"use client";

import { useState } from "react";

import { api } from "@/lib/api/client";
import { useToast } from "@/components/Toast";
import { KNOWN_PROVIDERS, TIER_LABELS } from "@/lib/settings/providers";
import type {
  CapabilitiesView,
  ProvidersResponse,
  TierRoutingView,
} from "@/lib/api/types";

interface ProvidersSettingsProps {
  initial: ProvidersResponse;
}

interface TestResult {
  ok: boolean;
  capabilities: CapabilitiesView;
}

// 设置页主体（UX §6.10）：档位路由（只读展示）+ 凭据行（脱敏 / 添加更新 / 测试连接）。
export function ProvidersSettings({ initial }: ProvidersSettingsProps) {
  const toast = useToast();
  const [providers, setProviders] = useState(initial.providers ?? []);
  const tierRouting: TierRoutingView[] = initial.tier_routing ?? [];
  const [drafts, setDrafts] = useState<Record<string, string>>({});
  const [savingId, setSavingId] = useState<string | null>(null);
  const [testingId, setTestingId] = useState<string | null>(null);
  const [results, setResults] = useState<Record<string, TestResult>>({});

  const maskedFor = (id: string): string | null =>
    providers.find((p) => p.provider === id)?.masked_key ?? null;

  const saveCredential = async (providerId: string): Promise<void> => {
    const apiKey = (drafts[providerId] ?? "").trim();
    if (!apiKey) {
      toast("请先输入 API Key", "error");
      return;
    }
    setSavingId(providerId);
    const { data, error } = await api.PUT("/settings/providers", {
      body: { credentials: [{ provider: providerId, api_key: apiKey }] },
    });
    setSavingId(null);
    if (error || !data) {
      toast("保存凭据失败，请重试", "error");
      return;
    }
    setProviders(data.providers ?? []);
    setDrafts((prev) => ({ ...prev, [providerId]: "" }));
    toast("凭据已保存", "success");
  };

  const testConnection = async (providerId: string): Promise<void> => {
    setTestingId(providerId);
    const { data, error } = await api.POST("/settings/providers/test", {
      body: { provider: providerId },
    });
    setTestingId(null);
    if (error || !data) {
      toast("测试连接失败", "error");
      return;
    }
    setResults((prev) => ({
      ...prev,
      [providerId]: { ok: data.ok, capabilities: data.capabilities },
    }));
    toast(data.ok ? "连接成功" : "连接未通过", data.ok ? "success" : "error");
  };

  return (
    <div>
      <section className="mb-10">
        <h2 className="mb-3 font-serif text-xl text-ink">能力档位路由</h2>
        {tierRouting.length === 0 ? (
          <p className="rounded border border-dashed border-line bg-panel p-4 text-sm text-ink-soft">
            尚未配置档位路由。连接提供商后将使用默认路由。
          </p>
        ) : (
          <ul className="divide-y divide-line rounded border border-line bg-panel">
            {tierRouting.map((t) => (
              <li
                key={t.tier}
                className="flex items-center gap-4 px-4 py-3 text-sm"
              >
                <span className="w-20 text-ink">
                  {TIER_LABELS[t.tier] ?? t.tier}
                </span>
                <span className="font-mono text-ink-soft">
                  {t.provider} · {t.model}
                </span>
                {t.fallback && t.fallback.length > 0 ? (
                  <span className="ml-auto font-mono text-xs text-ink-soft">
                    回退 {t.fallback.join(", ")}
                  </span>
                ) : null}
              </li>
            ))}
          </ul>
        )}
      </section>

      <section>
        <h2 className="mb-3 font-serif text-xl text-ink">提供商凭据</h2>
        {providers.length === 0 ? (
          <p className="mb-4 rounded border border-dashed border-line bg-panel p-4 text-sm text-ink-soft">
            至少连接一个提供商即可开始写作（求质量选 Anthropic / 求性价比选
            DeepSeek）。
          </p>
        ) : null}
        <ul className="divide-y divide-line rounded border border-line bg-panel">
          {KNOWN_PROVIDERS.map((prov) => {
            const masked = maskedFor(prov.id);
            const result = results[prov.id];
            return (
              <li key={prov.id} className="px-4 py-4">
                <div className="flex flex-wrap items-center gap-3">
                  <span
                    className={`h-2 w-2 rounded-full ${masked ? "bg-pass" : "bg-line"}`}
                    aria-hidden="true"
                  />
                  <span className="w-28 text-sm text-ink">{prov.label}</span>
                  {masked ? (
                    <span className="font-mono text-xs text-ink-soft">
                      {masked}
                    </span>
                  ) : null}
                  <label className="sr-only" htmlFor={`key-${prov.id}`}>
                    {prov.label} API Key
                  </label>
                  <input
                    id={`key-${prov.id}`}
                    type="password"
                    autoComplete="off"
                    value={drafts[prov.id] ?? ""}
                    onChange={(e) =>
                      setDrafts((prev) => ({
                        ...prev,
                        [prov.id]: e.target.value,
                      }))
                    }
                    placeholder={masked ? "输入新 Key 以更新" : "输入 API Key"}
                    className="min-w-[12rem] flex-1 rounded border border-line bg-bg px-3 py-1.5 text-sm text-ink focus:border-cinnabar focus:outline-none"
                  />
                  <button
                    type="button"
                    onClick={() => saveCredential(prov.id)}
                    disabled={savingId === prov.id}
                    className="rounded bg-cinnabar px-3 py-1.5 text-sm text-panel disabled:opacity-40"
                  >
                    {savingId === prov.id
                      ? "保存中…"
                      : masked
                        ? "更新凭据"
                        : "添加凭据"}
                  </button>
                  <button
                    type="button"
                    onClick={() => testConnection(prov.id)}
                    disabled={testingId === prov.id}
                    className="rounded border border-line px-3 py-1.5 text-sm text-ink disabled:opacity-40"
                  >
                    {testingId === prov.id ? "测试中…" : "测试连接"}
                  </button>
                </div>
                {result ? (
                  <div className="mt-2 flex items-center gap-2 pl-5">
                    <span
                      className={`text-xs ${result.ok ? "text-pass" : "text-conflict"}`}
                    >
                      {result.ok ? "✓ 已连接" : "✗ 未连接"}
                    </span>
                    <CapabilityBadges caps={result.capabilities} />
                  </div>
                ) : null}
              </li>
            );
          })}
        </ul>
      </section>
    </div>
  );
}

function CapabilityBadges({ caps }: { caps: CapabilitiesView }) {
  const badges: { on: boolean; label: string }[] = [
    { on: caps.structured_output, label: "结构化" },
    { on: caps.prefix_cache, label: "前缀缓存" },
    { on: caps.thinking, label: "思考" },
  ];
  return (
    <div className="flex gap-1.5">
      {badges.map((b) => (
        <span
          key={b.label}
          className={`rounded px-2 py-0.5 text-[11px] ${
            b.on
              ? "bg-[var(--color-cinnabar-wash)] text-cinnabar"
              : "bg-bg text-ink-soft/50"
          }`}
        >
          {b.label}
        </span>
      ))}
    </div>
  );
}