import { useState, useEffect, useRef } from "react";
import {
  Upload,
  Trash2,
  FileText,
  FileSpreadsheet,
  File,
  Check,
  Loader2,
  Database,
  X,
  ChevronLeft,
  Link,
  Table,
} from "lucide-react";
import { toast } from "sonner";
import {
  getDocuments,
  uploadDocument,
  processDocument,
  deleteDocument,
  getDocumentTypes,
  getDatabaseClientTypes,
  connectDatabase,
  getDatabaseClients,
  deleteDatabaseClient,
  ingestDatabaseClient,
  getDataCatalog,
  type ApiDocument,
  type DocumentStatus,
  type DocTypeInfo,
  type DbType,
  type DbTypeInfo,
  type DatabaseClient,
  type DataCatalogSource,
} from "../../services/api";

interface KnowledgeManagementProps {
  open: boolean;
  onClose: () => void;
}

type View = "main" | "db-select" | "db-credentials" | "catalog";

const LOGO_MAP: Record<string, string> = {
  postgres:  "https://cdn.simpleicons.org/postgresql/336791",
  mysql:     "https://cdn.simpleicons.org/mysql/4479A1",
  supabase:  "https://cdn.simpleicons.org/supabase/3ECF8E",
  sqlserver: "https://cdn.jsdelivr.net/gh/devicons/devicon@latest/icons/microsoftsqlserver/microsoftsqlserver-plain.svg",
  bigquery:  "https://cdn.simpleicons.org/googlebigquery/4285F4",
  snowflake: "https://cdn.simpleicons.org/snowflake/29B5E8",
};

const getUserId = (): string | null => {
  const stored = localStorage.getItem("chatbot_user");
  if (!stored) return null;
  return (JSON.parse(stored).user_id as string) ?? null;
};

const FILE_ICON_MAP: Record<string, { icon: React.ElementType; bg: string; color: string }> = {
  pdf:  { icon: FileText,        bg: "bg-red-50",    color: "text-red-400"    },
  docx: { icon: FileText,        bg: "bg-blue-50",   color: "text-blue-400"   },
  txt:  { icon: File,            bg: "bg-slate-100", color: "text-slate-400"  },
  csv:  { icon: FileSpreadsheet, bg: "bg-green-50",  color: "text-green-500"  },
  xlsx: { icon: FileSpreadsheet, bg: "bg-emerald-50",color: "text-emerald-500"},
};

const getFileIcon = (fileType: string) =>
  FILE_ICON_MAP[fileType.toLowerCase()] ?? { icon: File, bg: "bg-slate-100", color: "text-slate-400" };

export default function KnowledgeManagement({
  open,
  onClose,
}: KnowledgeManagementProps) {
  // ── Document state ──────────────────────────────────────────────────────────
  const [docTypes, setDocTypes] = useState<DocTypeInfo[]>([]);
  const [documents, setDocuments] = useState<ApiDocument[]>([]);
  const [loadingDocs, setLoadingDocs] = useState(false);
  const [docsError, setDocsError] = useState<string | null>(null);
  const [uploading, setUploading] = useState(false);
  const [uploadProgress, setUploadProgress] = useState<number>(0);
  const [uploadError, setUploadError] = useState<string | null>(null);
  const [processing, setProcessing] = useState<string | null>(null);
  const [deleting, setDeleting] = useState<string | null>(null);

  // ── Navigation state ────────────────────────────────────────────────────────
  const [view, setView] = useState<View>("main");
  const [selectedDbType, setSelectedDbType] = useState<DbType | null>(null);

  // ── DB type & client state ──────────────────────────────────────────────────
  const [dbTypeInfos, setDbTypeInfos] = useState<DbTypeInfo[]>([]);
  const [dbClients, setDbClients] = useState<DatabaseClient[]>([]);
  const [loadingDbTypes, setLoadingDbTypes] = useState(false);
  const [ingesting, setIngesting] = useState<string | null>(null);
  const [deletingClient, setDeletingClient] = useState<string | null>(null);
  const pollingTimers = useRef<Map<string, ReturnType<typeof setInterval>>>(new Map());

