/**
 * 实盘下单：币种 + 止盈止损填完后拉 /api/order_defaults 快照，在开仓按钮前显示预估盈亏比。
 * 仅价格 / 百分比模式；固定盈亏比模式沿用「预估止盈」，不显示预估盈亏比。
 */
(function (global) {
  "use strict";

  let debounceMs = 400;
  let minRr = 1.5;
  let debounceTimer = null;
  let fetchSeq = 0;

  function $(id) {
    return document.getElementById(id);
  }

  function num(v) {
    const n = Number(v);
    return Number.isFinite(n) ? n : null;
  }

  function formatRr(rr) {
    if (rr === null || typeof rr === "undefined") return "—";
    const n = Number(rr);
    if (!Number.isFinite(n)) return "—";
    const body = Number.isInteger(n) ? String(n) : String(parseFloat(n.toFixed(2)));
    return body + ":1";
  }

  function calcRr(direction, entry, sl, tp) {
    const e = num(entry);
    const s = num(sl);
    const t = num(tp);
    if (e === null || s === null || t === null) return null;
    if (direction === "short") {
      if (s <= e || t >= e) return null;
      return (e - t) / (s - e);
    }
    if (s >= e || t <= e) return null;
    return (t - e) / (e - s);
  }

  function calcRrFromPct(slPct, tpPct) {
    const sl = num(slPct);
    const tp = num(tpPct);
    if (sl === null || tp === null || sl <= 0 || tp <= 0) return null;
    return tp / sl;
  }

  function currentMode() {
    return ($("sltp-mode") && $("sltp-mode").value) || "fixed_rr";
  }

  function currentDirection() {
    return ($("order-direction") && $("order-direction").value) || "long";
  }

  function currentSymbol() {
    return (($("order-symbol") && $("order-symbol").value) || "").trim();
  }

  function inputsComplete(m) {
    const dir = currentDirection();
    if (!currentSymbol() || !dir) return false;
    if (m === "pct") {
      const sl = num($("order-sl-pct") && $("order-sl-pct").value);
      const tp = num($("order-tp-pct") && $("order-tp-pct").value);
      return sl !== null && tp !== null && sl > 0 && tp > 0;
    }
    const sl = num($("order-sl") && $("order-sl").value);
    const tp = num($("order-tp") && $("order-tp").value);
    return sl !== null && tp !== null && sl > 0 && tp > 0;
  }

  function hidePreview() {
    const el = $("order-rr-preview");
    if (el) el.style.display = "none";
  }

  function paint(rr, state) {
    const el = $("order-rr-preview");
    if (!el) return;
    const m = currentMode();
    if (m === "fixed_rr" || (m !== "price" && m !== "pct")) {
      el.style.display = "none";
      return;
    }
    el.style.display = "";
    if (state === "empty") {
      el.textContent = "预估盈亏比：—";
      el.style.color = "#8fc8ff";
      return;
    }
    if (state === "loading") {
      el.textContent = "预估盈亏比：计算中…";
      el.style.color = "#8fc8ff";
      return;
    }
    if (state === "fetch_fail") {
      el.textContent = "预估盈亏比：取价失败";
      el.style.color = "#ff8f8f";
      return;
    }
    if (rr === null) {
      el.textContent = "预估盈亏比：无效";
      el.style.color = "#ff8f8f";
      return;
    }
    el.textContent = "预估盈亏比：" + formatRr(rr);
    el.style.color = rr >= minRr ? "#4cd97f" : "#ff8f8f";
  }

  function refreshNow() {
    const m = currentMode();
    if (m === "fixed_rr") {
      hidePreview();
      return;
    }
    if (!inputsComplete(m)) {
      paint(null, "empty");
      return;
    }

    const sym = currentSymbol();
    const dir = currentDirection();
    const seq = ++fetchSeq;
    paint(null, "loading");

    fetch(
      "/api/order_defaults?symbol=" +
        encodeURIComponent(sym) +
        "&direction=" +
        encodeURIComponent(dir)
    )
      .then(function (r) {
        return r.json();
      })
      .then(function (data) {
        if (seq !== fetchSeq) return;
        if (!data.ok) {
          paint(null, "fetch_fail");
          return;
        }
        if (m === "pct") {
          const rr = calcRrFromPct(
            $("order-sl-pct") && $("order-sl-pct").value,
            $("order-tp-pct") && $("order-tp-pct").value
          );
          paint(rr, rr === null ? "invalid" : "ok");
          return;
        }
        const entry = num(data.last_price != null ? data.last_price : data.price);
        if (entry === null) {
          paint(null, "fetch_fail");
          return;
        }
        const sl = num($("order-sl") && $("order-sl").value);
        const tp = num($("order-tp") && $("order-tp").value);
        const rr = calcRr(dir, entry, sl, tp);
        paint(rr, rr === null ? "invalid" : "ok");
      })
      .catch(function () {
        if (seq !== fetchSeq) return;
        paint(null, "fetch_fail");
      });
  }

  function schedule() {
    clearTimeout(debounceTimer);
    debounceTimer = setTimeout(refreshNow, debounceMs);
  }

  function wire(opts) {
    opts = opts || {};
    if (opts.minRr != null && Number.isFinite(Number(opts.minRr))) {
      minRr = Number(opts.minRr);
    }
    if (opts.debounceMs != null && Number.isFinite(Number(opts.debounceMs))) {
      debounceMs = Number(opts.debounceMs);
    }
    [
      "order-symbol",
      "order-direction",
      "sltp-mode",
      "order-sl",
      "order-tp",
      "order-sl-pct",
      "order-tp-pct",
      "order-fixed-rr",
    ].forEach(function (id) {
      const el = $(id);
      if (!el || el._rrPreviewBound) return;
      el._rrPreviewBound = true;
      el.addEventListener("input", schedule);
      el.addEventListener("change", schedule);
    });
    schedule();
  }

  global.ManualOrderRrPreview = {
    wire: wire,
    schedule: schedule,
    refresh: refreshNow,
    calcRr: calcRr,
    calcRrFromPct: calcRrFromPct,
    formatRr: formatRr,
  };
})(typeof window !== "undefined" ? window : globalThis);