import { useCallback, useEffect, useMemo, useState } from "react";
import { ShellIcon } from "../../components/ShellIcon";
import "../../styles/pages/more-tools.css";
import "../../styles/pages/script-tokens-v5.css";
import "../../styles/pages/script-tokens.css";
import type {
  WebEnterpriseUsageMember,
  WebEnterpriseUsageRecord,
  WebEnterpriseUsageSummary,
  WebImageWorkbenchTool,
  WebUsageSummary,
  WebUserSession,
  WebViewKey,
} from "../../types";

interface TokenUsagePageProps {
  session: WebUserSession | null;
  usage: WebUsageSummary;
  loadEnterpriseUsage?: () => Promise<WebEnterpriseUsageSummary>;
  loadPersonalUsage?: () => Promise<WebEnterpriseUsageSummary>;
  onOpenMore?: () => void;
  onOpenImageTool?: (tool: WebImageWorkbenchTool) => void;
  onSelectView?: (view: WebViewKey) => void;
}

function formatCredits(cents: number): string {
  const value = Math.max(0, cents) / 100;
  return value >= 1000 ? `${Math.round(value).toLocaleString()} 积分` : `${value.toFixed(2).replace(/\.00$/, "")} 积分`;
}

function formatDateTime(value?: string | null): string {
  if (!value) return "-";
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return value;
  return date.toLocaleString("zh-CN", {
    month: "2-digit",
    day: "2-digit",
    hour: "2-digit",
    minute: "2-digit",
  });
}

function getInitials(value: string): string {
  const normalized = value.trim();
  if (!normalized) return "U";
  return normalized.slice(0, 2).toUpperCase();
}

function getEnterpriseBalanceCents(
  session: WebUserSession | null,
  usage: WebUsageSummary,
  enterpriseUsage: WebEnterpriseUsageSummary | null,
) {
  if (enterpriseUsage) return enterpriseUsage.balanceCents;
  if (typeof usage.enterpriseBalanceCents === "number") return usage.enterpriseBalanceCents;
  return session?.user.enterpriseBalanceCents ?? usage.balanceCents;
}

function memberDisplayName(member: WebEnterpriseUsageMember): string {
  return member.displayName || member.username || String(member.userId);
}

function recordDuration(record: WebEnterpriseUsageRecord): string {
  return record.durationSeconds ? `${record.durationSeconds}s` : record.resolution || "-";
}

const LOW_BALANCE_THRESHOLD_CENTS = 2000;

function formatDayLabel(value: string): string {
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return value;
  return `${date.getMonth() + 1}/${date.getDate()}`;
}

type TrendPoint = { date: string; usedCents: number; taskCount: number };

function UsageTrendChart({ data }: { data: TrendPoint[] }) {
  const W = 680;
  const H = 200;
  const padX = 32;
  const padY = 24;
  const maxCents = Math.max(1, ...data.map((d) => d.usedCents));
  const stepX = data.length > 1 ? (W - padX * 2) / (data.length - 1) : 0;
  const yOf = (cents: number) => H - padY - (cents / maxCents) * (H - padY * 2);
  const xOf = (i: number) => padX + i * stepX;
  const points = data.map((d, i) => ({ x: xOf(i), y: yOf(d.usedCents), ...d }));
  const linePath = points.map((p, i) => `${i === 0 ? "M" : "L"}${p.x.toFixed(1)},${p.y.toFixed(1)}`).join(" ");
  const areaPath = points.length
    ? `${linePath} L${points[points.length - 1].x.toFixed(1)},${H - padY} L${points[0].x.toFixed(1)},${H - padY} Z`
    : "";
  const totalCents = data.reduce((sum, d) => sum + d.usedCents, 0);
  const peak = points.reduce((best, p) => (p.usedCents > best.usedCents ? p : best), points[0] || { usedCents: 0, x: 0, y: 0 });

