, ansocrrec.onnx, dict_ch.txt) are bundled inside the
			// same ALPR model zip, so we reuse it for ANSONNXOCR initialization.
			_modelZipFilePath = modelZipFilePath;

			// Initialize ALPRChecker
			alprChecker.Init(MAX_ALPR_FRAME);

			_lpColourModelConfig.detectionScoreThreshold = _colorThreshold;
			_lpdmodelConfig.detectionScoreThreshold = _detectorThreshold;

			return true;
		}
		catch (std::exception& e) {
			this->_logger.LogFatal("ANSALPR_OCR::Initialize", e.what(), __FILE__, __LINE__);
			return false;
		}
	}

	bool ANSALPR_OCR::LoadEngine() {
		std::lock_guard<std::recursive_mutex> lock(_mutex);
		try {
			WriteEventLog("ANSALPR_OCR::LoadEngine: Step 1 - Starting engine load");
			this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 1: Starting engine load", __FILE__, __LINE__);

			// Detect hardware
			_lpdmodelConfig.detectionScoreThreshold = _detectorThreshold;
			_lpColourModelConfig.detectionScoreThreshold = _colorThreshold;

			if (_lpdmodelConfig.detectionScoreThreshold < 0.25) _lpdmodelConfig.detectionScoreThreshold = 0.25;
			if (_lpdmodelConfig.detectionScoreThreshold > 0.95) _lpdmodelConfig.detectionScoreThreshold = 0.95;

			engineType = ANSLicenseHelper::CheckHardwareInformation();
			this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Detected engine type: " + std::to_string(static_cast<int>(engineType)), __FILE__, __LINE__);

			float confThreshold = 0.5f;
			float MNSThreshold = 0.5f;
			_lpdmodelConfig.modelConfThreshold = confThreshold;
			_lpdmodelConfig.modelMNSThreshold = MNSThreshold;
			_lpColourModelConfig.modelConfThreshold = confThreshold;
			_lpColourModelConfig.modelMNSThreshold = MNSThreshold;

			std::string lprModel = CreateFilePath(_modelFolder, "lpd.onnx");
			std::string colorModel = CreateFilePath(_modelFolder, "lpc.onnx");

			bool valid = false;

			// ── Step 2: Load LP detector ─────────────────────────────────
			if (FileExist(lprModel)) {
				// Try TensorRT (ANSRTYOLO) when NVIDIA GPU is detected
				if (engineType == EngineType::NVIDIA_GPU) {
					WriteEventLog("ANSALPR_OCR::LoadEngine: Step 2 - Loading LP detector with TensorRT");
					this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 2: Loading LP detector with TensorRT", __FILE__, __LINE__);
					_lpdmodelConfig.detectionType = DetectionType::DETECTION;
					_lpdmodelConfig.modelType     = ModelType::RTYOLO;
					std::string _lprClasses;
					{
						LoadRtParams_OCR p{};
						p.licenseKey           = &_licenseKey;
						p.config               = &_lpdmodelConfig;
						p.modelFolder          = &_modelFolder;
						p.modelName            = "lpd";
						p.classFile            = "lpd.names";
						p.labels               = &_lprClasses;
						p.detector             = &_lpDetector;
						p.enableTracker        = true;
						p.disableStabilization = true;

						DWORD sehCode = 0;
						bool lpSuccess = LoadRtModel_OCR_SEH(p, &sehCode);
						if (sehCode != 0) {
							char buf[256];
							snprintf(buf, sizeof(buf),
								"ANSALPR_OCR::LoadEngine: Step 2 LPD TRT SEH exception 0x%08X — falling back to ONNX Runtime", sehCode);
							WriteEventLog(buf, EVENTLOG_ERROR_TYPE);
							this->_logger.LogError("ANSALPR_OCR::LoadEngine",
								"Step 2: LP detector TensorRT crashed (SEH). Falling back to ONNX Runtime.", __FILE__, __LINE__);
							if (_lpDetector) _lpDetector.reset();
						}
						else if (!lpSuccess) {
							this->_logger.LogError("ANSALPR_OCR::LoadEngine",
								"Failed to load LP detector (TensorRT). Falling back to ONNX Runtime.", __FILE__, __LINE__);
							if (_lpDetector) _lpDetector.reset();
						}
					}
				}

