/* ============================================================================
   FALSIFY live UI — force-graph rendering, SSE stream, and the four signature
   animations that make "revised, not forgotten" visible:

     • strike   — a refuted node flashes red and gains a dashed-red border
     • sweep    — invalidation greys downstream nodes with a staggered delay
     • dissolve — a forgotten node shrinks to nothing, then is removed
     • rise     — a promoted / newly-added node pulses green and settles

   State is never carried by color alone (green↔red are close under deuteranopia):
   every node draws its truth-state color AND a text label AND — when refuted — a
   dashed border, and every change is narrated in the revision log.
   ========================================================================== */

const API = window.__API_BASE__ || "";           // "" = same-origin (HF monolith)
const $ = (id) => document.getElementById(id);

const STATE = {
  alive:       { color: "#22c55e", tag: "alive" },
  refuted:     { color: "#ef4444", tag: "refuted" },
  invalidated: { color: "#9ca3af", tag: "invalidated" },
  superseded:  { color: "#f59e0b", tag: "superseded" },
  forgotten:   { color: "#4b5563", tag: "forgotten" },
};
const colorOf = (s) => (STATE[s] || STATE.alive).color;

/* ------------------------------------------------------------------ graph state */
let Graph;                         // the force-graph instance
let nodes = [];                    // {id,label,type,state,color, _flash,_flashColor,_shrink,_born}
let links = [];                    // {source,target,relation, _pulse}
const byId = () => Object.fromEntries(nodes.map((n) => [n.id, n]));

/* animation timers tick every frame; the renderer reads them */
function tickAnimations() {
  let alive = false;
  for (const n of nodes) {
    if (n._flash > 0) { n._flash = Math.max(0, n._flash - 0.018); alive = true; }
    if (n._shrink > 0) { n._shrink = Math.min(1, n._shrink + 0.04); alive = true; }
    if (n._born > 0) { n._born = Math.max(0, n._born - 0.02); alive = true; }
  }
  for (const l of links) {
    if (l._pulse > 0) { l._pulse = Math.max(0, l._pulse - 0.03); alive = true; }
  }
  // drop fully-dissolved nodes
  const gone = nodes.filter((n) => n._shrink >= 1).map((n) => n.id);
  if (gone.length) removeNodes(gone);
  if (alive && Graph) Graph.nodeRelSize(Graph.nodeRelSize()); // nudge a redraw
  requestAnimationFrame(tickAnimations);
}

/* ------------------------------------------------------------------ rendering */
function drawNode(node, ctx, scale) {
  const base = 6;
  const grow = node._born > 0 ? 1 + node._born * 0.4 : 1;      // "rise" scale-in
  const shrink = node._shrink > 0 ? 1 - node._shrink : 1;       // "dissolve" scale-out
  const r = base * grow * shrink;
  if (r <= 0.2) return;

  const isRefuted = node.state === "refuted";
  const alpha = shrink;

  ctx.globalAlpha = alpha;

  // soft state glow so the canvas feels alive
  ctx.beginPath();
  ctx.arc(node.x, node.y, r + 5, 0, 2 * Math.PI);
  ctx.fillStyle = hexA(node.color, 0.12);
  ctx.fill();

  // node body
  ctx.beginPath();
  ctx.arc(node.x, node.y, r, 0, 2 * Math.PI);
  ctx.fillStyle = node.color;
  ctx.fill();

  // refuted = dashed red ring (the second channel, so it's not color-only)
  if (isRefuted) {
    ctx.setLineDash([3, 2]);
    ctx.strokeStyle = "#ef4444";
    ctx.lineWidth = 1.6 / scale;
    ctx.stroke();
    ctx.setLineDash([]);
  } else {
    ctx.strokeStyle = "#0b1020";
    ctx.lineWidth = 1.4 / scale;
    ctx.stroke();
  }

  // flash ring (strike / state-change / rise)
  if (node._flash > 0) {
    ctx.beginPath();
    ctx.arc(node.x, node.y, r + 4 + (1 - node._flash) * 8, 0, 2 * Math.PI);
    ctx.strokeStyle = hexA(node._flashColor || node.color, node._flash);
    ctx.lineWidth = 2.4 / scale;
    ctx.stroke();
  }

