kandev/apps/web/lib/state/dockview-store.ts

/* eslint-disable max-lines -- zustand god-store; splitting is a separate refactor. */
import { create } from "zustand";
import type { DockviewApi, AddPanelOptions, SerializedDockview } from "dockview-react";
import {
  setEnvLayout,
  getEnvLayout,
  getEnvLayoutProfile,
  setEnvLayoutProfile,
  getEnvMaximizeState,
  setEnvMaximizeState,
  removeEnvMaximizeState,
  clearGlobalSidebarWidth,
  setGlobalSidebarWidth,
  getManualRightWidth,
} from "@/lib/local-storage";
import { getLayoutProfileIdentity, type LayoutProfileIdentity } from "@/lib/layout/layout-profiles";
import { setPinnedTarget, clearPinnedTarget } from "./layout-manager";
import { applyLayoutFixups, focusOrAddPanel } from "./dockview-layout-builders";
import {
  SIDEBAR_GROUP,
  CENTER_GROUP,
  RIGHT_TOP_GROUP,
  RIGHT_BOTTOM_GROUP,
  getPresetLayout,
  applyLayout,
  computePinnedMaxPxFor,
  getPinnedWidth,
  getRootSplitview,
  LAYOUT_PINNED_MIN_PX,
  fromDockviewApi,
  isRightColumn as isLayoutRightColumn,
  filterEphemeral,
  mergeCurrentPanelsIntoPreset,
  toSerializedDockview,
  normalizeReusableSessionPanels,
  materializeReusableChatPanel,
} from "./layout-manager";
import type { BuiltInPreset, LayoutState, LayoutGroupIds } from "./layout-manager";
import type { CommitDetailTarget } from "@/components/task/changes-diff-target";
import type { ReviewItemSummary } from "@/lib/plugins/types";
import { performEnvSwitch, replaceStaleSessionPanels } from "./dockview-env-switch";
import {
  captureRightPane,
  getRightPaneToggleState,
  readHiddenRightPane,
  restoreRightPane,
  withHiddenRightPaneMetadata,
  type HiddenRightPane,
} from "./dockview-right-pane";
import { enforcePinnedTargets } from "./dockview-pinned-enforce";
import {
  injectIntentPanels,
  applyActivePanelOverrides,
  resolveNamedIntent,
} from "./layout-manager";
import { buildFileStateActions } from "./dockview-file-state";
import {
  buildPanelActions,
  type OpenPanelOpts,
  type PreviewType,
  type ReviewPanelOptions,
} from "./dockview-panel-actions";
import { buildExtraPanelActions } from "./dockview-extra-panel-actions";
import { preserveChatScrollDuringLayout } from "./dockview-scroll-preserve";
import { measureDockviewContainer } from "./dockview-measure";
import { panelPortalManager } from "@/lib/layout/panel-portal-manager";
import { createDebugLogger, isDebug } from "@/lib/debug/log";
import {
  snapshotColumnWidths,
  formatWidthsSnapshot,
  formatJsonRootSizes,
} from "./dockview-widths-debug";

const debugSwitch = createDebugLogger("dockview:store-switch");
const debugSave = createDebugLogger("dockview:save");
const debugWidths = createDebugLogger("dockview:widths");

const DEFAULT_LAYOUT_PROFILE: LayoutProfileIdentity = { kind: "built-in", id: "default" };

function profileForCustomLayout(layout: Pick<SavedLayoutConfig, "id">): LayoutProfileIdentity {
  return getLayoutProfileIdentity(layout);
}

function inferLayoutProfileFromApi(api: DockviewApi): LayoutProfileIdentity {
  const changesPanel = api.getPanel("changes");
  const panelIds = changesPanel?.group.panels.map((panel) => panel.id) ?? [];
  if (
    changesPanel?.group.id === RIGHT_TOP_GROUP &&
    panelIds.length === 2 &&
    panelIds.includes("files")
  ) {
    return DEFAULT_LAYOUT_PROFILE;
  }
  return { kind: "custom", id: "restored-layout" };
}

/** Resolve the profile identity for an env restore, with a legacy shape fallback. */
export function resolveRestoredLayoutProfile(
  api: DockviewApi,
  envId: string | null,
): LayoutProfileIdentity {
  return (envId && getEnvLayoutProfile(envId)) || inferLayoutProfileFromApi(api);
}

function resolveEnvSwitchProfile(args: {
  hasFirstAdoptionRouteLayout: boolean;
  savedEnvLayout: object | null;
  savedLayoutProfile: LayoutProfileIdentity | null;
  currentLayoutProfile: LayoutProfileIdentity;
  api: DockviewApi;
}): LayoutProfileIdentity {
  if (args.hasFirstAdoptionRouteLayout) return args.currentLayoutProfile;
  if (args.savedLayoutProfile) return args.savedLayoutProfile;
  if (args.savedEnvLayout) return inferLayoutProfileFromApi(args.api);
  return args.currentLayoutProfile;
}

function resolveDefaultLayoutProfile(
  basePreset: BuiltInPreset | undefined,
  userDefaultLayout: LayoutState | null,
  userDefaultLayoutProfile: LayoutProfileIdentity,
  defaultPreset: BuiltInPreset,
): LayoutProfileIdentity {
  if (basePreset) return { kind: "built-in", id: basePreset };
  if (userDefaultLayout) return userDefaultLayoutProfile;
  return { kind: "built-in", id: defaultPreset };
}

// Re-export types and constants used by other modules
export type { BuiltInPreset } from "./layout-manager";
export {
  LAYOUT_SIDEBAR_RATIO,
  LAYOUT_RIGHT_RATIO,
  computeSidebarMaxPx,
  computeRightMaxPx,
  LAYOUT_PINNED_MIN_PX,
} from "./layout-manager";
export { applyLayoutFixups } from "./dockview-layout-builders";

export type FileEditorState = {
  path: string;
  /**
   * Multi-repo subpath (the repository_name, e.g. "enrichment-commons") this
   * file belongs to; `path` is interpreted relative to it. Undefined for
   * single-repo tasks. Threaded into every workspace file request so the
   * backend resolves the file under the right repository directory instead of
   * the bare task root.
   */
  repo?: string;
  name: string;
  content: string;
  originalContent: string;
  originalHash: string;
  isDirty: boolean;
  isBinary?: boolean;
  resolvedPath?: string;
  hasRemoteUpdate?: boolean;
  remoteContent?: string;
  remoteOriginalHash?: string;
  renderedPreview?: boolean;
};

/** Direction relative to a reference panel or group. */
export type PanelDirection = "left" | "right" | "above" | "below";

/** A deferred panel operation applied after the next layout build / restore. */
export type DeferredPanelAction = {
  id: string;
  component: string;
  title: string;
  placement: "tab" | PanelDirection;
  referencePanel?: string;
  params?: Record<string, unknown>;
};

/** Saved layout configuration persisted to user settings. */
export type SavedLayoutConfig = {
  id: string;
  name: string;
  isDefault: boolean;
  layout: Record<string, unknown>;
  createdAt: string;
};

export type ApplyCustomLayoutOptions = {
  activeSessionId?: string | null;
  sessionIds?: string[];
};
export type TranscriptScrollTarget = {
  sessionId: string;
  messageId: string;
  token: number;
  hostPanelId: string;
};

