"use client";

import { FormEvent, useCallback, useEffect, useMemo, useState } from "react";
import Link from "next/link";
import {
  AdminPageHeader,
  Banner,
  Button,
  EmptyState,
  Modal,
  StatusBadge,
  TextareaField,
} from "@/components/admin/controls";
import type { CommercialAdminResourceDef } from "../admin/resources";
import {
  createAdminRegistryItem,
  deleteAdminRegistryItem,
  listAdminRegistry,
  type RegistryRecord,
  updateAdminRegistryItem,
} from "../adapters/admin";
import type { AdapterResult } from "../types";

function recordLabel(item: RegistryRecord, resource: CommercialAdminResourceDef): string {
  const name = item[resource.nameField];
  if (typeof name === "string" && name) return name;
  const code = item[resource.codeField];
  if (typeof code === "string" || typeof code === "number") return String(code);
  return "—";
}

function recordCode(item: RegistryRecord, resource: CommercialAdminResourceDef): string {
  const code = item[resource.codeField];
  return code == null ? "" : String(code);
}

function defaultCreateJson(resource: CommercialAdminResourceDef): string {
  const seed: RegistryRecord = {
    [resource.codeField]: "",
    [resource.nameField]: "",
    status: "draft",
  };
  if (resource.key === "products") {
    seed.visibility = "public";
    seed.launch_strategy = "route";
    seed.default_route = "";
    seed.product_slug = "";
    seed.display_order = 0;
  }
  if (resource.key === "trial-rules") {
    seed.duration_days = 14;
    seed.grace_period_days = 3;
    seed.usage_limits = {};
    seed.feature_limits = {};
    seed.expiration_behavior = "lock";
    seed.auto_disable = true;
  }
  if (resource.key === "policies") {
    seed.policy_kind = "domain";
    seed.effect = "deny";
    seed.parameters = {
      custom_domain_allowed: false,
      subdomain_only: true,
      ssl_ready: false,
      dns_instructions: [],
    };
  }
  return JSON.stringify(seed, null, 2);
}

export function AdminRegistryManager({ resource }: { resource: CommercialAdminResourceDef }) {
  const [result, setResult] = useState<AdapterResult<RegistryRecord[]> | null>(null);
  const [error, setError] = useState("");
  const [msg, setMsg] = useState("");
  const [loading, setLoading] = useState(true);
  const [createOpen, setCreateOpen] = useState(false);
  const [editItem, setEditItem] = useState<RegistryRecord | null>(null);
  const [jsonBody, setJsonBody] = useState("");
  const [busy, setBusy] = useState(false);

  const load = useCallback(async () => {
    setLoading(true);
    setError("");
    const r = await listAdminRegistry(resource);
    setResult(r);
    if (r.availability === "unavailable" || r.availability === "permission_denied" || r.availability === "error") {
      setError(r.message || "رجیستری در دسترس نیست");
    }
    setLoading(false);
  }, [resource]);

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

  const items = result?.data ?? [];

  const openCreate = () => {
    setJsonBody(defaultCreateJson(resource));
    setCreateOpen(true);
    setMsg("");
    setError("");
  };

  const openEdit = (item: RegistryRecord) => {
    setEditItem(item);
    setJsonBody(JSON.stringify(item, null, 2));
    setMsg("");
    setError("");
  };

  const submitCreate = async (e: FormEvent) => {
    e.preventDefault();
    setBusy(true);
    setError("");
    try {
      const body = JSON.parse(jsonBody) as RegistryRecord;
      const res = await createAdminRegistryItem(resource, body);
      if (!res.ok) {
        setError(res.message);
        return;
      }
      setCreateOpen(false);
      setMsg("ثبت شد — tenant UI از همین رجیستری می‌خواند.");
      await load();
    } catch {
      setError("JSON نامعتبر است");
    } finally {
      setBusy(false);
    }
  };

  const submitEdit = async (e: FormEvent) => {
    e.preventDefault();
    if (!editItem) return;
    setBusy(true);
    setError("");
    try {
      const body = JSON.parse(jsonBody) as RegistryRecord;
      const code = recordCode(editItem, resource) || String(body[resource.codeField] ?? "");
      if (!code) {
        setError("کد رکورد مشخص نیست");
        return;
      }
      const res = await updateAdminRegistryItem(resource, code, body);
      if (!res.ok) {
        setError(res.message);
        return;
      }
      setEditItem(null);
      setMsg("به‌روزرسانی شد — تغییرات بلافاصله در tenant قابل مشاهده است.");
      await load();
    } catch {
      setError("JSON نامعتبر است");
    } finally {
      setBusy(false);
    }
  };