  // label — always present (identity never color-alone)
  const label = node.label.length > 34 ? node.label.slice(0, 31) + "…" : node.label;
  const fs = Math.max(3.2, 11 / scale);
  ctx.font = `${fs}px Inter, sans-serif`;
  ctx.textAlign = "center";
  ctx.textBaseline = "top";
  ctx.fillStyle = "#cbd5e1";
  ctx.globalAlpha = alpha * 0.9;
  ctx.fillText(label, node.x, node.y + r + 2);
  ctx.globalAlpha = 1;
}

function drawLink(link, ctx, scale) {
  const s = link.source, t = link.target;
  if (!s || !t || typeof s !== "object") return;
  ctx.beginPath();
  ctx.moveTo(s.x, s.y);
  ctx.lineTo(t.x, t.y);
  if (link._pulse > 0) {
    ctx.strokeStyle = hexA("#34d399", link._pulse);
    ctx.lineWidth = 2.4 / scale;
  } else {
    ctx.strokeStyle = "rgba(148,163,184,.28)";
    ctx.lineWidth = 1 / scale;
  }
  ctx.stroke();
}

function initGraph() {
  Graph = ForceGraph()($("graph"))
    .backgroundColor("rgba(0,0,0,0)")
    .nodeRelSize(6)
    .nodeCanvasObject(drawNode)
    .nodePointerAreaPaint((node, color, ctx) => {
      ctx.fillStyle = color; ctx.beginPath();
      ctx.arc(node.x, node.y, 9, 0, 2 * Math.PI); ctx.fill();
    })
    .linkCanvasObject(drawLink)
    .linkDirectionalArrowLength(2.5)
    .onNodeHover((n) => ($("graph").style.cursor = n ? "pointer" : "default"))
    .onNodeClick((n) => addMessage("system", nodeCard(n)))
    .cooldownTicks(120)
    .d3VelocityDecay(0.28);
  sizeGraph();
  window.addEventListener("resize", sizeGraph);
}
function sizeGraph() {
  const el = $("graph-panel");
  Graph.width(el.clientWidth).height(el.clientHeight);
}

/* ------------------------------------------------------------------ graph data ops */
function setGraph(g) {
  const prev = byId();
  nodes = g.nodes.map((n) => ({
    ...n,
    _flash: prev[n.id] ? 0 : 0.9,       // new nodes "rise"
    _flashColor: "#22c55e",
    _born: prev[n.id] ? 0 : 1,
    _shrink: 0,
    x: prev[n.id]?.x, y: prev[n.id]?.y, // keep positions stable across refetches
  }));
  const idset = new Set(nodes.map((n) => n.id));
  links = g.edges
    .filter((e) => idset.has(e.source) && idset.has(e.target))
    .map((e) => ({ source: e.source, target: e.target, relation: e.relation, _pulse: 0 }));
  Graph.graphData({ nodes, links });
  updateBackendUI(g.backend, g.scenario);
}

function removeNodes(ids) {
  const set = new Set(ids);
  nodes = nodes.filter((n) => !set.has(n.id));
  links = links.filter((l) => {
    const s = typeof l.source === "object" ? l.source.id : l.source;
    const t = typeof l.target === "object" ? l.target.id : l.target;
    return !set.has(s) && !set.has(t);
  });
  Graph.graphData({ nodes, links });
}

async function refetchGraph() {
  const g = await fetch(`${API}/api/graph`).then((r) => r.json());
  setGraph(g);
}

/* ------------------------------------------------------------------ SSE events */
function connectSSE() {
  const es = new EventSource(`${API}/api/events`);
  es.onopen = () => setConn("live", "live");
  es.onerror = () => { setConn("reconnecting", "reconnecting…"); };
  es.onmessage = (e) => {
    let ev; try { ev = JSON.parse(e.data); } catch { return; }
    handleEvent(ev);
  };
}

function handleEvent(ev) {
  const map = byId();
  if (ev.type === "graph_reset") {
    refetchGraph();
  } else if (ev.type === "node_state_changed") {
    const n = map[ev.id];
    if (!n) return;
    n.state = ev.state;
    n.color = colorOf(ev.state);
    n._flash = 1.0;
    n._flashColor = colorOf(ev.state);
    // light up edges INTO this node so the cascade visibly travels
    for (const l of links) {
      const t = typeof l.target === "object" ? l.target.id : l.target;
      if (t === ev.id) l._pulse = 1.0;
    }
    logEntry(ev.state, n.label, ev.id, whyFor(ev.state));
  } else if (ev.type === "node_forgotten") {
    const n = map[ev.id];
    if (n) { n._shrink = 0.01; logEntry("forgotten", n.label, ev.id, whyFor("forgotten")); }
  } else if (ev.type === "pipeline_step") {
    addMessage("system", `<div class="msg-title">${escapeHtml(ev.step)}</div>${escapeHtml(ev.detail || "")}`);
  }
}

const WHY = {
  refuted:     "contradicted by the incoming fact",
  invalidated: "its critical support died",
  superseded:  "its evidence collapsed; a rival now leads",
  forgotten:   "orphaned — no live consumer (provenance kept)",
  alive:       "promoted — still standing",
};
const whyFor = (s) => WHY[s] || "";