type DockviewStore = {
  api: DockviewApi | null;
  setApi: (api: DockviewApi | null) => void;
  openFiles: Map<string, FileEditorState>;
  setFileState: (path: string, state: FileEditorState) => void;
  updateFileState: (path: string, updates: Partial<FileEditorState>) => void;
  removeFileState: (path: string) => void;
  clearFileStates: () => void;
  buildDefaultLayout: (api: DockviewApi, intentName?: string) => void;
  resetLayout: () => void;
  addChatPanel: () => void;
  addChangesPanel: (groupId?: string) => void;
  addFilesPanel: (groupId?: string) => void;
  addDiffViewerPanel: (path?: string, content?: string, groupId?: string) => void;
  addFileDiffPanel: (
    path: string,
    opts?: OpenPanelOpts & {
      content?: string;
      groupId?: string;
      source?: string;
      repositoryName?: string;
      prKey?: string;
      changeLayer?: import("@/components/task/changes-diff-target").ChangeLayer;
    },
  ) => void;
  addCommitDetailPanel: (
    target: CommitDetailTarget | string,
    opts?: OpenPanelOpts & { groupId?: string; repo?: string },
  ) => void;
  addFileEditorPanel: (path: string, name: string, opts?: OpenPanelOpts) => void;
  promotePreviewToPinned: (type: PreviewType) => void;
  addBrowserPanel: (url?: string, groupId?: string) => void;
  /** Focus the existing preview browser, or open one when there is none. */
  focusOrAddBrowserPanel: (groupId?: string) => void;
  openBrowserPanel: (url: string) => void;
  addVscodePanel: () => void;
  openInternalVscode: (goto_: { file: string; line: number; col: number } | null) => void;
  addPlanPanel: (opts?: { groupId?: string; quiet?: boolean; inCenter?: boolean }) => void;
  /** Open a plugin-contributed task panel (Approach A1). title comes from the plugin's registration. */
  addPluginPanel: (
    pluginId: string,
    panelKey: string,
    title: string,
    opts?: { groupId?: string; quiet?: boolean; inCenter?: boolean },
  ) => void;
  /** Close every currently-open panel contributed by pluginId (disable/uninstall — AC4). */
  closePluginPanels: (pluginId: string) => void;
  addTodosPanel: (opts?: { groupId?: string; quiet?: boolean; inCenter?: boolean }) => void;
  addPromptHistoryPanel: (opts?: { groupId?: string; quiet?: boolean; inCenter?: boolean }) => void;
  /** Open a PR detail panel. prKey (owner/repo/pr_number) gives multi-repo tasks one tab per PR. */
  addPRPanel: (prKey?: string, opts?: ReviewPanelOptions) => void;
  /** Open a GitLab merge request detail panel keyed by host/project/iid. */
  addMRPanel: (mrKey: string, opts?: ReviewPanelOptions) => void;
  /** Open a provider-neutral review detail panel. */
  addReviewPanel: (
    review: Pick<
      ReviewItemSummary,
      | "providerId"
      | "reviewKey"
      | "connectionScope"
      | "repositoryId"
      | "changeRequestNumber"
      | "title"
    >,
    opts?: ReviewPanelOptions,
  ) => void;
  addTerminalPanel: (
    terminalId?: string,
    groupId?: string,
    environmentId?: string,
    taskID?: string,
    title?: string,
  ) => void;
  /** Read-only output panel for the repository dev script. */
  addDevServerPanel: (groupId?: string) => void;
  selectedDiff: { path: string; content?: string } | null;
  setSelectedDiff: (diff: { path: string; content?: string } | null) => void;
  scrollTarget: TranscriptScrollTarget | null;
  scrollTranscriptToMessage: (sessionId: string, messageId: string, title: string) => boolean;
  clearScrollTarget: (token: number) => void;
  clearScrollTargetForOwner: (sessionId: string, hostPanelId: string) => void;
  activeGroupId: string | null;
  centerGroupId: string;
  rightTopGroupId: string;
  rightBottomGroupId: string;
  sidebarGroupId: string;
  sidebarVisible: boolean;
  rightPanelsVisible: boolean;
  rightPaneVisible: boolean;
  rightPaneAvailable: boolean;
  hiddenRightPane: HiddenRightPane | null;
  /** Identity of the active built-in or saved custom layout profile. */
  activeLayoutProfile: LayoutProfileIdentity;
  toggleSidebar: () => void;
  toggleRightPanels: () => void;
  setSidebarVisible: (visible: boolean) => void;
  setRightPanelsVisible: (visible: boolean) => void;
  refreshRightPaneState: () => void;
  applyBuiltInPreset: (preset: BuiltInPreset, resetWidths?: boolean) => void;
  defaultPreset: BuiltInPreset;
  setDefaultPreset: (preset: BuiltInPreset) => void;
  applyCustomLayout: (layout: SavedLayoutConfig, opts?: ApplyCustomLayoutOptions) => void;
  captureCurrentLayout: () => Record<string, unknown>;
  isRestoringLayout: boolean;
  /** ID of the task environment whose layout is currently rendered. Layouts are
   *  keyed by env so sessions sharing an env reuse one layout. */
  currentLayoutEnvId: string | null;
  /** Switch the rendered layout to a new task environment. Same-env switches
   *  are a no-op (the layout already belongs to that env). `activeSessionId`
   *  is the session whose chat panel should be present in the new env. */
  switchEnvLayout: (
    oldEnvId: string | null,
    newEnvId: string,
    activeSessionId: string | null,
    currentSessionIds?: string[],
    initialLayout?: string | null,
  ) => void;
  deferredPanelActions: DeferredPanelAction[];
  queuePanelAction: (action: DeferredPanelAction) => void;
  pinnedWidths: Map<string, number>;
  setPinnedWidth: (columnId: string, width: number) => void;
  userDefaultLayout: LayoutState | null;
  userDefaultLayoutProfile: LayoutProfileIdentity;
  setUserDefaultLayout: (layout: LayoutState | null, profile: LayoutProfileIdentity) => void;
  activeFilePath: string | null;
  activeFileRepo: string | null;
  activePanelComponent: string | null;
  pendingChatScrollTop: number | null;
  setPendingChatScrollTop: (value: number | null) => void;
  pendingChatInitialPlacement: { sessionId: string; token: number } | null;
  completePendingChatInitialPlacement: (token: number) => void;
  /** Saved layout from before a manual maximize. Null when not maximized. */
  preMaximizeLayout: LayoutState | null;
  /** The group ID that was maximized (used for session restore). */
  maximizedGroupId: string | null;
  maximizeGroup: (groupId: string) => void;
  exitMaximizedLayout: () => void;
};

type StoreGet = () => DockviewStore;
type StoreSet = (
  partial: Partial<DockviewStore> | ((s: DockviewStore) => Partial<DockviewStore>),
) => void;

let chatInitialPlacementToken = 0;

function nextChatInitialPlacementToken(): number {
  chatInitialPlacementToken += 1;
  return chatInitialPlacementToken;
}

function createChatInitialPlacement(sessionId: string | null) {
  return sessionId ? { sessionId, token: nextChatInitialPlacementToken() } : null;
}

/**
 * Apply queued deferred panel actions to the dockview API after a layout
 * build/restore. "tab" placements land in the reference panel's group; other
 * placements position the new panel relative to the reference panel
 * (defaulting to the chat panel).
 */
function applyDeferredPanelActions(api: DockviewApi, actions: DeferredPanelAction[]): void {
  for (const action of actions) {
    const ref = action.referencePanel ?? "chat";
    let position: AddPanelOptions["position"];
    if (action.placement === "tab") {
      const groupId = api.getPanel(ref)?.group?.id;
      if (groupId) position = { referenceGroup: groupId };
    } else {
      position = { referencePanel: ref, direction: action.placement };
    }
    focusOrAddPanel(api, {
      id: action.id,
      component: action.component,
      title: action.title,
      position,
      ...(action.params ? { params: action.params } : {}),
    });
  }
}

/**
 * Build the pinnedWidths updates for a width sync, tracking only the VISIBLE
 * default right column.
 *
 * In plan/preview/vscode layouts a side column can inherit merged files or
 * changes panels. The serializer preserves the center/right ownership before
 * this sync runs, so only the canonical right column receives the override.
 *
 * Sidebar is intentionally excluded: its persisted width is a global pref
 * written only by explicit sash drag, and syncing live layout-change widths
 * would overwrite the raw pref with viewport-clamped transient widths.
 * Widths <= 50px are treated as transient/collapsed and skipped.
 */
export function collectPinnedWidthUpdates(
  columns: { id: string }[],
  getSize: (index: number) => number,
  visibility: { rightPanelsVisible: boolean },
): Map<string, number> {
  const updates = new Map<string, number>();
  columns.forEach((col, i) => {
    if (col.id !== "right" || !visibility.rightPanelsVisible) return;
    const w = getSize(i);
    if (w > 50) updates.set(col.id, w);
  });
  return updates;
}

