feat(odin): left sidebar + lazy conversation creation (claude.ai-style)

- Replace top tabs with a left sidebar (New chat + scrollable conversation
  list, per-row rename/delete menu, active highlight), chat on the right.
- Fix duplicate-empty-conversations bug: "Nová konverzace" now just opens an
  empty composer; a DB row is created only on the first successful message
  (and a failed AI call no longer leaves an orphan conversation). Repeated
  clicks never spawn empties, and nothing empty survives a refresh.
- Land on a fresh new chat on mount; deleting the open conversation returns
  to new chat.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/admin/components/odin/OdinChat.tsx

@@ -17,7 +17,7 @@ import type {
   EditableField,
   StagedFile,
 } from "./types";
-import OdinTabs from "./OdinTabs";
+import OdinSidebar from "./OdinSidebar";
 import OdinThread from "./OdinThread";
 import InvoiceReviewCard from "./InvoiceReviewCard";
 import OdinComposer from "./OdinComposer";
@@ -87,13 +87,10 @@ export default function OdinChat() {
   const threadRef = useRef<HTMLDivElement>(null);
   const seededId = useRef<number | null>(null);
 
-  // Select the first existing conversation once the list loads (lazy-create:
-  // a brand-new user has none until they send the first message or press "+").
-  useEffect(() => {
-    if (!convPending && activeId == null && conversations.length > 0) {
-      setActiveId(conversations[0].id);
-    }
-  }, [convPending, conversations, activeId]);
+  // No auto-select: like claude.ai, we land on a fresh "new chat" (activeId
+  // null) and the sidebar lists existing conversations to open. A conversation
+  // row in the DB is created lazily on the first message (see submit), so
+  // pressing "Nová konverzace" repeatedly never spawns empty conversations.
 
   // Seed the thread from the active conversation's messages, once per id.
   useEffect(() => {
@@ -185,13 +182,6 @@ export default function OdinChat() {
     if (!text && files.length === 0) return;
 
     setBusy(true);
-    const convId = await ensureActive();
-    if (convId == null) {
-      setBusy(false);
-      alert.error("Nepodařilo se vytvořit konverzaci");
-      return;
-    }
-    seededId.current = convId;
     const prevTurns = turns;
 
     const userContent = [
@@ -247,10 +237,13 @@ export default function OdinChat() {
         setTurns((t) => [...t, { role: "assistant", content: note }]);
         setInput("");
         setAttachments([]);
-        persist(convId, [
-          { role: "user", content: userContent },
-          { role: "assistant", content: note },
-        ]);
+        // Create the conversation now (first successful message) and persist.
+        const convId = await ensureActive();
+        if (convId != null)
+          persist(convId, [
+            { role: "user", content: userContent },
+            { role: "assistant", content: note },
+          ]);
         qc.invalidateQueries({ queryKey: ["ai", "usage"] });
       } else {
         let ctx = optimistic.slice(-MODEL_CONTEXT);
@@ -265,10 +258,13 @@ export default function OdinChat() {
         const reply: string = body.data.reply;
         setTurns((t) => [...t, { role: "assistant", content: reply }]);
         setInput("");
-        persist(convId, [
-          { role: "user", content: userContent },
-          { role: "assistant", content: reply },
-        ]);
+        // Create the conversation now (first successful message) and persist.
+        const convId = await ensureActive();
+        if (convId != null)
+          persist(convId, [
+            { role: "user", content: userContent },
+            { role: "assistant", content: reply },
+          ]);
         qc.invalidateQueries({ queryKey: ["ai", "usage"] });
       }
     } catch (e) {
@@ -317,24 +313,16 @@ export default function OdinChat() {
     }
   };
 
-  const onNew = async () => {
+  // "Nová konverzace" just opens a fresh, empty composer — no DB row is created
+  // until the first message, so repeated clicks never spawn empty conversations.
+  const onNew = () => {
     if (busy) return;
-    const res = await apiFetch("/api/admin/ai/conversations", {
-      method: "POST",
-      headers: { "Content-Type": "application/json" },
-      body: JSON.stringify({}),
-    });
-    const b = await res.json();
-    if (res.ok && b?.data?.conversation) {
-      const id = b.data.conversation.id as number;
-      seededId.current = id;
-      setActiveId(id);
-      setTurns([]);
-      setReview([]);
-      qc.invalidateQueries({ queryKey: ["ai", "conversations"] });
-    } else {
-      alert.error("Nepodařilo se vytvořit konverzaci");
-    }
+    setActiveId(null);
+    setTurns([]);
+    setReview([]);
+    setInput("");
+    setAttachments([]);
+    seededId.current = null;
   };
 
