"use client";

import { useState, type FormEvent } from "react";
import { useRouter } from "next/navigation";
import type { Banner } from "@/types/cms";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { useConfirmDialog } from "@/components/ui/confirm-dialog";
import { useToast } from "@/components/ui/toast";
import { cardClasses } from "@/components/ui/styles";
import { cn } from "@/lib/utils";
import { clientFetch } from "@/lib/api/client";

interface BannerFormState {
  title: string;
  image_url: string;
  link_url: string;
  display_order: string;
  is_active: boolean;
}

const EMPTY_FORM: BannerFormState = {
  title: "",
  image_url: "",
  link_url: "",
  display_order: "0",
  is_active: true,
};

export function BannerManager({ banners }: { banners: Banner[] }) {
  const router = useRouter();
  const [showCreate, setShowCreate] = useState(false);
  const [createForm, setCreateForm] = useState<BannerFormState>(EMPTY_FORM);
  const [editingId, setEditingId] = useState<number | null>(null);
  const [editForm, setEditForm] = useState<BannerFormState>(EMPTY_FORM);
  const [error, setError] = useState<string | null>(null);
  const [isSubmitting, setIsSubmitting] = useState(false);
  const [deletingId, setDeletingId] = useState<number | null>(null);
  const { confirm, dialog } = useConfirmDialog();
  const { toast } = useToast();

  function toPayload(form: BannerFormState) {
    return {
      title: form.title || null,
      image_url: form.image_url,
      link_url: form.link_url || null,
      display_order: form.display_order ? Number(form.display_order) : 0,
      is_active: form.is_active,
    };
  }

  async function handleCreate(formEvent: FormEvent<HTMLFormElement>) {
    formEvent.preventDefault();
    setError(null);
    setIsSubmitting(true);

    const res = await clientFetch("/api/admin/cms/banners", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(toPayload(createForm)),
    });

    setIsSubmitting(false);
    const body = await res.json().catch(() => null);

    if (!res.ok) {
      const message = body?.message ?? "Failed to create banner.";
      setError(message);
      toast(message, "error");
      return;
    }

    setShowCreate(false);
    setCreateForm(EMPTY_FORM);
    toast("Banner created successfully.", "success");
    router.refresh();
  }

  async function handleUpdate(formEvent: FormEvent<HTMLFormElement>, id: number) {
    formEvent.preventDefault();
    setError(null);
    setIsSubmitting(true);

    const res = await clientFetch(`/api/admin/cms/banners/${id}`, {
      method: "PUT",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(toPayload(editForm)),
    });

    setIsSubmitting(false);
    const body = await res.json().catch(() => null);

    if (!res.ok) {
      const message = body?.message ?? "Failed to update banner.";
      setError(message);
      toast(message, "error");
      return;
    }

    setEditingId(null);
    toast("Banner updated successfully.", "success");
    router.refresh();
  }

  async function handleDelete(id: number) {
    if (!(await confirm("Delete this banner?"))) return;

    setError(null);
    setDeletingId(id);
    const res = await clientFetch(`/api/admin/cms/banners/${id}`, { method: "DELETE" });
    setDeletingId(null);
    const body = await res.json().catch(() => null);

    if (!res.ok) {
      const message = body?.message ?? "Failed to delete banner.";
      setError(message);
      toast(message, "error");
      return;
    }
    toast("Banner deleted successfully.", "success");
    router.refresh();
  }

  return (
    <div>
      {dialog}
      {error && <p className="mb-3 text-sm text-red-600">{error}</p>}