/** Read live column widths from dockview's splitview and persist the visible
 *  right width as a pinned override (see `collectPinnedWidthUpdates`). */
function syncPinnedWidthsFromApi(api: DockviewApi, set: StoreSet): void {
  if (api.hasMaximizedGroup()) return;
  const sv = getRootSplitview(api);
  if (!sv || sv.length < 2) return;
  try {
    const state = fromDockviewApi(api);
    if (state.columns.length !== sv.length) return;
    const { rightPanelsVisible, currentLayoutEnvId } = useDockviewStore.getState();
    if (getManualRightWidth(currentLayoutEnvId) === null) return;
    const updates = collectPinnedWidthUpdates(state.columns, (i) => sv.getViewSize(i), {
      rightPanelsVisible,
    });
    if (updates.size > 0) {
      if (isDebug()) {
        const pairs = Array.from(updates.entries())
          .map(([k, v]) => `${k}=${Math.round(v)}`)
          .join(",");
        debugWidths(`store-sync ${pairs} ${formatWidthsSnapshot(snapshotColumnWidths(api))}`);
      }
      set((prev) => {
        const m = new Map(prev.pinnedWidths);
        for (const [k, v] of updates) m.set(k, v);
        return { pinnedWidths: m };
      });
    }
  } catch {
    /* noop */
  }
}

/**
 * Decide which pinned-width overrides to apply when switching to a preset.
 *
 * - `resetWidths` (explicit layout pick from the selector): return each pinned
 *   column's computed DEFAULT width (ratio clamped to its initial cap). These
 *   are passed as explicit overrides — NOT an empty map — so `applyLayout`'s
 *   resize-to-target path is used. An empty map makes it read the
 *   post-`fromJSON` live size instead, which is fragile: dockview can lay
 *   `fromJSON` out at a transient narrower width, and that shrunken size would
 *   be captured as the pinned target and then enforced, leaving the columns
 *   too narrow.
 * - otherwise (programmatic switch, e.g. plan-mode toggle): keep the live right
 *   width, minus overrides for columns absent in the target layout. Sidebar is
 *   always resolved from the global pref/default instead of an in-memory
 *   override.
 */
export function resolvePresetPinnedWidths(
  liveWidths: Map<string, number>,
  columns: LayoutState["columns"],
  totalWidth: number,
  resetWidths: boolean,
): Map<string, number> {
  if (resetWidths) {
    // "Default layout" is the reset gesture: drop any custom global sidebar
    // width (and its runtime target) so getPinnedWidth returns the fresh
    // ratio default for the current screen instead of re-reading the pref.
    clearGlobalSidebarWidth();
    clearPinnedTarget("sidebar");
    const defaults = new Map<string, number>();
    for (const col of columns) {
      if (col.pinned) defaults.set(col.id, getPinnedWidth(col, totalWidth, undefined));
    }
    return defaults;
  }
  const targetColumnIds = new Set(columns.map((c) => c.id));
  const cleaned = new Map(liveWidths);
  for (const key of cleaned.keys()) {
    if (key === "sidebar" || !targetColumnIds.has(key)) cleaned.delete(key);
  }
  return cleaned;
}

/**
 * Resolve pinned widths stored by a reusable/custom layout for the current
 * workbench. Selecting a saved layout is an explicit geometry change, so its
 * own widths take precedence over the task's currently live pinned widths. A
 * complete snapshot is scaled proportionally to the current workbench before
 * runtime caps apply. Incomplete snapshots retain valid absolute pinned widths;
 * invalid/missing pinned widths are omitted so the normal ratio default applies.
 */
export function resolveCustomLayoutPinnedWidths(
  columns: LayoutState["columns"],
  totalWidth: number,
): Map<string, number> {
  const widths = new Map<string, number>();
  /** True when the column carries a finite, positive saved width. */
  const hasValidWidth = (column: LayoutState["columns"][number]): boolean =>
    typeof column.width === "number" && Number.isFinite(column.width) && column.width > 0;
  const hasCompleteGeometry =
    columns.length > 0 && columns.every((column) => hasValidWidth(column));
  const savedTotal = hasCompleteGeometry
    ? columns.reduce((total, column) => total + (column.width ?? 0), 0)
    : 0;

  /**
   * Resolve a column's saved width to a pixel width: scaled proportionally to
   * the current workbench when every column has a valid saved width, otherwise
   * used as-is, then clamped to the column's min/max bounds.
   */
  const resolveColumn = (column: LayoutState["columns"][number], sidebarWidth = 0): number => {
    const savedWidth = column.width;
    if (typeof savedWidth !== "number") return 0;
    const requestedWidth = hasCompleteGeometry
      ? Math.round((savedWidth / savedTotal) * totalWidth)
      : savedWidth;
    const min = column.minWidth ?? LAYOUT_PINNED_MIN_PX;
    const max =
      column.maxWidth ?? computePinnedMaxPxFor(column.id, totalWidth, sidebarWidth || undefined);
    return Math.max(min, Math.min(requestedWidth, max));
  };

  const sidebar = columns.find(
    (column) => column.id === "sidebar" && column.pinned && hasValidWidth(column),
  );
  const sidebarWidth = sidebar ? resolveColumn(sidebar) : 0;
  if (sidebarWidth > 0) widths.set("sidebar", sidebarWidth);

  for (const column of columns) {
    if (column.id === "sidebar" || !column.pinned || !hasValidWidth(column)) continue;
    widths.set(column.id, resolveColumn(column, sidebarWidth));
  }
  return widths;
}

/** Capture the live right pixel width into pinnedWidths before a layout rebuild. */
function captureLiveWidths(api: DockviewApi, set: StoreSet): Map<string, number> {
  if (api.hasMaximizedGroup()) {
    api.exitMaximizedGroup();
  }
  syncPinnedWidthsFromApi(api, set);
  return useDockviewStore.getState().pinnedWidths;
}

/**
 * Snap pinned columns to their targets using the current store state.
 *
 * Called inside every programmatic layout path's post-`api.layout` rAF
 * before flipping `isRestoringLayout` false - dockview's proportional
 * rebalance can grow pinned columns up to their loose `setConstraints` max,
 * and the reactive enforcement (wired via `onDidLayoutChange`) is gated by
 * `isRestoringLayout`, so without this synchronous call the correction
 * would only land on the next user-triggered layout-change event,
 * producing a visible jerk once env prep settles.
 */
function enforceFromStore(api: DockviewApi, get: StoreGet): void {
  const s = get();
  enforcePinnedTargets(api, {
    sidebarVisible: s.sidebarVisible,
    rightPanelsVisible: s.rightPanelsVisible,
    maximized: s.preMaximizeLayout !== null,
    envId: s.currentLayoutEnvId,
  });
}

/**
 * Apply a layout state to the dockview API and persist the resulting group
 * IDs to the store. Uses the caller-provided `preMeasured` container size when
 * supplied, otherwise measures the dockview container itself.
 */
function applyLayoutAndSet(
  api: DockviewApi,
  state: LayoutState,
  pinnedWidths: Map<string, number>,
  set: StoreSet,
  preMeasured?: { width: number; height: number },
): LayoutGroupIds {
  // Pass measured container dims so fromJSON's grid.width matches the live
  // container — avoids the proportional rescale that would otherwise grow
  // pinned columns past their legacy initial caps on the next api.layout.
  //
  // Callers can pre-measure and pass `preMeasured` to avoid re-measuring inside
  // the middle of a layout transition. The visibility toggles below take that
  // path because `set({ sidebarVisible: ... })` runs before this call and can
  // trigger React to repaint the host shell, momentarily shrinking the
  // dockview parent's `clientWidth` — re-measuring then would read the
  // transient narrow width and clamp pinned columns to it (the
  // `pane-resize-sidebar.spec.ts:41` flake mode: cap=301 from a 601px stale
  // measurement clamps the 430px sidebar override down to 301).
  const measured = preMeasured ?? measureDockviewContainer(api);
  const previousLayout = typeof api.toJSON === "function" ? api.toJSON() : undefined;
  try {
    const ids = applyLayout(api, state, pinnedWidths, measured.width, measured.height);
    set(ids);
    return ids;
  } catch (error) {
    // Dockview can clear its grid before reporting a deserialization error. Roll back once so
    // every programmatic layout transition either commits completely or leaves the live grid intact.
    try {
      if (previousLayout) {
        api.fromJSON(previousLayout);
      }
    } catch {
      // A failed rollback cannot be repaired by retrying without risking another partial mutation.
    }
    throw error;
  }
}

function restoreSerializedDockview(api: DockviewApi, next: SerializedDockview): void {
  const previous = api.toJSON();
  try {
    api.fromJSON(next);
  } catch (error) {
    try {
      api.fromJSON(previous);
    } catch {
      // A failed rollback cannot be repaired by retrying without risking another partial mutation.
    }
    throw error;
  }
}