/* ------------------------------------------------------------------ panels */
function addMessage(kind, html, warn) {
  const div = document.createElement("div");
  div.className = `msg ${kind}${warn ? " warn" : ""}`;
  div.innerHTML = html;
  $("messages").appendChild(div);
  $("messages").scrollTop = $("messages").scrollHeight;
  $("msg-count").textContent = $("messages").querySelectorAll(".msg").length + " msgs";
  clearCoach();
}
function clearCoach() { const c = document.querySelector(".coach"); if (c) c.remove(); }

function nodeCard(n) {
  return `<div class="msg-title">${escapeHtml(n.label)}</div>
    <div class="msg-meta">${n.type} · <span style="color:${n.color}">${STATE[n.state]?.tag || n.state}</span> · ${n.id.slice(0,8)}</div>`;
}

function logEntry(state, label, id, why) {
  const wrap = $("log");
  const row = document.createElement("div");
  row.className = "log-entry";
  row.innerHTML = `<span class="log-dot" style="background:${colorOf(state)}"></span>
    <div class="log-body">
      <div class="lg-title">${escapeHtml(shortLabel(label))}
        <span class="id">${state}</span></div>
      <div class="lg-why">${escapeHtml(why)}</div>
    </div>`;
  wrap.prepend(row);
  $("log-count").textContent = wrap.querySelectorAll(".log-entry").length + " events";
}

function renderScoreboard(sb) {
  if (!sb) return;
  $("sb-q").textContent = sb.question || "";
  $("falsify-answer").textContent = sb.falsify_answer || "—";
  $("falsify-support").textContent = (sb.falsify_support || []).length
    ? "supported by: " + sb.falsify_support.join(", ") : "";
  $("rag-answer").textContent = sb.rag_answer || "—";
  const ragCard = $("rag-card");
  if (sb.stale) {
    $("rag-note").textContent = "⚠ still cites a node FALSIFY refuted — a stale answer.";
    ragCard.classList.add("stale");
    ragCard.classList.remove("stale-flash"); void ragCard.offsetWidth;
    ragCard.classList.add("stale-flash");
  } else {
    $("rag-note").textContent = sb.rag_citations?.length ? "cites: " + sb.rag_citations[0] : "";
    ragCard.classList.remove("stale");
  }
}

/* ------------------------------------------------------------------ actions */
async function sendMessage() {
  const input = $("msg-input");
  const msg = input.value.trim();
  if (!msg) return;
  addMessage("user", escapeHtml(msg));
  input.value = ""; autoGrow();
  $("send-btn").disabled = true;
  try {
    const res = await fetch(`${API}/api/chat`, {
      method: "POST", headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ message: msg, demo: true }),
    }).then((r) => r.json());
    if (res.type === "answer") { renderScoreboard(res.data); addMessage("system", "Answered from the alive belief graph — see the scoreboard."); }
    else if (res.type === "revision") { summarizeRevision(res.data); await afterRevision(); }
  } catch (e) { addMessage("system", "Request failed: " + escapeHtml(String(e)), true); }
  $("send-btn").disabled = false;
}

function summarizeRevision(d) {
  if (!d.revised) { addMessage("system", "No contradiction found — the graph is unchanged."); return; }
  const pill = (t, c) => `<span class="pill" style="background:${c}22;color:${c}">${t}</span>`;
  addMessage("system",
    `<div class="msg-title">Belief revised</div>
     ${pill(d.refuted.length + " refuted", "#ef4444")}
     ${pill(d.invalidated.length + " invalidated", "#9ca3af")}
     ${pill(d.forgotten.length + " forgotten", "#4b5563")}
     <div class="msg-meta">epoch ${d.epoch} · provenance retained: ${d.retained_provenance.length}</div>`);
}

async function afterRevision() {
  const sb = await fetch(`${API}/api/scoreboard`).then((r) => r.json());
  renderScoreboard(sb);
}

async function runDemo() {
  clearCoach();
  addMessage("system", `<div class="msg-title">Running investigation…</div>watch the graph revise in real time.`);
  const res = await fetch(`${API}/api/demo`, { method: "POST" }).then((r) => r.json());
  summarizeRevision(res.report);
  renderScoreboard(res.scoreboard);
}

async function runDiamond() {
  clearCoach();
  addMessage("system", `<div class="msg-title">Diamond scenario</div>K2 rests on two supports — watch it survive one blow, then fall to the second.`);
  const res = await fetch(`${API}/api/diamond`, { method: "POST" }).then((r) => r.json());
  addMessage("system", "Phase 1 done — K died, K2 survived. Phase 2 done — K2 collapsed.");
  renderScoreboard(res.scoreboard);
}

async function setScenario(kind) {
  const g = await fetch(`${API}/api/scenario`, {
    method: "POST", headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ kind }),
  }).then((r) => r.json());
  setGraph(g);
  addMessage("system", `Loaded the ${kind} investigation — ${g.nodes.length} beliefs.`);
}

