"use client";

import { useState } from "react";
import {
  Card,
  CardAction,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card";
import { Button } from "@/components/ui/button";
import { Badge } from "@/components/ui/badge";
import {
  Field,
  FieldDescription,
  FieldGroup,
  FieldLabel,
} from "@/components/ui/field";
import { Input } from "@/components/ui/input";
import { Spinner } from "@/components/ui/spinner";
import { Bomb, RefreshCw } from "lucide-react";
import { forceRefresh, refetchPlatform } from "./actions";
import { toast } from "sonner";

interface Platform {
  name: string;
  cachedCount: number | null;
}

function formatCount(n: number | null): string {
  if (n === null) return "No data";
  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1)}M`;
  if (n >= 1_000) return `${(n / 1_000).toFixed(1)}K`;
  return n.toString();
}

export function BackendClient({ platforms }: { platforms: Platform[] }) {
  const [data, setData] = useState<Platform[]>(platforms);
  const [loading, setLoading] = useState<string | null>(null);
  const [pathPrefix, setPathPrefix] = useState("");
  const [reloadTarget, setReloadTarget] = useState<"all" | "path" | null>(null);

  const handleRefetch = async (platform: string) => {
    setLoading(platform);
    try {
      const result = await refetchPlatform(platform);
      setData((prev) =>
        prev.map((p) =>
          p.name === platform ? { ...p, cachedCount: result.count } : p
        )
      );
      toast.success(`${platform} refetched successfully`);
    } catch {
      toast.error(`Failed to refetch ${platform}`);
    } finally {
      setLoading(null);
    }
  };

  const handleForceRefresh = async (
    target: "all" | "path",
    prefix: string | null,
  ) => {
    setReloadTarget(target);
    try {
      await forceRefresh(prefix);
      toast.success(
        prefix ? `Reload sent for ${prefix}` : "Reload sent to all clients",
      );
    } catch (error) {
      toast.error(error instanceof Error ? error.message : "Failed to send reload");
    } finally {
      setReloadTarget(null);
    }
  };

  const normalizedPathPrefix = pathPrefix.trim();
  const pathIsValid = normalizedPathPrefix.startsWith("/");

  return (
    <div className="flex flex-col gap-4">
      <div className="grid gap-4 sm:grid-cols-2">
        {data.map((p) => (
          <Card key={p.name}>
            <CardHeader>
              <CardTitle className="text-sm font-medium capitalize">
                {p.name}
              </CardTitle>
              <CardAction>
                <Badge
                  variant={p.cachedCount !== null ? "default" : "secondary"}
                >
                  {formatCount(p.cachedCount)}
                </Badge>
              </CardAction>
            </CardHeader>
            <CardContent>
              <Button
                variant="outline"
                size="sm"
                disabled={loading !== null}
                onClick={() => handleRefetch(p.name)}
              >
                {loading === p.name ? (
                  <Spinner data-icon="inline-start" />
                ) : (
                  <RefreshCw data-icon="inline-start" />
                )}
                Refetch
              </Button>
            </CardContent>
          </Card>
        ))}
      </div>

      <Card>
        <CardHeader>
          <CardTitle>Client reload</CardTitle>
          <CardDescription>
            Reload every connected client or only clients under a pathname prefix.
          </CardDescription>
        </CardHeader>
        <CardContent>
          <Button
            variant="destructive"
            disabled={reloadTarget !== null}
            onClick={() => handleForceRefresh("all", null)}
          >
            {reloadTarget === "all" ? (
              <Spinner data-icon="inline-start" />
            ) : (
              <Bomb data-icon="inline-start" />
            )}
            Force reload all
          </Button>

          <FieldGroup>
            <Field data-invalid={pathPrefix.length > 0 && !pathIsValid}>
              <FieldLabel htmlFor="reload-path-prefix">Path prefix</FieldLabel>
              <Input
                id="reload-path-prefix"
                value={pathPrefix}
                onChange={(event) => setPathPrefix(event.target.value)}
                placeholder="/admin"
                aria-invalid={pathPrefix.length > 0 && !pathIsValid}
              />
              <FieldDescription>
                Reloads clients whose pathname starts with this value.
              </FieldDescription>
            </Field>
            <Button
              variant="destructive"
              disabled={reloadTarget !== null || !pathIsValid}
              onClick={() => handleForceRefresh("path", normalizedPathPrefix)}
            >
              {reloadTarget === "path" ? (
                <Spinner data-icon="inline-start" />
              ) : (
                <Bomb data-icon="inline-start" />
              )}
              Reload matching path
            </Button>
          </FieldGroup>
        </CardContent>
      </Card>
    </div>
  );
}