/** True when the column belongs to the right-side workbench surface. */
export const isRightColumn = isLayoutRightColumn;

export function hasRightColumn(state: LayoutState): boolean {
  return state.columns.some(isRightColumn);
}

function visibilityForLayout(
  layout: LayoutState,
  hiddenRightPane: HiddenRightPane | null,
): Pick<DockviewStore, "rightPanelsVisible" | "rightPaneVisible" | "rightPaneAvailable"> {
  if (!Array.isArray(layout.columns)) {
    return {
      rightPanelsVisible: false,
      rightPaneVisible: false,
      rightPaneAvailable: false,
    };
  }
  const paneState = getRightPaneToggleState(layout, hiddenRightPane);
  return {
    rightPanelsVisible: hasRightColumn(layout),
    rightPaneVisible: paneState.visible,
    rightPaneAvailable: paneState.available,
  };
}

/** Build the store's visibility actions for the contextual right pane. */
function buildVisibilityActions(set: StoreSet, get: StoreGet) {
  return {
    // Legacy dockview-embedded sidebar is gone after the unified AppSidebar
    // landed; the keybinding redirects to the AppSidebar toggle elsewhere.
    // We keep these on the store as no-ops so any stragglers compile cleanly.
    toggleSidebar: () => {
      /* moved to UI slice: toggleAppSidebar */
    },
    toggleRightPanels: () => {
      const { api, hiddenRightPane, preMaximizeLayout } = get();
      if (!api || preMaximizeLayout) return;
      const targetEnvId = get().currentLayoutEnvId;
      const liveWidths = captureLiveWidths(api, set);
      preserveChatScrollDuringLayout();
      const { width: safeWidth, height: safeHeight } = measureDockviewContainer(api);
      const current = fromDockviewApi(api);
      let nextLayout: LayoutState;
      let nextHiddenRightPane: HiddenRightPane | null;
      if (hiddenRightPane) {
        const restored = restoreRightPane(current, hiddenRightPane, {
          totalWidth: safeWidth,
          pinnedWidths: liveWidths,
        });
        if (!restored) {
          set({ hiddenRightPane: null, ...visibilityForLayout(current, null) });
          return;
        }
        nextLayout = restored;
        nextHiddenRightPane = null;
      } else {
        const captured = captureRightPane(current);
        if (!captured) {
          set({ hiddenRightPane: null, ...visibilityForLayout(current, null) });
          return;
        }
        nextLayout = captured.layout;
        nextHiddenRightPane = captured.hiddenRightPane;
      }

      set({
        isRestoringLayout: true,
        hiddenRightPane: nextHiddenRightPane,
        ...visibilityForLayout(nextLayout, nextHiddenRightPane),
      });

      try {
        applyLayoutAndSet(api, nextLayout, liveWidths, set);
      } catch {
        set({
          isRestoringLayout: false,
          hiddenRightPane,
          ...visibilityForLayout(current, hiddenRightPane),
        });
        return;
      }

      requestAnimationFrame(() => {
        api.layout(safeWidth, safeHeight);
        enforceFromStore(api, get);
        syncPinnedWidthsFromApi(api, set);
        set({ isRestoringLayout: false });
        const { currentLayoutEnvId, preMaximizeLayout } = get();
        if (currentLayoutEnvId === targetEnvId) {
          persistEnvLayoutNow(api, targetEnvId, preMaximizeLayout);
        }
      });
    },

    setSidebarVisible: (_visible: boolean) => {
      /* moved to UI slice: setAppSidebarCollapsed */
    },
    setRightPanelsVisible: (visible: boolean) => {
      const { rightPaneVisible } = get();
      if (rightPaneVisible === visible) return;
      get().toggleRightPanels();
    },
    refreshRightPaneState: () => {
      const { api, hiddenRightPane } = get();
      if (!api) return;
      const current = fromDockviewApi(api);
      const paneState = getRightPaneToggleState(current, hiddenRightPane);
      const nextHidden = hiddenRightPane && !paneState.hidden ? null : hiddenRightPane;
      set({ hiddenRightPane: nextHidden, ...visibilityForLayout(current, nextHidden) });
    },
  };
}

/**
 * Build the store's preset/custom-layout actions. `applyBuiltInPreset`
 * switches to a built-in preset (merging current panels, optionally resetting
 * widths), `applyCustomLayout` restores a saved custom layout, and
 * `captureCurrentLayout` snapshots the current layout for reuse.
 */
function buildPresetActions(set: StoreSet, get: StoreGet) {
  return {
    applyBuiltInPreset: (preset: BuiltInPreset, resetWidths = false) => {
      const { api } = get();
      if (!api) return;
      const liveWidths = captureLiveWidths(api, set);
      preserveChatScrollDuringLayout();
      // Capture before layout change; api.width can become stale in rAF.
      const { width: safeWidth, height: safeHeight } = measureDockviewContainer(api);
      set({
        isRestoringLayout: true,
        hiddenRightPane: null,
        activeLayoutProfile: { kind: "built-in", id: preset },
      });
      const presetState = getPresetLayout(preset);
      const state = mergeCurrentPanelsIntoPreset(api, presetState);
      // resetWidths (explicit pick from the layout selector) → preset defaults;
      // otherwise carry live widths minus columns absent in the target layout.
      const cleanedWidths = resolvePresetPinnedWidths(
        liveWidths,
        state.columns,
        safeWidth,
        resetWidths,
      );
      const ids = applyLayoutAndSet(api, state, cleanedWidths, set, {
        width: safeWidth,
        height: safeHeight,
      });
      if (isDebug()) {
        const applied =
          [...cleanedWidths].map(([k, v]) => `${k}:${Math.round(v)}`).join(",") || "-";
        debugWidths(
          `preset-apply preset=${preset} reset=${resetWidths} safeW=${safeWidth} ` +
            `applied=${applied} postApply=${formatWidthsSnapshot(snapshotColumnWidths(api))}`,
        );
      }
      set({
        ...ids,
        sidebarVisible: true,
        ...visibilityForLayout(state, null),
        pinnedWidths: cleanedWidths,
      });
      const targetEnvId = get().currentLayoutEnvId;
      requestAnimationFrame(() => {
        api.layout(safeWidth, safeHeight);
        if (isDebug()) {
          debugWidths(
            `preset-post-layout preset=${preset} ${formatWidthsSnapshot(snapshotColumnWidths(api))}`,
          );
        }
        enforceFromStore(api, get);
        syncPinnedWidthsFromApi(api, set);
        set({ isRestoringLayout: false });
        const { currentLayoutEnvId, preMaximizeLayout } = get();
        if (currentLayoutEnvId === targetEnvId) {
          persistEnvLayoutNow(api, targetEnvId, preMaximizeLayout);
        }
      });
    },
    applyCustomLayout: (layout: SavedLayoutConfig, opts?: ApplyCustomLayoutOptions) => {
      const { api } = get();
      if (!api) return;
      captureLiveWidths(api, set);
      preserveChatScrollDuringLayout();
      const { width: safeWidth, height: safeHeight } = measureDockviewContainer(api);
      set({
        isRestoringLayout: true,
        hiddenRightPane: null,
        activeLayoutProfile: profileForCustomLayout(layout),
      });
      const { appliedState, oldFormatRestoreFailed } = restoreCustomLayout({
        api,
        layout,
        opts,
        safeWidth,
        safeHeight,
        set,
      });
      const hasSidebar = !!api.getPanel("sidebar");
      const restoredLayout = fromDockviewApi(api);
      const effectiveLayout = restoredLayout.columns.length > 0 ? restoredLayout : appliedState;
      set({
        sidebarVisible: hasSidebar,
        ...visibilityForLayout(effectiveLayout, null),
      });
      const targetEnvId = get().currentLayoutEnvId;
      requestAnimationFrame(() => {
        api.layout(safeWidth, safeHeight);
        enforceFromStore(api, get);
        syncPinnedWidthsFromApi(api, set);
        set({ isRestoringLayout: false });
        const { currentLayoutEnvId, preMaximizeLayout } = get();
        // Don't persist when the legacy fromJSON restore threw: the API may be in a partial state and snapshotting it would propagate corruption to the next load.
        if (currentLayoutEnvId === targetEnvId && !oldFormatRestoreFailed) {
          persistEnvLayoutNow(api, targetEnvId, preMaximizeLayout);
        }
      });
    },
    captureCurrentLayout: () => captureReusableLayout(get),
  };
}