  // ── Data Catalog state ──────────────────────────────────────────────────────
  const [catalogSources, setCatalogSources] = useState<DataCatalogSource[]>([]);
  const [loadingCatalog, setLoadingCatalog] = useState(false);

  // ── DB credentials form state ───────────────────────────────────────────────
  const [connectionName, setConnectionName] = useState("");
  const [dbForm, setDbForm] = useState<Record<string, string | number | boolean>>({});
  const [connecting, setConnecting] = useState(false);

  useEffect(() => {
    return () => {
      pollingTimers.current.forEach((timer) => clearInterval(timer));
      pollingTimers.current.clear();
    };
  }, []);

  const startPollingDocument = (userId: string, docId: string) => {
    if (pollingTimers.current.has(docId)) return;
    const timer = setInterval(async () => {
      try {
        const docs = await getDocuments(userId);
        const updated = docs.find((d) => d.id === docId);
        if (updated && (updated.status === "completed" || updated.status === "failed")) {
          clearInterval(timer);
          pollingTimers.current.delete(docId);
          setDocuments((prev) =>
            prev.map((d) => (d.id === docId ? { ...d, status: updated.status } : d))
          );
        }
      } catch {
        // ignore transient errors, keep polling
      }
    }, 3000);
    pollingTimers.current.set(docId, timer);
  };

  useEffect(() => {
    if (!open) return;
    const userId = getUserId();
    if (!userId) return;
    loadDocuments(userId);
    loadDbData(userId);
    getDocumentTypes()
      .then((types) => setDocTypes(types.filter((t) => t.status === "active")))
      .catch(() =>
        setDocTypes([
          { type: "pdf",  max_size_mb: 10, status: "active", message: null },
          { type: "csv",  max_size_mb: 10, status: "active", message: null },
          { type: "xlsx", max_size_mb: 10, status: "active", message: null },
        ])
      );
  }, [open]);

  const acceptedExtensions = docTypes.map((t) => `.${t.type}`).join(",");
  const supportedFormatsText = docTypes.map((t) => t.type.toUpperCase()).join(", ");

  const loadDbData = async (userId: string) => {
    setLoadingDbTypes(true);
    try {
      const [types, clients] = await Promise.all([
        getDatabaseClientTypes(),
        getDatabaseClients(userId),
      ]);
      setDbTypeInfos(types);
      setDbClients(clients);
    } catch {
      // non-blocking; silently fail
    } finally {
      setLoadingDbTypes(false);
    }
  };

  const handleClose = () => {
    setView("main");
    setSelectedDbType(null);
    setConnectionName("");
    setDbForm({});
    onClose();
  };

  // ── Document handlers ───────────────────────────────────────────────────────

  const loadDocuments = async (userId: string) => {
    setLoadingDocs(true);
    setDocsError(null);
    try {
      setDocuments(await getDocuments(userId));
    } catch (err) {
      setDocsError(
        err instanceof Error ? err.message : "Failed to load documents"
      );
    } finally {
      setLoadingDocs(false);
    }
  };

  const handleFileUpload = async (e: React.ChangeEvent<HTMLInputElement>) => {
    const files = e.target.files;
    if (!files || files.length === 0) return;
    const userId = getUserId();
    if (!userId) return;

    setUploading(true);
    setUploadProgress(0);
    setUploadError(null);

    for (let i = 0; i < files.length; i++) {
      const file = files[i];
      console.log(`[upload] ── file selected: "${file.name}", ${(file.size / 1024).toFixed(1)} KB`);
      const tClick = performance.now();
      try {
        console.log(`[upload] ── calling uploadDocument (pre-fetch delay: ${(performance.now() - tClick).toFixed(0)} ms)`);
        const uploadRes = await uploadDocument(userId, file, setUploadProgress);
        console.log(`[upload] ── uploadDocument returned, updating UI`);
        const newDoc: ApiDocument = {
          ...uploadRes.data,
          id: uploadRes.data.id,
        };
        setDocuments((prev) => [newDoc, ...prev]);
        console.log(`[upload] ── done in ${(performance.now() - tClick).toFixed(0)} ms total`);
      } catch (err) {
        console.error(`[upload] ✗ failed after ${(performance.now() - tClick).toFixed(0)} ms:`, err);
        setUploadError(err instanceof Error ? err.message : "Upload failed");
      }
    }

