<!DOCTYPE html>
<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
  <head>
  <th:block th:insert="~{fragments/common :: head(title=#{sign.title}, header=#{sign.header})}"></th:block>
    <link rel="stylesheet" href="css/sign.css">
  <th:block th:each="font : ${fonts}">
    <style th:inline="text">
      @font-face {
        font-family: "[[${font.name}]]";
        src: url('fonts/[[${font.name}]].[[${font.extension}]]') format('[[${font.type}]]');
      }

      #font-select option[value="[[${font.name}]]"] {
        font-family: "[[${font.name}]]", cursive;
      }
      #font-select option[value='/*[[${font.name}]]*/'] {
        font-family: '/*[[${font.name}]]*/', cursive;
      }
    </style>
  </th:block>
    <script src="js/thirdParty/signature_pad.umd.min.js"></script>
    <script src="js/thirdParty/interact.min.js"></script>
  </head>

  <body>
    <div id="page-container">
      <div id="content-wrap">
        <th:block th:insert="~{fragments/navbar.html :: navbar}"></th:block>
        <br><br>
        <div class="container">
          <div class="row justify-content-center">
            <div class="col-md-6">
              <h2 th:text="#{sign.header}"></h2>

              <!-- pdf selector -->
              <div th:replace="~{fragments/common :: fileSelector(name='pdf-upload', multiple=false, accept='application/pdf')}"></div>
              <script>
                let originalFileName = '';
                document.querySelector('input[name=pdf-upload]').addEventListener('change', async (event) => {
                  const file = event.target.files[0];
                  if (file) {
                    originalFileName = file.name.replace(/\.[^/.]+$/, "");
                    const pdfData = await file.arrayBuffer();
                    pdfjsLib.GlobalWorkerOptions.workerSrc = 'pdfjs/pdf.worker.js'
                    const pdfDoc = await pdfjsLib.getDocument({ data: pdfData }).promise;
                    await DraggableUtils.renderPage(pdfDoc, 0);

                    document.querySelectorAll(".show-on-file-selected").forEach(el => {
                      el.style.cssText = '';
                    })
                  }
                });
                document.addEventListener("DOMContentLoaded", () => {
                  document.querySelectorAll(".show-on-file-selected").forEach(el => {
                    el.style.cssText = "display:none !important";
                  })
                });
              </script>
              <div class="tab-group show-on-file-selected">
                <div class="tab-container" th:title="#{sign.upload}">
                  <div th:replace="~{fragments/common :: fileSelector(name='image-upload', multiple=true, accept='image/*', inputText=#{imgPrompt})}"></div>
                    <script>
                      const imageUpload = document.querySelector('input[name=image-upload]');
                      imageUpload.addEventListener('change', e => {
                        if(!e.target.files) {
                          return;
                        }
                        for (const imageFile of e.target.files) {
                          var reader = new FileReader();
                          reader.readAsDataURL(imageFile);
                          reader.onloadend = function (e) {
                            DraggableUtils.createDraggableCanvasFromUrl(e.target.result);
                          };
                        }
                      });
                    </script>
                  </div>
                  <div class="tab-container drawing-pad-container" th:title="#{sign.draw}">
                    <canvas id="drawing-pad-canvas"></canvas>
                    <br>
                    <button id="clear-signature" class="btn btn-outline-danger mt-2" onclick="signaturePad.clear()" th:text="#{sign.clear}"></button>
                    <button id="save-signature" class="btn btn-outline-success mt-2" onclick="addDraggableFromPad()" th:text="#{sign.add}"></button>
                    <script>
                      const signaturePadCanvas = document.getElementById('drawing-pad-canvas');
                      const signaturePad = new SignaturePad(signaturePadCanvas, {
                        minWidth: 1,
                        maxWidth: 2,
                        penColor: 'black',
                      });
                      function addDraggableFromPad() {
                        if (signaturePad.isEmpty()) return;
                        const startTime = Date.now();
                        const croppedDataUrl = getCroppedCanvasDataUrl(signaturePadCanvas)
                        console.log(Date.now() - startTime);
                        DraggableUtils.createDraggableCanvasFromUrl(croppedDataUrl);
                      }
                      function getCroppedCanvasDataUrl(canvas) {
                        // code is from: https://github.com/szimek/signature_pad/issues/49#issuecomment-1104035775
                        let originalCtx = canvas.getContext('2d');