type RestoreCustomLayoutParams = {
  api: DockviewApi;
  layout: SavedLayoutConfig;
  opts: ApplyCustomLayoutOptions | undefined;
  safeWidth: number;
  safeHeight: number;
  set: StoreSet;
};

/**
 * Restore a saved custom layout onto the dockview API. New-format layouts
 * (with columns) are normalized (reusable session panels, chat materialization)
 * and applied with resolved pinned widths; legacy serialized blobs are
 * restored via `api.fromJSON`. Returns the applied state and whether a legacy
 * restore threw.
 */
function restoreCustomLayout({
  api,
  layout,
  opts,
  safeWidth,
  safeHeight,
  set,
}: RestoreCustomLayoutParams): { appliedState: LayoutState; oldFormatRestoreFailed: boolean } {
  const state = layout.layout as unknown as LayoutState;
  if (state?.columns) {
    // Normalize first so both old saved layouts with session-specific panels
    // and newer reusable layouts with chat placeholders apply through one path.
    const activeState = materializeReusableChatPanel(
      normalizeReusableSessionPanels(state),
      opts?.activeSessionId ?? null,
      opts?.sessionIds ?? [],
    );
    const savedWidths = resolveCustomLayoutPinnedWidths(activeState.columns, safeWidth);
    const ids = applyLayoutAndSet(api, activeState, savedWidths, set, {
      width: safeWidth,
      height: safeHeight,
    });
    set({ ...ids, pinnedWidths: savedWidths });
    return { appliedState: activeState, oldFormatRestoreFailed: false };
  }

  try {
    restoreSerializedDockview(api, layout.layout as unknown as SerializedDockview);
    replaceStaleSessionPanels(api, opts?.activeSessionId ?? null, opts?.sessionIds ?? []);
    set(applyLayoutFixups(api));
    return { appliedState: state, oldFormatRestoreFailed: false };
  } catch (e) {
    console.warn("applyCustomLayout: old-format restore failed:", e);
    return { appliedState: state, oldFormatRestoreFailed: true };
  }
}

/**
 * Capture the current layout as a reusable snapshot: ephemeral panels are
 * filtered out and session panels are normalized to reusable placeholders.
 */
function captureReusableLayout(get: StoreGet): Record<string, unknown> {
  const { api } = get();
  if (!api) return {};
  const state = fromDockviewApi(api);
  const filtered = filterEphemeral(state);
  return normalizeReusableSessionPanels(filtered) as unknown as Record<string, unknown>;
}

/** Restore a saved maximize state from sessionStorage onto the dockview API. */
function restoreMaximizeFromStorage(
  api: DockviewApi,
  envId: string,
  set: StoreSet,
  activeSessionId: string | null,
  currentSessionIds: string[] = [],
): boolean {
  const saved = getEnvMaximizeState(envId);
  if (!saved) return false;
  try {
    restoreSerializedDockview(api, saved.maximizedDockviewJson as SerializedDockview);
    replaceStaleSessionPanels(api, activeSessionId, currentSessionIds);
    // After fromJSON, `api.width/height` reflect the JSON's recorded grid
    // dims, which may not match the live container. Always lay out against
    // the measured DOM size so a stale value can't pin the dockview at the
    // wrong width on subsequent restores.
    const { width, height } = measureDockviewContainer(api);
    api.layout(width, height);
    const ids = applyLayoutFixups(api, undefined, getManualRightWidth(envId));
    const preMax = saved.preMaximizeLayout as unknown as LayoutState;
    // The maximized layout is `[sidebar?, maximized]` — the non-sidebar group
    // is the one being maximized, which `resolveGroupIds` returns as
    // `centerGroupId`. Tracking it keeps the store consistent with what
    // `maximizeGroup` would have set (so toggle/exit logic doesn't operate on
    // a half-restored maximize).
    set({
      ...ids,
      preMaximizeLayout: preMax,
      maximizedGroupId: ids.centerGroupId,
      ...visibilityForLayout(preMax, readHiddenRightPane(getEnvLayout(envId))),
    });
  } catch {
    // Drop the bad blob so the next switch/reload doesn't keep reattempting
    // the same failing fromJSON before falling back. Self-healing.
    removeEnvMaximizeState(envId);
    return false;
  }
  requestAnimationFrame(() => {
    set({ isRestoringLayout: false });
  });
  return true;
}

function restoreIncomingMaximize(args: {
  api: DockviewApi;
  envId: string;
  set: StoreSet;
  activeSessionId: string | null;
  currentSessionIds: string[];
  hasFirstAdoptionRouteLayout: boolean;
  savedLayoutProfile: LayoutProfileIdentity | null;
}): boolean {
  if (args.hasFirstAdoptionRouteLayout) return false;
  if (
    !restoreMaximizeFromStorage(
      args.api,
      args.envId,
      args.set,
      args.activeSessionId,
      args.currentSessionIds,
    )
  ) {
    return false;
  }
  args.set({
    activeLayoutProfile: args.savedLayoutProfile ?? inferLayoutProfileFromApi(args.api),
  });
  return true;
}

// Persist settled layout to env storage; auto-save in setupLayoutPersistence is gated by isRestoringLayout, so preset/custom actions must call this after the flag clears.
/**
 * Persist the settled layout to the env's storage slot. No-op when maximized
 * (the maximize overlay is saved separately) or when envId is null; called
 * after preset/custom actions clear `isRestoringLayout`, since the auto-save
 * in setupLayoutPersistence is gated during restore.
 */
export function persistEnvLayoutNow(
  api: DockviewApi,
  envId: string | null,
  preMaximizeLayout: LayoutState | null,
): void {
  if (!envId) return;
  // While maximized, api.toJSON() is the 2-column overlay; the regular layout has its own slot via saveOutgoingEnv.
  if (preMaximizeLayout !== null) return;
  try {
    const state = useDockviewStore.getState();
    setEnvLayout(envId, withHiddenRightPaneMetadata(api.toJSON(), state.hiddenRightPane));
    setEnvLayoutProfile(envId, useDockviewStore.getState().activeLayoutProfile);
  } catch {
    /* ignore serialization/storage failures */
  }
}

function resolveEnvDefaultPinnedWidths(get: StoreGet, width: number): Map<string, number> {
  const defaultLayout = get().userDefaultLayout;
  return defaultLayout ? resolveCustomLayoutPinnedWidths(defaultLayout.columns, width) : new Map();
}