  const onDelete = async (item: RegistryRecord) => {
    const code = recordCode(item, resource);
    if (!code) return;
    if (!window.confirm(`حذف ${code}؟`)) return;
    setBusy(true);
    const res = await deleteAdminRegistryItem(resource, code);
    if (!res.ok) setError(res.message);
    else {
      setMsg("حذف شد");
      await load();
    }
    setBusy(false);
  };

  const availabilityHint = useMemo(() => {
    if (!result) return null;
    if (result.availability === "unavailable") {
      return "Core Commercial API هنوز در دسترس نیست — بدون داده جعلی.";
    }
    if (result.availability === "empty") return "رجیستری خالی است.";
    if (result.availability === "permission_denied") return "دسترسی تجاری ندارید.";
    return null;
  }, [result]);

  return (
    <div className="space-y-6">
      <AdminPageHeader
        title={resource.label}
        subtitle={resource.description}
        action={
          <div className="flex flex-wrap gap-2">
            <Link href="/admin/commercial">
              <Button variant="outline">بازگشت</Button>
            </Link>
            <Button onClick={openCreate}>افزودن / ثبت</Button>
          </div>
        }
      />

      {error ? <Banner variant="error">{error}</Banner> : null}
      {msg ? <Banner variant="success">{msg}</Banner> : null}
      {availabilityHint ? <Banner variant="info">{availabilityHint}</Banner> : null}

      <p className="font-mono text-[11px] text-gray-400" dir="ltr">
        {resource.listPath}
      </p>

      <section className="overflow-hidden rounded-2xl border border-gray-100 bg-white shadow-sm">
        {loading ? (
          <EmptyState message="در حال بارگذاری..." />
        ) : items.length === 0 ? (
          <EmptyState message={result?.message || "موردی در رجیستری نیست."} />
        ) : (
          <div className="overflow-x-auto">
            <table className="w-full min-w-[720px] text-sm">
              <thead className="bg-gray-50 text-right">
                <tr>
                  <th className="px-4 py-3 font-semibold text-secondary">نام</th>
                  <th className="px-4 py-3 font-semibold text-secondary">کد</th>
                  <th className="px-4 py-3 font-semibold text-secondary">وضعیت</th>
                  <th className="px-4 py-3 font-semibold text-secondary">عملیات</th>
                </tr>
              </thead>
              <tbody>
                {items.map((item, idx) => {
                  const code = recordCode(item, resource) || String(idx);
                  const status = typeof item.status === "string" ? item.status : "—";
                  return (
                    <tr key={code} className="border-t border-gray-100">
                      <td className="px-4 py-3 font-medium text-secondary">
                        {recordLabel(item, resource)}
                      </td>
                      <td className="px-4 py-3 font-mono text-xs text-gray-600" dir="ltr">
                        {code}
                      </td>
                      <td className="px-4 py-3">
                        <StatusBadge status={status === "—" ? "inactive" : status} />
                      </td>
                      <td className="px-4 py-3">
                        <div className="flex flex-wrap gap-2">
                          <Button variant="outline" size="sm" onClick={() => openEdit(item)}>
                            ویرایش
                          </Button>
                          <Button
                            variant="outline"
                            size="sm"
                            disabled={busy}
                            onClick={() => void onDelete(item)}
                          >
                            حذف
                          </Button>
                        </div>
                      </td>
                    </tr>
                  );
                })}
              </tbody>
            </table>
          </div>
        )}
      </section>

      <Modal open={createOpen} onClose={() => setCreateOpen(false)} title={`ثبت ${resource.label}`}>
        <form onSubmit={(e) => void submitCreate(e)} className="space-y-4">
          <p className="text-xs text-gray-500">
            بدنه JSON مستقیم به API رجیستری ارسال می‌شود — هیچ کاتالوگ ثابتی در frontend نیست.
          </p>
          <TextareaField
            label="Payload (JSON)"
            value={jsonBody}
            onValue={setJsonBody}
            rows={16}
            dir="ltr"
            className="font-mono text-xs"
          />
          <div className="flex justify-end gap-2">
            <Button type="button" variant="outline" onClick={() => setCreateOpen(false)}>
              انصراف
            </Button>
            <Button type="submit" loading={busy}>
              ثبت در رجیستری
            </Button>
          </div>
        </form>
      </Modal>

      <Modal
        open={Boolean(editItem)}
        onClose={() => setEditItem(null)}
        title={`ویرایش ${resource.label}`}
      >
        <form onSubmit={(e) => void submitEdit(e)} className="space-y-4">
          <TextareaField
            label="Payload (JSON)"
            value={jsonBody}
            onValue={setJsonBody}
            rows={16}
            dir="ltr"
            className="font-mono text-xs"
          />
          <div className="flex justify-end gap-2">
            <Button type="button" variant="outline" onClick={() => setEditItem(null)}>
              انصراف
            </Button>
            <Button type="submit" loading={busy}>
              ذخیره
            </Button>
          </div>
        </form>
      </Modal>
    </div>
  );
}