      <div className={cn("flex flex-col divide-y divide-kolabora-neutral-dark/10", cardClasses())}>
        {banners.length === 0 && (
          <p className="px-4 py-6 text-center text-sm text-kolabora-neutral-dark/70">No banners yet.</p>
        )}
        {banners.map((banner) =>
          editingId === banner.id ? (
            <form
              key={banner.id}
              onSubmit={(e) => handleUpdate(e, banner.id)}
              className="flex flex-col gap-2 px-4 py-3"
            >
              <Input
                size="sm"
                value={editForm.title}
                onChange={(e) => setEditForm({ ...editForm, title: e.target.value })}
                placeholder="Title (optional)"
              />
              <Input
                size="sm"
                required
                value={editForm.image_url}
                onChange={(e) => setEditForm({ ...editForm, image_url: e.target.value })}
                placeholder="Image URL"
              />
              <Input
                size="sm"
                value={editForm.link_url}
                onChange={(e) => setEditForm({ ...editForm, link_url: e.target.value })}
                placeholder="Link URL (optional)"
              />
              <div className="flex items-center gap-3">
                <Input
                  size="sm"
                  type="number"
                  value={editForm.display_order}
                  onChange={(e) => setEditForm({ ...editForm, display_order: e.target.value })}
                  placeholder="Order"
                  className="w-24"
                />
                <label className="flex items-center gap-1.5 text-sm">
                  <input
                    type="checkbox"
                    checked={editForm.is_active}
                    onChange={(e) => setEditForm({ ...editForm, is_active: e.target.checked })}
                  />
                  Active
                </label>
                <Button type="submit" size="sm" loading={isSubmitting} className="ml-auto">
                  Save
                </Button>
                <Button
                  type="button"
                  variant="secondary"
                  size="sm"
                  onClick={() => setEditingId(null)}
                  disabled={isSubmitting}
                >
                  Cancel
                </Button>
              </div>
            </form>
          ) : (
            <div key={banner.id} className="flex items-center justify-between gap-3 px-4 py-3">
              <div className="flex items-center gap-3">
                {/* eslint-disable-next-line @next/next/no-img-element -- admin-provided URL, not on next/image allowlist */}
                <img
                  src={banner.image_url}
                  alt={banner.title ?? "Banner"}
                  className="h-12 w-24 rounded-lg object-cover"
                />
                <div>
                  <p className="font-medium">{banner.title ?? "(untitled)"}</p>
                  <p className="text-xs text-kolabora-neutral-dark/70">Order: {banner.display_order}</p>
                  {!banner.is_active && (
                    <span className="mt-1 inline-block rounded-full bg-kolabora-neutral-dark/10 px-2 py-0.5 text-xs">
                      Inactive
                    </span>
                  )}
                </div>
              </div>
              <div className="flex shrink-0 gap-2">
                <Button
                  type="button"
                  variant="secondary"
                  size="sm"
                  onClick={() => {
                    setEditingId(banner.id);
                    setEditForm({
                      title: banner.title ?? "",
                      image_url: banner.image_url,
                      link_url: banner.link_url ?? "",
                      display_order: String(banner.display_order),
                      is_active: banner.is_active,
                    });
                  }}
                >
                  Edit
                </Button>
                <Button
                  type="button"
                  variant="danger"
                  size="sm"
                  onClick={() => handleDelete(banner.id)}
                  loading={deletingId === banner.id}
                >
                  Delete
                </Button>
              </div>
            </div>
          ),
        )}
      </div>

      {showCreate ? (
        <form
          onSubmit={handleCreate}
          className={cn("mt-4 flex flex-col gap-2", cardClasses("p-4"))}
        >
          <Input
            value={createForm.title}
            onChange={(e) => setCreateForm({ ...createForm, title: e.target.value })}
            placeholder="Title (optional)"
          />
          <Input
            required
            value={createForm.image_url}
            onChange={(e) => setCreateForm({ ...createForm, image_url: e.target.value })}
            placeholder="Image URL"
          />
          <Input
            value={createForm.link_url}
            onChange={(e) => setCreateForm({ ...createForm, link_url: e.target.value })}
            placeholder="Link URL (optional)"
          />
          <div className="flex items-center gap-3">
            <Input
              type="number"
              value={createForm.display_order}
              onChange={(e) => setCreateForm({ ...createForm, display_order: e.target.value })}
              placeholder="Order"
              className="w-24"
            />
            <label className="flex items-center gap-1.5 text-sm">
              <input
                type="checkbox"
                checked={createForm.is_active}
                onChange={(e) => setCreateForm({ ...createForm, is_active: e.target.checked })}
              />
              Active
            </label>
            <Button type="submit" loading={isSubmitting} className="ml-auto">
              Save
            </Button>
            <Button type="button" variant="secondary" onClick={() => setShowCreate(false)} disabled={isSubmitting}>
              Cancel
            </Button>
          </div>
        </form>
      ) : (
        <Button type="button" onClick={() => setShowCreate(true)} className="mt-4">
          + Add Banner
        </Button>
      )}
    </div>
  );
}