   const onRename = async (id: number, title: string) => {
@@ -356,8 +344,8 @@ export default function OdinChat() {
       return;
     }
     if (id === activeId) {
-      const next = conversations.find((c) => c.id !== id)?.id ?? null;
-      setActiveId(next);
+      // Deleting the open conversation returns to a fresh new chat.
+      setActiveId(null);
       setTurns([]);
       setReview([]);
       seededId.current = null;
@@ -370,55 +358,22 @@ export default function OdinChat() {
       r.map((inv) => (inv.uid === uid ? { ...inv, [field]: value } : inv)),
     );
 
+  const activeTitle =
+    conversations.find((c) => c.id === activeId)?.title ?? "Nová konverzace";
+
   return (
     <Box
       sx={{
         height: "calc(100dvh - 100px)",
         display: "flex",
-        flexDirection: "column",
-        gap: 1.5,
         border: 1,
         borderColor: "divider",
         borderRadius: 3,
         bgcolor: "background.paper",
-        p: 2,
+        overflow: "hidden",
       }}
     >
-      <Box
-        sx={{
-          display: "flex",
-          justifyContent: "space-between",
-          alignItems: "center",
-        }}
-      >
-        <Box sx={{ display: "flex", alignItems: "center", gap: 1 }}>
-          <Box
-            sx={{
-              px: 0.75,
-              py: 0.25,
-              borderRadius: 1,
-              fontSize: 11,
-              fontWeight: 700,
-              letterSpacing: 0.5,
-              color: "common.white",
-              bgcolor: "primary.main",
-            }}
-          >
-            AI
-          </Box>
-          <Typography variant="subtitle1" sx={{ fontWeight: 600 }}>
-            Odin
-          </Typography>
-        </Box>
-        {usage && (
-          <Typography variant="caption" color="text.secondary">
-            Utraceno: ${usage.month_spend_usd.toFixed(2)} / $
-            {usage.budget_usd.toFixed(2)}
-          </Typography>
-        )}
-      </Box>
-
-      <OdinTabs
+      <OdinSidebar
         conversations={conversations}
         activeId={activeId}
         busy={busy}
@@ -428,50 +383,89 @@ export default function OdinChat() {
         onDelete={onDelete}
       />
 
-      <OdinThread
-        turns={turns}
-        busy={busy}
-        loading={messagesLoading}
-        threadRef={threadRef}
-      />
-
-      {review.length > 0 && (
+      {/* Chat column */}
+      <Box
+        sx={{
+          flex: 1,
+          minWidth: 0,
+          display: "flex",
+          flexDirection: "column",
+          gap: 1.5,
+          p: 2,
+        }}
+      >
         <Box
           sx={{
-            maxHeight: "35vh",
-            overflowY: "auto",
             display: "flex",
-            flexDirection: "column",
+            justifyContent: "space-between",
+            alignItems: "center",
             gap: 1,
           }}
         >
-          {review.map((inv) => (
-            <InvoiceReviewCard
-              key={inv.uid}
-              inv={inv}
-              busy={busy}
-              canSave={canSave}
-              onChange={patch}
-              onSave={saveInvoice}
-              onDiscard={(uid) =>
-                setReview((r) => r.filter((x) => x.uid !== uid))
-              }
-            />
-          ))}
+          <Typography
+            variant="subtitle1"
+            noWrap
+            sx={{ fontWeight: 600, minWidth: 0 }}
+          >
+            {activeTitle}
+          </Typography>
+          {usage && (
+            <Typography
+              variant="caption"
+              color="text.secondary"
+              sx={{ flexShrink: 0 }}
+            >
+              Utraceno: ${usage.month_spend_usd.toFixed(2)} / $
+              {usage.budget_usd.toFixed(2)}
+            </Typography>
+          )}
         </Box>
-      )}
 