    setUploading(false);
    e.target.value = "";
  };

  const processDocumentById = async (userId: string, docId: string) => {
    setProcessing(docId);
    setDocuments((prev) =>
      prev.map((d) =>
        d.id === docId ? { ...d, status: "processing" as DocumentStatus } : d
      )
    );
    const tProcess = performance.now();
    try {
      console.log(`[process] ── calling processDocument for doc: ${docId}`);
      await processDocument(userId, docId);
      console.log(`[process] ── accepted in ${(performance.now() - tProcess).toFixed(0)} ms, polling started`);
      startPollingDocument(userId, docId);
    } catch {
      setDocuments((prev) =>
        prev.map((d) =>
          d.id === docId ? { ...d, status: "failed" as DocumentStatus } : d
        )
      );
    } finally {
      setProcessing(null);
    }
  };

  const handleDeleteDocument = async (docId: string) => {
    const userId = getUserId();
    if (!userId) return;
    setDeleting(docId);
    try {
      await deleteDocument(userId, docId);
      setDocuments((prev) => prev.filter((d) => d.id !== docId));
    } catch (err) {
      console.error("Delete failed:", err);
    } finally {
      setDeleting(null);
    }
  };

  const deleteAllDocuments = async () => {
    if (!window.confirm("Are you sure you want to delete all documents?"))
      return;
    const userId = getUserId();
    if (!userId) return;
    for (const doc of documents) {
      try {
        await deleteDocument(userId, doc.id);
      } catch {
        // continue deleting others
      }
    }
    setDocuments([]);
  };

  // ── DB handlers ─────────────────────────────────────────────────────────────

  const handleDbConnect = async () => {
    const userId = getUserId();
    if (!userId || !selectedDbType || !connectionName.trim()) return;
    setConnecting(true);
    try {
      await connectDatabase(userId, selectedDbType, connectionName.trim(), dbForm);
      const clients = await getDatabaseClients(userId);
      setDbClients(clients);
      toast.success("Database connected successfully");
      setView("main");
      setConnectionName("");
      setDbForm({});
    } catch (err) {
      toast.error(
        err instanceof Error ? err.message : "Failed to connect to database"
      );
    } finally {
      setConnecting(false);
    }
  };

  const handleIngest = async (clientId: string) => {
    const userId = getUserId();
    if (!userId) return;
    setIngesting(clientId);
    try {
      const res = await ingestDatabaseClient(clientId, userId);
      toast.success(`Ingested ${res.chunks_ingested} chunks successfully`);
    } catch (err) {
      toast.error(err instanceof Error ? err.message : "Ingestion failed");
    } finally {
      setIngesting(null);
    }
  };

  const handleDeleteClient = async (clientId: string) => {
    const userId = getUserId();
    if (!userId) return;
    setDeletingClient(clientId);
    try {
      await deleteDatabaseClient(clientId, userId);
      setDbClients((prev) => prev.filter((c) => c.id !== clientId));
    } catch (err) {
      toast.error(err instanceof Error ? err.message : "Failed to delete connection");
    } finally {
      setDeletingClient(null);
    }
  };

  // ── Helpers ─────────────────────────────────────────────────────────────────

  const formatFileSize = (bytes: number) => {
    if (bytes < 1024) return bytes + " B";
    if (bytes < 1024 * 1024) return (bytes / 1024).toFixed(2) + " KB";
    return (bytes / (1024 * 1024)).toFixed(2) + " MB";
  };

  const formatDate = (isoString: string) => {
    return new Date(isoString).toLocaleString();
  };

  const renderStatus = (doc: ApiDocument) => {
    if (doc.status === "completed") {
      return (
        <div className="flex items-center gap-1.5 text-green-600">
          <Check className="w-3.5 h-3.5" />
          <span className="text-xs font-medium">Processed</span>
        </div>
      );
    }

