import { useState, useEffect, useCallback } from "react";
import { get, post, put, del } from "../lib/api";
import DataTable, { type Column } from "../components/DataTable";
import Modal from "../components/Modal";

interface GameClass {
  id: string;
  name: string;
  balance: string;
  roleId: string | null;
}

interface ClassesResponse {
  classes: GameClass[];
}

export default function Classes() {
  const [classes, setClasses] = useState<GameClass[]>([]);
  const [loading, setLoading] = useState(true);
  const [modalOpen, setModalOpen] = useState(false);
  const [editing, setEditing] = useState<GameClass | null>(null);
  const [form, setForm] = useState<{ id?: string; name: string; balance: string; roleId: string | null }>({ name: "", balance: "0", roleId: null });
  const [saving, setSaving] = useState(false);

  const fetchClasses = useCallback(() => {
    setLoading(true);
    get<ClassesResponse>("/api/classes")
      .then((data) => setClasses(data.classes))
      .catch(() => {})
      .finally(() => setLoading(false));
  }, []);

  useEffect(() => { fetchClasses(); }, [fetchClasses]);

  const openCreate = () => {
    setEditing(null);
    setForm({ id: "", name: "", balance: "0", roleId: null });
    setModalOpen(true);
  };

  const openEdit = (cls: GameClass) => {
    setEditing(cls);
    setForm({ name: cls.name, balance: cls.balance, roleId: cls.roleId });
    setModalOpen(true);
  };

  const handleSave = async () => {
    setSaving(true);
    try {
      if (editing) {
        await put(`/api/classes/${editing.id}`, { name: form.name, balance: form.balance, roleId: form.roleId });
      } else {
        await post("/api/classes", { id: form.id, name: form.name, balance: form.balance, roleId: form.roleId });
      }
      setModalOpen(false);
      fetchClasses();
    } catch (e) {
      alert(typeof e === "object" && e && "error" in e ? (e as { error: string }).error : "Failed to save");
    } finally {
      setSaving(false);
    }
  };

  const handleDelete = async (cls: GameClass) => {
    if (!confirm(`Delete "${cls.name}"?`)) return;
    await del(`/api/classes/${cls.id}`);
    fetchClasses();
  };

  const columns: Column<GameClass>[] = [
    { key: "id", header: "ID", className: "w-24" },
    { key: "name", header: "Name" },
    { key: "balance", header: "Balance", render: (r) => BigInt(r.balance).toLocaleString() },
    { key: "roleId", header: "Role ID", render: (r) => r.roleId ?? "—" },
    {
      key: "actions",
      header: "",
      className: "w-24",
      render: (row) => (
        <div className="flex gap-1">
          <button className="btn btn-ghost btn-xs" onClick={(e) => { e.stopPropagation(); openEdit(row); }}>Edit</button>
          <button className="btn btn-ghost btn-xs text-error" onClick={(e) => { e.stopPropagation(); handleDelete(row); }}>Del</button>
        </div>
      ),
    },
  ];

  return (
    <div>
      <div className="flex items-center justify-between mb-4">
        <h1 className="text-2xl font-bold">Classes</h1>
        <button className="btn btn-primary btn-sm" onClick={openCreate}>+ New Class</button>
      </div>

      <DataTable columns={columns} data={classes as unknown as Record<string, unknown>[]} keyField="id" loading={loading} />

      <Modal
        open={modalOpen}
        onClose={() => setModalOpen(false)}
        title={editing ? `Edit: ${editing.name}` : "New Class"}
        actions={
          <>
            <button className="btn btn-ghost" onClick={() => setModalOpen(false)}>Cancel</button>
            <button className="btn btn-primary" onClick={handleSave} disabled={saving}>
              {saving ? <span className="loading loading-spinner loading-sm" /> : "Save"}
            </button>
          </>
        }
      >
        <div className="space-y-3">
          {!editing && (
            <div className="form-control">
              <label className="label"><span className="label-text">ID (Discord role snowflake or unique number)</span></label>
              <input className="input input-bordered input-sm" value={form.id ?? ""} onChange={(e) => setForm({ ...form, id: e.target.value })} />
            </div>
          )}
          <div className="form-control">
            <label className="label"><span className="label-text">Name</span></label>
            <input className="input input-bordered input-sm" maxLength={50} value={form.name} onChange={(e) => setForm({ ...form, name: e.target.value })} />
          </div>
          <div className="form-control">
            <label className="label"><span className="label-text">Balance</span></label>
            <input className="input input-bordered input-sm" value={form.balance} onChange={(e) => setForm({ ...form, balance: e.target.value })} />
          </div>
          <div className="form-control">
            <label className="label"><span className="label-text">Role ID (Discord)</span></label>
            <input className="input input-bordered input-sm" placeholder="Optional" value={form.roleId ?? ""} onChange={(e) => setForm({ ...form, roleId: e.target.value || null })} />
          </div>
        </div>
      </Modal>
    </div>
  );
}