/**
 * DocumentsPanel — Shared documents tab for the meeting right rail.
 *
 * Features:
 *   - Upload files (txt/md/pdf)
 *   - Add URL links
 *   - List documents with type icons
 *   - Preview text files
 *   - Download files
 *   - Delete documents
 *
 * Additive — lives inside MeetingRightRail as a tab.
 */
import React, { useEffect, useMemo, useState, useRef } from 'react';
import { FileText, Link as LinkIcon, Upload, Trash2, Eye, Download, Plus, X, } from 'lucide-react';
import { useTeamsDocuments } from './useTeamsDocuments';
// ---------------------------------------------------------------------------
// Component
// ---------------------------------------------------------------------------
export function DocumentsPanel({ backendUrl, apiKey, roomId, initialDocuments, onDocumentsChanged, }) {
    const docsApi = useTeamsDocuments(backendUrl, apiKey);
    const [docs, setDocs] = useState(initialDocuments || []);
    const [selectedId, setSelectedId] = useState(null);
    const [previewText, setPreviewText] = useState('');
    const [busy, setBusy] = useState(false);
    const [showUrlForm, setShowUrlForm] = useState(false);
    const fileInputRef = useRef(null);
    const selected = useMemo(() => docs.find((d) => d.id === selectedId) || null, [docs, selectedId]);
    // Lazy refresh on mount
    useEffect(() => {
        ;
        (async () => {
            try {
                const list = await docsApi.list(roomId);
                setDocs(list);
                onDocumentsChanged?.(list);
            }
            catch {
                // keep local state
            }
        })();
        // eslint-disable-next-line react-hooks/exhaustive-deps
    }, [roomId]);
    const iconFor = (d) => {
        if (d.kind === 'url')
            return <LinkIcon size={12} className="text-blue-400/60"/>;
        const t = d.type;
        if (t === 'pdf')
            return <FileText size={12} className="text-red-400/60"/>;
        if (t === 'md')
            return <FileText size={12} className="text-purple-400/60"/>;
        return <FileText size={12} className="text-white/35"/>;
    };
    const sizeLabel = (bytes) => {
        if (typeof bytes !== 'number')
            return '';
        if (bytes < 1024)
            return `${bytes} B`;
        if (bytes < 1024 * 1024)
            return `${Math.round(bytes / 1024)} KB`;
        return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
    };
    async function handleUpload(file) {
        setBusy(true);
        try {
            const res = await docsApi.upload(roomId, file);
            const list = await docsApi.list(roomId);
            setDocs(list);
            onDocumentsChanged?.(list);
            setSelectedId(res.document.id);
        }
        catch (e) {
            console.error('Upload failed:', e);
        }
        finally {
            setBusy(false);
        }
    }
    async function handlePreview(docId) {
        setBusy(true);
        try {
            const text = await docsApi.preview(roomId, docId);
            setPreviewText(text);
            setSelectedId(docId);
        }
        catch (e) {
            console.error('Preview failed:', e);
            setPreviewText('[Failed to load preview]');
        }
        finally {
            setBusy(false);
        }
    }
    async function handleDelete(docId) {
        setBusy(true);
        try {
            await docsApi.deleteDoc(roomId, docId);
            const list = await docsApi.list(roomId);
            setDocs(list);
            onDocumentsChanged?.(list);
            if (selectedId === docId) {
                setSelectedId(null);
                setPreviewText('');
            }
        }
        catch (e) {
            console.error('Delete failed:', e);
        }
        finally {
            setBusy(false);
        }
    }
    async function handleDownload(doc) {
        setBusy(true);
        try {
            await docsApi.download(roomId, doc);
        }
        catch (e) {
            console.error('Download failed:', e);
        }
        finally {
            setBusy(false);
        }
    }
    return (<div className="h-full flex flex-col">
      {/* Actions row */}
      <div className="flex items-center gap-1.5 mb-2">
        <button onClick={() => fileInputRef.current?.click()} disabled={busy} className="flex items-center gap-1 px-2 py-1.5 rounded-lg bg-white/[0.04] border border-white/[0.08] text-[10px] text-white/50 hover:bg-white/[0.06] hover:text-white/70 transition-colors">
          <Upload size={11}/>
          Upload
        </button>
        <input ref={fileInputRef} type="file" className="hidden" onChange={(e) => {
            const f = e.target.files?.[0];
            if (f)
                handleUpload(f);
            e.currentTarget.value = '';
        }}/>
        <button onClick={() => setShowUrlForm(!showUrlForm)} disabled={busy} className={`flex items-center gap-1 px-2 py-1.5 rounded-lg border text-[10px] transition-colors ${showUrlForm
            ? 'bg-cyan-500/10 border-cyan-500/20 text-cyan-300'
            : 'bg-white/[0.04] border-white/[0.08] text-white/50 hover:bg-white/[0.06] hover:text-white/70'}`}>
          <LinkIcon size={11}/>
          Add Link
        </button>
      </div>

      {/* URL form */}
      {showUrlForm && (<AddUrlForm disabled={busy} onAdd={async (url, title) => {
                setBusy(true);
                try {
                    await docsApi.addUrl(roomId, url, title);
                    const list = await docsApi.list(roomId);
                    setDocs(list);
                    onDocumentsChanged?.(list);
                    setShowUrlForm(false);
                }
                catch (e) {
                    console.error('Add URL failed:', e);
                }
                finally {
                    setBusy(false);
                }
            }} onCancel={() => setShowUrlForm(false)}/>)}