    if (doc.status === "processing" || processing === doc.id) {
      return (
        <div className="flex items-center gap-1.5 text-blue-600">
          <Loader2 className="w-3.5 h-3.5 animate-spin" />
          <span className="text-xs">Processing...</span>
        </div>
      );
    }

    return (
      <button
        onClick={() => {
          const userId = getUserId();
          if (userId) processDocumentById(userId, doc.id);
        }}
        disabled={processing === doc.id}
        className="flex items-center gap-1.5 bg-gradient-to-r from-[#00C853] to-[#00A843] text-white px-3 py-1.5 rounded-lg hover:from-[#00A843] hover:to-[#00962B] transition disabled:opacity-50 disabled:cursor-not-allowed text-xs"
      >
        <Database className="w-3.5 h-3.5" />
        {doc.status === "failed" ? "Retry Process" : "Process to Knowledge"}
      </button>
    );
  };

  const handleViewCatalog = async () => {
    const uid = getUserId();
    setLoadingCatalog(true);
    setView("catalog");
    try {
      if (!uid) throw new Error("no user");
      const catalog = await getDataCatalog(uid);
      setCatalogSources(catalog.sources.filter((s) => s.source_type !== "unstructured"));
    } catch {
      setCatalogSources([]);
    } finally {
      setLoadingCatalog(false);
    }
  };

  if (!open) return null;

  // ── Header title & back button logic ────────────────────────────────────────

  const selectedDbInfo = dbTypeInfos.find((d) => d.db_type === selectedDbType);

  const headerTitle =
    view === "db-select"
      ? "Connect Database"
      : view === "db-credentials"
      ? `Connect to ${selectedDbInfo?.display_name ?? selectedDbType}`
      : view === "catalog"
      ? "Data Catalog"
      : "Knowledge Base";

  const headerBack =
    view === "db-select"
      ? () => setView("main")
      : view === "db-credentials"
      ? () => setView("db-select")
      : view === "catalog"
      ? () => setView("main")
      : null;

  // ── Render ───────────────────────────────────────────────────────────────────

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/40 backdrop-blur-sm p-4">
      <div className="bg-white rounded-2xl shadow-xl w-full max-w-md max-h-[85vh] flex flex-col">

        {/* Header */}
        <div className="flex items-center justify-between px-5 py-4 border-b border-slate-100">
          <div className="flex items-center gap-3">
            {headerBack ? (
              <button
                onClick={headerBack}
                className="p-1.5 -ml-1 rounded-lg text-slate-400 hover:text-slate-700 hover:bg-slate-100 transition"
                aria-label="Back"
              >
                <ChevronLeft className="w-4 h-4" />
              </button>
            ) : (
              <div className="w-7 h-7 rounded-lg bg-orange-100 flex items-center justify-center">
                <Database className="w-4 h-4 text-[#FF8F00]" />
              </div>
            )}
            <h2 className="text-sm font-semibold text-slate-900">{headerTitle}</h2>
          </div>
          <div className="flex items-center gap-1">
            {view === "main" && (
              <button
                onClick={handleViewCatalog}
                title="View data catalog"
                className="p-1.5 rounded-lg text-slate-400 hover:text-[#FF8F00] hover:bg-orange-50 transition"
              >
                <Table className="w-4 h-4" />
              </button>
            )}
            <button
              onClick={handleClose}
              className="p-1.5 rounded-lg text-slate-400 hover:text-slate-700 hover:bg-slate-100 transition"
            >
              <X className="w-4 h-4" />
            </button>
          </div>
        </div>

        {/* Content */}
        <div className="flex-1 overflow-y-auto px-5 py-4">

          {/* ── VIEW: main ── */}
          {view === "main" && (
            <div className="space-y-4">

