<?php
// Sopprime eventuali output di errori (li logghiamo invece di mostrarli)
ob_start();
ini_set('display_errors', 0);
error_reporting(E_ALL);

// Inizia la sessione
session_start();

// Includi PHPSpreadsheet e la classe DBHandler
require_once '../../vendor/autoload.php';
require_once __DIR__ . '/class/db-functions.php';

$response = ['error' => '', 'rows' => [], 'columns' => [], 'template_id' => 0, 'filename' => '', 'apply_routine' => false];

try {
    if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_FILES['excel_file'])) {
        $template_id = isset($_POST['template_id']) ? intval($_POST['template_id']) : 0;
        $header_row = isset($_POST['header_row']) ? intval($_POST['header_row']) : 1;
        $start_column = isset($_POST['start_column']) ? intval($_POST['start_column']) : 1;

        // Debug del template_id ricevuto
        error_log("Received template_id from POST: " . print_r($_POST['template_id'], true));
        error_log("Converted template_id: $template_id");

        $file = $_FILES['excel_file'];
        $fileError = $file['error'];

        if ($fileError === UPLOAD_ERR_OK) {
            // Recupera l'ID dell'utente loggato
            if (!isset($iduserlogin)) {
                $iduserlogin = 1;
                error_log("Warning: iduserlogin non definito, usando 1 come default");
            }

            // Genera il nome del file rinominato
            $timestamp = date('YmdHis');
            $originalFilename = basename($file['name']);
            $newFilename = "{$iduserlogin}-{$timestamp}-{$originalFilename}";
            $importFolder = __DIR__ . '/imported_trf/';
            if (!file_exists($importFolder)) {
                mkdir($importFolder, 0777, true);
            }
            $destination = $importFolder . $newFilename;

            // Sposta il file
            if (!move_uploaded_file($file['tmp_name'], $destination)) {
                throw new Exception("Errore durante lo spostamento del file in $destination");
            }
            error_log("File spostato con successo in: $destination");

            // Connessione al database
            $db = DBHandlerSelect::getInstance();
            $pdo = $db->getConnection();

            // Recupera il mapping da template_mapping
            $stmt = $pdo->prepare("SELECT field_id AS excel_column, field_id AS mysql_column, data_type, is_required, default_value, is_manual FROM template_mapping WHERE template_id = ?");
            $stmt->execute([$template_id]);
            $mappings = $stmt->fetchAll(PDO::FETCH_ASSOC);

            // Also fetch excel_column labels for auto-detect
            $stmtLabels = $pdo->prepare("SELECT excel_column FROM template_mapping WHERE template_id = ? AND is_manual = 0 AND excel_column IS NOT NULL AND excel_column != ''");
            $stmtLabels->execute([$template_id]);
            $templateLabels = array_map('trim', array_map('mb_strtolower', $stmtLabels->fetchAll(PDO::FETCH_COLUMN)));

            // Debug dei mapping
            error_log("Mappings found for template_id $template_id: " . print_r($mappings, true));

            if (empty($mappings)) {
                $response['error'] = "Nessun mapping trovato per il template con ID $template_id";
            } else {
                // Carica il file rinominato con PHPSpreadsheet
                $spreadsheet = \PhpOffice\PhpSpreadsheet\IOFactory::load($destination);
                $worksheet = $spreadsheet->getActiveSheet();
                $highestRow = $worksheet->getHighestRow();
                $highestColumn = $worksheet->getHighestColumn();
                $highestColumnIndex = \PhpOffice\PhpSpreadsheet\Cell\Coordinate::columnIndexFromString($highestColumn);

                // ── Auto-detect header row and start column ──
                // Scan all rows/columns to find the best match against template excel_column labels
                if (!empty($templateLabels)) {
                    $bestRow = max(1, $header_row);
                    $bestCol = max(1, $start_column);
                    $bestScore = 0;
                    $scanLimit = min($highestRow, 50);

                    for ($scanRow = 1; $scanRow <= $scanLimit; $scanRow++) {
                        $score = 0;
                        $firstMatchCol = $highestColumnIndex + 1;
                        for ($col = 1; $col <= $highestColumnIndex; $col++) {
                            $colLetter = \PhpOffice\PhpSpreadsheet\Cell\Coordinate::stringFromColumnIndex($col);
                            $cellVal = $worksheet->getCell($colLetter . $scanRow)->getCalculatedValue();
                            $cellVal = mb_strtolower(trim((string)$cellVal));
                            if ($cellVal !== '' && in_array($cellVal, $templateLabels, true)) {
                                $score++;
                                if ($col < $firstMatchCol) $firstMatchCol = $col;
                            }
                        }
                        if ($score > $bestScore) {
                            $bestScore = $score;
                            $bestRow = $scanRow;
                            $bestCol = $firstMatchCol;
                        }
                    }

                    $header_row = $bestRow;
                    $start_column = $bestCol;
                    error_log("Auto-detected header row: $header_row, start column: $start_column (score: $bestScore/" . count($templateLabels) . ")");
                    $response['auto_header_row'] = $header_row;
                    $response['auto_header_score'] = $bestScore;
                    $response['auto_header_total'] = count($templateLabels);
                }

