import React, { useEffect, useState } from "react";
import Navbar from "../components/Navbar";
import SettingsSidebar, { type SettingsSection } from "../components/SettingsSidebar";
import LlmSettings from "../components/LlmSettings";
import TradingSettings from "../components/TradingSettings";
import StockTable from "../components/StockTable";
import SystemSettings from "../components/SystemSettings";

interface Stock {
  id: string;
  ticker: string;
  notes: string | null;
  lastDecision: string | null;
  lastJobId: string | null;
  createdAt: string;
  updatedAt: string;
}

export default function SettingsPage() {
  const [activeSection, setActiveSection] = useState<SettingsSection>("llm");
  const [settings, setSettings] = useState<Record<string, any>>({});
  const [stocks, setStocks] = useState<Stock[]>([]);
  const [loading, setLoading] = useState(true);
  const [saveError, setSaveError] = useState<string | null>(null);
  const [alpacaMode, setAlpacaMode] = useState<string | null>(null);

  useEffect(() => {
    Promise.all([
      fetch("/api/admin/settings").then((r) => r.json()),
      fetch("/api/stocks").then((r) => r.json()),
      fetch("/api/alpaca/account").then((r) => r.ok ? r.json() : null),
    ]).then(([settingsData, stocksData, accountData]) => {
      const settingsMap: Record<string, any> = {};
      if (Array.isArray(settingsData)) {
        settingsData.forEach((s: { key: string; value: any }) => {
          settingsMap[s.key] = s.value;
        });
      }
      setSettings(settingsMap);
      if (Array.isArray(stocksData)) setStocks(stocksData);
      if (accountData?.trading?.paper !== undefined) {
        setAlpacaMode(accountData.trading.paper ? "paper" : "live");
      }
      setLoading(false);
    }).catch((err) => {
      console.error("Failed to load settings:", err);
      setLoading(false);
    });
  }, []);

  const saveSetting = async (key: string, value: any) => {
    setSaveError(null);
    const prevValue = settings[key];
    setSettings((s) => ({ ...s, [key]: value }));
    try {
      const res = await fetch(`/api/admin/settings/${encodeURIComponent(key)}`, {
        method: "PUT",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({ value }),
      });
      if (!res.ok) {
        throw new Error(`Failed to save ${key}`);
      }
    } catch (err) {
      setSettings((s) => ({ ...s, [key]: prevValue }));
      setSaveError(err instanceof Error ? err.message : "Save failed");
    }
  };

  const saveStockNotes = async (ticker: string, notes: string) => {
    setSaveError(null);
    const prevStocks = [...stocks];
    setStocks((s) => s.map((st) => (st.ticker === ticker ? { ...st, notes } : st)));
    try {
      const fd = new FormData();
      fd.append("ticker", ticker);
      fd.append("notes", notes);
      const res = await fetch("/api/stocks", { method: "POST", body: fd });
      if (!res.ok) {
        throw new Error("Failed to save notes");
      }
    } catch (err) {
      setStocks(prevStocks);
      setSaveError(err instanceof Error ? err.message : "Save failed");
    }
  };

  if (loading) {
    return (
      <div className="min-h-screen bg-gradient-to-br from-gray-50 to-blue-50">
        <Navbar />
        <div className="flex items-center justify-center h-64">
          <div className="text-gray-500">Loading settings...</div>
        </div>
      </div>
    );
  }

  const renderSection = () => {
    switch (activeSection) {
      case "llm":
        return <LlmSettings settings={settings} onSave={saveSetting} saveError={saveError} />;
      case "trading":
        return <TradingSettings settings={settings} onSave={saveSetting} saveError={saveError} />;
      case "stocks":
        return <StockTable stocks={stocks} onNotesSave={saveStockNotes} saveError={saveError} />;
      case "system":
        return <SystemSettings settings={settings} alpacaMode={alpacaMode} onSave={saveSetting} saveError={saveError} />;
      default:
        return null;
    }
  };

  return (
    <div className="min-h-screen bg-gradient-to-br from-gray-50 to-blue-50">
      <Navbar />
      <div className="mx-auto max-w-7xl px-6 sm:px-8 lg:px-8 py-8">
        <div className="bg-white rounded-xl shadow-lg border border-gray-200 overflow-hidden">
          <div className="flex min-h-[600px]">
            <SettingsSidebar activeSection={activeSection} onSectionChange={setActiveSection} />
            <main className="flex-1 p-6 overflow-y-auto">
              {renderSection()}
            </main>
          </div>
        </div>
      </div>
    </div>
  );
}