              {/* Upload zone */}
              <label
                htmlFor="file-upload"
                className="group flex flex-col items-center gap-2.5 border-2 border-dashed border-slate-200 rounded-xl p-7 cursor-pointer hover:border-[#FF8F00] hover:bg-orange-50/30 transition-colors"
              >
                <div className="w-10 h-10 rounded-xl bg-slate-100 group-hover:bg-orange-100 flex items-center justify-center transition-colors">
                  {uploading ? (
                    <Loader2 className="w-5 h-5 text-[#FF8F00] animate-spin" />
                  ) : (
                    <Upload className="w-5 h-5 text-slate-400 group-hover:text-[#FF8F00] transition-colors" />
                  )}
                </div>
                <div className="text-center">
                  <p className="text-sm font-medium text-slate-700">
                    {uploading ? `Uploading… ${uploadProgress}%` : (
                      <>Drop files, or <span className="text-[#FF8F00]">browse</span></>
                    )}
                  </p>
                  {uploading && (
                    <div className="w-32 h-1.5 bg-slate-200 rounded-full overflow-hidden mt-1.5 mx-auto">
                      <div
                        className="h-full bg-[#FF8F00] transition-all duration-300"
                        style={{ width: `${uploadProgress}%` }}
                      />
                    </div>
                  )}
                  {!uploading && <p className="text-xs text-slate-400 mt-0.5">{supportedFormatsText}</p>}
                </div>
                <input
                  id="file-upload"
                  type="file"
                  accept={acceptedExtensions}
                  multiple
                  onChange={handleFileUpload}
                  className="hidden"
                  disabled={uploading}
                />
              </label>

              {uploadError && (
                <p className="text-xs text-red-500 bg-red-50 border border-red-100 px-3 py-2 rounded-lg">
                  {uploadError}
                </p>
              )}

              {/* Connect DB row */}
              <button
                onClick={() => setView("db-select")}
                className="w-full flex items-center gap-3 px-4 py-3 rounded-xl border border-slate-200 hover:border-slate-300 hover:bg-slate-50 transition text-left group"
              >
                <div className="w-8 h-8 rounded-lg bg-slate-100 group-hover:bg-slate-200 flex items-center justify-center flex-shrink-0 transition-colors">
                  <Link className="w-4 h-4 text-slate-500" />
                </div>
                <div className="flex-1 min-w-0">
                  <p className="text-sm font-medium text-slate-700">Connect a Database</p>
                  <p className="text-xs text-slate-400">PostgreSQL and more</p>
                </div>
                <ChevronLeft className="w-4 h-4 text-slate-300 rotate-180 flex-shrink-0" />
              </button>

              {/* Database connections list */}
              {dbClients.length > 0 && (
                <div>
                  <div className="flex items-center justify-between mb-2">
                    <span className="text-[11px] font-semibold text-slate-400 uppercase tracking-wider">
                      Databases · {dbClients.length}
                    </span>
                  </div>
                  <div className="space-y-1">
                    {dbClients.map((client) => (
                      <div
                        key={client.id}
                        className="flex items-center gap-3 px-3 py-2.5 rounded-xl hover:bg-slate-50 transition group"
                      >
                        <div className="w-8 h-8 rounded-lg bg-slate-100 flex items-center justify-center flex-shrink-0">
                          <img
                            src={LOGO_MAP[client.db_type] ?? ""}
                            alt={client.db_type}
                            className="w-5 h-5 object-contain"
                          />
                        </div>
                        <div className="flex-1 min-w-0">
                          <p className="text-sm font-medium text-slate-800 truncate">{client.name}</p>
                          <p className="text-xs text-slate-400 capitalize">{client.db_type} · {client.status}</p>
                        </div>
                        <div className="flex items-center gap-1.5 flex-shrink-0">
                          <button
                            onClick={() => handleIngest(client.id)}
                            disabled={ingesting === client.id || client.status === "inactive"}
                            title="Ingest schema to knowledge base"
                            className="flex items-center gap-1 text-xs px-2.5 py-1 rounded-lg bg-slate-100 hover:bg-orange-100 hover:text-[#FF8F00] text-slate-500 transition disabled:opacity-40 disabled:cursor-not-allowed"
                          >
                            {ingesting === client.id ? (
                              <Loader2 className="w-3 h-3 animate-spin" />
                            ) : (
                              <Database className="w-3 h-3" />
                            )}
                            {ingesting === client.id ? "Ingesting…" : "Ingest"}
                          </button>
                          <button
                            onClick={() => handleDeleteClient(client.id)}
                            disabled={deletingClient === client.id}
                            className="opacity-0 group-hover:opacity-100 text-slate-300 hover:text-red-500 transition disabled:opacity-30"
                            title="Delete connection"
                          >
                            {deletingClient === client.id ? (
                              <Loader2 className="w-3.5 h-3.5 animate-spin" />
                            ) : (
                              <Trash2 className="w-3.5 h-3.5" />
                            )}
                          </button>
                        </div>
                      </div>
                    ))}
                  </div>
                </div>
              )}