                        let originalWidth = canvas.width;
                        let originalHeight = canvas.height;
                        let imageData = originalCtx.getImageData(0,0, originalWidth, originalHeight);

                        let minX = originalWidth + 1, maxX = -1, minY = originalHeight + 1, maxY = -1, x = 0, y = 0, currentPixelColorValueIndex;

                        for (y = 0; y < originalHeight; y++) {
                          for (x = 0; x < originalWidth; x++) {
                            currentPixelColorValueIndex = (y * originalWidth + x) * 4;
                            let currentPixelAlphaValue = imageData.data[currentPixelColorValueIndex + 3];
                            if (currentPixelAlphaValue > 0) {
                              if (minX > x) minX = x;
                              if (maxX < x) maxX = x;
                              if (minY > y) minY = y;
                              if (maxY < y) maxY = y;
                            }
                          }
                        }

                        let croppedWidth = maxX - minX;
                        let croppedHeight = maxY - minY;
                        if (croppedWidth < 0 || croppedHeight < 0) return null;
                        let cuttedImageData = originalCtx.getImageData(minX, minY, croppedWidth, croppedHeight);

                        let croppedCanvas = document.createElement('canvas'),
                            croppedCtx    = croppedCanvas.getContext('2d');

                        croppedCanvas.width = croppedWidth;
                        croppedCanvas.height = croppedHeight;
                        croppedCtx.putImageData(cuttedImageData, 0, 0);

                        return croppedCanvas.toDataURL();
                      }
                      function resizeCanvas() {
                        // When zoomed out to less than 100%, for some very strange reason,
                        // some browsers report devicePixelRatio as less than 1
                        // and only part of the canvas is cleared then.
                        var ratio = Math.max(window.devicePixelRatio || 1, 1);
                        var additionalFactor = 10;

                        signaturePadCanvas.width = signaturePadCanvas.offsetWidth * ratio * additionalFactor;
                        signaturePadCanvas.height = signaturePadCanvas.offsetHeight * ratio * additionalFactor;
                        signaturePadCanvas.getContext("2d").scale(ratio * additionalFactor, ratio * additionalFactor);

                        // This library does not listen for canvas changes, so after the canvas is automatically
                        // cleared by the browser, SignaturePad#isEmpty might still return false, even though the
                        // canvas looks empty, because the internal data of this library wasn't cleared. To make sure
                        // that the state of this library is consistent with visual state of the canvas, you
                        // have to clear it manually.
                        signaturePad.clear();
                      }
                      new IntersectionObserver((entries, observer) => {
                        if (entries.some(entry => entry.intersectionRatio > 0)) {
                          resizeCanvas();
                        }
                      }).observe(signaturePadCanvas);
                      new ResizeObserver(resizeCanvas).observe(signaturePadCanvas);
                    </script>
                  </div>
                  <div class="tab-container" th:title="#{sign.text}">
                    <label class="form-check-label" for="sigText" th:text="#{text}"></label>
                    <textarea class="form-control" id="sigText" name="sigText" rows="3"></textarea>
                    <label th:text="#{font}"></label>
                    <select class="form-control" name="font" id="font-select">
                      <option th:each="font : ${fonts}" th:value="${font.name}" th:text="${font.name}" th:class="${font.name.toLowerCase()+'-font'}">
                      </option>
                    </select>
                    <div class="margin-auto-parent">
                      <button id="save-text-signature" class="btn btn-outline-success mt-2 margin-center" onclick="addDraggableFromText()" th:text="#{sign.add}"></button>
                    </div>
                    <script>
                      function addDraggableFromText() {
                        const sigText = document.getElementById('sigText').value;
                        const font = document.querySelector('select[name=font]').value;
                        const fontSize = 100;

                        const canvas = document.createElement('canvas');
                        const ctx = canvas.getContext('2d');
                        ctx.font = `${fontSize}px ${font}`;
                        const textWidth = ctx.measureText(sigText).width;
                        const textHeight = fontSize;

                        let paragraphs = sigText.split(/\r?\n/);

                        canvas.width = textWidth;
                        canvas.height = paragraphs.length * textHeight*1.35; //for tails
                        ctx.font = `${fontSize}px ${font}`;

                        ctx.textBaseline = 'top';

                        let y = 0;

                        paragraphs.forEach(paragraph => {
                          ctx.fillText(paragraph, 0, y);
                          y += fontSize;
                        });

