"use strict";
// Browser client for Magicka VM. The browser only ever sends INTENT; the server
// is the sole authority. This file mirrors the `protocol` crate's wire format
// (version 1, envelope {v,type,body}). It never simulates the world — it renders
// exactly what the server says is observable.

const PROTOCOL_VERSION = 1;
const OPS = ["mix","channel","branch","schedule","resonate","observe",
             "collapse","invert","diffuse","anchor","echoback","imprint"];

const state = {
  ws: null,
  playerId: null,
  matchId: null,
  turn: 0,
  deadline: 0,
  locked: false,
  snapshot: null,
  selectedTarget: null,
  program: [],
  slots: [[], [], []],
  activeSlot: 0,
  liveHashes: {},      // turn -> runtime_hash seen live
  replay: null,        // { turns: [...], final_hash, cursor }
};

// ---- wire helpers -------------------------------------------------------
function send(type, body) {
  if (!state.ws || state.ws.readyState !== WebSocket.OPEN) return;
  state.ws.send(JSON.stringify({ v: PROTOCOL_VERSION, type, body }));
}

function connect() {
  const proto = location.protocol === "https:" ? "wss" : "ws";
  const ws = new WebSocket(`${proto}://${location.host}/ws`);
  state.ws = ws;
  ws.onopen = () => {
    setConn(true);
    send("JoinMatch", { name: "dev-" + Math.floor(Math.random() * 1000), match_id: null });
  };
  ws.onclose = () => { setConn(false); setTimeout(connect, 1000); };
  ws.onerror = () => ws.close();
  ws.onmessage = (ev) => {
    let msg;
    try { msg = JSON.parse(ev.data); } catch (_) { return; }
    if (!msg || msg.v !== PROTOCOL_VERSION) return;
    handle(msg.type, msg.body || {});
  };
}

function setConn(on) {
  const el = document.getElementById("conn");
  el.textContent = on ? "connected" : "disconnected";
  el.className = "badge " + (on ? "on" : "off");
}

// ---- server message handling -------------------------------------------
function handle(type, body) {
  switch (type) {
    case "MatchState":
      state.playerId = body.player_id;
      state.matchId = body.match_id;
      state.turn = body.turn;
      state.snapshot = body.snapshot;
      render();
      break;
    case "TurnStarted":
      state.turn = body.turn;
      state.deadline = Date.now() + (body.deadline_ms || 0);
      state.locked = false;
      renderTimer();
      break;
    case "TurnResolved":
      state.turn = body.turn;
      state.snapshot = body.snapshot;
      state.liveHashes[body.turn] = body.runtime_hash;
      (body.events || []).forEach((e) => log(`t${body.turn}: ${e}`));
      showHashes();
      render();
      break;
    case "ObservationResult":
      renderDiagnostics(body.diagnostics, `target ${body.target}`);
      break;
    case "ValidationReport":
      log((body.accepted ? "✓ " : "✗ ") + body.detail);
      if (body.diagnostics) renderDiagnostics(body.diagnostics, "program");
      break;
    case "ReplayChunk":
      loadReplay(body);
      break;
    case "ErrorEvent":
      log(`! ${body.code}: ${body.detail}`);
      break;
  }
}

// ---- rendering ----------------------------------------------------------
function render() {
  if (!state.snapshot) return;
  renderArena();
  renderDomains();
  renderLogHistory();
  renderTimer();
}

function renderArena() {
  const s = state.snapshot;
  const arena = document.getElementById("arena");
  arena.style.gridTemplateColumns = `repeat(${s.arena_w}, 34px)`;
  arena.innerHTML = "";
  const at = {};
  (s.observed_entities || []).forEach((e) => { at[`${e.x},${e.y}`] = e; });
  for (let y = 0; y < s.arena_h; y++) {
    for (let x = 0; x < s.arena_w; x++) {
      const cell = document.createElement("div");
      cell.className = "cell";
      const e = at[`${x},${y}`];
      if (e) {
        cell.textContent = e.is_self ? "@" : (e.is_dummy ? "▣" : "&");
        if (e.is_self) cell.classList.add("self");
        if (state.selectedTarget === e.id) cell.classList.add("target");
        if (!e.alive) cell.classList.add("dead");
        const hp = document.createElement("span");
        hp.className = "hp"; hp.textContent = e.hp;
        cell.appendChild(hp);
        cell.title = `${e.name} (#${e.id}) hp ${e.hp}`;
        cell.onclick = () => { state.selectedTarget = e.id; renderArena(); };
      }
      arena.appendChild(cell);
    }
  }
}