              {/* Documents list */}
              <div>
                <div className="flex items-center justify-between mb-2">
                  <span className="text-[11px] font-semibold text-slate-400 uppercase tracking-wider">
                    Documents · {documents.length}
                  </span>
                  {documents.length > 0 && (
                    <button
                      onClick={deleteAllDocuments}
                      className="text-xs text-slate-400 hover:text-red-500 flex items-center gap-1 transition"
                    >
                      <Trash2 className="w-3 h-3" />
                      Clear all
                    </button>
                  )}
                </div>

                {loadingDocs ? (
                  <div className="flex justify-center py-10">
                    <Loader2 className="w-5 h-5 animate-spin text-slate-300" />
                  </div>
                ) : docsError ? (
                  <p className="text-center text-xs text-red-500 py-6">{docsError}</p>
                ) : documents.length === 0 ? (
                  <div className="text-center py-10">
                    <div className="w-12 h-12 rounded-2xl bg-slate-100 flex items-center justify-center mx-auto mb-3">
                      <FileText className="w-5 h-5 text-slate-300" />
                    </div>
                    <p className="text-sm text-slate-400">No documents yet</p>
                    <p className="text-xs text-slate-300 mt-0.5">Upload files to get started</p>
                  </div>
                ) : (
                  <div className="space-y-1">
                    {documents.map((doc) => (
                      <div
                        key={doc.id}
                        className="flex items-center gap-3 px-3 py-2.5 rounded-xl hover:bg-slate-50 transition group"
                      >
                        <div className={`w-8 h-8 rounded-lg ${getFileIcon(doc.file_type).bg} flex items-center justify-center flex-shrink-0`}>
                          {(() => { const { icon: Icon, color } = getFileIcon(doc.file_type); return <Icon className={`w-4 h-4 ${color}`} />; })()}
                        </div>
                        <div className="flex-1 min-w-0">
                          <p className="text-sm font-medium text-slate-800 truncate" title={doc.filename}>
                            {doc.filename}
                          </p>
                          <p className="text-xs text-slate-400">
                            {formatFileSize(doc.file_size)} · {formatDate(doc.created_at)}
                          </p>
                        </div>
                        <div className="flex items-center gap-2 flex-shrink-0">
                          {renderStatus(doc)}
                          <button
                            onClick={() => handleDeleteDocument(doc.id)}
                            disabled={deleting === doc.id}
                            className="opacity-0 group-hover:opacity-100 text-slate-300 hover:text-red-500 transition disabled:opacity-30"
                            title="Delete"
                          >
                            {deleting === doc.id ? (
                              <Loader2 className="w-3.5 h-3.5 animate-spin" />
                            ) : (
                              <Trash2 className="w-3.5 h-3.5" />
                            )}
                          </button>
                        </div>
                      </div>
                    ))}
                  </div>
                )}
              </div>
            </div>
          )}

