const form = document.querySelector("#trialForm");
const statusEl = document.querySelector("#status");
const reportEl = document.querySelector("#report");
const emptyState = document.querySelector("#emptyState");
const headlineGrid = document.querySelector("#headlineGrid");
const summaryCard = document.querySelector("#summaryCard");
const actionList = document.querySelector("#actionList");
const compareTable = document.querySelector("#compareTable");
const examplesEl = document.querySelector("#examples");
const moduleList = document.querySelector("#moduleList");
const provenanceNote = document.querySelector("#provenanceNote");
const jsonOutput = document.querySelector("#jsonOutput");
const loadingState = document.querySelector("#loadingState");
const submitButton = form.querySelector('button[type="submit"]');
const sampleButton = document.querySelector("#sampleButton");
const clearButton = document.querySelector("#clearButton");

let latestReport = null;
let running = false;

const sample = {
  domain: "cancer",
  study_type: "INTERVENTIONAL",
  overall_status: "NOT_YET_RECRUITING",
  brief_title: "Remote Monitoring During Oncology Treatment",
  official_title:
    "A Randomized Phase 2 Trial of Remote Symptom Monitoring During Systemic Oncology Treatment",
  brief_summary:
    "This study evaluates whether remote symptom monitoring can improve follow-up completeness and early toxicity detection for adults receiving systemic oncology treatment.",
  conditions: "Cancer; treatment toxicity; remote monitoring",
  sponsor_name: "Example University Cancer Center",
  source_class: "OTHER",
  responsible_party_type: "SPONSOR",
  start_date: "2026-09-01",
  primary_completion_date: "2028-09-01",
  completion_date: "2029-03-01",
  phase: "PHASE2",
  primary_purpose: "TREATMENT",
  intervention_type: "BEHAVIORAL",
  intervention_model: "PARALLEL",
  allocation: "RANDOMIZED",
  masking: "NONE",
  enrollment: 420,
  enrollment_type: "ANTICIPATED",
  number_of_arms: 2,
  number_of_facilities: 12,
  number_of_primary_outcomes: 1,
  number_of_secondary_outcomes: 3,
  primary_outcome_title: "Completed follow-up assessment rate",
  primary_outcome_time_frame: "12 months",
  gender: "ALL",
  minimum_age_years: 18,
  maximum_age_years: "",
  has_dmc: false,
  has_us_facility: true,
  healthy_volunteers: false,
  ipd_sharing_plan: "UNDECIDED",
  criteria:
    "Inclusion Criteria: Adults with confirmed cancer diagnosis, planned systemic therapy, access to follow-up communication, and ability to complete patient-reported symptom assessments. Exclusion Criteria: inability to provide consent, concurrent investigational monitoring intervention, uncontrolled psychiatric or medical condition preventing follow-up, or enrollment in a conflicting trial.",
};

form.addEventListener("submit", async (event) => {
  event.preventDefault();
  // Guard: one request at a time. Blocks double-clicks / repeated Enter so we
  // never fire a duplicate (paid) LLM call for the same submit.
  if (running) return;
  running = true;
  setRunning(true);
  setStatus("Running");

  try {
    const response = await fetch("/api/report", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify(readForm()),
    });
    const report = await response.json();
    latestReport = report;
    renderReport(report);
    setStatus(report.ok ? "Complete" : "Needs Input", !report.ok);
  } catch (error) {
    latestReport = { ok: false, error: error.message };
    renderReport(latestReport);
    setStatus("Error", true);
  } finally {
    running = false;
    setRunning(false);
  }
});

function setRunning(on) {
  submitButton.disabled = on;
  sampleButton.disabled = on;
  clearButton.disabled = on;
  submitButton.innerHTML = on
    ? '<span class="btn-spinner" aria-hidden="true"></span>Running…'
    : "Run Preflight";
  if (on) {
    emptyState.classList.add("hidden");
    reportEl.classList.add("hidden");
    loadingState.classList.remove("hidden");
  } else {
    loadingState.classList.add("hidden");
  }
}

