"use strict";

const $ = id => document.getElementById(id);
const input = $("image-file"), original = $("original"), cornersCanvas = $("corners");
const processed = $("processed"), evidenceCanvas = $("evidence");
const run = $("run"), status = $("status"), rotation = $("rotation"), finePrint = $("fine-print");
const initialCorners = () => [[0, 0], [1, 0], [1, 1], [0, 1]];
let corners = initialCorners(), edited = false, busy = false, ready = false;
let objectUrl = null, drag = null, result = null, selectedEvidence = null;
const manual = {classic: new Map(), vision: new Map()};
const suppressed = {classic: new Set(), vision: new Set()};
const priorityCodes = ["C.1.1", "C.1.2", "C.1.3", "B", "2.1", "2.2"];
const reviewMethods = new Set(["merged_code", "vl_table_context_code", "caption_region_next_line", "surname_above_forename"]);
const fieldNames = {"A":"Kennzeichen","C.1.1":"Name / Firmenname","C.1.2":"Vorname",
  "C.1.3":"Anschrift","B":"Erstzulassung","2.1":"Herstellerschlüssel (HSN)",
  "2.2":"Typschlüssel (TSN)","2":"Hersteller","D.1":"Marke","D.2":"Typ / Variante",
  "D.3":"Handelsbezeichnung","E":"Fahrzeug-Identifizierungsnummer","P.3":"Kraftstoffart",
  "R":"Farbe","17":"Merkmal zur Betriebserlaubnis"};

function setStatus(message, kind = "") {
  status.textContent = message;
  status.className = `status ${kind}`;
}
function validCorners() {
  if (!ready) return false;
  if (!edited) return true;
  const w = original.naturalWidth, h = original.naturalHeight;
  const points = corners.map(([x, y]) => [x * w, y * h]);
  const edges = points.map((p, i) => [points[(i + 1) % 4][0] - p[0], points[(i + 1) % 4][1] - p[1]]);
  const crosses = edges.map((a, i) => a[0] * edges[(i + 1) % 4][1] - a[1] * edges[(i + 1) % 4][0]);
  const area = Math.abs(points.reduce((sum, p, i) => sum + p[0] * points[(i + 1) % 4][1] - p[1] * points[(i + 1) % 4][0], 0)) / 2;
  return crosses.every(value => value > 0) && area > .02 * w * h &&
    edges.every(([x, y]) => Math.hypot(x, y) >= 30);
}
function updateControls() {
  input.disabled = busy;
  $("reset-corners").disabled = !ready || busy;
  rotation.disabled = busy;
  finePrint.disabled = busy;
  run.disabled = busy || !validCorners();
}
function drawCorners() {
  const w = original.naturalWidth, h = original.naturalHeight;
  if (!w || !h) return;
  cornersCanvas.width = w;
  cornersCanvas.height = h;
  const ctx = cornersCanvas.getContext("2d");
  const pts = corners.map(([x, y]) => [x * (w - 1), y * (h - 1)]);
  ctx.strokeStyle = "#1459dd";
  ctx.lineWidth = Math.max(5, w / 550);
  ctx.beginPath();
  pts.forEach(([x, y], i) => i ? ctx.lineTo(x, y) : ctx.moveTo(x, y));
  ctx.closePath();ctx.stroke();
  const radius = Math.max(25, w / 110);
  pts.forEach(([x, y], i) => {
    ctx.beginPath();ctx.arc(x, y, radius, 0, 2 * Math.PI);
    ctx.fillStyle = "#fff";ctx.fill();ctx.stroke();
    ctx.fillStyle = "#1547a5";ctx.font = `bold ${Math.max(22, w / 125)}px system-ui`;
    ctx.fillText(String(i + 1), Math.min(w - radius, x + radius * .9), Math.max(radius, y - radius * .65));
  });
}
function pointInCanvas(event) {
  const b = cornersCanvas.getBoundingClientRect();
  return [(event.clientX - b.left) / b.width, (event.clientY - b.top) / b.height];
}
cornersCanvas.addEventListener("pointerdown", event => {
  if (!ready || busy) return;
  const b = cornersCanvas.getBoundingClientRect();
  const [x, y] = pointInCanvas(event);
  const distances = corners.map(([cx, cy]) => Math.hypot((cx - x) * b.width, (cy - y) * b.height));
  const index = distances.indexOf(Math.min(...distances));
  if (distances[index] > 32) return;
  drag = index;
  cornersCanvas.setPointerCapture(event.pointerId);
