// components/utilities/files/FileBrowserPanel.tsx
"use client";

import { useCallback, useEffect, useMemo, useState } from "react";
import { ChevronRight, Home, Loader2 } from "lucide-react";
import FilesTable from "./FilesTable";
import FilePreview from "./FilePreview";
import { FsEntry, list, parentDir, download, SortDir, SortKey } from "./api";

export default function FileBrowserPanel() {
    const [cwd, setCwd] = useState<string>("/");
    const [entries, setEntries] = useState<FsEntry[]>([]);
    const [loading, setLoading] = useState<boolean>(true);
    const [error, setError] = useState<string | null>(null);

    const [selected, setSelected] = useState<FsEntry | null>(null);

    const [sortKey, setSortKey] = useState<SortKey>("name");
    const [sortDir, setSortDir] = useState<SortDir>("asc");

    const refresh = useCallback(async (path: string) => {
        setLoading(true);
        setError(null);
        try {
            const res = await list(path);
            setCwd(res.cwd || path || "/");
            setEntries(res.entries || []);
            // Clear selection if it no longer exists
            if (selected && !res.entries.find(e => e.path === selected.path)) setSelected(null);
        } catch (e: any) {
            setError(e?.message || String(e));
        } finally {
            setLoading(false);
        }
    }, [selected]);

    useEffect(() => { refresh(cwd); /* eslint-disable-next-line react-hooks/exhaustive-deps */ }, []);

    const crumbs = useMemo(() => {
        const norm = cwd.replace(/\\/g, "/");
        const segs = norm.split("/").filter(Boolean);
        const out: { label: string; path: string }[] = [{ label: "root", path: "/" }];
        let acc = "";
        for (const s of segs) {
            acc += "/" + s;
            out.push({ label: s, path: acc || "/" });
        }
        return out;
    }, [cwd]);

    function openEntry(e: FsEntry) {
        if (e.isDir) {
            setSelected(null);
            refresh(e.path);
        } else {
            setSelected(e);
        }
    }

    function onSort(k: SortKey) {
        if (k === sortKey) {
            setSortDir(d => (d === "asc" ? "desc" : "asc"));
        } else {
            setSortKey(k);
            setSortDir("asc");
        }
    }

    async function goUp() {
        const p = parentDir(cwd);
        setSelected(null);
        await refresh(p);
    }

    return (
        <div className="space-y-4">
        {/* Top bar */}
        <div className="flex flex-wrap items-center gap-2">
        {/* Breadcrumbs */}
        <nav className="flex items-center gap-1 text-sm">
        {crumbs.map((c, i) => (
            <span key={c.path} className="inline-flex items-center">
            {i === 0 ? (
                <button
                className="inline-flex items-center gap-1 rounded-md border px-2 py-0.5 hover:bg-muted"
                onClick={() => { setSelected(null); refresh("/"); }}
                title="Go to root"
                >
                <Home className="w-3.5 h-3.5" />
                root
                </button>
            ) : (
                <button
                className="rounded-md border px-2 py-0.5 hover:bg-muted"
                onClick={() => { setSelected(null); refresh(c.path); }}
                title={c.path}
                >
                {c.label}
                </button>
            )}
            {i < crumbs.length - 1 && <ChevronRight className="w-3.5 h-3.5 mx-1 opacity-60" />}
            </span>
        ))}
        </nav>

        <div className="ml-auto flex items-center gap-2">
        <button
        onClick={() => refresh(cwd)}
        className="rounded-md border px-2 py-1 text-sm hover:bg-muted inline-flex items-center gap-2"
        title="Refresh"
        disabled={loading}
        >
        {loading && <Loader2 className="w-4 h-4 animate-spin" />}
        Refresh
        </button>
        <button
        onClick={goUp}
        className="rounded-md border px-2 py-1 text-sm hover:bg-muted"
        title="Up one level"
        disabled={cwd === "/"}
        >
        Up
        </button>
        </div>
        </div>

        {/* Error */}
        {error && (
            <div className="rounded-md border border-rose-600/40 bg-rose-600/10 p-3 text-sm">
            {error}
            </div>
        )}

        {/* Two-column layout */}
        <div className="grid grid-cols-1 lg:grid-cols-3 gap-4">
        <div className="lg:col-span-2">
        {loading ? (
            <div className="rounded-md border p-6 text-sm text-zinc-400 flex items-center gap-2">
            <Loader2 className="w-4 h-4 animate-spin" /> Loading…
            </div>
        ) : (
            <FilesTable
            entries={entries}
            sortKey={sortKey}
            sortDir={sortDir}
            onSort={onSort}
            onOpen={openEntry}
            onDownload={(e) => download(e.path)}
            />
        )}
        </div>

        <div className="lg:col-span-1">
        <div className="rounded-md border p-3">
        <div className="text-sm text-zinc-400 mb-2">Preview</div>
        {selected ? (
            <FilePreview path={selected.path} mime={selected.mime} name={selected.name} />
        ) : (
            <div className="text-sm text-zinc-500">Select a file to preview.</div>
        )}
        </div>
        </div>
        </div>
        </div>
    );
}