function renderDomains() {
  const s = state.snapshot;
  const wrap = document.getElementById("domains");
  wrap.innerHTML = "";
  (s.observed_domains || []).forEach((d) => {
    const el = document.createElement("div");
    el.className = "domain";
    const name = document.createElement("div");
    name.className = "name"; name.textContent = `${d.index}: ${d.name}`;
    el.appendChild(name);
    d.observed.forEach((v, i) => {
      const lane = document.createElement("span");
      const k = (d.knowledge && d.knowledge[i]) || "unknown";
      lane.className = "lane " + k;
      lane.textContent = v === null ? "▒" : v;
      lane.title = k;
      el.appendChild(lane);
    });
    wrap.appendChild(el);
  });
  document.getElementById("redactions").textContent =
    `${s.hidden_state_redactions} hidden state values withheld (hidden lanes + masked observations)`;
  const inf = document.getElementById("inferred");
  inf.innerHTML = "";
  (s.inferred_markers || []).forEach((m) => {
    const li = document.createElement("li"); li.textContent = m; inf.appendChild(li);
  });
}

function renderLogHistory() {
  // History from the snapshot is authoritative; live events are appended too.
  const known = state.snapshot.known_history || [];
  const log = document.getElementById("log");
  if (log.dataset.lastTurn !== String(state.turn)) {
    log.dataset.lastTurn = String(state.turn);
  }
}

function renderTimer() {
  const t = document.getElementById("timer");
  const remain = Math.max(0, Math.ceil((state.deadline - Date.now()) / 1000));
  t.textContent = `turn ${state.turn} — ${remain}s ${state.locked ? "(locked)" : ""}`;
}
setInterval(() => {
  if (state.deadline) {
    if (Date.now() > state.deadline) state.locked = true;
    renderTimer();
  }
}, 250);

function renderDiagnostics(d, label) {
  const body = document.getElementById("diag-body");
  body.innerHTML = "";
  const row = (k, v) => {
    const div = document.createElement("div");
    div.className = "diag-row";
    div.innerHTML = `<span class="diag-key">${k}:</span> ${v}`;
    body.appendChild(div);
  };
  row("for", label);
  row("known reads", (d.known_reads || []).join(", ") || "—");
  row("known writes", (d.known_writes || []).join(", ") || "—");
  row("observed risks", (d.observed_risks || []).join(", ") || "none observed");
  row("unknown listeners", `<span class="warn">${d.unknown_listeners || 0}</span> (writes you cannot observe)`);
  row("previous outcomes", (d.previous_outcomes || []).join(" | ") || "—");
}

// ---- rune editor --------------------------------------------------------
function renderTokens() {
  const wrap = document.getElementById("tokens");
  wrap.innerHTML = "";
  state.program.forEach((t, i) => {
    const el = document.createElement("span");
    el.className = "token";
    el.textContent = `${OPS[t.op % OPS.length]} ${t.a},${t.b},${t.c}#${t.imm}`;
    el.title = "click to remove";
    el.onclick = () => { state.program.splice(i, 1); renderTokens(); };
    wrap.appendChild(el);
  });
}

function renderLibrary() {
  const wrap = document.getElementById("library");
  wrap.innerHTML = "";
  state.slots.forEach((slot, i) => {
    const el = document.createElement("div");
    el.className = "slot" + (i === state.activeSlot ? " active" : "");
    el.textContent = `slot ${i + 1} (${slot.length})`;
    el.onclick = () => {
      state.slots[state.activeSlot] = state.program.slice();
      state.activeSlot = i;
      state.program = state.slots[i].slice();
      renderTokens(); renderLibrary();
    };
    wrap.appendChild(el);
  });
}