async function resetGraph() { const g = await fetch(`${API}/api/reset`, { method: "POST" }).then((r) => r.json()); setGraph(g); addMessage("system", "Graph reset."); }

async function verifyPersistence() {
  addMessage("system", "Re-reading belief state from the on-disk graph store…");
  const res = await fetch(`${API}/api/verify`).then((r) => r.json());
  if (!res.persisted) { addMessage("system", "Could not read persisted state: " + escapeHtml(res.error || ""), true); return; }
  const lines = Object.entries(res.summary || {})
    .map(([t, c]) => `${t}: ${Object.entries(c).map(([s, n]) => `${n} ${s}`).join(", ")}`).join("<br>");
  addMessage("system", `<div class="msg-title">✓ Beliefs are persisted on the graph</div>${lines}<div class="msg-meta">truth-state lives in storage, not in process memory.</div>`);
}

async function uploadFile(file) {
  addMessage("user", `📄 ${escapeHtml(file.name)}`);
  addMessage("system", "Ingesting into memory (add + cognify)…");
  const fd = new FormData(); fd.append("file", file);
  const res = await fetch(`${API}/api/upload`, { method: "POST", body: fd }).then((r) => r.json());
  if (res.ok) { setGraph(res.graph); addMessage("system", "Ingested — new evidence is now in the graph."); }
  else { addMessage("system", (res.error || "upload failed") + (res.hint ? `<div class="msg-meta">${res.hint}</div>` : ""), true); }
}

async function setBackend(mode) {
  const res = await fetch(`${API}/api/mode`, {
    method: "POST", headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ mode }),
  }).then((r) => r.json());
  updateBackendUI(res.backend);
  addMessage("system", res.backend === "cloud"
    ? "Backend → Cognee Cloud. All memory ops now run on the tenant."
    : "Backend → self-hosted (open source).");
}

/* ------------------------------------------------------------------ ui helpers */
function updateBackendUI(backend, scenario) {
  if (backend) {
    document.querySelectorAll("#backend-toggle button").forEach((b) =>
      b.classList.toggle("on", b.dataset.mode === backend));
  }
}
function setConn(cls, label) {
  const el = $("conn"); el.className = "status-dot " + cls;
  $("conn-label").textContent = label;
}
function autoGrow() { const t = $("msg-input"); t.style.height = "auto"; t.style.height = Math.min(120, t.scrollHeight) + "px"; }
function shortLabel(s) { return s.length > 40 ? s.slice(0, 37) + "…" : s; }
function escapeHtml(s) { return String(s).replace(/[&<>"']/g, (c) => ({ "&": "&amp;", "<": "&lt;", ">": "&gt;", '"': "&quot;", "'": "&#39;" }[c])); }
function hexA(hex, a) {
  const h = hex.replace("#", "");
  const n = parseInt(h.length === 3 ? h.split("").map((x) => x + x).join("") : h, 16);
  return `rgba(${(n >> 16) & 255},${(n >> 8) & 255},${n & 255},${a})`;
}

/* ------------------------------------------------------------------ wire up */
function wire() {
  $("send-btn").onclick = sendMessage;
  $("msg-input").addEventListener("keydown", (e) => {
    if (e.key === "Enter" && !e.shiftKey) { e.preventDefault(); sendMessage(); }
  });
  $("msg-input").addEventListener("input", autoGrow);
  $("btn-run").onclick = runDemo;
  $("btn-simple").onclick = () => setScenario("simple");
  $("btn-diamond").onclick = runDiamond;
  $("btn-reset").onclick = resetGraph;
  $("btn-verify").onclick = verifyPersistence;
  document.querySelectorAll("#backend-toggle button").forEach((b) =>
    (b.onclick = () => setBackend(b.dataset.mode)));

  const dz = $("dropzone"), fi = $("file-input");
  fi.onchange = () => fi.files[0] && uploadFile(fi.files[0]);
  ["dragover", "dragenter"].forEach((ev) => dz.addEventListener(ev, (e) => { e.preventDefault(); dz.classList.add("drag"); }));
  ["dragleave", "drop"].forEach((ev) => dz.addEventListener(ev, (e) => { e.preventDefault(); dz.classList.remove("drag"); }));
  dz.addEventListener("drop", (e) => { const f = e.dataTransfer.files[0]; if (f) uploadFile(f); });

  // coach mark
  $("messages").innerHTML = `<div class="coach">Hit <b>▶ Run investigation</b> to watch a belief die — or drop a contradicting fact of your own.</div>`;
}

async function boot() {
  wire();
  initGraph();
  requestAnimationFrame(tickAnimations);
  connectSSE();
  try { await refetchGraph(); } catch { addMessage("system", "Backend not reachable yet — retrying via events.", true); }
}
boot();