  event.preventDefault();
});
cornersCanvas.addEventListener("pointermove", event => {
  if (drag === null || busy) return;
  const [x, y] = pointInCanvas(event);
  corners[drag] = [Math.max(0, Math.min(1, x)), Math.max(0, Math.min(1, y))];
  edited = true; result = null; $("comparison").hidden = true;
  drawCorners();updateControls();
  setStatus(validCorners() ? "Ecken geändert. Bitte beide Verfahren neu starten." :
    "Ecken müssen ein nicht gekreuztes Viereck um das Dokument bilden.", validCorners() ? "" : "error");
});
function finishDrag() {drag = null;}
cornersCanvas.addEventListener("pointerup", finishDrag);
cornersCanvas.addEventListener("pointercancel", finishDrag);
$("reset-corners").addEventListener("click", () => {
  corners = initialCorners(); edited = false; result = null;
  $("comparison").hidden = true;drawCorners();updateControls();setStatus("Ganzes Bild ausgewählt.");
});
rotation.addEventListener("change", () => {
  result = null;$("comparison").hidden = true;setStatus("Leserichtung geändert. Bitte erneut vergleichen.");
});
finePrint.addEventListener("change", () => {
  result = null;$("comparison").hidden = true;
  setStatus("OCR-Detailgrad geändert. Bitte erneut vergleichen.");
});
input.addEventListener("change", () => {
  if (objectUrl) URL.revokeObjectURL(objectUrl);
  objectUrl = null; ready = false; edited = false; corners = initialCorners();
  drag = null; result = null; selectedEvidence = null;
  manual.classic.clear();manual.vision.clear();
  suppressed.classic.clear();suppressed.vision.clear();
  $("comparison").hidden = true;rotation.value = "0";
  const file = input.files?.[0];
  $("original-wrap").hidden = !file;
  $("file-name").textContent = file ? `${file.name} · ${(file.size / 1048576).toFixed(2)} MiB` : "JPEG oder PNG, maximal 16 MiB.";
  if (file) {objectUrl = URL.createObjectURL(file);original.src = objectUrl;}
  else original.removeAttribute("src");
  setStatus("");updateControls();
});
original.addEventListener("load", () => {
  ready = true;drawCorners();updateControls();
  $("file-name").textContent += ` · ${original.naturalWidth} × ${original.naturalHeight} Pixel`;
});
original.addEventListener("error", () => {
  ready = false;updateControls();setStatus("Das Bild kann nicht geöffnet werden. Bitte JPEG oder PNG verwenden.", "error");
});
window.addEventListener("pagehide", () => {if (objectUrl) URL.revokeObjectURL(objectUrl);});

const errorText = {
  busy: "Ein Vergleich läuft bereits.", unsupported_media_type: "Nur JPEG und PNG sind erlaubt.",
  upload_too_large: "Das Bild ist größer als 16 MiB.", upload_timeout: "Der Upload hat zu lange gedauert.",
  invalid_image: "Die Bilddatei lässt sich nicht vollständig lesen.",
  unsupported_encoding: "Der Bildinhalt ist kein unterstütztes JPEG oder PNG.",
  image_too_large: "Die Auflösung überschreitet 24 Megapixel oder 10.000 Pixel pro Seite.",
  invalid_corners: "Die vier Ecken bilden kein gültiges Dokumentviereck.",
  invalid_rotation: "Die gewählte Drehung ist ungültig.",
  invalid_detail: "Der OCR-Detailgrad ist ungültig.",
  classic_timeout: "Die klassische OCR hat das Zeitlimit überschritten.",
  classic_models_missing: "Die lokalen OCR-Modelle fehlen. Zuerst die Modell-Einrichtung aus der README ausführen.",
  classic_failed: "Die klassische OCR ist lokal fehlgeschlagen.",
  classic_invalid: "Die klassische OCR hat ein ungültiges Ergebnis geliefert.",
  vision_timeout: "PaddleOCR-VL hat das Zeitlimit überschritten.",
  vision_failed: "PaddleOCR-VL konnte auf der konfigurierten eigenen Hardware nicht ausgeführt werden.",
  vision_disabled: "Vision ist in dieser Installation deaktiviert.",
  vision_config_error: "Die Vision-Konfiguration ist unvollständig oder ungültig.",
