// =====================================
// CONFIG
// =====================================
const WEBAPP_URL = "https://script.google.com/macros/s/AKfycbzdNCyVqmKBkRcCFWRNkqRxgo8afUoyRhQh3MQSFYWVPTM78UT8keOVNUF4X460cZdeVQ/exec";

// Max 5 images, 5MB each
const MAX_FILES = 5;
const MAX_FILE_SIZE_MB = 5;

// =====================================
// Convert file to Base64
// =====================================
function fileToBase64(file) {
  return new Promise((resolve, reject) => {
    const reader = new FileReader();
    reader.onload = () => {
      const base64 = reader.result.split(',')[1]; 
      resolve(base64);
    };
    reader.onerror = reject;
    reader.readAsDataURL(file);
  });
}

// =====================================
// Form Handler
// =====================================
document.addEventListener("DOMContentLoaded", function () {
  const form = document.getElementById("alnfArtistForm");
  if (!form) return;

  form.addEventListener("submit", async (e) => {
    e.preventDefault();

    const submitBtn = form.querySelector("button[type='submit']");
    submitBtn.disabled = true;
    submitBtn.textContent = "Submitting...";

    // Collect Fields
    const fields = {
      name: form.name.value.trim(),
      email: form.email.value.trim(),
      phone: form.phone.value.trim(),
      address: form.address.value.trim(),
      howLearned: form.howLearned.value,
      artDetails: form.artDetails.value.trim(),
      priceRange: form.priceRange.value.trim(),
      member: form.member.value,
      website: form.website.value.trim(),
      teach: form.teach.value,
      volunteer: form.volunteer.value,
      comments: form.comments.value.trim()
    };

    // Validate required fields
    for (const key in fields) {
      if (fields[key] === "" && form[key].hasAttribute("required")) {
        alert("Please complete all required fields.");
        submitBtn.disabled = false;
        submitBtn.textContent = "Submit Application";
        return;
      }
    }

    // Process Files
    const fileInput = document.getElementById("alnfImages");
    const files = fileInput.files;

    if (files.length === 0) {
      alert("Please attach at least one artwork image.");
      submitBtn.disabled = false;
      submitBtn.textContent = "Submit Application";
      return;
    }

    if (files.length > MAX_FILES) {
      alert("Please upload no more than 5 images.");
      submitBtn.disabled = false;
      submitBtn.textContent = "Submit Application";
      return;
    }

    const filePayload = [];

    for (let file of files) {
      if (file.size / 1024 / 1024 > MAX_FILE_SIZE_MB) {
        alert(`Each file must be under ${MAX_FILE_SIZE_MB}MB.`);
        submitBtn.disabled = false;
        submitBtn.textContent = "Submit Application";
        return;
      }
      const base64 = await fileToBase64(file);
      filePayload.push({
        filename: file.name,
        mimeType: file.type,
        content: base64
      });
    }

    // Build POST payload
    const payload = {
      fields: fields,
      files: filePayload
    };

    try {
      const response = await fetch(WEBAPP_URL, {
        method: "POST",
        mode: "cors",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify(payload)
      });

      const result = await response.json();

      if (result.success && result.redirect) {
        window.location.href = result.redirect;
        return;
      }

      alert("Error submitting form: " + (result.error || "Unknown error"));

    } catch (err) {
      console.error(err);
      alert("Network error. Please try again.");
    }

    submitBtn.disabled = false;
    submitBtn.textContent = "Submit Application";
  });
});