function initEditor() {
  const sel = document.getElementById("op-select");
  OPS.forEach((op, i) => {
    const o = document.createElement("option");
    o.value = i; o.textContent = op; sel.appendChild(o);
  });
  document.getElementById("btn-add").onclick = () => {
    state.program.push({
      op: parseInt(sel.value, 10),
      a: clampByte("tok-a"), b: clampByte("tok-b"), c: clampByte("tok-c"),
      imm: parseInt(document.getElementById("tok-imm").value, 10) || 0,
    });
    renderTokens();
  };
  document.getElementById("btn-clear").onclick = () => { state.program = []; renderTokens(); };
  document.getElementById("btn-save").onclick = () => {
    send("EditRuneProgram", { tokens: state.program });
    log("saved program (" + state.program.length + " runes)");
  };
  renderTokens(); renderLibrary();
}

function clampByte(id) {
  let v = parseInt(document.getElementById(id).value, 10) || 0;
  return Math.max(0, Math.min(255, v));
}

// ---- actions ------------------------------------------------------------
function submit(action) {
  if (state.locked) { log("turn locked — submission rejected client-side"); return; }
  send("SubmitTurn", { turn: state.turn, action });
}

function initActions() {
  document.querySelectorAll("[data-move]").forEach((b) => {
    b.onclick = () => {
      const [dx, dy] = b.dataset.move.split(",").map((n) => parseInt(n, 10));
      submit({ kind: "move", dx, dy });
    };
  });
  document.getElementById("btn-cast").onclick = () => submit({ kind: "cast" });
  document.getElementById("btn-wait").onclick = () => submit({ kind: "wait" });
  document.getElementById("btn-attack").onclick = () => {
    if (state.selectedTarget === null) { log("select a target first"); return; }
    submit({ kind: "attack", target: state.selectedTarget });
  };
  document.getElementById("btn-inspect").onclick = () => {
    if (state.selectedTarget === null) { log("select a target first"); return; }
    send("InspectTarget", { target: state.selectedTarget });
  };
}

// ---- replay -------------------------------------------------------------
function initReplay() {
  document.getElementById("btn-replay").onclick = () => {
    if (state.matchId === null) return;
    state.replay = null;
    send("RequestReplay", { match_id: state.matchId });
  };
  document.getElementById("btn-replay-step").onclick = stepReplay;
}

function loadReplay(chunk) {
  if (!state.replay) state.replay = { turns: [], final_hash: chunk.final_hash, cursor: 0, seed: chunk.seed };
  state.replay.turns = state.replay.turns.concat(chunk.turns || []);
  state.replay.final_hash = chunk.final_hash;
  document.getElementById("replay-status").textContent =
    `replay loaded: ${state.replay.turns.length} turns (seed ${chunk.seed})`;
}

function stepReplay() {
  if (!state.replay || state.replay.cursor >= state.replay.turns.length) {
    document.getElementById("replay-status").textContent = "replay complete";
    return;
  }
  const rt = state.replay.turns[state.replay.cursor++];
  // Verify browser replay event order/hash matches what we saw live (Phase G).
  const live = state.liveHashes[rt.turn];
  const ok = live === undefined || live === rt.runtime_hash;
  log(`replay t${rt.turn}: hash ${rt.runtime_hash} ${ok ? "✓ matches live" : "✗ MISMATCH"}`);
  const hd = document.getElementById("hashes");
  hd.innerHTML += `<div class="${ok ? "hash-ok" : "hash-bad"}">t${rt.turn} ${rt.runtime_hash}</div>`;
  document.getElementById("replay-status").textContent =
    `replay turn ${rt.turn} / ${state.replay.turns.length}`;
}

function showHashes() {
  const hd = document.getElementById("hashes");
  hd.innerHTML = `<div>live final-turn hash: ${state.liveHashes[state.turn] || "—"}</div>`;
}

// ---- misc ---------------------------------------------------------------
function log(msg) {
  const el = document.getElementById("log");
  const li = document.createElement("li");
  li.textContent = msg;
  el.appendChild(li);
  el.scrollTop = el.scrollHeight;
}

window.addEventListener("DOMContentLoaded", () => {
  initEditor();
  initActions();
  initReplay();
  connect();
});