  vision_models_missing: "Die lokalen Vision-Modelle fehlen. Zuerst die Modell-Einrichtung aus der README ausführen.",
  vision_invalid: "PaddleOCR-VL hat ein ungültiges Ergebnis geliefert.",
};

function element(tag, value, className = "") {
  const node = document.createElement(tag);
  node.textContent = value;
  if (className) node.className = className;
  return node;
}
function drawEvidence() {
  if (!result || !processed.naturalWidth) return;
  const w = processed.naturalWidth, h = processed.naturalHeight;
  evidenceCanvas.width = w;evidenceCanvas.height = h;
  const ctx = evidenceCanvas.getContext("2d");
  if ($( "all-boxes" ).checked) {
    for (const [engine, branch] of Object.entries(result.results)) {
      if (branch.status !== "ok") continue;
      ctx.strokeStyle = engine === "classic" ? "#008778" : "#425edf";
      ctx.lineWidth = Math.max(2, w / 900);
      for (const line of branch.lines) if (line.box) {
        const [x1, y1, x2, y2] = line.box;
        ctx.strokeRect(x1, y1, x2 - x1, y2 - y1);
      }
    }
  }
  if (selectedEvidence?.anchor && selectedEvidence.anchor.join() !== selectedEvidence.box.join()) {
    const [x1, y1, x2, y2] = selectedEvidence.anchor;
    ctx.strokeStyle = "#d88614";ctx.fillStyle = "rgba(216,134,20,.13)";
    ctx.lineWidth = Math.max(4, w / 400);
    ctx.fillRect(x1, y1, x2 - x1, y2 - y1);
    ctx.strokeRect(x1, y1, x2 - x1, y2 - y1);
  }
  if (selectedEvidence?.box) {
    const [x1, y1, x2, y2] = selectedEvidence.box;
    ctx.strokeStyle = "#d72b4a";ctx.fillStyle = "rgba(215,43,74,.16)";
    ctx.lineWidth = Math.max(4, w / 400);
    ctx.fillRect(x1, y1, x2 - x1, y2 - y1);
    ctx.strokeRect(x1, y1, x2 - x1, y2 - y1);
  }
}
function focusEvidence(box, anchor = null) {
  if (!box) return;
  selectedEvidence = {box, anchor};drawEvidence();
  $("comparison").scrollIntoView({behavior:"smooth",block:"start"});
}
processed.addEventListener("load", drawEvidence);
$("all-boxes").addEventListener("change", drawEvidence);

function renderCard(engine) {
  const card = $(`${engine}-card`), branch = result.results[engine];
  card.replaceChildren(element("h3", engine === "classic" ? "A · Klassische OCR" : "B · Vision-Dokumentmodell"));
  if (branch.status !== "ok") {
    card.append(element("p", errorText[branch.error] || "Dieses Verfahren ist fehlgeschlagen.", "error"),
      element("p", `${(branch.elapsed_ms / 1000).toFixed(1)} s`, "meta"));
    return;
  }
  const automatic = branch.fields.filter(field => !suppressed[engine].has(field.code));
  card.append(element("p", `${branch.model} · ${(branch.elapsed_ms / 1000).toFixed(1)} s · ${branch.lines.length} Textbereiche · ${automatic.length} automatische Feldvorschläge`, "meta"));
  if (branch.layout_note) card.append(element("p", branch.layout_note, "note"));
  card.append(element("p", "Die Zuordnung ist ein Vorschlag. Orange markiert den gelesenen Feldcode, Rot den Wert. Falsche Vorschläge lassen sich verwerfen; der Rohtext bleibt erhalten.", "assignment-note"));
  card.append(element("h4", "Strukturierte Feldvorschläge"));
  const merged = new Map(automatic.map(field => [field.code, field]));
  for (const [code, field] of manual[engine]) merged.set(code, field);
  const priority = element("div", "", "priority-fields");
  priority.append(element("h5", "Wichtige Angaben"));
  for (const code of priorityCodes) {
    const field = merged.get(code);
    priority.append(element("span", `${code} ${fieldNames[code]}: ${field ? (field.manual ? "manuell" : reviewMethods.has(field.method) ? "prüfen" : "Vorschlag") : "offen"}`,
      `priority-item${field ? "" : " missing"}`));
  }
  card.append(priority);