				// Fallback to ONNX Runtime (ANSONNXYOLO) if TRT was not attempted or failed
				if (!_lpDetector) {
					WriteEventLog("ANSALPR_OCR::LoadEngine: Step 2 - Loading LP detector with ONNX Runtime");
					this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 2: Loading LP detector with ONNX Runtime", __FILE__, __LINE__);
					_lpdmodelConfig.detectionType = DetectionType::DETECTION;
					_lpdmodelConfig.modelType     = ModelType::ONNXYOLO;
					std::string _lprClasses;
					{
						LoadOnnxParams_OCR p{};
						p.licenseKey           = &_licenseKey;
						p.config               = &_lpdmodelConfig;
						p.modelFolder          = &_modelFolder;
						p.modelName            = "lpd";
						p.classFile            = "lpd.names";
						p.labels               = &_lprClasses;
						p.detector             = &_lpDetector;
						p.enableTracker        = true;
						p.disableStabilization = true;

						DWORD sehCode = 0;
						bool lpSuccess = LoadOnnxModel_OCR_SEH(p, &sehCode);
						if (sehCode != 0) {
							char buf[256];
							snprintf(buf, sizeof(buf),
								"ANSALPR_OCR::LoadEngine: Step 2 LPD SEH exception 0x%08X — LP detector disabled", sehCode);
							WriteEventLog(buf, EVENTLOG_ERROR_TYPE);
							this->_logger.LogFatal("ANSALPR_OCR::LoadEngine",
								"Step 2: LP detector crashed (SEH). LP detector disabled.", __FILE__, __LINE__);
							if (_lpDetector) _lpDetector.reset();
						}
						else if (!lpSuccess) {
							this->_logger.LogError("ANSALPR_OCR::LoadEngine",
								"Failed to load LP detector (ONNX Runtime).", __FILE__, __LINE__);
							if (_lpDetector) _lpDetector.reset();
						}
					}
				}
			}

			if (!_lpDetector) {
				this->_logger.LogFatal("ANSALPR_OCR::LoadEngine", "LP detector failed to load. Cannot proceed.", __FILE__, __LINE__);
				_isInitialized = false;
				return false;
			}

			// ── Step 3: Load OCR engine (ANSONNXOCR) ─────────────────────
			// The OCR models (ansocrdec.onnx, ansocrcls.onnx, ansocrrec.onnx,
			// dict_ch.txt) are bundled inside the same ALPR model zip, so we
			// pass the original ALPR zip path to ANSONNXOCR::Initialize.
			// ANSOCRBase::Initialize will extract it (no-op if already done)
			// and discover the OCR model files in the extracted folder.
			WriteEventLog("ANSALPR_OCR::LoadEngine: Step 3 - Loading OCR engine (ANSONNXOCR)");
			this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 3: Loading OCR engine (ANSONNXOCR)", __FILE__, __LINE__);

			// Verify OCR model files exist in the already-extracted folder
			std::string ocrDetModel = CreateFilePath(_modelFolder, "ansocrdec.onnx");
			std::string ocrRecModel = CreateFilePath(_modelFolder, "ansocrrec.onnx");
			if (!FileExist(ocrDetModel) || !FileExist(ocrRecModel)) {
				this->_logger.LogFatal("ANSALPR_OCR::LoadEngine",
					"OCR model files not found in model folder: " + _modelFolder +
					" (expected ansocrdec.onnx, ansocrrec.onnx)", __FILE__, __LINE__);
				_isInitialized = false;
				return false;
			}

			_ocrEngine = std::make_unique<ANSONNXOCR>();

			// Determine OCR language based on country
			OCRLanguage ocrLang = OCRLanguage::ENGLISH;
			switch (_country) {
				case Country::JAPAN:     ocrLang = OCRLanguage::JAPANESE; break;
				case Country::CHINA:     ocrLang = OCRLanguage::CHINESE;  break;
				case Country::VIETNAM:   ocrLang = OCRLanguage::ENGLISH;  break;
				case Country::AUSTRALIA: ocrLang = OCRLanguage::ENGLISH;  break;
				case Country::USA:       ocrLang = OCRLanguage::ENGLISH;  break;
				case Country::INDONESIA: ocrLang = OCRLanguage::ENGLISH;  break;
				default:                 ocrLang = OCRLanguage::ENGLISH;  break;
			}