-      <OdinComposer
-        input={input}
-        attachments={attachments}
-        busy={busy}
-        canSubmit={canSubmit}
-        fileRef={fileRef}
-        onInput={setInput}
-        onFiles={onFiles}
-        onRemoveAttachment={removeAttachment}
-        onSubmit={submit}
-      />
+        <OdinThread
+          turns={turns}
+          busy={busy}
+          loading={messagesLoading}
+          threadRef={threadRef}
+        />
+
+        {review.length > 0 && (
+          <Box
+            sx={{
+              maxHeight: "35vh",
+              overflowY: "auto",
+              display: "flex",
+              flexDirection: "column",
+              gap: 1,
+            }}
+          >
+            {review.map((inv) => (
+              <InvoiceReviewCard
+                key={inv.uid}
+                inv={inv}
+                busy={busy}
+                canSave={canSave}
+                onChange={patch}
+                onSave={saveInvoice}
+                onDiscard={(uid) =>
+                  setReview((r) => r.filter((x) => x.uid !== uid))
+                }
+              />
+            ))}
+          </Box>
+        )}
+
+        <OdinComposer
+          input={input}
+          attachments={attachments}
+          busy={busy}
+          canSubmit={canSubmit}
+          fileRef={fileRef}
+          onInput={setInput}
+          onFiles={onFiles}
+          onRemoveAttachment={removeAttachment}
+          onSubmit={submit}
+        />
+      </Box>
     </Box>
   );
 }