  if (!merged.size) card.append(element("p", "Keine sicher belegbaren Felder. Rohtext prüfen und bei Bedarf manuell zuordnen.", "meta"));
  const fieldList = element("div", "", "field-list");
  for (const field of merged.values()) {
    const row = element("div", "", `field-item${reviewMethods.has(field.method) ? " needs-review" : ""}`);
    const show = element("button", "", "field-show");show.type = "button";
    const heading = element("span", "", "field-heading");
    heading.append(element("strong", field.code), element("small", fieldNames[field.code] || "Feldcode"));
    const method = field.manual ? "Manuell aus OCR-Text" :
      field.method === "adjacent_code" ? "Code und Wert in Nachbarboxen" :
      field.method === "below_caption" ? "Wert unter gedruckter Beschriftung" :
      field.method === "caption_region_next_line" ? "Nächste Textzeile derselben Layoutregion · bitte prüfen" :
      field.method === "surname_above_forename" ? "C.1.1-Code nicht gelesen · Wert oberhalb von C.1.2 · bitte prüfen" :
      field.method === "vl_table_adjacent_cell" ? "Benachbarte Modellzellen · grober Tabellenbeleg" :
      field.method === "vl_table_context_code" ? "Punkt im Feldcode fehlt · Tabellenfolge B/2.1/2.2 · bitte prüfen" :
      field.method === "merged_code" ? "Code und Wert verschmolzen · bitte prüfen" :
      "Code und Wert in einer Textzeile";
    show.append(heading, element("span", field.value, "field-value"), element("small", method, "field-method"));
    show.disabled = !field.box;
    show.addEventListener("click", () => focusEvidence(field.box, field.anchor_box));
    const dismiss = element("button", field.manual ? "Entfernen" : "Verwerfen", "field-dismiss");
    dismiss.type = "button";
    dismiss.setAttribute("aria-label", `${field.code} ${field.manual ? "entfernen" : "verwerfen"}`);
    dismiss.addEventListener("click", () => {
      if (field.manual) manual[engine].delete(field.code);
      else suppressed[engine].add(field.code);
      renderCard(engine);
    });
    row.append(show, dismiss);
    fieldList.append(row);
  }
  card.append(fieldList, element("h4", "Rohtext mit Bildbelegen"));
  if (!branch.lines.length) card.append(element("p", "Kein Text erkannt.", "meta"));
  const raw = element("div", "", "raw-lines");
  let code, lineSelect, value, form;
  branch.lines.forEach((line, index) => {
    const entry = element("div", "", "raw-entry");
    const row = element("button", "", "raw-line");row.type = "button";
    row.append(element("span", `${index + 1}.`), element("span", line.text));
    row.disabled = !line.box;
    row.title = line.source || "Bildbereich markieren";
    row.addEventListener("click", () => {
      lineSelect.value = String(index);value.value = line.text;
      focusEvidence(line.box);
    });
    const pick = element("button", "Zuordnen", "raw-pick");pick.type = "button";
    pick.disabled = !line.box;
    pick.addEventListener("click", () => {
      lineSelect.value = String(index);value.value = line.text;
      selectedEvidence = {box:line.box,anchor:null};drawEvidence();
      form.scrollIntoView({behavior:"smooth",block:"center"});code.focus();
    });
    entry.append(row,pick);raw.append(entry);
  });
  card.append(raw);
  if (!branch.lines.length) return;
  card.append(element("h4", "Zeile manuell zuordnen"));
  form = element("div", "", "manual");
  code = document.createElement("select");lineSelect = document.createElement("select");
  code.setAttribute("aria-label", "Feldcode");lineSelect.setAttribute("aria-label", "OCR-Zeile");
  code.append(new Option("Feldcode", ""));
  result.field_codes.forEach(fieldCode => code.append(new Option(`${fieldCode} · ${fieldNames[fieldCode] || "Feldcode"}`, fieldCode)));