/** Save the outgoing env's layout & maximize state, then release its portals. */
function saveOutgoingEnv(
  api: DockviewApi,
  oldEnvId: string | null,
  preMaximizeLayout: LayoutState | null,
  pinnedWidths: Map<string, number>,
): void {
  if (!oldEnvId) {
    debugSave("saveOutgoingEnv: skip (no oldEnvId)");
    return;
  }
  if (isDebug()) {
    debugSave("saveOutgoingEnv: entry", {
      oldEnvId,
      livePanelIds: api.panels.map((p) => p.id),
      maximized: !!preMaximizeLayout,
    });
  }
  if (preMaximizeLayout) {
    // While maximized, `api.toJSON()` is the 2-column maximize overlay, NOT
    // the user's intended layout. Persist the pre-max layout under both keys:
    //  - max state: maximizedDockviewJson is what the user sees (the overlay);
    //  - env layout: pre-max serialized so a reload that misses the max state
    //    (e.g. cleared maximize) falls back to the user's real layout, not a
    //    truncated 2-column slice.
    // Wrapped in try/catch so a serialization throw can't skip releaseByEnv at
    // the bottom (which would re-leak env-scoped portals).
    try {
      setEnvMaximizeState(oldEnvId, {
        preMaximizeLayout: preMaximizeLayout as unknown as object,
        maximizedDockviewJson: api.toJSON(),
      });
    } catch (err) {
      removeEnvMaximizeState(oldEnvId);
      console.warn("saveOutgoingEnv: failed to persist maximize state", err);
    }
    try {
      // Use measured container size — `api.width/height` can be drifted from
      // the live container, and serializing with stale dims would persist a
      // shrunken layout that resurfaces on the next reload.
      const { width, height } = measureDockviewContainer(api);
      const preMaxSerialized = toSerializedDockview(preMaximizeLayout, width, height, pinnedWidths);
      setEnvLayout(
        oldEnvId,
        withHiddenRightPaneMetadata(
          preMaxSerialized as unknown as object,
          useDockviewStore.getState().hiddenRightPane,
        ),
      );
      setEnvLayoutProfile(oldEnvId, useDockviewStore.getState().activeLayoutProfile);
    } catch (err) {
      console.warn("saveOutgoingEnv: serialize failed", err);
      /* fall back: skip writing rather than overwrite with maximized JSON */
    }
  } else {
    removeEnvMaximizeState(oldEnvId);
    try {
      const json = api.toJSON();
      setEnvLayout(
        oldEnvId,
        withHiddenRightPaneMetadata(json, useDockviewStore.getState().hiddenRightPane),
      );
      setEnvLayoutProfile(oldEnvId, useDockviewStore.getState().activeLayoutProfile);
      if (isDebug()) {
        debugWidths(
          `save-outgoing env=${oldEnvId} ${formatWidthsSnapshot(snapshotColumnWidths(api))} ` +
            `jsonSizes=${formatJsonRootSizes(json)}`,
        );
      }
    } catch {
      /* ignore */
    }
  }
  panelPortalManager.releaseByEnv(oldEnvId);
}

/**
 * Build the `switchEnvLayout` action: persists and releases the outgoing
 * env's layout/portals, then restores the new env's saved layout (or a saved
 * maximized state), falling back to the default layout. Same-env switches
 * are a no-op.
 */
function buildEnvSwitchAction(set: StoreSet, get: StoreGet) {
  return (
    oldEnvId: string | null,
    newEnvId: string,
    activeSessionId: string | null,
    currentSessionIds: string[] = [],
    initialLayout?: string | null,
  ) => {
    const { api, currentLayoutEnvId, preMaximizeLayout } = get();
    if (!api) {
      debugSwitch("envSwitch: skip (no api)", { oldEnvId, newEnvId, activeSessionId });
      return;
    }
    if (isDebug()) {
      debugSwitch("envSwitch: entry", {
        oldEnvId,
        newEnvId,
        activeSessionId,
        currentLayoutEnvId,
        maximized: !!preMaximizeLayout,
        livePanelIds: api.panels.map((p) => p.id),
      });
    }
    // Same-env switch (e.g. between sessions of the same task) is a no-op.
    // The layout, terminals, and env-scoped portals already belong to this env.
    if (currentLayoutEnvId === newEnvId) {
      debugSwitch("envSwitch: skip (same env)", { newEnvId });
      return;
    }
    set({ pendingChatInitialPlacement: createChatInitialPlacement(activeSessionId) });
    // First adoption (oldEnvId and currentLayoutEnvId both null) falls through
    // to the general path below. We deliberately do NOT "just adopt" whatever
    // onReady rendered: this branch only fires when onReady ran with a null
    // env (otherwise currentLayoutEnvId would equal newEnvId and we'd have
    // skipped above as same-env), so onReady built the cross-env GLOBAL
    // FALLBACK layout — not this env's saved/default layout. Adopting it gave a
    // fresh task the previous env's stale proportions instead of the defaults,
    // and `setEnvLayout(newEnvId, api.toJSON())` even overwrote the env's real
    // saved layout with that stale one. `performEnvSwitch` instead restores the
    // env's saved layout (or builds defaults for a brand-new task), and
    // `saveOutgoingEnv(null)` below is a no-op so there is nothing to lose.
    //
    // When oldEnvId is null but there IS a live layout env (the
    // useEnvSwitchCleanup hook firing after passing through a null state),
    // fall back to currentLayoutEnvId so we correctly save and release the
    // outgoing env rather than silently skipping it.
    const effectiveOld = oldEnvId ?? currentLayoutEnvId;
    saveOutgoingEnv(api, effectiveOld, preMaximizeLayout, get().pinnedWidths);
    set({ preMaximizeLayout: null, maximizedGroupId: null });
    const manualRightWidth = getManualRightWidth(newEnvId);
    const savedEnvLayout = getEnvLayout(newEnvId);
    const hiddenRightPane = readHiddenRightPane(savedEnvLayout);
    const savedLayoutProfile = getEnvLayoutProfile(newEnvId);
    set({
      isRestoringLayout: true,
      currentLayoutEnvId: newEnvId,
      hiddenRightPane,
      pinnedWidths: manualRightWidth === null ? new Map() : new Map([["right", manualRightWidth]]),
    });
    try {
      const hasFirstAdoptionRouteLayout =
        oldEnvId === null && currentLayoutEnvId === null && Boolean(initialLayout);
      if (
        restoreIncomingMaximize({
          api,
          envId: newEnvId,
          set,
          activeSessionId,
          currentSessionIds,
          hasFirstAdoptionRouteLayout,
          savedLayoutProfile,
        })
      )
        return;
      const measured = measureDockviewContainer(api);
      const ids = performEnvSwitch({
        api,
        oldEnvId: effectiveOld,
        newEnvId,
        activeSessionId,
        currentSessionIds,
        safeWidth: measured.width,
        safeHeight: measured.height,
        buildDefault: (a, intentName) => get().buildDefaultLayout(a, intentName),
        getDefaultLayout: () => get().userDefaultLayout ?? getPresetLayout(get().defaultPreset),
        getDefaultPinnedWidths: (width) => resolveEnvDefaultPinnedWidths(get, width),
        initialLayout,
      });
      const restoredLayout = fromDockviewApi(api);
      set({
        ...ids,
        ...visibilityForLayout(restoredLayout, get().hiddenRightPane),
        activeLayoutProfile: resolveEnvSwitchProfile({
          hasFirstAdoptionRouteLayout,
          savedEnvLayout,
          savedLayoutProfile,
          currentLayoutProfile: get().activeLayoutProfile,
          api,
        }),
      });
      enforceFromStore(api, get);
      set({ isRestoringLayout: false });
      if (isDebug()) {
        debugWidths(
          `env-switch-done old=${effectiveOld ?? "-"} new=${newEnvId} ` +
            `${formatWidthsSnapshot(snapshotColumnWidths(api))}`,
        );
      }
      panelPortalManager.reconcile(new Set(api.panels.map((p) => p.id)));
    } catch {
      set({ isRestoringLayout: false });
    }
  };
}