			OCRModelConfig ocrModelConfig;
			ocrModelConfig.ocrLanguage = ocrLang;
			ocrModelConfig.useDetector = true;
			ocrModelConfig.useRecognizer = true;
			ocrModelConfig.useCLS = true;
			ocrModelConfig.useLayout = false;
			ocrModelConfig.useTable = false;
			ocrModelConfig.useTensorRT = false;
			ocrModelConfig.enableMKLDNN = false;
			ocrModelConfig.useDilation = true;
			ocrModelConfig.useAngleCLS = false;
			ocrModelConfig.gpuId = 0;
			ocrModelConfig.detectionDBThreshold = 0.5;
			ocrModelConfig.detectionBoxThreshold = 0.3;
			ocrModelConfig.detectionDBUnclipRatio = 1.2;
			ocrModelConfig.clsThreshold = 0.9;
			ocrModelConfig.limitSideLen = 2560;

			// Pass the original ALPR model zip path — ANSOCRBase::Initialize
			// will extract it to the same folder (already done, so extraction
			// is a no-op) and set up ansocrdec.onnx / ansocrcls.onnx /
			// ansocrrec.onnx / dict_ch.txt paths automatically.
			bool ocrSuccess = _ocrEngine->Initialize(_licenseKey, ocrModelConfig, _modelZipFilePath, "", 0);
			if (!ocrSuccess) {
				this->_logger.LogFatal("ANSALPR_OCR::LoadEngine", "Failed to initialize OCR engine (ANSONNXOCR).", __FILE__, __LINE__);
				_ocrEngine.reset();
				_isInitialized = false;
				return false;
			}

			// Set ALPR mode and country on the OCR engine
			_ocrEngine->SetOCRMode(OCRMode::OCR_ALPR);
			_ocrEngine->SetCountry(_country);

			this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 3: OCR engine loaded successfully.", __FILE__, __LINE__);

			// ── Step 4: Load colour classifier (optional) ────────────────
			if (FileExist(colorModel) && (_lpColourModelConfig.detectionScoreThreshold > 0)) {
				// Try TensorRT (ANSRTYOLO) when NVIDIA GPU is detected
				if (engineType == EngineType::NVIDIA_GPU) {
					WriteEventLog("ANSALPR_OCR::LoadEngine: Step 4 - Loading colour classifier with TensorRT");
					this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 4: Loading colour classifier with TensorRT", __FILE__, __LINE__);
					_lpColourModelConfig.detectionType = DetectionType::CLASSIFICATION;
					_lpColourModelConfig.modelType     = ModelType::RTYOLO;
					{
						LoadRtParams_OCR p{};
						p.licenseKey           = &_licenseKey;
						p.config               = &_lpColourModelConfig;
						p.modelFolder          = &_modelFolder;
						p.modelName            = "lpc";
						p.classFile            = "lpc.names";
						p.labels               = &_lpColourLabels;
						p.detector             = &_lpColourDetector;
						p.enableTracker        = false;
						p.disableStabilization = false;

						DWORD sehCode = 0;
						bool colourSuccess = LoadRtModel_OCR_SEH(p, &sehCode);
						if (sehCode != 0) {
							char buf[256];
							snprintf(buf, sizeof(buf),
								"ANSALPR_OCR::LoadEngine: Step 4 LPC TRT SEH exception 0x%08X — falling back to ONNX Runtime", sehCode);
							WriteEventLog(buf, EVENTLOG_ERROR_TYPE);
							this->_logger.LogError("ANSALPR_OCR::LoadEngine",
								"Step 4: Colour classifier TensorRT crashed (SEH). Falling back to ONNX Runtime.", __FILE__, __LINE__);
							if (_lpColourDetector) _lpColourDetector.reset();
						}
						else if (!colourSuccess) {
							this->_logger.LogError("ANSALPR_OCR::LoadEngine",
								"Failed to load colour classifier (TensorRT). Falling back to ONNX Runtime.", __FILE__, __LINE__);
							if (_lpColourDetector) _lpColourDetector.reset();
						}
					}
				}

				// Fallback to ONNX Runtime (ANSONNXYOLO) if TRT was not attempted or failed
				if (!_lpColourDetector) {
					WriteEventLog("ANSALPR_OCR::LoadEngine: Step 4 - Loading colour classifier with ONNX Runtime");
					this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 4: Loading colour classifier with ONNX Runtime", __FILE__, __LINE__);
					_lpColourModelConfig.detectionType = DetectionType::CLASSIFICATION;
					_lpColourModelConfig.modelType     = ModelType::ONNXYOLO;
					{
						LoadOnnxParams_OCR p{};
						p.licenseKey           = &_licenseKey;
						p.config               = &_lpColourModelConfig;
						p.modelFolder          = &_modelFolder;
						p.modelName            = "lpc";
						p.classFile            = "lpc.names";
						p.labels               = &_lpColourLabels;
						p.detector             = &_lpColourDetector;
						p.enableTracker        = false;
						p.disableStabilization = false;

