// pantry-vision frontend logic (docs/project-plan.md Phase 17). Vanilla JS, no
// framework, no build step — same "vendored, dependency-free" choice as the digest/
// admin canvas SDKs' render.js.
//
// Config comes from URL query params (?api=...&token=...), set by the
// kitchen-display kiosk's own launch command, NOT hardcoded here — this file is a
// generic static asset with no secret in it, served read-only by pantry-web to
// whatever device points a browser at it.
"use strict";

const params = new URLSearchParams(location.search);
const API = (params.get("api") || "").replace(/\/$/, "");
const TOKEN = params.get("token") || "";

if (!API || !TOKEN) {
  document.body.innerHTML =
    '<p class="error" style="padding:24px">pantry-vision not configured — missing ' +
    "?api=&token= in the URL. See hosts/kitchen-display/configs/sway/pantry-kiosk.</p>";
  throw new Error("pantry-vision: missing ?api=/&token= query params");
}

function api(path, options) {
  options = options || {};
  options.headers = Object.assign({ Authorization: `Bearer ${TOKEN}` }, options.headers || {});
  return fetch(`${API}${path}`, options).then((res) => {
    if (!res.ok) {
      return res.json().catch(() => ({})).then((body) => {
        throw new Error(body.error || `${res.status} ${res.statusText}`);
      });
    }
    return res.json();
  });
}

// --- Tabs --------------------------------------------------------------------
const tabs = document.querySelectorAll(".tab");
const panels = document.querySelectorAll(".panel");

function activateTab(name) {
  tabs.forEach((t) => t.classList.toggle("active", t.dataset.tab === name));
  panels.forEach((p) => p.classList.toggle("active", p.id === name));
  if (name === "inventory") loadInventory();
  if (name === "recipes") loadRecipes();
  if (name === "scan") resetScan();
}

tabs.forEach((t) => t.addEventListener("click", () => activateTab(t.dataset.tab)));

// A "Show <tab>" MQTT command from touchpanel-style HA control arrives as a URL
// fragment reload (hosts/kitchen-display/agent kills and relaunches Chromium at
// index.html#recipes, same pattern as the thin client's digest-browser) — honour it
// on load, same as any manual tap.
if (location.hash) {
  const initial = location.hash.slice(1);
  if (["scan", "inventory", "recipes"].includes(initial)) activateTab(initial);
}

// --- Scan ----------------------------------------------------------------------
const video = document.getElementById("camera-preview");
const captureBtn = document.getElementById("capture-btn");
const cameraError = document.getElementById("camera-error");
const scanCamera = document.getElementById("scan-camera");
const scanResult = document.getElementById("scan-result");
const capturedFrame = document.getElementById("captured-frame");
const confirmForm = document.getElementById("confirm-form");
const confirmStatus = document.getElementById("confirm-status");
const retakeBtn = document.getElementById("retake-btn");

let stream = null;

function startCamera() {
  if (stream) return;
  navigator.mediaDevices
    .getUserMedia({ video: { facingMode: "environment" }, audio: false })
    .then((s) => {
      stream = s;
      video.srcObject = s;
      cameraError.hidden = true;
    })
    .catch((err) => {
      cameraError.textContent = `Camera unavailable: ${err.message}. See hosts/kitchen-display/README.md.`;
      cameraError.hidden = false;
    });
}

function resetScan() {
  scanResult.hidden = true;
  scanCamera.hidden = false;
  confirmStatus.textContent = "";
  startCamera();
}

captureBtn.addEventListener("click", () => {
  if (!stream) return;
  capturedFrame.width = video.videoWidth;
  capturedFrame.height = video.videoHeight;
  capturedFrame.getContext("2d").drawImage(video, 0, 0);

  scanCamera.hidden = true;
  scanResult.hidden = false;
  confirmStatus.textContent = "Identifying…";
  document.getElementById("f-confidence").textContent = "";

