(() => {
  "use strict";

  const destination = "https://www.socialsleuth.xyz/face-search";
  const handoffEndpoint = "https://www.socialsleuth.xyz/api/face-search/handoff";
  const maxDimensionPx = 1600;
  const targetMaxBytes = 1.5 * 1024 * 1024;
  const backendMaxBytes = 2 * 1024 * 1024;
  const uploadHardLimitBytes = 50 * 1024 * 1024;
  const jpegQualitySteps = [0.82, 0.75, 0.68, 0.6, 0.5, 0.42];
  const uploadCard = document.getElementById("upload-card");
  const photoInput = document.getElementById("photo-input");
  const uploadEmpty = document.getElementById("upload-empty");
  const uploadPreview = document.getElementById("upload-preview");
  const previewImage = document.getElementById("preview-image");
  const fileName = document.getElementById("file-name");
  const changePhoto = document.getElementById("change-photo");
  const uploadError = document.getElementById("upload-error");
  const startSearch = document.getElementById("start-search");

  let previewUrl = "";
  let selectedFile = null;
  let isSubmitting = false;
  let finalHandoffUrl = "";

  const openTopLevelWindow = (url = "about:blank") => {
    return window.open(url, "_blank");
  };

  document
    .querySelectorAll(".how-it-works .section-button, .final-cta .primary-button")
    .forEach((link) => {
      link.addEventListener("click", (event) => {
        event.preventDefault();
        openTopLevelWindow(destination);
      });
    });

  const isSupportedImage = (file) => {
    if (!file) return false;
    const acceptedTypes = ["image/jpeg", "image/jpg", "image/png"];
    if (acceptedTypes.includes(file.type.toLowerCase())) return true;
    return /\.(jpe?g|png)$/i.test(file.name);
  };

  const openFilePicker = () => {
    if (isSubmitting) return;
    photoInput.click();
  };

  const showError = (message = "Please choose a JPG or PNG image.") => {
    uploadError.textContent = message;
    uploadError.hidden = false;
  };

  const clearError = () => {
    uploadError.hidden = true;
  };

  const displayFile = (file) => {
    if (!isSupportedImage(file)) {
      showError();
      return;
    }
    if (file.size > uploadHardLimitBytes) {
      showError("That photo is too large to process. Please choose another image.");
      return;
    }

    clearError();
    selectedFile = file;
    finalHandoffUrl = "";
    if (previewUrl) URL.revokeObjectURL(previewUrl);
    previewUrl = URL.createObjectURL(file);

    previewImage.src = previewUrl;
    previewImage.alt = `Preview of selected photo: ${file.name}`;
    fileName.textContent = file.name;
    uploadEmpty.hidden = true;
    uploadPreview.hidden = false;
    startSearch.disabled = false;
    startSearch.textContent = "START SEARCH";
  };

  photoInput.addEventListener("change", () => {
    displayFile(photoInput.files && photoInput.files[0]);
    photoInput.value = "";
  });

  uploadCard.addEventListener("click", openFilePicker);
  uploadCard.addEventListener("keydown", (event) => {
    if (event.key === "Enter" || event.key === " ") {
      event.preventDefault();
      openFilePicker();
    }
  });

  ["dragenter", "dragover"].forEach((eventName) => {
    uploadCard.addEventListener(eventName, (event) => {
      event.preventDefault();
      uploadCard.classList.add("is-dragging");
    });
  });

  ["dragleave", "drop"].forEach((eventName) => {
    uploadCard.addEventListener(eventName, (event) => {
      event.preventDefault();
      uploadCard.classList.remove("is-dragging");
    });
  });

  uploadCard.addEventListener("drop", (event) => {
    if (isSubmitting) return;
    displayFile(event.dataTransfer.files && event.dataTransfer.files[0]);
  });

  changePhoto.addEventListener("click", (event) => {
    event.stopPropagation();
    if (isSubmitting) return;
    openFilePicker();
  });

  const loadImage = (file) =>
    new Promise((resolve, reject) => {
      const url = URL.createObjectURL(file);
      const image = new Image();
      image.onload = () => resolve({ image, url });
      image.onerror = () => {
        URL.revokeObjectURL(url);
        reject(new Error("IMAGE_DECODE_FAILED"));
      };
      image.src = url;
    });

  const canvasToBlob = (canvas, quality) =>
    new Promise((resolve, reject) => {
      canvas.toBlob(
        (blob) => (blob ? resolve(blob) : reject(new Error("CANVAS_ENCODE_FAILED"))),
        "image/jpeg",
        quality
      );
    });