						DWORD sehCode = 0;
						bool colourSuccess = LoadOnnxModel_OCR_SEH(p, &sehCode);
						if (sehCode != 0) {
							char buf[256];
							snprintf(buf, sizeof(buf),
								"ANSALPR_OCR::LoadEngine: Step 4 LPC SEH exception 0x%08X — colour detection disabled", sehCode);
							WriteEventLog(buf, EVENTLOG_ERROR_TYPE);
							this->_logger.LogError("ANSALPR_OCR::LoadEngine",
								"Step 4: Colour classifier crashed. Colour detection disabled.", __FILE__, __LINE__);
							if (_lpColourDetector) _lpColourDetector.reset();
						}
						else if (!colourSuccess) {
							this->_logger.LogError("ANSALPR_OCR::LoadEngine",
								"Failed to load colour detector (ONNX Runtime). Colour detection disabled.", __FILE__, __LINE__);
							if (_lpColourDetector) _lpColourDetector.reset();
						}
					}
				}
			}

			valid = true;
			_isInitialized = valid;
			WriteEventLog(("ANSALPR_OCR::LoadEngine: Step 5 - Engine load complete. Valid = " + std::to_string(valid)).c_str());
			this->_logger.LogInfo("ANSALPR_OCR::LoadEngine", "Step 5: Engine load complete. Valid = " + std::to_string(valid), __FILE__, __LINE__);
			return valid;
		}
		catch (std::exception& e) {
			WriteEventLog(("ANSALPR_OCR::LoadEngine: C++ exception: " + std::string(e.what())).c_str(), EVENTLOG_ERROR_TYPE);
			this->_logger.LogFatal("ANSALPR_OCR::LoadEngine", std::string("C++ exception: ") + e.what(), __FILE__, __LINE__);
			_isInitialized = false;
			return false;
		}
		catch (...) {
			WriteEventLog("ANSALPR_OCR::LoadEngine: Unknown exception", EVENTLOG_ERROR_TYPE);
			this->_logger.LogFatal("ANSALPR_OCR::LoadEngine", "Unknown exception", __FILE__, __LINE__);
			_isInitialized = false;
			return false;
		}
	}

	// ── Colour detection (same pattern as ANSALPR_OD) ────────────────────
	std::string ANSALPR_OCR::DetectLPColourDetector(const cv::Mat& lprROI, const std::string& cameraId) {
		if (_lpColourModelConfig.detectionScoreThreshold <= 0.0f) return {};
		if (!_lpColourDetector) return {};
		if (lprROI.empty()) return {};

		try {
			std::vector<Object> colourOutputs = _lpColourDetector->RunInference(lprROI, cameraId);
			if (colourOutputs.empty()) return {};

			const auto& bestDetection = *std::max_element(
				colourOutputs.begin(), colourOutputs.end(),
				[](const Object& a, const Object& b) { return a.confidence < b.confidence; }
			);
			return bestDetection.className;
		}
		catch (const std::exception& e) {
			this->_logger.LogFatal("ANSALPR_OCR::DetectLPColourDetector", e.what(), __FILE__, __LINE__);
			return {};
		}
	}

	std::string ANSALPR_OCR::DetectLPColourCached(const cv::Mat& lprROI, const std::string& cameraId, const std::string& plateText) {
		if (plateText.empty()) {
			return DetectLPColourDetector(lprROI, cameraId);
		}

		// Check cache first
		{
			std::lock_guard<std::mutex> cacheLock(_colourCacheMutex);
			auto it = _colourCache.find(plateText);
			if (it != _colourCache.end()) {
				it->second.hitCount++;
				return it->second.colour;
			}
		}