  lineSelect.append(new Option("OCR-Zeile wählen", ""));
  branch.lines.forEach((row, index) => lineSelect.append(new Option(`${index + 1}: ${row.text.slice(0, 55)}`, String(index))));
  value = document.createElement("input");value.type = "text";value.maxLength = 500;
  value.setAttribute("aria-label", "Wörtlicher Ausschnitt aus der OCR-Zeile");
  value.placeholder = "OCR-Zeile wählen, dann bei Bedarf auf den Wert kürzen";
  lineSelect.addEventListener("change", () => {value.value = lineSelect.value === "" ? "" : branch.lines[Number(lineSelect.value)].text;});
  const add = element("button", "Zuordnen");add.type = "button";
  const hint = element("p", "Nur wörtlich erkannter Text mit Bildbereich ist zulässig.", "manual-hint");
  add.addEventListener("click", () => {
    const row = lineSelect.value === "" ? null : branch.lines[Number(lineSelect.value)];
    const chosen = value.value.trim();
    if (!code.value || !chosen || !row?.box || !row.text.includes(chosen)) {
      hint.textContent = "Feldcode und wörtlichen Ausschnitt aus der gewählten Zeile angeben.";
      hint.className = "manual-hint error";return;
    }
    manual[engine].set(code.value, {code:code.value,value:chosen,box:row.box,manual:true});
    suppressed[engine].delete(code.value);
    renderCard(engine);
  });
  const clear = element("button", "Manuelle Zuordnungen löschen");clear.type = "button";
  clear.addEventListener("click", () => {manual[engine].clear();renderCard(engine);});
  form.append(code,lineSelect,value,add,clear,hint);card.append(form);
}

run.addEventListener("click", async () => {
  const file = input.files?.[0];
  if (!file || !validCorners() || busy) return;
  if (file.size > 16 * 1048576) {setStatus(errorText.upload_too_large, "error");return;}
  const mime = file.type || (/\.jpe?g$/i.test(file.name) ? "image/jpeg" : /\.png$/i.test(file.name) ? "image/png" : "");
  if (!["image/jpeg", "image/png"].includes(mime)) {setStatus(errorText.unsupported_media_type, "error");return;}
  busy = true;updateControls();result = null;selectedEvidence = null;
  manual.classic.clear();manual.vision.clear();$("comparison").hidden = true;
  suppressed.classic.clear();suppressed.vision.clear();
  setStatus("Die lokalen Verfahren verarbeiten dasselbe Bild …");
  try {
    const geometry = {rotation:Number(rotation.value)};
    if (edited) geometry.corners = corners;
    const response = await fetch("/api/compare", {method:"POST",body:file,
      headers:{"Content-Type":mime,"X-OCR-Geometry":JSON.stringify(geometry),
        "X-OCR-Detail":finePrint.checked ? "fine" : "standard"},cache:"no-store"});
    const data = await response.json();
    if (!response.ok) {setStatus(errorText[data.error] || `Vergleich fehlgeschlagen (${response.status}).`,"error");return;}
    result = data;processed.src = data.image;
    $("image-size").textContent = `Gemeinsames OCR-Bild: ${data.image_size.width} × ${data.image_size.height} Pixel. Klick auf Wert oder Rohtext markiert seinen Bildbeleg.`;
    renderCard("classic");renderCard("vision");$("comparison").hidden = false;
    const both = Object.values(data.results).every(branch => branch.status === "ok");
    setStatus(both ? "Beide Ergebnisse bereit. Feldvorschläge anhand der Bildbelege prüfen." :
      "Ein Verfahren ist fehlgeschlagen; das andere Ergebnis und der Fehler sind sichtbar.",both ? "ok" : "error");
  } catch {
    setStatus(result ? "Die Antwort des lokalen Vergleichs konnte nicht angezeigt werden. Seite neu laden." :
      "Der lokale Dienst antwortet nicht. Prozess und /api/health prüfen.","error");
  } finally {busy = false;updateControls();}
});