paad/export/faltas_excel.php

<?php

$fecha = date('d_m_Y');
header("Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
header("Content-Disposition: attachment;filename=horario_$fecha.xlsx");
header("Cache-Control: max-age=0");

require_once "../vendor/autoload.php";

use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\Style\Border;
use PhpOffice\PhpSpreadsheet\Style\Color;
use PhpOffice\PhpSpreadsheet\Style\Fill;
use PhpOffice\PhpSpreadsheet\Style\Alignment;
use PhpOffice\PhpSpreadsheet\IOFactory;

$spreadsheet = new Spreadsheet();
$sheet = $spreadsheet->getActiveSheet();

// Image settings
$drawing = new \PhpOffice\PhpSpreadsheet\Worksheet\Drawing();
$drawing->setName('La Salle')
    ->setDescription('La Salle')
    ->setPath('../imagenes/logo.png')
    ->setCoordinates('B1')
    ->setHeight(100)
    ->setOffsetX(10)
    ->setWorksheet($spreadsheet->getActiveSheet());

$json = file_get_contents('php://input');
$data = json_decode($json, true);

empty($data) and die(json_encode(['error' => 'No se recibieron datos', 'data' => $data]));

$data_excel = array(
    "CLAVE" => 'profesor_clave',
    "PROFESOR" => 'profesor_nombre',
    "CORREO" => 'profesor_correo',
    "FALTAS" => 'faltas',
    "TOTAL" => 'total',
    "PORCENTAJE" => 'porcentaje',
); // Same as before



const ROW = 6;
// Merge cells from A1 to C+ ROW
$sheet->mergeCells('A1:B' . (ROW - 1));
// Merge cells from D1 to size of $data_excel + 1
$sheet->mergeCells('C1:' . chr(65 + count($data_excel) - 1) . (ROW - 1));

// Set the title in D1 Sistema de Auditoría de Asistencia
$sheet->setCellValue('C1', 'Sistema de Auditoría de Asistencia');
$sheet->getStyle('C1')->applyFromArray([
    'font' => [
        'bold' => true,
        'size' => 30,
        'name' => 'Indivisa Text Sans',
        'color' => ['argb' => '001d68'],
    ],
    'alignment' => [
        'vertical' => Alignment::VERTICAL_CENTER,
    ],
]);


$lastColumnLetter = chr(65 + count($data_excel) - 1);
$headers_range = 'A' . ROW . ':' . $lastColumnLetter . ROW;

$keys = array_keys($data_excel);
array_walk($keys, function ($key, $index) use ($sheet) {
    $sheet->setCellValue(chr(65 + $index) . ROW, $key);
});
// Apply the header styles
$sheet->getStyle($headers_range)->applyFromArray([
    'font' => [
        'bold' => true,
        'size' => 15,
        'name' => 'Indivisa Text Sans',
        'color' => ['argb' => Color::COLOR_WHITE],
    ],
    'alignment' => [
        'horizontal' => Alignment::HORIZONTAL_CENTER,
        'vertical' => Alignment::VERTICAL_CENTER,
    ],
    'fill' => [
        'fillType' => Fill::FILL_SOLID,
        'startColor' => ['argb' => '001d68'],
    ]
]);

// set filters
$sheet->setAutoFilter($headers_range);



// Styles that are common for all rows can be set outside the loop

const DEFAULT_FONT = [
    'size' => 12,
    'name' => 'Indivisa Text Sans',
    'color' => ['argb' => '001d68']
];

const DEFAULT_STYLE = [
    'alignment' => [
        'vertical' => Alignment::VERTICAL_CENTER,
        'wrapText' => true,
    ],
    'font' => DEFAULT_FONT,
    'borders' => [
        'outline' => [
            'borderStyle' => Border::BORDER_THIN,
            'color' => ['argb' => Color::COLOR_WHITE],
        ]
    ]
];

foreach ($data as $index => $registro) {
    $pair = $index % 2 == 0;
    $cellRange = 'A' . (ROW + $index + 1) . ':' . $lastColumnLetter . (ROW + $index + 1);
    $styleArray = DEFAULT_STYLE;
    $styleArray['fill'] = [
        'fillType' => Fill::FILL_SOLID,
        'startColor' => ['argb' => $pair ? 'd4d9dd' : 'f6f7f8'],
    ];

    $sheet->getStyle($cellRange)->applyFromArray($styleArray);
    $values = array_values($data_excel);
    array_walk($values, function ($row, $column_index) use ($sheet, $index, $registro) {
        $cellLocation = chr(65 + $column_index) . (ROW + $index + 1);
        $sheet->setCellValue($cellLocation, $registro[$row]);
    });
}


foreach ($sheet->getColumnIterator() as $column) {
    $sheet->getColumnDimension($column->getColumnIndex())->setAutoSize(true);
}

$writer = IOFactory::createWriter($spreadsheet, 'Xlsx');
$writer->save('php://output');