  return (
    <div className="usage-trend">
      <svg viewBox={`0 0 ${W} ${H}`} className="usage-trend__svg" role="img" aria-label="近 7 天积分消耗趋势">
        <defs>
          <linearGradient id="usageTrendFill" x1="0" y1="0" x2="0" y2="1">
            <stop offset="0%" stopColor="var(--accent)" stopOpacity="0.28" />
            <stop offset="100%" stopColor="var(--accent)" stopOpacity="0" />
          </linearGradient>
        </defs>
        {[0.25, 0.5, 0.75, 1].map((f) => (
          <line key={f} x1={padX} y1={yOf(maxCents * f)} x2={W - padX} y2={yOf(maxCents * f)} className="usage-trend__grid" />
        ))}
        {areaPath ? <path d={areaPath} fill="url(#usageTrendFill)" /> : null}
        {linePath ? <path d={linePath} className="usage-trend__line" /> : null}
        {points.map((p) => (
          <circle key={p.date} cx={p.x} cy={p.y} r={3.5} className="usage-trend__dot">
            <title>{`${formatDayLabel(p.date)} · ${formatCredits(p.usedCents)} · ${p.taskCount} 次`}</title>
          </circle>
        ))}
        {points.map((p, i) => (
          <text key={`lbl-${p.date}`} x={p.x} y={H - 6} className="usage-trend__xlabel" textAnchor={i === 0 ? "start" : i === points.length - 1 ? "end" : "middle"}>
            {formatDayLabel(p.date)}
          </text>
        ))}
      </svg>
      <div className="usage-trend__meta">
        <span>近 7 天共 <b>{formatCredits(totalCents)}</b></span>
        {peak.usedCents > 0 ? <span>峰值 {formatDayLabel(peak.date)} · {formatCredits(peak.usedCents)}</span> : null}
      </div>
    </div>
  );
}

function TokenUsagePage({
  session,
  usage,
  loadEnterpriseUsage,
  loadPersonalUsage,
  onOpenMore,
}: TokenUsagePageProps) {
  const [enterpriseUsage, setEnterpriseUsage] = useState<WebEnterpriseUsageSummary | null>(null);
  const [enterpriseUsageLoading, setEnterpriseUsageLoading] = useState(false);
  const [enterpriseUsageError, setEnterpriseUsageError] = useState<string | null>(null);
  const isEnterpriseAdmin = session?.user.enterpriseRole === "admin";
  const isEnterpriseAccount = Boolean(session?.user.enterpriseId || session?.user.accountType === "enterprise");

  const refreshEnterpriseUsage = useCallback(async () => {
    if (!session) return;
    const loader = isEnterpriseAdmin ? loadEnterpriseUsage : loadPersonalUsage;
    if (!loader) {
      setEnterpriseUsage(null);
      return;
    }
    setEnterpriseUsageLoading(true);
    setEnterpriseUsageError(null);
    try {
      setEnterpriseUsage(await loader());
    } catch (error) {
      setEnterpriseUsage(null);
      setEnterpriseUsageError(error instanceof Error ? error.message : "加载失败");
    } finally {
      setEnterpriseUsageLoading(false);
    }
  }, [session, isEnterpriseAdmin, loadEnterpriseUsage, loadPersonalUsage]);

  useEffect(() => {
    void refreshEnterpriseUsage();
  }, [refreshEnterpriseUsage]);

  const enterpriseBalanceCents = getEnterpriseBalanceCents(session, usage, enterpriseUsage);
  const totalCalls = enterpriseUsage
    ? enterpriseUsage.members.reduce((sum, member) => sum + member.taskCount, 0)
    : usage.imageUsed + usage.videoUsed + usage.textUsed;
  const totalUsedCents = enterpriseUsage?.totalUsedCents ?? 0;
  const modelBreakdown = enterpriseUsage?.modelBreakdown ?? [];
  const dailyTrend = enterpriseUsage?.dailyTrend ?? [];
  const availableBalanceCents = isEnterpriseAccount ? enterpriseBalanceCents : usage.balanceCents;
  const isLowBalance = !usage.betaUnlimited && availableBalanceCents < LOW_BALANCE_THRESHOLD_CENTS;
  const maxModelCents = Math.max(1, ...modelBreakdown.map((m) => m.usedCents));
  const records = enterpriseUsage?.records ?? [];
  const [recordPage, setRecordPage] = useState(0);
  const pageSize = 10;
  const totalPages = Math.max(1, Math.ceil(records.length / pageSize));
  const pagedRecords = records.slice(recordPage * pageSize, (recordPage + 1) * pageSize);
  const members = useMemo<WebEnterpriseUsageMember[]>(() => {
    if (enterpriseUsage && enterpriseUsage.members.length) return enterpriseUsage.members;
    if (!session) return [];
    return [
      {
        userId: session.user.id,
        username: session.user.username,
        displayName: session.user.displayName,
        role: session.user.enterpriseRole || session.user.role || "personal",
        usedCents: 0,
        taskCount: totalCalls,
        lastUsedAt: null,
      },
    ];
  }, [enterpriseUsage, session, totalCalls]);