  capturedFrame.toBlob(
    (blob) => {
      api("/identify", { method: "POST", body: blob, headers: { "Content-Type": "image/jpeg" } })
        .then((proposal) => {
          document.getElementById("f-name").value = proposal.name || "";
          document.getElementById("f-category").value = proposal.category || "other";
          const days = Number.isFinite(proposal.estimated_shelf_life_days)
            ? proposal.estimated_shelf_life_days
            : 7;
          const due = new Date();
          due.setDate(due.getDate() + days);
          document.getElementById("f-date").value = due.toISOString().slice(0, 10);
          document.getElementById("f-confidence").textContent =
            `Model confidence: ${proposal.confidence || "unknown"}` +
            (proposal.note ? ` — ${proposal.note}` : "") +
            ". Review before confirming.";
          confirmStatus.textContent = "";
        })
        .catch((err) => {
          confirmStatus.textContent = `Could not identify: ${err.message}. Fill in manually.`;
        });
    },
    "image/jpeg",
    0.85
  );
});

retakeBtn.addEventListener("click", resetScan);

confirmForm.addEventListener("submit", (event) => {
  event.preventDefault();
  confirmStatus.textContent = "Adding…";
  api("/confirm", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({
      name: document.getElementById("f-name").value.trim(),
      category: document.getElementById("f-category").value,
      best_before_date: document.getElementById("f-date").value,
      quantity: Number(document.getElementById("f-quantity").value) || 1,
    }),
  })
    .then(() => {
      confirmStatus.textContent = "Added. Put it away!";
      setTimeout(resetScan, 1500);
    })
    .catch((err) => {
      confirmStatus.textContent = `Could not add: ${err.message}`;
    });
});

// --- Inventory -------------------------------------------------------------------
function urgencyClass(daysLeft) {
  if (daysLeft === null || daysLeft === undefined) return "";
  if (daysLeft < 0) return "urgent-expired";
  if (daysLeft <= 2) return "urgent-soon";
  if (daysLeft <= 7) return "urgent-week";
  return "";
}

function loadInventory() {
  const el = document.getElementById("inventory-list");
  api("/inventory")
    .then((data) => {
      const items = data.items || [];
      if (!items.length) {
        el.innerHTML = '<p class="hint">Nothing in stock yet — scan something!</p>';
        return;
      }
      el.innerHTML = items
        .map((item) => {
          const days = item.days_left;
          const label =
            days === null || days === undefined
              ? "no date"
              : days < 0
              ? `expired ${-days}d ago`
              : days === 0
              ? "expires today"
              : `${days}d left`;
          return `<div class="card ${urgencyClass(days)}">
            <span class="card-name">${escapeHtml(item.name)}</span>
            <span class="card-amount">×${escapeHtml(String(item.amount ?? ""))}</span>
            <span class="card-due">${escapeHtml(label)}</span>
          </div>`;
        })
        .join("");
    })
    .catch((err) => {
      el.innerHTML = `<p class="error">Could not load inventory: ${escapeHtml(err.message)}</p>`;
    });
}

// --- Recipes -----------------------------------------------------------------
function loadRecipes() {
  const el = document.getElementById("recipes-list");
  api("/recipes")
    .then((data) => {
      const recipes = data.recipes || [];
      if (!recipes.length) {
        el.innerHTML = '<p class="hint">No recipes in Grocy yet.</p>';
        return;
      }
      el.innerHTML = recipes
        .map((r) => {
          const badge = r.fulfilled === true ? "✓ can make now" : r.fulfilled === false ? "missing items" : "";
          return `<div class="card">
            <span class="card-name">${escapeHtml(r.name || "")}</span>
            <span class="card-due">${escapeHtml(badge)}</span>
          </div>`;
        })
        .join("");
    })
    .catch((err) => {
      el.innerHTML = `<p class="error">Could not load recipes: ${escapeHtml(err.message)}</p>`;
    });
}

function escapeHtml(s) {
  return String(s).replace(/[&<>"']/g, (c) => ({ "&": "&amp;", "<": "&lt;", ">": "&gt;", '"': "&quot;", "'": "&#39;" }[c]));
}

// Start on whatever tab is active (default: scan).
resetScan();