document.querySelector("#sampleButton").addEventListener("click", () => {
  writeForm(sample);
  setStatus("Sample Loaded");
});

document.querySelector("#clearButton").addEventListener("click", () => {
  form.reset();
  hideReport();
  setStatus("Ready");
});

document.querySelector("#copyButton").addEventListener("click", async () => {
  if (!latestReport) return;
  await navigator.clipboard.writeText(JSON.stringify(latestReport, null, 2));
  setStatus("Copied");
});

function readForm() {
  const data = Object.fromEntries(new FormData(form).entries());
  for (const key of ["has_dmc", "has_us_facility", "healthy_volunteers"]) {
    data[key] = form.elements[key].checked;
  }
  return data;
}

function writeForm(values) {
  for (const [key, value] of Object.entries(values)) {
    const field = form.elements[key];
    if (!field) continue;
    if (field.type === "checkbox") field.checked = Boolean(value);
    else field.value = value;
  }
}

function renderReport(report) {
  emptyState.classList.add("hidden");
  reportEl.classList.remove("hidden");
  jsonOutput.textContent = JSON.stringify(report, null, 2);

  if (!report.ok) {
    renderErrorState(report);
    return;
  }

  const output = report.final_output;
  const evidence = report.historical_evidence;

  renderHeadline(output.headline);
  renderSummary(output);
  renderActions(output.actions);
  renderCompare(output.key_numbers);
  renderExamples(evidence.examples);
  renderModules(output.module_statuses);
  provenanceNote.textContent = output.model_status || "";
}

function renderErrorState(report) {
  headlineGrid.innerHTML = "";
  compareTable.innerHTML = "";
  examplesEl.innerHTML = "";
  moduleList.innerHTML = "";
  provenanceNote.textContent = "";
  summaryCard.replaceChildren(paragraph("The protocol entry is incomplete — fix the items below and run again."));
  const errors =
    report.trial_feature_profile?.validation?.errors || [report.error || "Report failed."];
  actionList.innerHTML = "";
  for (const err of errors) {
    actionList.appendChild(actionItem({ severity: "review", text: err }));
  }
}

/* ---------- tier 1 ---------- */
function renderHeadline(items) {
  headlineGrid.innerHTML = "";
  for (const item of items || []) {
    const card = document.createElement("div");
    card.className = `stat tone-${item.tone || "neutral"}`;
    card.innerHTML = `
      <div class="stat-label"></div>
      <div class="stat-value"></div>
      <div class="stat-sub"></div>
      <span class="chip"></span>`;
    card.querySelector(".stat-label").textContent = item.label;
    card.querySelector(".stat-value").textContent = item.value ?? "NA";
    card.querySelector(".stat-sub").textContent = item.sub || "";
    card.querySelector(".chip").textContent = item.provenance || "";
    headlineGrid.appendChild(card);
  }
}

/* ---------- tier 2 ---------- */
function renderSummary(output) {
  summaryCard.innerHTML = "";

  if (output.takeaway) {
    const lead = document.createElement("p");
    lead.className = "takeaway";
    lead.textContent = output.takeaway;
    summaryCard.appendChild(lead);
  }
  for (const line of output.summary || []) {
    summaryCard.appendChild(paragraph(line));
  }

  if (output.summary_warning) {
    const warn = document.createElement("p");
    warn.className = "summary-source";
    warn.textContent = output.summary_warning;
    summaryCard.appendChild(warn);
  }
}

function renderActions(actions) {
  actionList.innerHTML = "";
  for (const action of actions || []) {
    actionList.appendChild(actionItem(action));
  }
}

function actionItem(action) {
  const li = document.createElement("li");
  li.className = `action sev-${action.severity || "review"}`;
  const marker = document.createElement("span");
  marker.className = "marker";
  const text = document.createElement("span");
  text.className = "text";
  text.textContent = action.text;
  const tag = document.createElement("span");
  tag.className = "tag";
  tag.textContent = { review: "design", completeness: "fill-in", ok: "ok" }[action.severity] || "note";
  li.append(marker, text, tag);
  return li;
}