		// Cache miss — run classifier
		std::string colour = DetectLPColourDetector(lprROI, cameraId);

		if (!colour.empty()) {
			std::lock_guard<std::mutex> cacheLock(_colourCacheMutex);
			if (_colourCache.size() >= COLOUR_CACHE_MAX_SIZE) {
				_colourCache.clear();
			}
			_colourCache[plateText] = { colour, 0 };
		}

		return colour;
	}

	// ── OCR on a single plate ROI ────────────────────────────────────────
	// Returns the plate text via the out-parameter and populates alprExtraInfo
	// with the structured ALPR JSON (zone parts) when ALPR mode is active.
	std::string ANSALPR_OCR::RunOCROnPlate(const cv::Mat& plateROI, const std::string& cameraId) {
		if (!_ocrEngine || plateROI.empty()) return "";
		if (plateROI.cols < 10 || plateROI.rows < 10) return "";

		try {
			// Run the full ANSONNXOCR pipeline on the cropped plate image
			std::vector<OCRObject> ocrResults = _ocrEngine->RunInference(plateROI, cameraId);

			if (ocrResults.empty()) return "";

			// If ALPR mode is active and we have plate formats, use the
			// structured ALPR post-processing to get correct zone ordering
			// (e.g. "品川 302 ま 93-15" instead of "品川30293-15ま")
			const auto& alprFormats = _ocrEngine->GetALPRFormats();
			if (_ocrEngine->GetOCRMode() == OCRMode::OCR_ALPR && !alprFormats.empty()) {
				auto alprResults = ANSOCRUtility::ALPRPostProcessing(
					ocrResults, alprFormats,
					plateROI.cols, plateROI.rows,
					_ocrEngine.get(), plateROI);

				if (!alprResults.empty()) {
					return alprResults[0].fullPlateText;
				}
			}

			// Fallback: simple concatenation sorted by Y then X
			std::sort(ocrResults.begin(), ocrResults.end(),
				[](const OCRObject& a, const OCRObject& b) {
					int rowThreshold = std::min(a.box.height, b.box.height) / 2;
					if (std::abs(a.box.y - b.box.y) > rowThreshold) {
						return a.box.y < b.box.y;
					}
					return a.box.x < b.box.x;
				}
			);

			std::string fullText;
			for (const auto& obj : ocrResults) {
				if (!obj.className.empty()) {
					fullText += obj.className;
				}
			}

			return fullText;
		}
		catch (const std::exception& e) {
			this->_logger.LogError("ANSALPR_OCR::RunOCROnPlate", e.what(), __FILE__, __LINE__);
			return "";
		}
	}

	// ── Main inference pipeline ──────────────────────────────────────────
	std::vector<Object> ANSALPR_OCR::RunInference(const cv::Mat& input, const std::string& cameraId) {
		if (!_licenseValid) {
			this->_logger.LogError("ANSALPR_OCR::RunInference", "Invalid license", __FILE__, __LINE__);
			return {};
		}
		if (!_isInitialized) {
			this->_logger.LogError("ANSALPR_OCR::RunInference", "Model is not initialized", __FILE__, __LINE__);
			return {};
		}
		if (input.empty() || input.cols < 5 || input.rows < 5) {
			this->_logger.LogError("ANSALPR_OCR::RunInference", "Input image is empty or too small", __FILE__, __LINE__);
			return {};
		}
		if (!_lpDetector) {
			this->_logger.LogFatal("ANSALPR_OCR::RunInference", "_lpDetector is null", __FILE__, __LINE__);
			return {};
		}
		if (!_ocrEngine) {
			this->_logger.LogFatal("ANSALPR_OCR::RunInference", "_ocrEngine is null", __FILE__, __LINE__);
			return {};
		}

		try {
			// Convert grayscale to BGR if necessary
			cv::Mat localFrame;
			if (input.channels() == 1) {
				cv::cvtColor(input, localFrame, cv::COLOR_GRAY2BGR);
			}
			const cv::Mat& frame = (input.channels() == 1) ? localFrame : input;

			const int frameWidth = frame.cols;
			const int frameHeight = frame.rows;

			// Step 1: Detect license plates
			std::vector<Object> lprOutput = _lpDetector->RunInference(frame, cameraId);

			if (lprOutput.empty()) {
				return {};
			}

			std::vector<Object> output;
			output.reserve(lprOutput.size());

			for (auto& lprObject : lprOutput) {
				const cv::Rect& box = lprObject.box;

				// Calculate safe cropped region
				const int x1 = std::max(0, box.x);
				const int y1 = std::max(0, box.y);
				const int width = std::min(frameWidth - x1, box.width);
				const int height = std::min(frameHeight - y1, box.height);

				if (width <= 0 || height <= 0) continue;

				cv::Rect lprPos(x1, y1, width, height);
				cv::Mat plateROI = frame(lprPos);

				// Step 2: Run OCR on the detected plate
				std::string ocrText = RunOCROnPlate(plateROI, cameraId);

				if (ocrText.empty()) continue;

				lprObject.cameraId = cameraId;

