"use client";

import { FormEvent, useState } from "react";
import { Building2, Globe2, KeyRound, Save, ShieldCheck, UserPlus } from "lucide-react";
import { useRouter } from "next/navigation";

import { Badge } from "@/components/ui/badge";
import { Button, LinkButton } from "@/components/ui/button";
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
import { Checkbox } from "@/components/ui/checkbox";
import { Input } from "@/components/ui/input";
import type { ApiResult } from "@/modules/core/server/api";
import type { SystemSettings } from "@/modules/core/types";

type GlobalSettingsClientProps = {
  organizationSettingsHref: string;
  settings: SystemSettings;
};

type SettingsTab = "registration" | "invitation" | "oidc";

const tabs: Array<{ label: string; value: SettingsTab }> = [
  { label: "注册入口", value: "registration" },
  { label: "邀请注册", value: "invitation" },
  { label: "OIDC 默认配置", value: "oidc" },
];

export function GlobalSettingsClient({
  organizationSettingsHref,
  settings,
}: GlobalSettingsClientProps): React.ReactElement {
  const router = useRouter();
  const [activeTab, setActiveTab] = useState<SettingsTab>("registration");
  const [registrationEnabled, setRegistrationEnabled] = useState(settings.registrationEnabled);
  const [oidcEnabled, setOidcEnabled] = useState(settings.oidcEnabled);
  const [oidcAutoProvision, setOidcAutoProvision] = useState(settings.oidcAutoProvision);
  const [message, setMessage] = useState("");
  const [isPending, setIsPending] = useState(false);

  async function handleSubmit(event: FormEvent<HTMLFormElement>): Promise<void> {
    event.preventDefault();
    setMessage("");
    setIsPending(true);

    const formData = new FormData(event.currentTarget);
    const response = await fetch("/api/settings/global", {
      method: "PATCH",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({
        registrationEnabled,
        oidcEnabled,
        oidcIssuerUrl: String(formData.get("oidcIssuerUrl") ?? ""),
        oidcClientId: String(formData.get("oidcClientId") ?? ""),
        oidcClientSecret: String(formData.get("oidcClientSecret") ?? ""),
        oidcScopes: String(formData.get("oidcScopes") ?? ""),
        oidcRedirectUri: String(formData.get("oidcRedirectUri") ?? ""),
        oidcAvatarClaim: String(formData.get("oidcAvatarClaim") ?? ""),
        oidcAutoProvision,
      }),
    });
    const result = (await response.json()) as ApiResult<{ settings: SystemSettings }>;
    setIsPending(false);

    if (!result.success) {
      setMessage(result.reason);
      return;
    }

    setMessage(result.reason);
    router.refresh();
  }

  return (
    <form className="grid gap-4" onSubmit={handleSubmit}>
      <div className="flex flex-wrap gap-2" role="tablist" aria-label="全局配置">
        {tabs.map((tab) => (
          <Button
            aria-selected={activeTab === tab.value}
            key={tab.value}
            onClick={() => setActiveTab(tab.value)}
            role="tab"
            type="button"
            variant={activeTab === tab.value ? "default" : "outline"}
          >
            {tab.label}
          </Button>
        ))}
      </div>

      <Card>
        <div hidden={activeTab !== "registration"} role="tabpanel">
          <CardHeader>
            <div className="flex items-center gap-2">
              <Globe2 className="size-5 text-primary" aria-hidden="true" />
              <CardTitle>注册与入口</CardTitle>
            </div>
            <CardDescription>控制全站公开注册能力和 OIDC 登录入口总开关。</CardDescription>
          </CardHeader>
          <CardContent className="grid gap-4">
            <div className="rounded-md border p-3 text-sm">
              <Checkbox
                checked={registrationEnabled}
                label={
                  <span className="min-w-0">
                    <span className="block font-medium">开放公开注册</span>
                    <span className="block text-xs text-muted-foreground">关闭后普通注册不可用；邀请链接仍可使用。</span>
                  </span>
                }
                name="registrationEnabled"
                onCheckedChange={setRegistrationEnabled}
              />
            </div>

            <div className="rounded-md border p-3 text-sm">
              <Checkbox
                checked={oidcEnabled}
                label={
                  <span className="min-w-0">
                    <span className="block font-medium">启用 OIDC 登录</span>
                    <span className="block text-xs text-muted-foreground">作为平台级总开关，机构级 OIDC 配置仍可单独管理。</span>
                  </span>
                }
                name="oidcEnabled"
                onCheckedChange={setOidcEnabled}
              />
            </div>