                        const dataURL = canvas.toDataURL();
                        DraggableUtils.createDraggableCanvasFromUrl(dataURL);
                      }
                    </script>
                    <script>
                      const sigTextInput = document.getElementById('sigText');
                      const fontSelect = document.getElementById('font-select');

                      const updateOptionTexts = () => {
                        Array.from(fontSelect.options).forEach(option => {
                          const fontName = option.value.replace(/-regular$/i, '');
                          option.text = sigTextInput.value || fontName;
                        });
                      }

                      sigTextInput.addEventListener('input', updateOptionTexts);

                      fontSelect.addEventListener('change', (e) => {
                        e.target.style.fontFamily = e.target.value;
                        updateOptionTexts();
                      });

                      // Manually trigger the change event
                      fontSelect.dispatchEvent(new Event('change'));
                  </script>
                </div>
              </div>

              <!-- draggables box -->
              <div id="box-drag-container" class="show-on-file-selected">
                <canvas id="pdf-canvas"></canvas>
                <script src="js/draggable-utils.js"></script>
                <div class="draggable-buttons-box ignore-rtl">
                  <button class="btn btn-outline-secondary" onclick="DraggableUtils.deleteDraggableCanvas(DraggableUtils.getLastInteracted())">
                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-trash" viewBox="0 0 16 16">
                      <path d="M5.5 5.5A.5.5 0 0 1 6 6v6a.5.5 0 0 1-1 0V6a.5.5 0 0 1 .5-.5Zm2.5 0a.5.5 0 0 1 .5.5v6a.5.5 0 0 1-1 0V6a.5.5 0 0 1 .5-.5Zm3 .5a.5.5 0 0 0-1 0v6a.5.5 0 0 0 1 0V6Z"/>
                      <path d="M14.5 3a1 1 0 0 1-1 1H13v9a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V4h-.5a1 1 0 0 1-1-1V2a1 1 0 0 1 1-1H6a1 1 0 0 1 1-1h2a1 1 0 0 1 1 1h3.5a1 1 0 0 1 1 1v1ZM4.118 4 4 4.059V13a1 1 0 0 0 1 1h6a1 1 0 0 0 1-1V4.059L11.882 4H4.118ZM2.5 3h11V2h-11v1Z"/>
                    </svg>
                  </button>
                  <button class="btn btn-outline-secondary" onclick="document.documentElement.getAttribute('dir')==='rtl' ? DraggableUtils.incrementPage() : DraggableUtils.decrementPage()" style="margin-left:auto">
                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-chevron-left" viewBox="0 0 16 16">
                      <path fill-rule="evenodd" d="M11.354 1.646a.5.5 0 0 1 0 .708L5.707 8l5.647 5.646a.5.5 0 0 1-.708.708l-6-6a.5.5 0 0 1 0-.708l6-6a.5.5 0 0 1 .708 0z"/>
                    </svg>
                  </button>
                  <button class="btn btn-outline-secondary" onclick="document.documentElement.getAttribute('dir')==='rtl' ? DraggableUtils.decrementPage() : DraggableUtils.incrementPage()">
                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-chevron-right" viewBox="0 0 16 16">
                      <path fill-rule="evenodd" d="M4.646 1.646a.5.5 0 0 1 .708 0l6 6a.5.5 0 0 1 0 .708l-6 6a.5.5 0 0 1-.708-.708L10.293 8 4.646 2.354a.5.5 0 0 1 0-.708z"/>
                    </svg>
                  </button>
                </div>
              </div>

              <!-- download button -->
              <div class="margin-auto-parent">
                <button id="download-pdf" class="btn btn-primary mb-2 show-on-file-selected margin-center" th:text="#{downloadPdf}"></button>
              </div>

              <script>
                document.getElementById("download-pdf").addEventListener('click', async() => {
                  const modifiedPdf = await DraggableUtils.getOverlayedPdfDocument();
                  const modifiedPdfBytes = await modifiedPdf.save();
                  const blob = new Blob([modifiedPdfBytes], { type: 'application/pdf' });
                  const link = document.createElement('a');
                  link.href = URL.createObjectURL(blob);
                  link.download = originalFileName + '_signed.pdf';
                  link.click();
                });
              </script>
            </div>
          </div>
        </div>
      </div>
      <th:block th:insert="~{fragments/footer.html :: footer}"></th:block>
    </div>
  </body>
</html>