"use client";

import { useEffect, useRef, useState } from "react";
import { useTranslation } from "react-i18next";
import { IconLoader2 } from "@tabler/icons-react";
import { Button } from "@kandev/ui/button";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@kandev/ui/dialog";
import { Input } from "@kandev/ui/input";
import { Label } from "@kandev/ui/label";
import { Tabs, TabsContent, TabsList, TabsTrigger } from "@kandev/ui/tabs";
import { cn } from "@/lib/utils";

type InstallTab = "url" | "upload";

type InstallPluginDialogProps = {
  open: boolean;
  busy: boolean;
  error: string | null;
  onOpenChange: (open: boolean) => void;
  onSubmitUrl: (url: string) => void;
  onSubmitFile: (file: File) => void;
};

/**
 * Replaces the old "Register plugin" manifest-paste dialog with the
 * install-based flow (docs/plans/plugins/GRPC-CONTRACT.md §7): install from a
 * remote tarball URL, or upload a .tar.gz package directly. No credentials
 * are ever shown — installing a plugin has nothing to copy or reveal.
 */
export function InstallPluginDialog({
  open,
  busy,
  error,
  onOpenChange,
  onSubmitUrl,
  onSubmitFile,
}: InstallPluginDialogProps) {
  const { t } = useTranslation();
  const [tab, setTab] = useState<InstallTab>("url");
  const [url, setUrl] = useState("");
  const [file, setFile] = useState<File | null>(null);

  // Reset the lifted input state whenever the dialog closes. This keys off the
  // `open` prop rather than `onOpenChange` because a successful install closes
  // the dialog by flipping the controlled `open` prop directly
  // (usePluginActions.afterInstall), which never routes through onOpenChange —
  // so resetting only in an onOpenChange handler would leave a stale file/url
  // selected the next time the dialog opens.
  useEffect(() => {
    if (!open) {
      setUrl("");
      setFile(null);
      setTab("url");
    }
  }, [open]);

  const trimmedUrl = url.trim();
  // The single Install button submits whichever tab is active; its testid,
  // handler, and disabled state all derive from `tab` so the e2e/unit selectors
  // (install-plugin-url-submit / install-plugin-upload-submit) keep working.
  const install =
    tab === "url"
      ? {
          testId: "install-plugin-url-submit",
          onClick: () => onSubmitUrl(trimmedUrl),
          disabled: busy || trimmedUrl.length === 0,
        }
      : {
          testId: "install-plugin-upload-submit",
          onClick: () => file && onSubmitFile(file),
          disabled: busy || !file,
        };

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent className="sm:max-w-lg" data-testid="install-plugin-dialog">
        <DialogHeader>
          <DialogTitle>{t("plugins:installPlugin")}</DialogTitle>
          <DialogDescription>
            {/* `.tar.gz` is a file extension, interpolated so the
                pseudo-locale cannot transliterate it. */}
            {t("plugins:installPluginDescription", { extension: ".tar.gz" })}
          </DialogDescription>
        </DialogHeader>

        <Tabs value={tab} onValueChange={(v) => setTab(v as InstallTab)}>
          <TabsList>
            <TabsTrigger
              value="url"
              className="cursor-pointer"
              data-testid="install-plugin-tab-url"
            >
              {t("plugins:fromUrl")}
            </TabsTrigger>
            <TabsTrigger
              value="upload"
              className="cursor-pointer"
              data-testid="install-plugin-tab-upload"
            >
              {t("plugins:uploadFile")}
            </TabsTrigger>
          </TabsList>
          <TabsContent value="url" className="pt-3">
            <UrlTab url={url} setUrl={setUrl} />
          </TabsContent>
          <TabsContent value="upload" className="pt-3">
            <UploadTab file={file} setFile={setFile} />
          </TabsContent>
        </Tabs>

        {error && (
          <div data-testid="install-plugin-error" className="text-xs text-destructive" role="alert">
            {error}
          </div>
        )}

        <DialogFooter>
          <Button
            type="button"
            variant="outline"
            onClick={() => onOpenChange(false)}
            className="cursor-pointer"
          >
            {t("plugins:cancel")}
          </Button>
          <Button
            type="button"
            data-testid={install.testId}
            onClick={install.onClick}
            disabled={install.disabled}
            aria-busy={busy || undefined}
            className="cursor-pointer"
          >
            {busy ? <IconLoader2 className="h-4 w-4 animate-spin" aria-hidden="true" /> : null}
            {busy ? t("plugins:installing") : t("plugins:install")}
          </Button>
        </DialogFooter>
      </DialogContent>
    </Dialog>
  );
}

function UrlTab({ url, setUrl }: { url: string; setUrl: (v: string) => void }) {
  const { t } = useTranslation();
  return (
    <div className="space-y-1.5">
      <Label htmlFor="install-plugin-url">{t("plugins:packageUrl")}</Label>
      <Input
        id="install-plugin-url"
        data-testid="install-plugin-url-input"
        value={url}
        onChange={(e) => setUrl(e.target.value)}
        placeholder="https://example.com/acme-tools-1.0.0.tar.gz"
        className="font-mono text-sm"
      />
    </div>
  );
}

function UploadTab({ file, setFile }: { file: File | null; setFile: (file: File | null) => void }) {
  const { t } = useTranslation();
  const inputRef = useRef<HTMLInputElement>(null);
  const [isDragging, setIsDragging] = useState(false);

  const handleDragOver = (e: React.DragEvent) => {
    e.preventDefault();
    e.stopPropagation();
  };

  const handleDragEnter = (e: React.DragEvent) => {
    e.preventDefault();
    e.stopPropagation();
    if (e.dataTransfer.types.includes("Files")) setIsDragging(true);
  };

  const handleDragLeave = (e: React.DragEvent) => {
    e.preventDefault();
    e.stopPropagation();
    setIsDragging(false);
  };

  const handleDrop = (e: React.DragEvent) => {
    e.preventDefault();
    e.stopPropagation();
    setIsDragging(false);
    const dropped = e.dataTransfer.files[0];
    if (dropped) setFile(dropped);
  };

  return (
    <div
      data-testid="install-plugin-dropzone"
      onDragOver={handleDragOver}
      onDragEnter={handleDragEnter}
      onDragLeave={handleDragLeave}
      onDrop={handleDrop}
      onClick={() => inputRef.current?.click()}
      className={cn(
        "flex flex-col items-center justify-center gap-2 rounded-lg border border-dashed border-border/70 p-6 text-center text-sm text-muted-foreground cursor-pointer",
        isDragging && "border-primary bg-primary/5 ring-1 ring-primary/30",
      )}
    >
      <span>
        {file ? (
          <span className="font-mono text-foreground">{file.name}</span>
        ) : (
          t("plugins:dropzoneHint", { extension: ".tar.gz" })
        )}
      </span>
      <input
        ref={inputRef}
        type="file"
        accept=".tar.gz,.tgz,application/gzip"
        data-testid="install-plugin-file-input"
        onChange={(e) => setFile(e.target.files?.[0] ?? null)}
        className="hidden"
      />
    </div>
  );
}