/* ---------- tier 3 ---------- */
function renderCompare(numbers) {
  const rows = [
    ["Enrollment", numbers.planned_enrollment, numbers.comparator_median_enrollment],
    ["Facilities", numbers.planned_facilities, numbers.comparator_median_facilities],
    ["Arms", numbers.planned_arms, numbers.comparator_median_arms],
    ["Primary outcomes", numbers.planned_primary_outcomes, numbers.comparator_median_primary_outcomes],
    ["Secondary outcomes", numbers.planned_secondary_outcomes, numbers.comparator_median_secondary_outcomes],
  ];
  let body = "";
  for (const [label, planned, median] of rows) {
    body += `<tr><td>${label}</td><td class="num">${fmt(planned)}</td><td class="num">${fmt(median)}</td><td class="num">${ratio(planned, median)}</td></tr>`;
  }
  compareTable.innerHTML = `
    <thead><tr>
      <th>Metric</th><th class="num">Your plan</th><th class="num">Comparator median</th><th class="num">Ratio</th>
    </tr></thead>
    <tbody>${body}</tbody>`;
}

function renderExamples(examples) {
  if (!examples || !examples.length) {
    examplesEl.textContent = "No comparator examples returned.";
    return;
  }
  const rows = examples
    .map(
      (e) => `<tr>
        <td>${e.nct_id ?? "NA"}</td>
        <td>${e.brief_title ?? "NA"}</td>
        <td>${e.phase ?? "NA"}</td>
        <td class="num">${fmt(e.enrollment)}</td>
        <td class="num">${fmt(e.arms)}</td>
        <td class="${e.published ? "pub-yes" : "pub-no"}">${e.published ? "Yes" : "No"}</td>
      </tr>`
    )
    .join("");
  const table = document.createElement("table");
  table.className = "example-table";
  table.innerHTML = `
    <thead><tr>
      <th>NCT ID</th><th>Title</th><th>Phase</th><th class="num">Enrollment</th><th class="num">Arms</th><th>Published</th>
    </tr></thead><tbody>${rows}</tbody>`;
  const wrap = document.createElement("div");
  wrap.className = "table-scroll";
  wrap.appendChild(table);
  examplesEl.replaceChildren(wrap);
}

function renderModules(modules) {
  moduleList.innerHTML = "";
  for (const [name, d] of Object.entries(modules || {})) {
    const item = document.createElement("div");
    item.className = "module-item";
    const title = document.createElement("strong");
    title.textContent = name.replaceAll("_", " ");
    const badge = document.createElement("span");
    badge.className = `sel-badge sel-${d.selection || "primary"}`;
    badge.textContent = d.selection || "primary";
    const meta = document.createElement("span");
    meta.className = "meta";
    meta.textContent = `${d.capability || ""} · ${d.language || "?"} · ${d.status || "?"}`;
    const desc = document.createElement("p");
    desc.textContent = d.selection === "skipped" && d.reason ? d.reason : d.description || "";
    item.append(title, badge, meta, desc);
    moduleList.appendChild(item);
  }
}

/* ---------- helpers ---------- */
function hideReport() {
  reportEl.classList.add("hidden");
  emptyState.classList.remove("hidden");
  latestReport = null;
}

function setStatus(text, isError = false) {
  statusEl.textContent = text;
  statusEl.classList.toggle("error", isError);
}

function paragraph(text) {
  const p = document.createElement("p");
  p.textContent = text;
  return p;
}

function fmt(value) {
  if (value === null || value === undefined || value === "") return "NA";
  return value;
}

function ratio(planned, median) {
  const a = Number(planned);
  const b = Number(median);
  if (!a || !b) return "—";
  const r = a / b;
  const cls = r >= 1.5 ? "delta-high" : r <= 0.67 ? "delta-low" : "";
  return `<span class="${cls}">${r.toFixed(2)}×</span>`;
}

writeForm(sample);