          {/* ── VIEW: db-select ── */}
          {view === "db-select" && (
            <div className="space-y-4">
              <p className="text-sm text-slate-400">
                Choose a database to connect to your knowledge base.
              </p>
              {loadingDbTypes ? (
                <div className="flex justify-center py-10">
                  <Loader2 className="w-5 h-5 animate-spin text-slate-300" />
                </div>
              ) : (
                <div className="grid grid-cols-3 gap-2">
                  {dbTypeInfos.map((info) => {
                    const active = info.status === "active";
                    return (
                      <button
                        key={info.db_type}
                        disabled={!active}
                        onClick={() => {
                          if (!active) return;
                          setSelectedDbType(info.db_type);
                          const defaults = Object.fromEntries(
                            info.fields.map((f) => [
                              f.name,
                              f.default != null
                                ? f.default
                                : f.type === "integer" ? 0 : f.type === "boolean" ? false : "",
                            ])
                          );
                          setDbForm(defaults);
                          setView("db-credentials");
                        }}
                        className={[
                          "relative flex flex-col items-center gap-2 p-4 rounded-xl border transition text-xs font-medium",
                          active
                            ? "border-slate-200 hover:border-[#FF8F00] hover:bg-orange-50/50 text-slate-700 cursor-pointer"
                            : "border-slate-100 bg-slate-50/60 text-slate-400 cursor-not-allowed",
                        ].join(" ")}
                      >
                        <img
                          src={LOGO_MAP[info.logo] ?? ""}
                          alt={info.display_name}
                          className={`w-8 h-8 object-contain ${!active ? "opacity-30 grayscale" : ""}`}
                        />
                        <span>{info.display_name}</span>
                        {!active && (
                          <span className="absolute top-1.5 right-1.5 text-[9px] bg-slate-200 text-slate-400 px-1.5 py-0.5 rounded-full">
                            Soon
                          </span>
                        )}
                      </button>
                    );
                  })}
                </div>
              )}
            </div>
          )}

          {/* ── VIEW: db-credentials ── */}
          {view === "db-credentials" && (
            <div className="space-y-4">

              {/* Selected DB chip */}
              {selectedDbInfo && (
                <div className="flex items-center gap-2.5 px-3 py-2.5 rounded-xl bg-slate-50 border border-slate-100">
                  <img src={LOGO_MAP[selectedDbInfo.logo] ?? ""} alt={selectedDbInfo.display_name} className="w-5 h-5 object-contain" />
                  <span className="text-sm font-medium text-slate-700">{selectedDbInfo.display_name}</span>
                </div>
              )}

              <div className="grid grid-cols-2 gap-3">
                {/* Connection Name */}
                <div className="col-span-2">
                  <label className="block text-xs font-medium text-slate-500 mb-1">
                    Connection Name <span className="text-red-400">*</span>
                  </label>
                  <input
                    type="text"
                    placeholder="Production DB"
                    value={connectionName}
                    onChange={(e) => setConnectionName(e.target.value)}
                    className="w-full border border-slate-200 rounded-lg px-3 py-2 text-sm bg-white focus:outline-none focus:ring-2 focus:ring-[#FF8F00]/25 focus:border-[#FF8F00] placeholder:text-slate-300 transition"
                  />
                </div>

                {/* Dynamic fields from API */}
                {selectedDbInfo?.fields.map((field) => (
                  <div
                    key={field.name}
                    className={field.name === "host" || field.name === "service_account_json" ? "col-span-2" : ""}
                  >
                    <label className="block text-xs font-medium text-slate-500 mb-1 capitalize">
                      {field.name.replace(/_/g, " ")}
                      {field.required && <span className="text-red-400 ml-0.5">*</span>}
                    </label>