/**
 * Build the maximize actions. `maximizeGroup` collapses the layout to the
 * sidebar plus the requested group, persisting the pre-maximize layout (and
 * a saved maximize state for the current env); `exitMaximizedLayout` restores
 * that pre-maximize layout and clears the saved maximize state.
 */
function buildMaximizeActions(set: StoreSet, get: StoreGet) {
  return {
    maximizeGroup: (groupId: string) => {
      const { api, preMaximizeLayout, currentLayoutEnvId } = get();
      if (!api) return;
      if (preMaximizeLayout) {
        get().exitMaximizedLayout();
        return;
      }
      const liveWidths = captureLiveWidths(api, set);
      preserveChatScrollDuringLayout();
      const current = fromDockviewApi(api);
      let targetGroup: {
        panels: LayoutState["columns"][0]["groups"][0]["panels"];
        activePanel?: string;
      } | null = null;
      for (const col of current.columns) {
        for (const g of col.groups) {
          if (g.id === groupId) {
            targetGroup = { panels: g.panels, activePanel: g.activePanel };
            break;
          }
        }
        if (targetGroup) break;
      }
      if (!targetGroup || targetGroup.panels.length === 0) return;
      const sidebarCol = current.columns.find((c) => c.id === "sidebar");
      const columns: LayoutState["columns"] = [];
      if (sidebarCol) columns.push(sidebarCol);
      columns.push({
        id: "maximized",
        groups: [{ panels: targetGroup.panels, activePanel: targetGroup.activePanel }],
      });
      const maximizedLayout: LayoutState = { columns };
      set({
        isRestoringLayout: true,
        preMaximizeLayout: current,
        maximizedGroupId: groupId,
        ...visibilityForLayout(current, get().hiddenRightPane),
      });
      const { width: safeWidth, height: safeHeight } = measureDockviewContainer(api);
      applyLayoutAndSet(api, maximizedLayout, liveWidths, set);
      requestAnimationFrame(() => {
        api.layout(safeWidth, safeHeight);
        if (currentLayoutEnvId) {
          setEnvMaximizeState(currentLayoutEnvId, {
            preMaximizeLayout: current as unknown as object,
            maximizedDockviewJson: api.toJSON(),
          });
        }
        set({ isRestoringLayout: false });
      });
    },
    exitMaximizedLayout: () => {
      const { api, preMaximizeLayout, currentLayoutEnvId } = get();
      if (!api || !preMaximizeLayout) return;
      preserveChatScrollDuringLayout();
      const measured = measureDockviewContainer(api);
      const safeWidth = measured.width;
      const safeHeight = measured.height;
      const liveWidths = get().pinnedWidths;
      set({
        isRestoringLayout: true,
        preMaximizeLayout: null,
        maximizedGroupId: null,
        ...visibilityForLayout(preMaximizeLayout, get().hiddenRightPane),
      });
      if (currentLayoutEnvId) {
        removeEnvMaximizeState(currentLayoutEnvId);
      }
      applyLayoutAndSet(api, preMaximizeLayout, liveWidths, set);
      requestAnimationFrame(() => {
        api.layout(safeWidth, safeHeight);
        enforceFromStore(api, get);
        syncPinnedWidthsFromApi(api, set);
        set({ isRestoringLayout: false });
        persistEnvLayoutNow(api, currentLayoutEnvId, null);
      });
    },
  };
}

function resolveBuildDefaultPinnedWidths(
  state: LayoutState,
  userDefaultLayout: LayoutState | null,
  basePreset: BuiltInPreset | undefined,
  availableWidth: number,
): Map<string, number> {
  if (!userDefaultLayout || basePreset) return new Map();
  // Intent panel injection preserves column widths, so the effective state
  // still carries the saved custom-default geometry used for scaling.
  return resolveCustomLayoutPinnedWidths(state.columns, availableWidth);
}

/**
 * Build and apply the default layout — the user's saved default or the active
 * preset, optionally injected with an intent's panels/active-panel overrides —
 * then flush any deferred panel actions and re-enforce pinned targets once
 * the layout settles.
 */
function performBuildDefault(
  api: DockviewApi,
  set: StoreSet,
  get: StoreGet,
  intentName?: string,
): void {
  const { userDefaultLayout, userDefaultLayoutProfile } = get();
  const intent = intentName ? resolveNamedIntent(intentName) : null;
  // Capture dimensions before layout change — api.width can become stale
  // after fromJSON inside applyLayout
  const { width: safeWidth, height: safeHeight } = measureDockviewContainer(api);
  if (isDebug()) {
    debugWidths(
      `build-default-entry intent=${intentName ?? "-"} ` +
        `measured=${safeWidth}x${safeHeight} ` +
        `pre=${formatWidthsSnapshot(snapshotColumnWidths(api))}`,
    );
  }
  const basePreset = intent?.preset as BuiltInPreset | undefined;
  const activeLayoutProfile = resolveDefaultLayoutProfile(
    basePreset,
    userDefaultLayout,
    userDefaultLayoutProfile,
    get().defaultPreset,
  );

  let state = basePreset
    ? getPresetLayout(basePreset)
    : (userDefaultLayout ?? getPresetLayout(get().defaultPreset));

  if (intent?.panels?.length) {
    state = injectIntentPanels(state, intent.panels);
  }
  if (intent?.activePanels) {
    state = applyActivePanelOverrides(state, intent.activePanels);
  }

  const pinnedWidths = resolveBuildDefaultPinnedWidths(
    state,
    userDefaultLayout,
    basePreset,
    safeWidth,
  );
  set({
    isRestoringLayout: true,
    pinnedWidths,
    activeLayoutProfile,
    hiddenRightPane: null,
  });

  const ids = applyLayoutAndSet(api, state, pinnedWidths, set, {
    width: safeWidth,
    height: safeHeight,
  });
  const hasSidebar = state.columns.some((c) => c.id === "sidebar");
  set({ ...ids, sidebarVisible: hasSidebar, ...visibilityForLayout(state, null) });

  const pending = get().deferredPanelActions;
  if (pending.length > 0) {
    set({ deferredPanelActions: [] });
    applyDeferredPanelActions(api, pending);
  }

  requestAnimationFrame(() => {
    api.layout(safeWidth, safeHeight);
    enforceFromStore(api, get);
    syncPinnedWidthsFromApi(api, set);
    if (isDebug()) {
      debugWidths(`build-default-done ${formatWidthsSnapshot(snapshotColumnWidths(api))}`);
    }
    set({ isRestoringLayout: false });
  });
}

/**
 * Reset the dockview to the effective default layout: clear any maximize
 * state, rebuild the default layout, and persist the settled layout to the
 * current env's storage.
 */
function resetToEffectiveDefault(set: StoreSet, get: StoreGet): void {
  const { api, currentLayoutEnvId, preMaximizeLayout } = get();
  if (!api) {
    useDockviewStore.setState({ pendingChatInitialPlacement: null });
    return;
  }
  if (preMaximizeLayout) {
    set({ preMaximizeLayout: null, maximizedGroupId: null, hiddenRightPane: null });
    if (currentLayoutEnvId) removeEnvMaximizeState(currentLayoutEnvId);
  } else {
    set({ hiddenRightPane: null });
  }
  get().buildDefaultLayout(api);
  requestAnimationFrame(() => {
    const { currentLayoutEnvId: activeEnvId, preMaximizeLayout } = get();
    if (activeEnvId === currentLayoutEnvId) {
      persistEnvLayoutNow(api, currentLayoutEnvId, preMaximizeLayout);
    }
  });
}

type ActiveFileState = Pick<
  DockviewStore,
  "activeFilePath" | "activeFileRepo" | "activePanelComponent"
>;

/**
 * Infer the panel component from its id when the panel is not live in
 * dockview: `file-editor` for file/preview-editor ids and `diff-viewer` for
 * diff ids, otherwise null.
 */
function inferPanelComponent(panelId: string): string | null {
  if (panelId === "preview:file-editor" || panelId.startsWith("file:")) return "file-editor";
  if (panelId === "preview:file-diff" || panelId.startsWith("diff:file:")) return "diff-viewer";
  return null;
}

/** Build the active-file state slice (path, repo, and panel component). */
function activeFileState(
  activeFilePath: string | null,
  activeFileRepo: string | null,
  activePanelComponent: string | null,
): ActiveFileState {
  return { activeFilePath, activeFileRepo, activePanelComponent };
}

/**
 * Resolve the active file identity for a panel id: reads path/repo from the
 * panel's params, falling back to legacy bare-path `file:`/`diff:file:` ids.
 */
function resolveActiveFile(api: DockviewApi, panelId: string | undefined): ActiveFileState {
  if (!panelId) return activeFileState(null, null, null);
  const panel = api.getPanel(panelId);
  const activePanelComponent = panel?.api.component ?? inferPanelComponent(panelId);
  const params = panel?.params as Record<string, unknown> | undefined;
  const panelPath = typeof params?.path === "string" ? params.path : null;
  let panelRepo: string | null = null;
  if (typeof params?.repo === "string") panelRepo = params.repo;
  else if (typeof params?.repositoryName === "string") panelRepo = params.repositoryName;
  if (panelPath) return activeFileState(panelPath, panelRepo, activePanelComponent);