  // Converted from production's validated imageCompression.js settings so
  // common phone photos fit the existing 2MB temporary-session limit.
  const prepareImageForHandoff = async (file) => {
    if (file.size <= 1024 * 1024) return file;

    let sourceUrl = "";
    try {
      const loaded = await loadImage(file);
      const image = loaded.image;
      sourceUrl = loaded.url;
      const longEdge = Math.max(image.naturalWidth || 0, image.naturalHeight || 0);
      const scale = longEdge > maxDimensionPx ? maxDimensionPx / longEdge : 1;
      const width = Math.max(1, Math.round((image.naturalWidth || maxDimensionPx) * scale));
      const height = Math.max(1, Math.round((image.naturalHeight || maxDimensionPx) * scale));
      const canvas = document.createElement("canvas");
      canvas.width = width;
      canvas.height = height;
      const context = canvas.getContext("2d");
      if (!context) return file;
      context.imageSmoothingEnabled = true;
      context.imageSmoothingQuality = "high";
      context.drawImage(image, 0, 0, width, height);

      let blob = null;
      for (const quality of jpegQualitySteps) {
        blob = await canvasToBlob(canvas, quality);
        if (blob.size <= targetMaxBytes) break;
      }
      if (!blob || blob.size >= file.size) return file;

      const baseName = String(file.name || "photo").replace(/\.[^./]+$/, "") || "photo";
      return new File([blob], `${baseName}.jpg`, {
        type: "image/jpeg",
        lastModified: Date.now(),
      });
    } finally {
      if (sourceUrl) URL.revokeObjectURL(sourceUrl);
    }
  };

  startSearch.addEventListener("click", async () => {
    if (startSearch.disabled || isSubmitting) return;
    if (finalHandoffUrl) {
      window.open(finalHandoffUrl, "_blank");
      return;
    }
    if (!selectedFile) return;

    isSubmitting = true;
    startSearch.disabled = true;
    startSearch.textContent = "PREPARING SEARCH…";
    clearError();

    try {
      const preparedFile = await prepareImageForHandoff(selectedFile);
      if (!isSupportedImage(preparedFile) || preparedFile.size > backendMaxBytes) {
        throw new Error("IMAGE_TOO_LARGE");
      }

      startSearch.textContent = "TRANSFERRING PHOTO…";
      const form = new FormData();
      form.append("image", preparedFile, preparedFile.name || "photo.jpg");
      const response = await fetch(handoffEndpoint, {
        method: "POST",
        body: form,
        credentials: "omit",
      });
      const data = await response.json().catch(() => null);
      if (!response.ok || !data?.ok || typeof data.handoffToken !== "string") {
        throw new Error(data?.error || "HANDOFF_FAILED");
      }

      finalHandoffUrl = `${destination}?handoff=${encodeURIComponent(data.handoffToken)}`;
      isSubmitting = false;
      startSearch.disabled = false;
      startSearch.textContent = "CONTINUE TO SEARCH";
    } catch (_) {
      finalHandoffUrl = "";
      isSubmitting = false;
      startSearch.disabled = false;
      startSearch.textContent = "START SEARCH";
      showError("We couldn't transfer that photo. Please try again.");
    }
  });

  document.querySelectorAll(".faq-question").forEach((button) => {
    const answer = document.getElementById(button.getAttribute("aria-controls"));
    const item = button.closest(".faq-item");

    button.addEventListener("click", () => {
      const willOpen = button.getAttribute("aria-expanded") !== "true";
      button.setAttribute("aria-expanded", String(willOpen));
      item.classList.toggle("is-open", willOpen);

      if (willOpen) {
        answer.hidden = false;
        requestAnimationFrame(() => answer.classList.add("is-open"));
      } else {
        answer.classList.remove("is-open");
        window.setTimeout(() => {
          if (button.getAttribute("aria-expanded") === "false") answer.hidden = true;
        }, 230);
      }
    });
  });

  window.addEventListener("beforeunload", () => {
    if (previewUrl) URL.revokeObjectURL(previewUrl);
  });
})();