      {/* Document list */}
      <div className="flex-1 min-h-0 overflow-y-auto space-y-1.5 scrollbar-hide">
        {docs.length === 0 && (<div className="text-center py-4">
            <FileText size={18} className="mx-auto text-white/10 mb-1.5"/>
            <p className="text-[10px] text-white/20">No shared documents yet</p>
            <p className="text-[9px] text-white/12 mt-0.5">Upload a file or add a link</p>
          </div>)}
        {docs.map((d) => (<div key={d.id} className={`rounded-lg border p-2.5 transition-colors ${selectedId === d.id
                ? 'bg-cyan-500/[0.06] border-cyan-500/15'
                : 'bg-white/[0.02] border-white/[0.04] hover:border-white/[0.08]'}`}>
            <div className="flex items-start gap-2">
              <div className="mt-0.5 flex-shrink-0">{iconFor(d)}</div>
              <div className="flex-1 min-w-0">
                <div className="text-[11px] text-white/65 font-medium truncate">{d.name}</div>
                <div className="text-[10px] text-white/25 mt-0.5">
                  {d.kind === 'url' ? 'Link' : (d.type || 'file').toUpperCase()}
                  {d.size_bytes ? ` · ${sizeLabel(d.size_bytes)}` : ''}
                  {d.uploaded_by ? ` · ${d.uploaded_by}` : ''}
                </div>
              </div>
            </div>
            {/* Action buttons */}
            <div className="flex items-center gap-1 mt-1.5">
              <button disabled={busy} onClick={() => handlePreview(d.id)} className="flex items-center gap-1 px-1.5 py-0.5 rounded text-[9px] text-white/35 hover:text-white/60 hover:bg-white/[0.04] transition-colors">
                <Eye size={9}/> Preview
              </button>
              {d.kind === 'file' && (<button disabled={busy} onClick={() => handleDownload(d)} className="flex items-center gap-1 px-1.5 py-0.5 rounded text-[9px] text-white/35 hover:text-white/60 hover:bg-white/[0.04] transition-colors">
                  <Download size={9}/> Download
                </button>)}
              <button disabled={busy} onClick={() => handleDelete(d.id)} className="flex items-center gap-1 px-1.5 py-0.5 rounded text-[9px] text-white/35 hover:text-red-300/70 hover:bg-red-500/[0.06] transition-colors ml-auto">
                <Trash2 size={9}/>
              </button>
            </div>
          </div>))}
      </div>

      {/* Preview pane */}
      {selected && previewText && (<div className="mt-2 rounded-lg border border-white/[0.06] bg-white/[0.02] p-2.5">
          <div className="flex items-center justify-between mb-1.5">
            <span className="text-[10px] text-white/40 font-medium truncate">{selected.name}</span>
            <div className="flex items-center gap-1">
              {selected.kind === 'file' && selected.type === 'pdf' && (<a href={`${backendUrl}/v1/teams/rooms/${roomId}/documents/${selected.id}/download`} target="_blank" rel="noopener noreferrer" className="px-1.5 py-0.5 rounded text-[9px] text-cyan-300/60 hover:text-cyan-200 hover:bg-cyan-500/10 transition-colors" title="Open PDF in new tab">
                  Open PDF
                </a>)}
              <button onClick={() => { setSelectedId(null); setPreviewText(''); }} className="p-0.5 rounded hover:bg-white/5 text-white/20 hover:text-white/40">
                <X size={10}/>
              </button>
            </div>
          </div>
          <pre className="text-[11px] leading-relaxed text-white/55 whitespace-pre-wrap max-h-48 overflow-y-auto scrollbar-hide font-mono">
            {previewText}
          </pre>
        </div>)}
    </div>);
}
// ---------------------------------------------------------------------------
// Sub-component: Add URL form
// ---------------------------------------------------------------------------
function AddUrlForm({ disabled, onAdd, onCancel, }) {
    const [url, setUrl] = useState('');
    const [title, setTitle] = useState('');
    return (<div className="rounded-lg border border-white/[0.06] bg-white/[0.02] p-2.5 mb-2 space-y-1.5">
      <input disabled={disabled} value={title} onChange={(e) => setTitle(e.target.value)} placeholder="Title (optional)" className="w-full px-2.5 py-1.5 rounded-lg bg-white/[0.04] border border-white/[0.06] text-[10px] text-white/70 placeholder:text-white/15 focus:outline-none focus:border-cyan-500/30"/>
      <div className="flex items-center gap-1.5">
        <input disabled={disabled} value={url} onChange={(e) => setUrl(e.target.value)} placeholder="https://..." className="flex-1 px-2.5 py-1.5 rounded-lg bg-white/[0.04] border border-white/[0.06] text-[10px] text-white/70 placeholder:text-white/15 focus:outline-none focus:border-cyan-500/30" onKeyDown={(e) => {
            if (e.key === 'Enter' && url.trim()) {
                onAdd(url.trim(), title.trim());
                setUrl('');
                setTitle('');
            }
        }}/>
        <button disabled={disabled || !url.trim()} onClick={() => {
            if (!url.trim())
                return;
            onAdd(url.trim(), title.trim());
            setUrl('');
            setTitle('');
        }} className={`px-2.5 py-1.5 rounded-lg text-[10px] font-medium border transition-colors ${url.trim() && !disabled
            ? 'bg-cyan-600/80 hover:bg-cyan-500 border-cyan-500/30 text-white'
            : 'bg-white/[0.04] border-white/[0.06] text-white/15'}`}>
          <Plus size={11}/>
        </button>
        <button onClick={onCancel} className="px-1.5 py-1.5 rounded-lg text-[10px] text-white/25 hover:text-white/45 hover:bg-white/[0.04] transition-colors">
          <X size={11}/>
        </button>
      </div>
    </div>);
}