src/admin/components/odin/OdinSidebar.tsx

@@ -0,0 +1,224 @@
+import { useState } from "react";
+import Box from "@mui/material/Box";
+import Typography from "@mui/material/Typography";
+import Menu from "@mui/material/Menu";
+import MenuItem from "@mui/material/MenuItem";
+import IconButton from "@mui/material/IconButton";
+import { Button, TextField, Modal, ConfirmDialog } from "../../ui";
+
+interface OdinSidebarProps {
+  conversations: { id: number; title: string }[];
+  activeId: number | null;
+  busy: boolean;
+  onSelect: (id: number) => void;
+  onNew: () => void;
+  onRename: (id: number, title: string) => void;
+  onDelete: (id: number) => void;
+}
+
+export default function OdinSidebar({
+  conversations,
+  activeId,
+  busy,
+  onSelect,
+  onNew,
+  onRename,
+  onDelete,
+}: OdinSidebarProps) {
+  const [anchorEl, setAnchorEl] = useState<HTMLElement | null>(null);
+  const [menuConv, setMenuConv] = useState<{
+    id: number;
+    title: string;
+  } | null>(null);
+  const [renameOpen, setRenameOpen] = useState(false);
+  const [renameDraft, setRenameDraft] = useState("");
+  const [deleteOpen, setDeleteOpen] = useState(false);
+
+  const openMenu = (
+    e: React.MouseEvent<HTMLElement>,
+    conv: { id: number; title: string },
+  ) => {
+    e.stopPropagation();
+    setMenuConv(conv);
+    setAnchorEl(e.currentTarget);
+  };
+  const closeMenu = () => setAnchorEl(null);
+
+  const handleRenameOpen = () => {
+    closeMenu();
+    setRenameDraft(menuConv?.title ?? "");
+    setRenameOpen(true);
+  };
+  const handleRenameSubmit = () => {
+    if (menuConv) onRename(menuConv.id, renameDraft.trim() || menuConv.title);
+    setRenameOpen(false);
+  };
+  const handleDeleteOpen = () => {
+    closeMenu();
+    setDeleteOpen(true);
+  };
+  const handleDeleteConfirm = () => {
+    if (menuConv) onDelete(menuConv.id);
+    setDeleteOpen(false);
+  };
+
+  return (
+    <Box
+      sx={{
+        width: { xs: 184, sm: 232, md: 264 },
+        flexShrink: 0,
+        height: "100%",
+        display: "flex",
+        flexDirection: "column",
+        borderRight: 1,
+        borderColor: "divider",
+        bgcolor: "action.hover",
+      }}
+    >
+      {/* Brand + New chat */}
+      <Box sx={{ p: 1.5, display: "flex", flexDirection: "column", gap: 1 }}>
+        <Box sx={{ display: "flex", alignItems: "center", gap: 1, px: 0.5 }}>
+          <Box
+            sx={{
+              px: 0.75,
+              py: 0.25,
+              borderRadius: 1,
+              fontSize: 11,
+              fontWeight: 700,
+              letterSpacing: 0.5,
+              color: "common.white",
+              bgcolor: "primary.main",
+            }}
+          >
+            AI
+          </Box>
+          <Typography variant="subtitle1" sx={{ fontWeight: 600 }}>
+            Odin
+          </Typography>
+        </Box>
+        <Button fullWidth disabled={busy} onClick={onNew}>
+          + Nová konverzace
+        </Button>
+      </Box>
+
+      {/* Conversation list */}
+      <Box
+        sx={{
+          flex: 1,
+          minHeight: 0,
+          overflowY: "auto",
+          px: 1,
+          pb: 1,
+          display: "flex",
+          flexDirection: "column",
+          gap: 0.25,
+        }}
+      >
+        {conversations.length === 0 && (
+          <Typography
+            variant="caption"
+            color="text.secondary"
+            sx={{ px: 1, py: 1 }}
+          >
+            Zatím žádné konverzace.
+          </Typography>
+        )}
+        {conversations.map((conv) => {
+          const isActive = conv.id === activeId;
+          return (
+            <Box
+              key={conv.id}
+              onClick={() => !busy && onSelect(conv.id)}
+              sx={{
+                display: "flex",
+                alignItems: "center",
+                gap: 0.5,
+                px: 1,
+                py: 0.75,
+                borderRadius: 1.5,
+                cursor: busy ? "default" : "pointer",
+                bgcolor: isActive ? "action.selected" : "transparent",
+                "&:hover": {
+                  bgcolor: isActive ? "action.selected" : "action.hover",
+                },
+                "&:hover .odin-conv-menu": { opacity: 1 },
+              }}
+            >
+              <Typography
+                variant="body2"
+                noWrap
+                title={conv.title}
+                sx={{
+                  flex: 1,
+                  minWidth: 0,
+                  color: "text.primary",
+                  fontWeight: isActive ? 600 : 400,
+                }}
+              >
+                {conv.title}
+              </Typography>
+              <IconButton
+                className="odin-conv-menu"
+                size="small"
+                disabled={busy}
+                onClick={(e) => openMenu(e, conv)}
+                aria-label="Možnosti konverzace"
+                title="Možnosti konverzace"
+                sx={{
+                  flexShrink: 0,
+                  opacity: { xs: 1, md: 0 },
+                  transition: "opacity 0.15s",
+                }}
+              >
+                ⋮
+              </IconButton>
+            </Box>
+          );
+        })}
+      </Box>
+
+      {/* Per-conversation menu */}
+      <Menu anchorEl={anchorEl} open={Boolean(anchorEl)} onClose={closeMenu}>
+        <MenuItem onClick={handleRenameOpen}>Přejmenovat</MenuItem>
+        <MenuItem onClick={handleDeleteOpen}>Smazat</MenuItem>
+      </Menu>
+
+      {/* Rename modal */}
+      <Modal
+        isOpen={renameOpen}
+        onClose={() => setRenameOpen(false)}
+        onSubmit={handleRenameSubmit}
+        title="Přejmenovat konverzaci"
+        submitText="Přejmenovat"
+        maxWidth="xs"
+      >
+        <Box sx={{ pt: 1 }}>
+          <TextField
+            label="Název"
+            fullWidth
+            value={renameDraft}
+            onChange={(e) => setRenameDraft(e.target.value)}
+            onKeyDown={(e) => {
+              if (e.key === "Enter") {
+                e.preventDefault();
+                handleRenameSubmit();
+              }
+            }}
+            autoFocus
+          />
+        </Box>
+      </Modal>
+
+      {/* Delete confirm */}
+      <ConfirmDialog
+        isOpen={deleteOpen}
+        onClose={() => setDeleteOpen(false)}
+        onConfirm={handleDeleteConfirm}
+        title="Smazat konverzaci"
+        message={`Opravdu chcete smazat konverzaci „${menuConv?.title ?? ""}"? Tuto akci nelze vrátit.`}
+        confirmText="Smazat"
+        confirmVariant="danger"
+      />
+    </Box>
+  );
+}

