<?php

require_once __DIR__ . '/auth_check.php';

mnt_require_permission('maintenance.manage');

/**
 * Registers (or updates) one intervention against a maintenance and
 * recomputes the maintenance schedule.
 *
 * The operator signature arrives as a data URL from the tablet canvas and
 * is stored as a PNG in attachments/.
 */
try {
    $pdo = mnt_pdo();

    $id             = (int)($_POST['id'] ?? 0);
    $maintenanceId  = (int)($_POST['maintenance_id'] ?? 0);
    $performedAt    = trim((string)($_POST['performed_at'] ?? ''));
    $status         = (string)($_POST['status'] ?? 'completed');
    $result         = trim((string)($_POST['result'] ?? ''));
    $notes          = trim((string)($_POST['notes'] ?? ''));
    $materials      = trim((string)($_POST['materials'] ?? ''));
    $operatorId     = (int)($_POST['operator_employee_id'] ?? 0);
    $operatorName   = trim((string)($_POST['operator_name'] ?? ''));
    $supplierId     = (int)($_POST['supplier_id'] ?? 0);
    $signatureData  = (string)($_POST['signature'] ?? '');
    $clearSignature = !empty($_POST['clear_signature']);

    if ($performedAt === '' || !preg_match('/^\d{4}-\d{2}-\d{2}$/', $performedAt)) {
        mnt_json_fail('La data dell\'intervento è obbligatoria.');
    }

    $validStatuses = mnt_lookup($pdo, 'maint_status', ['planned' => '', 'in_progress' => '', 'completed' => '']);
    if (!array_key_exists($status, $validStatuses)) {
        mnt_json_fail('Stato intervento non valido.');
    }

    $validResults = mnt_lookup($pdo, 'maint_result', []);
    if ($result !== '' && $validResults && !array_key_exists($result, $validResults)) {
        mnt_json_fail('Esito intervento non valido.');
    }

    // Existing row: maintenance is taken from the record, not from the client
    if ($id > 0) {
        $stmt = $pdo->prepare("SELECT * FROM maint_interventions WHERE id = ?");
        $stmt->execute([$id]);
        $existing = $stmt->fetch(PDO::FETCH_ASSOC);

        if (!$existing) {
            mnt_json_fail('Intervento non trovato.');
        }

        $maintenanceId = (int)$existing['maintenance_id'];
        $equipmentId = (int)$existing['equipment_id'];
        $signaturePath = $existing['signature_path'];
    } else {
        $stmt = $pdo->prepare("SELECT equipment_id FROM maint_maintenances WHERE id = ?");
        $stmt->execute([$maintenanceId]);
        $equipmentId = (int)$stmt->fetchColumn();

        if (!$equipmentId) {
            mnt_json_fail('Manutenzione non trovata.');
        }

        $signaturePath = null;
    }

    // Signature handling
    if ($clearSignature && $signaturePath) {
        mnt_delete_stored_file((string)$signaturePath);
        $signaturePath = null;
    }

    if ($signatureData !== '' && preg_match('#^data:image/png;base64,#', $signatureData)) {
        $binary = base64_decode(substr($signatureData, strlen('data:image/png;base64,')), true);

        if ($binary === false || strlen($binary) > 2 * 1024 * 1024) {
            mnt_json_fail('Firma non valida.');
        }

        $uploadDir = __DIR__ . '/../attachments/';
        if (!is_dir($uploadDir) && !mkdir($uploadDir, 0755, true) && !is_dir($uploadDir)) {
            mnt_json_fail('Cartella allegati non scrivibile.');
        }

        $newSignature = uniqid('sig_', true) . '.png';
        $newSignature = preg_replace('/[^A-Za-z0-9._-]/', '_', $newSignature);

        if (file_put_contents($uploadDir . $newSignature, $binary) === false) {
            mnt_json_fail('Impossibile salvare la firma.');
        }

        if ($signaturePath) {
            mnt_delete_stored_file((string)$signaturePath);
        }

        $signaturePath = $newSignature;
    }

    $values = [
        'performed_at'         => $performedAt,
        'status'               => $status,
        'result'               => $result ?: null,
        'notes'                => $notes ?: null,
        'materials'            => $materials ?: null,
        'operator_employee_id' => $operatorId ?: null,
        'operator_name'        => $operatorName ?: null,
        'supplier_id'          => $supplierId ?: null,
        'signature_path'       => $signaturePath,
    ];

    if ($id > 0) {
        $assignments = [];
        foreach (array_keys($values) as $column) {
            $assignments[] = "$column = :$column";
        }

        $stmt = $pdo->prepare("UPDATE maint_interventions SET " . implode(', ', $assignments) . " WHERE id = :id");
        $stmt->execute($values + ['id' => $id]);

        $interventionId = $id;
        $action = 'intervention_updated';
    } else {
        $values['maintenance_id'] = $maintenanceId;
        $values['equipment_id'] = $equipmentId;
        $values['created_by'] = $currentUserId;

        $columns = array_keys($values);
        $placeholders = array_map(fn($column) => ':' . $column, $columns);

        $stmt = $pdo->prepare(
            "INSERT INTO maint_interventions (" . implode(', ', $columns) . ")
             VALUES (" . implode(', ', $placeholders) . ")"
        );
        $stmt->execute($values);

        $interventionId = (int)$pdo->lastInsertId();
        $action = 'intervention_created';
    }

    // Only completed interventions move the next due date; this call handles it
    mnt_recalc_maintenance($pdo, $maintenanceId);

    mnt_log($pdo, $action, $equipmentId, $maintenanceId, $interventionId, $currentUserId, $values);

    $stmt = $pdo->prepare("SELECT last_done_date, next_due_date FROM maint_maintenances WHERE id = ?");
    $stmt->execute([$maintenanceId]);
    $schedule = $stmt->fetch(PDO::FETCH_ASSOC) ?: [];

    mnt_json_ok(['id' => $interventionId, 'schedule' => $schedule]);
} catch (Throwable $e) {
    mnt_json_fail('Errore: ' . $e->getMessage());
}