Bugs: Template tab - isWebMode not set correctly when clicking/cloning web templates

[devin-ai-integration]

Bug Report: Template Tab Navigation Issues

Bug 1: Clicking a web template from TemplatesHomepage does not navigate to template details

Location: apps/desktop/src/components/main/body/templates/index.tsx

From TemplatesHomepage, clicking a web template card calls onSelectWebTemplate which maps to setSelectedWebIndex (line 210-220). This sets selectedWebIndex and showHomepage: false, but does not set isWebMode: true.

The default state created by getDefaultState sets isWebMode: null, and isWebMode is read as tab.state.isWebMode ?? userTemplates.length === 0 (line 174). Since the user never manually switched to web mode, isWebMode stays false (assuming the user has any templates). The TemplateDetailsColumn (details.tsx:33) checks isWebMode first — when it's false, it looks for selectedMineId instead of selectedWebTemplate, resulting in "Select a template to view details" being shown instead of the web template preview.

Expected: Clicking a web template from the homepage should show its details.
Actual: Nothing happens (empty detail pane) because isWebMode stays false.

Bug 2: Cloning a web template does not switch user to the cloned template

Location: apps/desktop/src/components/main/body/templates/index.tsx, handleCloneTemplate (line 267-291)

const handleCloneTemplate = useCallback(
  (template) => {
    // ... creates new template ...
    setIsWebMode(false);       // Call 1
    setSelectedMineId(newId);  // Call 2
  },
  [user_id, setRow, setIsWebMode, setSelectedMineId],
);

Both setIsWebMode and setSelectedMineId call updateTabState by spreading tab.state. Since both callbacks capture the same tab from the closure (React state hasn't updated yet), setSelectedMineId spreads the old tab.state which still has isWebMode: true (or null). This effectively overrides the isWebMode: false set by setIsWebMode.

Expected: After cloning, user should see the cloned template in "My Templates" mode.
Actual: isWebMode remains truthy, so the detail column stays in web mode.

Design Issue: isWebMode should be derived state

isWebMode is stored independently alongside selectedMineId and selectedWebIndex, allowing unrepresentable states such as:

• isWebMode: true with selectedMineId set
• isWebMode: false with selectedWebIndex set

isWebMode should ideally be derived from selectedMineId / selectedWebIndex (or a similar single source of truth), eliminating the class of bugs where these values get out of sync.

[devin-ai-integration]

Template Tab State Machine

State

TemplatesState = {
  showHomepage: boolean | null;  // controls Homepage vs List+Details view
  isWebMode: boolean | null;     // controls My Templates vs Web Templates in List+Details
  selectedMineId: string | null;
  selectedWebIndex: number | null;
}

Visual Modes

There are 3 visual modes determined by showHomepage and isWebMode:

stateDiagram-v2
    [*] --> Homepage: default state

    state "Homepage" as Homepage {
        note right of Homepage
            Left: Favorites sidebar (user templates)
            Right: Web template card grid + search + "Create your own"
        end note
    }

    state "List + Details (My Templates)" as MyTemplates {
        note right of MyTemplates
            Left: User template list, web toggle OFF
            Right: TemplateForm (if selectedMineId) or empty
        end note
    }

    state "List + Details (Web Templates)" as WebTemplates {
        note right of WebTemplates
            Left: Web template list, web toggle ON
            Right: WebTemplatePreview (if selectedWebIndex) or empty
        end note
    }

    Homepage --> MyTemplates: Click user template in Favorites\n(setSelectedMineId)
    Homepage --> MyTemplates: Click "Create your own"\n(handleCreateTemplate)
    Homepage --> WebTemplates: Click web template card\n⚠️ BUG: goes to MyTemplates instead\nbecause isWebMode not set to true

    MyTemplates --> Homepage: Click "Templates" header\n(setShowHomepage(true))
    MyTemplates --> WebTemplates: Toggle web switch ON\n(setIsWebMode(true))

    WebTemplates --> Homepage: Click "Templates" header\n(setShowHomepage(true))
    WebTemplates --> MyTemplates: Toggle web switch OFF\n(setIsWebMode(false))
    WebTemplates --> MyTemplates: Clone web template\n⚠️ BUG: stays in WebTemplates\nbecause setSelectedMineId overrides\nisWebMode from stale tab.state

Loading

Within-mode transitions

Mode	Action	State setter	Effect
Homepage	Click user template in Favorites	setSelectedMineId(id)	showHomepage→false, selectedMineId→id
Homepage	Click web template card	setSelectedWebIndex(idx)	showHomepage→false, selectedWebIndex→idx (but isWebMode stays false)
Homepage	Click "Create your own"	handleCreateTemplate()	Creates template → setIsWebMode(false) → setSelectedMineId(newId)
My Templates	Click a template	setSelectedMineId(id)	selectedMineId→id, selectedWebIndex→null
My Templates	Delete a template	handleDeleteTemplate(id)	Removes row, selectedMineId→null
Web Templates	Click a template	setSelectedWebIndex(idx)	selectedWebIndex→idx, selectedMineId→null
Web Templates	Clone a template	handleCloneTemplate(t)	Creates template → setIsWebMode(false) → setSelectedMineId(newId)

Unrepresentable states that are currently possible

showHomepage	isWebMode	selectedMineId	selectedWebIndex	Valid?
true	true	"abc"	3	No — homepage shouldn't have selections AND web mode
false	true	"abc"	null	No — web mode with a mine selection
false	false	null	3	No — non-web mode with a web selection
false	null	null	3	No — this is what Bug 1 produces

Suggested fix direction

Replace showHomepage + isWebMode + selectedMineId + selectedWebIndex with a single discriminated union:

type TemplatesMode =
  | { type: "homepage" }
  | { type: "my_templates"; selectedId: string | null }
  | { type: "web_templates"; selectedIndex: number | null };

This makes all invalid states unrepresentable by construction.