  // Legacy bare-path panel IDs did not encode repository scope. Modern
  // file/diff panels resolve through params above.
  if (panelId.startsWith("file:")) {
    return activeFileState(panelId.slice(5), null, activePanelComponent);
  }
  if (panelId.startsWith("diff:file:")) {
    return activeFileState(panelId.slice("diff:file:".length), null, activePanelComponent);
  }
  return activeFileState(null, null, activePanelComponent);
}

function buildSetApiAction(set: StoreSet): DockviewStore["setApi"] {
  return (api) => {
    set({
      api,
      activeFilePath: null,
      activeFileRepo: null,
      activePanelComponent: null,
    });
    if (typeof window !== "undefined") {
      // Exposed for E2E tests to assert on panel/group placement. Harmless in
      // prod; the DockviewApi is already reachable via the store in devtools.
      type TestWindow = {
        __dockviewApi__: DockviewApi | null;
        __setPinnedTarget__?: typeof setPinnedTarget;
        __setGlobalSidebarWidth__?: typeof setGlobalSidebarWidth;
      };
      const w = window as unknown as TestWindow;
      w.__dockviewApi__ = api;
      // E2E test helpers: let `resizeColumnViaSplitview` update the target
      // width after a programmatic resize (mirroring the sash-drag mouseup),
      // including persisting the global sidebar-width pref like a real drag.
      w.__setPinnedTarget__ = setPinnedTarget;
      w.__setGlobalSidebarWidth__ = setGlobalSidebarWidth;
    }
    if (!api) return;

    api.onDidActivePanelChange((event) => {
      set(resolveActiveFile(api, event?.id));
    });
    // Track per-panel param-change subscriptions so they can be disposed when
    // the panel is removed instead of relying on dockview's internal cleanup.
    const paramSubs = new Map<string, { dispose: () => void }>();
    api.onDidAddPanel((panel) => {
      // The preview file-editor panel reuses a single dockview panel and swaps
      // its params.path when the user previews a different file. Dockview does
      // not refire onDidActivePanelChange for params-only updates.
      if (panel.id !== "preview:file-editor" && panel.id !== "preview:file-diff") return;
      paramSubs.get(panel.id)?.dispose();
      const sub = panel.api.onDidParametersChange(() => {
        if (!panel.api.isActive) return;
        set(resolveActiveFile(api, panel.id));
      });
      paramSubs.set(panel.id, sub);
    });
    api.onDidRemovePanel((panel) => {
      const sub = paramSubs.get(panel.id);
      if (!sub) return;
      sub.dispose();
      paramSubs.delete(panel.id);
    });
  };
}

export const useDockviewStore = create<DockviewStore>((set, get) => ({
  api: null,
  activeFilePath: null,
  activeFileRepo: null,
  activePanelComponent: null,
  setApi: buildSetApiAction(set),
  activeGroupId: null,
  selectedDiff: null,
  setSelectedDiff: (diff) => set({ selectedDiff: diff }),
  scrollTarget: null,
  openFiles: new Map(),
  ...buildFileStateActions(set),
  centerGroupId: CENTER_GROUP,
  rightTopGroupId: RIGHT_TOP_GROUP,
  rightBottomGroupId: RIGHT_BOTTOM_GROUP,
  // Legacy fields preserved for backwards compatibility with code that still
  // reads them; the embedded dockview sidebar pane was removed in favour of
  // the unified AppSidebar. Treated as inert: sidebarVisible is always false.
  sidebarGroupId: SIDEBAR_GROUP,
  sidebarVisible: false,
  rightPanelsVisible: true,
  rightPaneVisible: true,
  rightPaneAvailable: false,
  hiddenRightPane: null,
  activeLayoutProfile: DEFAULT_LAYOUT_PROFILE,
  pinnedWidths: new Map(),
  setPinnedWidth: (columnId, width) => {
    set((prev) => {
      const m = new Map(prev.pinnedWidths);
      m.set(columnId, width);
      return { pinnedWidths: m };
    });
  },
  userDefaultLayout: null,
  userDefaultLayoutProfile: DEFAULT_LAYOUT_PROFILE,
  setUserDefaultLayout: (layout, profile) =>
    set({ userDefaultLayout: layout, userDefaultLayoutProfile: profile }),
  ...buildVisibilityActions(set, get),
  ...buildPresetActions(set, get),
  defaultPreset: "default",
  setDefaultPreset: (preset) => set({ defaultPreset: preset }),
  isRestoringLayout: false,
  currentLayoutEnvId: null,
  deferredPanelActions: [],
  queuePanelAction: (action) =>
    set((prev) => ({
      deferredPanelActions: [...prev.deferredPanelActions, action],
    })),
  switchEnvLayout: buildEnvSwitchAction(set, get),
  buildDefaultLayout: (api, intentName) => performBuildDefault(api, set, get, intentName),
  resetLayout: () => resetToEffectiveDefault(set, get),
  pendingChatScrollTop: null,
  setPendingChatScrollTop: (value) => set({ pendingChatScrollTop: value }),
  pendingChatInitialPlacement: null,
  completePendingChatInitialPlacement: (token) =>
    set((state) =>
      state.pendingChatInitialPlacement?.token === token
        ? { pendingChatInitialPlacement: null }
        : {},
    ),
  preMaximizeLayout: null,
  maximizedGroupId: null,
  ...buildMaximizeActions(set, get),
  ...buildPanelActions(set, get),
  ...buildExtraPanelActions(set, get),
}));

/**
 * Perform a layout switch between task environments. Same-env (e.g. between
 * sessions of the same task) is a no-op — terminals + layout stay put.
 *
 * `activeSessionId` is the session whose chat panel should be present in the
 * resulting layout. It can differ across sessions of the same env, but layout
 * reuse means we just ensure the right session: chat panel is visible.
 */
export function performLayoutSwitch(
  oldEnvId: string | null,
  newEnvId: string,
  activeSessionId: string | null,
  currentSessionIds: string[] = [],
  initialLayout?: string | null,
): void {
  useDockviewStore
    .getState()
    .switchEnvLayout(oldEnvId, newEnvId, activeSessionId, currentSessionIds, initialLayout);
}

/**
 * Release the dockview to a clean default layout — used when selecting a task
 * that has no session (and prepare failed to launch one). Without this the
 * dockview keeps the outgoing env's panels live but disconnected from any
 * active session, and the corrupted state can be persisted on the next save.
 *
 * Pre-setting `isRestoringLayout: true` suppresses `setupSessionTabSync` from
 * firing during the synchronous setState/saveOutgoingEnv window. Without this,
 * dockview can synchronously activate a stale `session:<sid>` panel (still
 * mounted from the outgoing env) while we rebuild defaults — poisoning
 * `lastSessionByTaskId[newTaskId]` with the previous task's session id.
 *
 * `buildDefaultLayout` (`performBuildDefault`) owns the success-path reset: it
 * re-asserts the flag synchronously and clears it inside its own rAF. We only
 * clear here on a synchronous throw so the flag does not get stuck.
 */
export function releaseLayoutToDefault(oldEnvId: string | null): void {
  const { api, currentLayoutEnvId, preMaximizeLayout, buildDefaultLayout, pinnedWidths } =
    useDockviewStore.getState();
  if (!api) return;
  const effectiveOld = oldEnvId ?? currentLayoutEnvId;
  saveOutgoingEnv(api, effectiveOld, preMaximizeLayout, pinnedWidths);
  useDockviewStore.setState({
    preMaximizeLayout: null,
    maximizedGroupId: null,
    currentLayoutEnvId: null,
    isRestoringLayout: true,
    pendingChatInitialPlacement: null,
  });
  try {
    buildDefaultLayout(api);
  } catch (e) {
    useDockviewStore.setState({ isRestoringLayout: false });
    throw e;
  }
}