  const metricCards = [
    {
      key: "balance",
      label: "可用余额",
      value: usage.betaUnlimited ? "不限量" : formatCredits(availableBalanceCents),
      hint: isLowBalance ? "余额偏低，建议充值" : isEnterpriseAccount ? "企业共享额度" : "个人账户额度",
      tone: isLowBalance ? "warn" : "accent",
    },
    {
      key: "used",
      label: "已用积分",
      value: formatCredits(totalUsedCents),
      hint: enterpriseUsage ? `${enterpriseUsage.enterpriseName || "企业"}累计` : "累计消耗",
      tone: "neutral",
    },
    {
      key: "calls",
      label: "调用次数",
      value: `${totalCalls}`,
      hint: `${modelBreakdown.length || 0} 个模型`,
      tone: "neutral",
    },
  ];

  const systemStatus = [
    { label: "账户类型", value: isEnterpriseAccount ? "企业账户" : "个人账户", tone: "good" },
    { label: "企业空间", value: enterpriseUsage?.enterpriseName || session?.user.enterpriseName || "-" },
  ];
  const pageStatusClass = enterpriseUsageLoading
    ? "is-syncing"
    : enterpriseUsageError
      ? "has-sync-error"
      : isLowBalance
        ? "has-low-balance"
        : "is-healthy";

  return (
    <section className={`script-token-page token-usage-page management-center-page ${pageStatusClass}`} aria-label="管理中心">
      <main className="management-center-shell">
        <header className="management-center-toolbar" aria-label="管理中心操作">
          <div className="management-center-toolbar__title">
            <button type="button" className="management-center-toolbar__back" aria-label="返回工具盒" onClick={onOpenMore}>
              <ShellIcon name="arrow-left" />
            </button>
            <span>
              <strong>管理中心</strong>
              <small>用量、成员与模型调用监控</small>
            </span>
          </div>
          <span className={`management-center-status-pill ${enterpriseUsageError ? "is-error" : enterpriseUsageLoading ? "is-loading" : "is-online"}`}>
            {enterpriseUsageLoading ? "正在同步企业用量" : enterpriseUsageError || "服务器已连接"}
          </span>
          <button type="button" onClick={refreshEnterpriseUsage} disabled={enterpriseUsageLoading}>
            <ShellIcon name="reload" />
            刷新数据
          </button>
          <button type="button" className="is-muted-action">
            <ShellIcon name="user" />
            成员管理
          </button>
        </header>

        {isLowBalance ? (
          <div className="management-balance-alert" role="alert">
            <ShellIcon name="warning" />
            <span>当前余额 {formatCredits(availableBalanceCents)}，可能不足以完成下一次生成，请及时充值。</span>
          </div>
        ) : null}

        <section className="management-metric-cards" aria-label="关键指标">
          {metricCards.map((card) => (
            <article key={card.key} className={`management-metric-card is-${card.tone}`}>
              <span className="management-metric-card__label">{card.label}</span>
              <strong className="management-metric-card__value">{card.value}</strong>
              <span className="management-metric-card__hint">{card.hint}</span>
            </article>
          ))}
        </section>

        <section className="management-center-overview" aria-label="系统概览">
          <article className="management-card management-card--chart">
            <div className="management-card__head">
              <h2>
                <ShellIcon name="bar-chart" />
                模型消耗分布
              </h2>
              <span>{enterpriseUsageLoading ? "SYNC" : modelBreakdown.length ? `${modelBreakdown.length} 个模型` : "LIVE"}</span>
            </div>
            {modelBreakdown.length ? (
              <div className="management-model-list">
                {modelBreakdown.map((item) => (
                  <div className="management-model-bar" key={item.model}>
                    <div className="management-model-bar__top">
                      <strong title={item.model}>{item.model}</strong>
                      <em>{formatCredits(item.usedCents)}</em>
                    </div>
                    <div className="management-model-bar__track">
                      <span style={{ width: `${Math.max(4, Math.round((item.usedCents / maxModelCents) * 100))}%` }} />
                    </div>
                    <span className="management-model-bar__sub">{item.taskCount} 次调用 · {Math.round((item.usedCents / Math.max(1, totalUsedCents)) * 100)}%</span>
                  </div>
                ))}
              </div>
            ) : (
              <div className="management-empty-chart">
                <ShellIcon name="bar-chart" />
                <span>暂无模型用量数据</span>
              </div>
            )}
          </article>