            <div className="rounded-md border p-3 text-sm">
              <Checkbox
                checked={oidcAutoProvision}
                label={
                  <span className="min-w-0">
                    <span className="block font-medium">OIDC 自动开户</span>
                    <span className="block text-xs text-muted-foreground">首次 OIDC 登录时按声明信息创建账号，默认进入等待分配。</span>
                  </span>
                }
                name="oidcAutoProvision"
                onCheckedChange={setOidcAutoProvision}
              />
            </div>
          </CardContent>
        </div>
        <div hidden={activeTab !== "invitation"} role="tabpanel">
          <CardHeader>
            <div className="flex items-center gap-2">
              <KeyRound className="size-5 text-primary" aria-hidden="true" />
              <CardTitle>邀请码与加入方式</CardTitle>
            </div>
            <CardDescription>集中说明公开注册、机构邀请和加入申请的关系，邀请码在机构管理中生成。</CardDescription>
          </CardHeader>
          <CardContent className="grid gap-4">
            <div className="grid gap-3 lg:grid-cols-3">
              <section className="rounded-md border p-3">
                <div className="flex items-center gap-2">
                  <Globe2 className="size-4 text-primary" aria-hidden="true" />
                  <h3 className="text-sm font-semibold">公开注册</h3>
                </div>
                <p className="mt-2 text-sm text-muted-foreground">
                  {registrationEnabled
                    ? "访客可以从注册页创建账号，并选择申请加入开放注册的机构。"
                    : "普通注册入口关闭；用户需要通过邀请链接或管理员创建账号。"}
                </p>
              </section>
              <section className="rounded-md border p-3">
                <div className="flex items-center gap-2">
                  <UserPlus className="size-4 text-primary" aria-hidden="true" />
                  <h3 className="text-sm font-semibold">机构邀请</h3>
                </div>
                <p className="mt-2 text-sm text-muted-foreground">
                  邀请链接格式为 `/register?invite=...`，可限定邮箱、角色、有效期和使用次数，适合定向开通账号。
                </p>
              </section>
              <section className="rounded-md border p-3">
                <div className="flex items-center gap-2">
                  <Building2 className="size-4 text-primary" aria-hidden="true" />
                  <h3 className="text-sm font-semibold">加入审批</h3>
                </div>
                <p className="mt-2 text-sm text-muted-foreground">
                  未持邀请码的用户申请加入机构后，需要管理员在用户管理中审批并分配角色。
                </p>
              </section>
            </div>
            <div className="flex flex-col gap-3 rounded-md border bg-secondary/25 p-3 sm:flex-row sm:items-center sm:justify-between">
              <div className="min-w-0 text-sm">
                <p className="font-medium">前往机构管理生成邀请码</p>
                <p className="mt-1 text-muted-foreground">选择机构行内的“邀请”，生成有有效期和使用次数限制的注册链接。</p>
              </div>
              <LinkButton href={organizationSettingsHref} variant="outline">
                <UserPlus className="size-4" aria-hidden="true" />
                管理机构邀请
              </LinkButton>
            </div>
          </CardContent>
        </div>
        <div hidden={activeTab !== "oidc"} role="tabpanel">
          <CardHeader>
            <div className="flex items-center gap-2">
              <ShieldCheck className="size-5 text-primary" aria-hidden="true" />
              <CardTitle>OIDC 默认配置</CardTitle>
            </div>
            <CardDescription>保存标准 OIDC issuer、client、scope 和头像 claim。</CardDescription>
          </CardHeader>
          <CardContent className="grid gap-4">
            <div className="grid gap-3 md:grid-cols-2">
              <Input
                defaultValue={settings.oidcIssuerUrl}
                label="Issuer URL"
                name="oidcIssuerUrl"
                placeholder="https://idp.example.com"
              />
              <Input defaultValue={settings.oidcClientId} label="Client ID" name="oidcClientId" />
            </div>

            <Input
              label="Client Secret"
              name="oidcClientSecret"
              placeholder={settings.oidcHasClientSecret ? "已配置，留空则不修改" : "未配置"}
              type="password"
            />

            <div className="grid gap-3 md:grid-cols-2">
              <Input defaultValue={settings.oidcScopes} label="Scopes" name="oidcScopes" placeholder="openid profile email" />
              <Input
                defaultValue={settings.oidcRedirectUri}
                label="Redirect URI"
                name="oidcRedirectUri"
                placeholder="/api/auth/oidc/callback"
              />
            </div>

            <Input defaultValue={settings.oidcAvatarClaim} label="Avatar Claim" name="oidcAvatarClaim" placeholder="picture" />
          </CardContent>
        </div>
      </Card>

      {message ? (
        <p className="rounded-md bg-secondary px-3 py-2 text-sm text-secondary-foreground" role="status">
          {message}
        </p>
      ) : null}

      <div className="flex items-center justify-between gap-3">
        <Badge variant={oidcEnabled ? "success" : "secondary"}>
          {oidcEnabled ? "OIDC 已启用" : "OIDC 未启用"}
        </Badge>
        <Button disabled={isPending} type="submit">
          <Save className="size-4" aria-hidden="true" />
          保存配置
        </Button>
      </div>
    </form>
  );
}