				// Use ALPRChecker for text stabilization if enabled
				if (_enableALPRChecker) {
					lprObject.className = alprChecker.checkPlateByTrackId(cameraId, ocrText, lprObject.trackId);
				} else {
					lprObject.className = ocrText;
				}

				if (lprObject.className.empty()) continue;

				// Step 3: Colour detection (optional)
				std::string colour = DetectLPColourCached(plateROI, cameraId, lprObject.className);
				if (!colour.empty()) {
					lprObject.extraInfo = "color:" + colour;
				}

				output.push_back(std::move(lprObject));
			}

			return output;
		}
		catch (const cv::Exception& e) {
			this->_logger.LogFatal("ANSALPR_OCR::RunInference", std::string("OpenCV Exception: ") + e.what(), __FILE__, __LINE__);
		}
		catch (const std::exception& e) {
			this->_logger.LogFatal("ANSALPR_OCR::RunInference", e.what(), __FILE__, __LINE__);
		}
		catch (...) {
			this->_logger.LogFatal("ANSALPR_OCR::RunInference", "Unknown exception occurred", __FILE__, __LINE__);
		}

		return {};
	}

	// ── Inference wrappers ───────────────────────────────────────────────
	bool ANSALPR_OCR::Inference(const cv::Mat& input, std::string& lprResult) {
		if (input.empty()) return false;
		if (input.cols < 5 || input.rows < 5) return false;
		return Inference(input, lprResult, "CustomCam");
	}

	bool ANSALPR_OCR::Inference(const cv::Mat& input, std::string& lprResult, const std::string& cameraId) {
		if (input.empty()) return false;
		if (input.cols < 5 || input.rows < 5) return false;

		try {
			std::vector<Object> results = RunInference(input, cameraId);
			lprResult = VectorDetectionToJsonString(results);
			return !results.empty();
		}
		catch (...) {
			return false;
		}
	}

	bool ANSALPR_OCR::Inference(const cv::Mat& input, const std::vector<cv::Rect>& Bbox, std::string& lprResult) {
		return Inference(input, Bbox, lprResult, "CustomCam");
	}

	bool ANSALPR_OCR::Inference(const cv::Mat& input, const std::vector<cv::Rect>& Bbox, std::string& lprResult, const std::string& cameraId) {
		if (input.empty()) return false;
		if (input.cols < 5 || input.rows < 5) return false;

		try {
			if (Bbox.empty()) {
				return Inference(input, lprResult, cameraId);
			}

			// For cropped images, run OCR on each bounding box
			std::vector<Object> allResults;
			cv::Mat frame;
			if (input.channels() == 1) {
				cv::cvtColor(input, frame, cv::COLOR_GRAY2BGR);
			} else {
				frame = input;
			}

			for (const auto& bbox : Bbox) {
				int x1 = std::max(0, bbox.x);
				int y1 = std::max(0, bbox.y);
				int w = std::min(frame.cols - x1, bbox.width);
				int h = std::min(frame.rows - y1, bbox.height);

				if (w < 5 || h < 5) continue;

				cv::Rect safeRect(x1, y1, w, h);
				cv::Mat cropped = frame(safeRect);

				std::vector<Object> results = RunInference(cropped, cameraId);

				// Adjust bounding boxes back to full image coordinates
				for (auto& obj : results) {
					obj.box.x += x1;
					obj.box.y += y1;
					allResults.push_back(std::move(obj));
				}
			}

			lprResult = VectorDetectionToJsonString(allResults);
			return !allResults.empty();
		}
		catch (...) {
			return false;
		}
	}

	void ANSALPR_OCR::SetCountry(Country country) {
		_country = country;
		if (_ocrEngine) {
			_ocrEngine->SetCountry(country);
		}
	}

	bool ANSALPR_OCR::Destroy() {
		try {
			if (_lpDetector) {
				_lpDetector->Destroy();
				_lpDetector.reset();
			}
			if (_lpColourDetector) {
				_lpColourDetector->Destroy();
				_lpColourDetector.reset();
			}
			if (_ocrEngine) {
				_ocrEngine->Destroy();
				_ocrEngine.reset();
			}
			_isInitialized = false;
			return true;
		}
		catch (std::exception& e) {
			this->_logger.LogFatal("ANSALPR_OCR::Destroy", e.what(), __FILE__, __LINE__);
			return false;
		}
	}

} // namespace ANSCENTER