          <article className="management-card management-status-card">
            <div className="management-card__head">
              <h2>
                <ShellIcon name="line-chart" />
                系统状态
              </h2>
            </div>
            <dl>
              {systemStatus.map((item) => (
                <div key={item.label}>
                  <dt>{item.label}</dt>
                  <dd className={item.tone === "good" ? "is-good" : undefined}>
                    {item.tone === "good" ? <i /> : null}
                    {item.value}
                  </dd>
                </div>
              ))}
            </dl>
            <div className="management-status-trend">
              <span className="management-status-trend__title">近 7 天趋势</span>
              {dailyTrend.some((d) => d.usedCents > 0) ? (
                <UsageTrendChart data={dailyTrend} />
              ) : (
                <span className="management-status-trend__empty">暂无数据</span>
              )}
            </div>
          </article>
        </section>

        <section className="management-card management-members">
          <div className="management-card__head">
            <h2>
              <ShellIcon name="team" />
              团队成员 ({members.length})
            </h2>
            <button type="button">{isEnterpriseAdmin ? "企业管理员" : "当前账号"}</button>
          </div>
          <div className="management-member-list">
            {members.map((member) => (
              <article key={String(member.userId)} className="management-member-row">
                <span className="management-member-avatar">{getInitials(memberDisplayName(member))}</span>
                <div>
                  <strong>{memberDisplayName(member)}</strong>
                  <em>uid: {member.userId}</em>
                </div>
                <span className="management-member-role">{member.role === "admin" ? "管理员" : member.role === "employee" ? "员工" : member.role}</span>
                <span>{formatCredits(member.usedCents)}</span>
                <span className="management-member-meter">
                  <b>{member.taskCount} 调用</b>
                  <b>{formatDateTime(member.lastUsedAt)}</b>
                </span>
                <ShellIcon name="check-circle" />
              </article>
            ))}
          </div>
        </section>

        <section className="management-card management-records">
          <div className="management-card__head">
            <h2>
              <ShellIcon name="bar-chart" />
              调用记录
            </h2>
            <span>{records.length} 条记录</span>
          </div>
          <div className="management-record-table" role="table" aria-label="调用记录">
            <div role="row" className="management-record-table__head">
              <span role="columnheader">时间</span>
              <span role="columnheader">用户</span>
              <span role="columnheader">模型</span>
              <span role="columnheader">提示词</span>
              <span role="columnheader">状态</span>
              <span role="columnheader">耗时</span>
              <span role="columnheader">积分</span>
            </div>
            {pagedRecords.length ? (
              pagedRecords.map((record) => (
                <div role="row" className="management-record-table__row" key={record.id}>
                  <span>{formatDateTime(record.createdAt)}</span>
                  <span>{record.username}</span>
                  <span>{record.model}</span>
                  <span title={record.prompt || ""}>{record.prompt || "-"}</span>
                  <span className={record.status === "completed" ? "is-good" : record.status === "failed" ? "is-error" : undefined}>{record.status === "completed" ? "成功" : record.status === "failed" ? "失败" : record.status}</span>
                  <span>{recordDuration(record)}</span>
                  <span>{record.amountCents > 0 ? formatCredits(record.amountCents) : "-"}</span>
                </div>
              ))
            ) : (
              <div className="management-record-empty" role="row">
                暂无调用记录
              </div>
            )}
          </div>
          {records.length > pageSize && (
            <div className="management-record-pagination">
              <button type="button" disabled={recordPage === 0} onClick={() => setRecordPage((p) => p - 1)}>
                <ShellIcon name="chevron-left" />
              </button>
              <span>{recordPage + 1} / {totalPages}</span>
              <button type="button" disabled={recordPage >= totalPages - 1} onClick={() => setRecordPage((p) => p + 1)}>
                <ShellIcon name="chevron-right" />
              </button>
            </div>
          )}
        </section>
      </main>
    </section>
  );
}

export default TokenUsagePage;