                    {field.type === "select" ? (
                      <select
                        value={String(dbForm[field.name] ?? field.default ?? "")}
                        onChange={(e) => setDbForm((f) => ({ ...f, [field.name]: e.target.value }))}
                        className="w-full border border-slate-200 rounded-lg px-3 py-2 text-sm bg-white focus:outline-none focus:ring-2 focus:ring-[#FF8F00]/25 focus:border-[#FF8F00] transition"
                      >
                        {field.options?.map((opt) => (
                          <option key={opt} value={opt}>{opt}</option>
                        ))}
                      </select>
                    ) : field.type === "boolean" ? (
                      <div className="flex items-center gap-2 pt-1">
                        <input
                          type="checkbox"
                          id={`field-${field.name}`}
                          checked={Boolean(dbForm[field.name] ?? field.default ?? false)}
                          onChange={(e) => setDbForm((f) => ({ ...f, [field.name]: e.target.checked }))}
                          className="w-4 h-4 accent-[#FF8F00]"
                        />
                        <label htmlFor={`field-${field.name}`} className="text-xs text-slate-500">
                          {field.description}
                        </label>
                      </div>
                    ) : field.name === "service_account_json" ? (
                      <textarea
                        rows={4}
                        placeholder={field.description}
                        value={String(dbForm[field.name] ?? "")}
                        onChange={(e) => setDbForm((f) => ({ ...f, [field.name]: e.target.value }))}
                        className="w-full border border-slate-200 rounded-lg px-3 py-2 text-xs bg-white focus:outline-none focus:ring-2 focus:ring-[#FF8F00]/25 focus:border-[#FF8F00] placeholder:text-slate-300 transition font-mono"
                      />
                    ) : (
                      <input
                        type={field.sensitive ? "password" : field.type === "integer" ? "number" : "text"}
                        placeholder={field.default != null ? String(field.default) : field.description}
                        value={String(dbForm[field.name] ?? "")}
                        onChange={(e) =>
                          setDbForm((f) => ({
                            ...f,
                            [field.name]: field.type === "integer"
                              ? (parseInt(e.target.value, 10) || 0)
                              : e.target.value,
                          }))
                        }
                        className="w-full border border-slate-200 rounded-lg px-3 py-2 text-sm bg-white focus:outline-none focus:ring-2 focus:ring-[#FF8F00]/25 focus:border-[#FF8F00] placeholder:text-slate-300 transition"
                      />
                    )}
                  </div>
                ))}
              </div>

              <button
                onClick={handleDbConnect}
                disabled={
                  connecting ||
                  !connectionName.trim() ||
                  (selectedDbInfo?.fields.filter((f) => f.required).some((f) => !dbForm[f.name]) ?? false)
                }
                className="w-full flex items-center justify-center gap-2 bg-[#FF8F00] hover:bg-[#FF6F00] active:bg-[#E65100] text-white py-2.5 rounded-xl text-sm font-medium transition disabled:opacity-40 disabled:cursor-not-allowed"
              >
                {connecting ? (
                  <><Loader2 className="w-4 h-4 animate-spin" /> Connecting…</>
                ) : (
                  "Connect"
                )}
              </button>
            </div>
          )}

          {/* ── VIEW: catalog ── */}
          {view === "catalog" && (
            <div className="space-y-2">
              {loadingCatalog ? (
                <div className="flex justify-center py-10">
                  <Loader2 className="w-5 h-5 animate-spin text-slate-300" />
                </div>
              ) : catalogSources.length === 0 ? (
                <p className="text-center text-xs text-slate-400 py-8">No structured data indexed yet.</p>
              ) : (
                catalogSources.map((src) => (
                  <div key={src.source_id} className="flex items-center gap-3 px-3 py-2.5 rounded-xl border border-slate-100">
                    <div className="w-8 h-8 rounded-lg bg-slate-100 flex items-center justify-center flex-shrink-0">
                      {src.source_type === "schema"
                        ? <Database className="w-4 h-4 text-slate-500" />
                        : <Table className="w-4 h-4 text-slate-500" />}
                    </div>
                    <div className="flex-1 min-w-0">
                      <p className="text-sm font-medium text-slate-800 truncate">{src.name}</p>
                      <p className="text-xs text-slate-400">
                        {src.source_type === "schema" ? "Database" : "Tabular"}
                        {src.table_count != null ? ` · ${src.table_count} table${src.table_count !== 1 ? "s" : ""}` : ""}
                      </p>
                    </div>
                  </div>
                ))
              )}
            </div>
          )}
        </div>

        {/* Footer */}
        <div className="px-5 py-3 border-t border-slate-100">
          <p className="text-[10px] text-slate-300 text-center">
            {view === "main"
              ? `Supported formats: ${supportedFormatsText}`
              : view === "db-select"
              ? "More integrations coming soon"
              : view === "catalog"
              ? "Structured data sources (database schemas & tabular files)"
              : "Credentials are encrypted at rest"}
          </p>
        </div>

      </div>
    </div>
  );
}