                $startRow = max(1, $header_row);
                $startColumn = max(1, $start_column);

                // Debug dei parametri
                error_log("Processing - template_id: $template_id, startRow: $startRow, startColumn: $startColumn, highestRow: $highestRow, highestColumn: $highestColumn, highestColumnIndex: $highestColumnIndex");

                // Validazione degli indici
                if ($startRow > $highestRow) {
                    $response['error'] = "La riga di partenza ($startRow) supera il numero totale di righe ($highestRow).";
                } elseif ($startColumn > $highestColumnIndex) {
                    $response['error'] = "La colonna di partenza ($startColumn) supera il numero totale di colonne ($highestColumnIndex).";
                } else {
                    $excelData = [];
                    // Estrai la riga degli header
                    $headerRowData = [];
                    for ($col = $startColumn; $col <= $highestColumnIndex; $col++) {
                        $columnLetter = \PhpOffice\PhpSpreadsheet\Cell\Coordinate::stringFromColumnIndex($col);
                        $cell = $worksheet->getCell($columnLetter . $header_row);
                        $cellValue = $cell ? $cell->getCalculatedValue() : '';
                        $headerRowData[] = $cellValue ?: '';
                    }

                    // Find which header columns are non-empty (these are the "real" columns)
                    $headerFilledIndices = [];
                    foreach ($headerRowData as $idx => $hVal) {
                        if (trim((string)$hVal) !== '') $headerFilledIndices[] = $idx;
                    }
                    // Require at least 2 filled header-columns (or 1 if only 1 exists)
                    $minFilled = max(1, min(2, count($headerFilledIndices)));

                    // Estrai i dati a partire dalla riga successiva, includendo excelrow
                    for ($row = $startRow + 1; $row <= $highestRow; $row++) {
                        $rowData = [];
                        for ($col = $startColumn; $col <= $highestColumnIndex; $col++) {
                            $columnLetter = \PhpOffice\PhpSpreadsheet\Cell\Coordinate::stringFromColumnIndex($col);
                            $cell = $worksheet->getCell($columnLetter . $row);
                            $cellValue = $cell ? $cell->getCalculatedValue() : '';
                            $rowData[] = $cellValue ?: '';
                        }

                        // Count how many "header columns" have data in this row
                        $filledCount = 0;
                        foreach ($headerFilledIndices as $idx) {
                            if (isset($rowData[$idx]) && trim((string)$rowData[$idx]) !== '') {
                                $filledCount++;
                            }
                        }

                        if ($filledCount >= $minFilled) {
                            $excelData[] = ['data' => $rowData, 'excelrow' => $row];
                        }
                    }

                    // Recupera routine dal template
                    $stmt = $pdo->prepare("SELECT idroutine, idclient FROM excel_templates WHERE id = ?");
                    $stmt->execute([$template_id]);
                    $template = $stmt->fetch(PDO::FETCH_ASSOC);

                    if ($template && $template['idroutine']) {
                        $stmtRoutine = $pdo->prepare("SELECT idroutine, name, filename, headerrow, instruction FROM routine WHERE idroutine = ?");
                        $stmtRoutine->execute([$template['idroutine']]);
                        $routineData = $stmtRoutine->fetch(PDO::FETCH_ASSOC);

                        if ($routineData) {
                            $response['apply_routine'] = true;
                            $response['routine_data'] = [
                                'name' => $routineData['name'] ?? 'Routine Sconosciuta',
                                'instruction' => $routineData['instruction'] ?? 'Nessuna descrizione disponibile',
                                'filename' => $routineData['filename'] ?? '',
                                'headerrow' => $routineData['headerrow'] ?? $header_row
                            ];
                            error_log("Routine rilevata per template {$template_id}: " . print_r($routineData, true));
                        } else {
                            error_log("Errore: Nessuna routine trovata per idroutine {$template['idroutine']}");
                        }
                    } else {
                        error_log("Nessuna routine associata al template {$template_id}");
                    }

                    // Aggiungi idclient alla risposta
                    $response['idclient'] = $template['idclient'] ?? null;

                    // Salva i dati in sessione
                    $_SESSION['excel_data'] = $excelData;
                    $_SESSION['template_id'] = $template_id;
                    $_SESSION['headers'] = $headerRowData;
                    $_SESSION['mappings'] = $mappings;

                    // Includi excel_data nella risposta JSON in ogni caso
                    $response['excel_data'] = $excelData;
                    $response['rows'] = array_column($excelData, 'data');
                    $response['columns'] = $headerRowData;
                    $response['template_id'] = $template_id;
                    $response['filename'] = $newFilename;
                }
            }
        } else {
            $response['error'] = "Errore nell'upload del file: Codice errore $fileError.";
        }
    } else {
        $response['error'] = "Richiesta non valida.";
    }
} catch (Exception $e) {
    $response['error'] = "Errore durante il caricamento del file: " . $e->getMessage();
    error_log("Exception in process_import_xls2.php: " . $e->getMessage());
}

// Pulisce qualsiasi output indesiderato
ob_end_clean();

// Invia la risposta JSON
header('Content-Type: application/json');
echo json_encode($response);
exit;