import { runtimeApi, segmentControl } from "./api.js";

const STATE_LABEL = {
  idle: "空闲",
  checking: "校验",
  executing: "执行",
  confirming: "等待确认",
  resetting: "复位",
  completed: "完成",
  blocked: "阻塞",
  faulted: "故障",
  manual_ack_required: "待人工确认",
};

const STATE_CLASS = {
  idle: "state-idle",
  checking: "state-active",
  executing: "state-active",
  confirming: "state-active",
  resetting: "state-active",
  completed: "state-active",
  blocked: "state-warn",
  faulted: "state-error",
  manual_ack_required: "state-warn",
};

const segments = new Map();

function escapeHtml(text) {
  if (text === null || text === undefined) return "";
  return String(text)
    .replaceAll("&", "&")
    .replaceAll("<", "&lt;")
    .replaceAll(">", "&gt;");
}

function renderState(runtime) {
  const state = runtime?.state || "idle";
  const label = STATE_LABEL[state] || state;
  const cls = STATE_CLASS[state] || "state-idle";
  return `<span class="state-badge ${cls}">${escapeHtml(label)}</span>`;
}

function renderActions(seg) {
  const runtime = seg.runtime || {};
  const autoOn = runtime.auto_enabled === true;
  const state = runtime.state || "idle";
  const canAck = state === "faulted" || state === "manual_ack_required";
  const canReset = canAck || state === "blocked";
  return `
    <div class="card-actions">
      <button data-action="start-auto" data-id="${seg.segment.id}" ${autoOn ? "disabled" : ""}>启动</button>
      <button data-action="stop-auto" data-id="${seg.segment.id}" ${autoOn ? "" : "disabled"}>停止</button>
      <button data-action="ack-fault" data-id="${seg.segment.id}" ${canAck ? "" : "disabled"}>故障确认</button>
      <button data-action="reset" data-id="${seg.segment.id}" ${canReset ? "" : "disabled"}>复位</button>
    </div>
  `;
}

function renderCard(seg) {
  const segment = seg.segment;
  const runtime = seg.runtime || {};
  const note = runtime.fault_message || runtime.blocked_reason || "";
  const lineTag = segment.line_code ? `<span class="badge">${escapeHtml(segment.line_code)}</span>` : "";
  const modeTag = `<span class="badge">${escapeHtml(segment.mode)}</span>`;
  const autoTag = runtime.auto_enabled
    ? `<span class="badge badge-accent">AUTO</span>`
    : "";
  const stepText = runtime.current_step_no === null || runtime.current_step_no === undefined
    ? "—"
    : `Step ${runtime.current_step_no}`;
  return `
    <article class="ops-card" data-segment-id="${segment.id}">
      <header class="card-head">
        <div class="card-title">
          <strong>${escapeHtml(segment.code)}</strong>
          <span class="muted">${escapeHtml(segment.name)}</span>
        </div>
        <div class="card-tags">${lineTag}${modeTag}${autoTag}${renderState(runtime)}</div>
      </header>
      <div class="card-body">
        <div class="card-row"><span class="muted">当前步骤</span><span>${escapeHtml(stepText)}</span></div>
        ${note ? `<div class="card-note">${escapeHtml(note)}</div>` : ""}
      </div>
      ${renderActions(seg)}
    </article>
  `;
}

function renderAll() {
  const root = document.getElementById("segmentList");
  if (!root) return;
  const items = Array.from(segments.values());
  items.sort((a, b) => a.segment.code.localeCompare(b.segment.code));
  if (items.length === 0) {
    root.innerHTML = `<div class="muted card-empty">尚无段配置；执行种子或通过配置页新增段。</div>`;
    return;
  }
  root.innerHTML = items.map(renderCard).join("");
}

function setBanner(message, level = "info") {
  const root = document.getElementById("segmentList");
  if (!root) return;
  const existing = root.querySelector(".ops-banner");
  if (existing) existing.remove();
  const div = document.createElement("div");
  div.className = `ops-banner banner-${level}`;
  div.textContent = message;
  root.prepend(div);
  window.setTimeout(() => div.remove(), 4000);
}

async function callAndRefresh(label, fn) {
  try {
    await fn();
    setBanner(`${label} 成功`, "info");
  } catch (err) {
    setBanner(err.message || String(err), "error");
  }
}

function handleAction(event) {
  const button = event.target.closest("button[data-action]");
  if (!button) return;
  const action = button.dataset.action;
  const id = button.dataset.id;
  switch (action) {
    case "start-auto":
      return callAndRefresh("启动自动控制", () => segmentControl.startAuto(id));
    case "stop-auto":
      return callAndRefresh("停止自动控制", () => segmentControl.stopAuto(id));
    case "ack-fault":
      return callAndRefresh("故障确认", () => segmentControl.ackFault(id));
    case "reset":
      return callAndRefresh("复位", () => segmentControl.reset(id));
    default:
      return undefined;
  }
}

export async function loadSegments() {
  const data = await runtimeApi.fetchOverview();
  segments.clear();
  (data?.segments || []).forEach((entry) => {
    segments.set(entry.segment.id, entry);
  });
  renderAll();
}

/// Apply a SegmentRuntime payload pushed via WebSocket app_event.
export function applyRuntimeUpdate(runtime) {
  if (!runtime?.segment_id) return;
  const entry = segments.get(runtime.segment_id);
  if (!entry) {
    // Unknown segment — refresh from overview so we pick it up.
    void loadSegments();
    return;
  }
  entry.runtime = runtime;
  renderAll();
}

export function bindSegmentEvents() {
  const root = document.getElementById("segmentList");
  if (root) root.addEventListener("click", handleAction);
  const refreshBtn = document.getElementById("refreshSegmentsBtn");
  if (refreshBtn) {
    refreshBtn.addEventListener("click", () => callAndRefresh("刷新", loadSegments));
  }
  const batchStart = document.getElementById("batchStartAutoBtn");
  if (batchStart) {
    batchStart.addEventListener("click", async () => {
      await callAndRefresh("批量启动", () => segmentControl.batchStart());
      await loadSegments();
    });
  }
  const batchStop = document.getElementById("batchStopAutoBtn");
  if (batchStop) {
    batchStop.addEventListener("click", async () => {
      await callAndRefresh("批量停止", () => segmentControl.batchStop());
      await loadSegments();
    });
  }
}