src/admin/components/odin/OdinTabs.tsx

@@ -1,164 +0,0 @@
-import { useState } from "react";
-import Box from "@mui/material/Box";
-import Menu from "@mui/material/Menu";
-import MenuItem from "@mui/material/MenuItem";
-import IconButton from "@mui/material/IconButton";
-import { Button, TextField, Modal, ConfirmDialog } from "../../ui";
-
-interface OdinTabsProps {
-  conversations: { id: number; title: string }[];
-  activeId: number | null;
-  busy: boolean;
-  onSelect: (id: number) => void;
-  onNew: () => void;
-  onRename: (id: number, title: string) => void;
-  onDelete: (id: number) => void;
-}
-
-export default function OdinTabs({
-  conversations,
-  activeId,
-  busy,
-  onSelect,
-  onNew,
-  onRename,
-  onDelete,
-}: OdinTabsProps) {
-  const [anchorEl, setAnchorEl] = useState<HTMLElement | null>(null);
-  const [renameOpen, setRenameOpen] = useState(false);
-  const [renameDraft, setRenameDraft] = useState("");
-  const [deleteOpen, setDeleteOpen] = useState(false);
-
-  const activeConv = conversations.find((c) => c.id === activeId) ?? null;
-
-  const openMenu = (e: React.MouseEvent<HTMLElement>) => {
-    e.stopPropagation();
-    setAnchorEl(e.currentTarget);
-  };
-  const closeMenu = () => setAnchorEl(null);
-
-  const handleRenameOpen = () => {
-    closeMenu();
-    setRenameDraft(activeConv?.title ?? "");
-    setRenameOpen(true);
-  };
-
-  const handleRenameSubmit = () => {
-    if (activeId !== null) {
-      onRename(activeId, renameDraft.trim() || (activeConv?.title ?? ""));
-    }
-    setRenameOpen(false);
-  };
-
-  const handleDeleteOpen = () => {
-    closeMenu();
-    setDeleteOpen(true);
-  };
-
-  const handleDeleteConfirm = () => {
-    if (activeId !== null) {
-      onDelete(activeId);
-    }
-    setDeleteOpen(false);
-  };
-
-  return (
-    <>
-      <Box
-        sx={{
-          display: "flex",
-          gap: 0.5,
-          overflowX: "auto",
-          pb: 0.5,
-          alignItems: "center",
-        }}
-      >
-        {conversations.map((conv) => {
-          const isActive = conv.id === activeId;
-          return (
-            <Box
-              key={conv.id}
-              sx={{ display: "flex", alignItems: "center", flexShrink: 0 }}
-            >
-              <Button
-                size="small"
-                variant={isActive ? "contained" : "outlined"}
-                color={isActive ? "primary" : "inherit"}
-                disabled={busy}
-                onClick={() => onSelect(conv.id)}
-              >
-                {conv.title}
-              </Button>
-              {isActive && (
-                <IconButton
-                  size="small"
-                  disabled={busy}
-                  onClick={openMenu}
-                  aria-label="Možnosti konverzace"
-                  title="Možnosti konverzace"
-                  sx={{ ml: 0.25 }}
-                >
-                  ⋮
-                </IconButton>
-              )}
-            </Box>
-          );
-        })}
-
-        <Button
-          size="small"
-          variant="outlined"
-          color="inherit"
-          disabled={busy}
-          onClick={onNew}
-          sx={{ flexShrink: 0 }}
-        >
-          +
-        </Button>
-      </Box>
-
-      {/* Overflow menu */}
-      <Menu anchorEl={anchorEl} open={Boolean(anchorEl)} onClose={closeMenu}>
-        <MenuItem onClick={handleRenameOpen}>Přejmenovat</MenuItem>
-        <MenuItem onClick={handleDeleteOpen}>Smazat</MenuItem>
-      </Menu>
-
-      {/* Rename modal */}
-      <Modal
-        isOpen={renameOpen}
-        onClose={() => setRenameOpen(false)}
-        onSubmit={handleRenameSubmit}
-        title="Přejmenovat konverzaci"
-        submitText="Přejmenovat"
-        maxWidth="xs"
-      >
-        <Box sx={{ pt: 1 }}>
-          <TextField
-            label="Název"
-            fullWidth
-            value={renameDraft}
-            onChange={(e) => setRenameDraft(e.target.value)}
-            onKeyDown={(e) => {
-              if (e.key === "Enter") {
-                e.preventDefault();
-                handleRenameSubmit();
-              }
-            }}
-            autoFocus
-          />
-        </Box>
-      </Modal>
-
-      {/* Delete confirm */}
-      <ConfirmDialog
-        isOpen={deleteOpen}
-        onClose={() => setDeleteOpen(false)}
-        onConfirm={handleDeleteConfirm}
-        title="Smazat konverzaci"
-        message={`Opravdu chcete smazat konverzaci „${activeConv?.title ?? ""}"? Tuto akci nelze vrátit.`}
-        confirmText="Smazat"
-        confirmVariant="danger"
-      />
-    </>
-  );
-}