import { useState } from "react";
import { useQueryClient } from "@tanstack/react-query";
import { Archive, Upload } from "lucide-react";
import { toast } from "sonner";
import { Button } from "@/components/ui";
import { backupsApi } from "@/api/backups";
import { apiErrorMessage } from "@/api/client";

function Checkbox({
  checked,
  onChange,
  label,
  hint,
}: {
  checked: boolean;
  onChange: (v: boolean) => void;
  label: string;
  hint?: string;
}) {
  return (
    <label className="flex items-start gap-2 text-sm">
      <input
        type="checkbox"
        checked={checked}
        onChange={(e) => onChange(e.target.checked)}
        className="mt-0.5 h-4 w-4 rounded border-slate-300 text-accent"
      />
      <span>
        {label}
        {hint && <span className="block text-xs text-slate-500">{hint}</span>}
      </span>
    </label>
  );
}

function Modal({ children, onClose }: { children: React.ReactNode; onClose: () => void }) {
  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50 p-4" onClick={onClose}>
      <div
        className="w-full max-w-md rounded-xl border border-slate-200 bg-card p-5 shadow-xl dark:border-slate-700 dark:bg-card-dark"
        onClick={(e) => e.stopPropagation()}
      >
        {children}
      </div>
    </div>
  );
}

export function BackupButton({ stackId }: { stackId: string }) {
  const [open, setOpen] = useState(false);
  const [includeVolumes, setIncludeVolumes] = useState(true);
  const [stopFirst, setStopFirst] = useState(true);
  const [busy, setBusy] = useState(false);

  const run = async () => {
    setBusy(true);
    const tid = toast.loading("Creating backup…");
    try {
      await backupsApi.download(stackId, { includeVolumes, stopFirst });
      toast.success("Backup downloaded", { id: tid });
      setOpen(false);
    } catch (e) {
      toast.error(apiErrorMessage(e), { id: tid });
    } finally {
      setBusy(false);
    }
  };

  return (
    <>
      <Button variant="outline" onClick={() => setOpen(true)}>
        <Archive className="h-4 w-4" /> Backup
      </Button>
      {open && (
        <Modal onClose={() => !busy && setOpen(false)}>
          <h2 className="mb-3 text-lg font-semibold">Back up “{stackId}”</h2>
          <div className="space-y-3">
            <Checkbox
              checked={includeVolumes}
              onChange={setIncludeVolumes}
              label="Include named volume data"
              hint="Snapshots each compose-managed volume into the archive."
            />
            <Checkbox
              checked={stopFirst}
              onChange={setStopFirst}
              label="Stop the stack during backup"
              hint="Recommended for a consistent volume snapshot; the stack is restarted afterwards."
            />
          </div>
          <div className="mt-4 flex justify-end gap-2">
            <Button variant="outline" onClick={() => setOpen(false)} disabled={busy}>
              Cancel
            </Button>
            <Button onClick={run} loading={busy}>
              Download backup
            </Button>
          </div>
        </Modal>
      )}
    </>
  );
}

export function RestoreButton() {
  const qc = useQueryClient();
  const [open, setOpen] = useState(false);
  const [file, setFile] = useState<File | null>(null);
  const [targetId, setTargetId] = useState("");
  const [overwrite, setOverwrite] = useState(false);
  const [restoreVolumes, setRestoreVolumes] = useState(true);
  const [busy, setBusy] = useState(false);

  const run = async () => {
    if (!file) {
      toast.error("Select a backup file");
      return;
    }
    setBusy(true);
    const tid = toast.loading("Restoring…");
    try {
      const res = await backupsApi.restore(file, {
        targetId: targetId.trim() || undefined,
        overwrite,
        restoreVolumes,
      });
      toast.success(
        `Restored '${res.stack_id}' (${res.volumes_restored} volume(s))`,
        { id: tid }
      );
      qc.invalidateQueries({ queryKey: ["stacks"] });
      setOpen(false);
      setFile(null);
      setTargetId("");
    } catch (e) {
      toast.error(apiErrorMessage(e), { id: tid });
    } finally {
      setBusy(false);
    }
  };

  return (
    <>
      <Button variant="outline" onClick={() => setOpen(true)}>
        <Upload className="h-4 w-4" /> Restore
      </Button>
      {open && (
        <Modal onClose={() => !busy && setOpen(false)}>
          <h2 className="mb-3 text-lg font-semibold">Restore from backup</h2>
          <div className="space-y-3">
            <input
              type="file"
              accept=".tar.gz,.tgz,application/gzip"
              onChange={(e) => setFile(e.target.files?.[0] ?? null)}
              className="block w-full text-sm text-slate-600 file:mr-3 file:rounded-lg file:border-0 file:bg-accent file:px-3 file:py-2 file:text-sm file:text-white dark:text-slate-300 dark:file:bg-accent-dark dark:file:text-slate-900"
            />
            <label className="block space-y-1">
              <span className="text-xs font-medium text-slate-500">
                Restore as (optional — leave blank to use the original name)
              </span>
              <input
                value={targetId}
                onChange={(e) => setTargetId(e.target.value)}
                placeholder="new-stack-name"
                className="w-full rounded-lg border border-slate-300 bg-white px-3 py-2 text-sm dark:border-slate-600 dark:bg-slate-800"
              />
            </label>
            <Checkbox
              checked={restoreVolumes}
              onChange={setRestoreVolumes}
              label="Restore volume data"
            />
            <Checkbox
              checked={overwrite}
              onChange={setOverwrite}
              label="Overwrite if a stack with this id already exists"
              hint="Replaces the existing stack files and volume contents."
            />
          </div>
          <div className="mt-4 flex justify-end gap-2">
            <Button variant="outline" onClick={() => setOpen(false)} disabled={busy}>
              Cancel
            </Button>
            <Button onClick={run} loading={busy} disabled={!file}>
              Restore
            </Button>
          </div>
        </Modal>
      )}
    </>
  );
}