fix(core/mercury): show remaining shares

This commit enables showing "Remaining shares" from the context menu
during recovery process. This is only shown during super-shamir.

core/.changelog.d/4142.fixed

@@ -0,0 +1 @@
+[T3T1] Added missing info about remaining shares in super-shamir recovery.

core/embed/rust/src/ui/model_mercury/layout.rs

@@ -1013,31 +1013,6 @@ extern "C" fn new_show_group_share_success(
     unsafe { util::try_with_args_and_kwargs(n_args, args, kwargs, block) }
 }
 
-extern "C" fn new_show_remaining_shares(n_args: usize, args: *const Obj, kwargs: *mut Map) -> Obj {
-    let block = move |_args: &[Obj], kwargs: &Map| {
-        let pages_iterable: Obj = kwargs.get(Qstr::MP_QSTR_pages)?;
-
-        let mut paragraphs = ParagraphVecLong::new();
-        for page in IterBuf::new().try_iterate(pages_iterable)? {
-            let [title, description]: [TString; 2] = util::iter_into_array(page)?;
-            paragraphs
-                .add(Paragraph::new(&theme::TEXT_DEMIBOLD, title))
-                .add(Paragraph::new(&theme::TEXT_NORMAL, description).break_after());
-        }
-
-        let obj = LayoutObj::new(SwipeUpScreen::new(
-            Frame::left_aligned(
-                TR::recovery__title_remaining_shares.into(),
-                SwipeContent::new(paragraphs.into_paragraphs()),
-            )
-            .with_footer(TR::instructions__swipe_up.into(), None)
-            .with_swipe(SwipeDirection::Up, SwipeSettings::default()),
-        ))?;
-        Ok(obj.into())
-    };
-    unsafe { util::try_with_args_and_kwargs(n_args, args, kwargs, block) }
-}
-
 extern "C" fn new_show_progress(n_args: usize, args: *const Obj, kwargs: *mut Map) -> Obj {
     let block = move |_args: &[Obj], kwargs: &Map| {
         let description: TString = kwargs.get(Qstr::MP_QSTR_description)?.try_into()?;
@@ -1594,6 +1569,7 @@ pub static mp_module_trezorui2: Module = obj_module! {
     ///     recovery_type: RecoveryType,
     ///     text: str,
     ///     subtext: str | None = None,
+    ///     pages: Iterable[tuple[str, str]] | None = None,
     /// ) -> LayoutObj[UiResult]:
     ///     """Device recovery homescreen."""
     Qstr::MP_QSTR_flow_continue_recovery => obj_fn_kw!(0, flow::continue_recovery::new_continue_recovery).as_obj(),
@@ -1613,13 +1589,6 @@ pub static mp_module_trezorui2: Module = obj_module! {
     ///     """Shown after successfully finishing a group."""
     Qstr::MP_QSTR_show_group_share_success => obj_fn_kw!(0, new_show_group_share_success).as_obj(),
 
-    /// def show_remaining_shares(
-    ///     *,
-    ///     pages: Iterable[tuple[str, str]],
-    /// ) -> LayoutObj[UiResult]:
-    ///     """Shows SLIP39 state after info button is pressed on `confirm_recovery`."""
-    Qstr::MP_QSTR_show_remaining_shares => obj_fn_kw!(0, new_show_remaining_shares).as_obj(),
-
     /// def show_progress(
     ///     *,
     ///     title: str,

core/mocks/generated/trezorui2.pyi

@@ -452,6 +452,7 @@ def flow_continue_recovery(
     recovery_type: RecoveryType,
     text: str,
     subtext: str | None = None,
+    pages: Iterable[tuple[str, str]] | None = None,
 ) -> LayoutObj[UiResult]:
     """Device recovery homescreen."""
 
@@ -473,14 +474,6 @@ def show_group_share_success(
     """Shown after successfully finishing a group."""
 
 
-# rust/src/ui/model_mercury/layout.rs
-def show_remaining_shares(
-    *,
-    pages: Iterable[tuple[str, str]],
-) -> LayoutObj[UiResult]:
-    """Shows SLIP39 state after info button is pressed on `confirm_recovery`."""
-
-
 # rust/src/ui/model_mercury/layout.rs
 def show_progress(
     *,

core/src/apps/management/recovery_device/homescreen.py

@@ -13,6 +13,8 @@
 if TYPE_CHECKING:
     from trezor.enums import BackupType, RecoveryType
 
+    from .layout import RemainingSharesInfo
+
 
 async def recovery_homescreen() -> None:
     from trezor import workflow
@@ -297,7 +299,7 @@ async def _request_share_next_screen() -> None:
         await layout.homescreen_dialog(
             TR.buttons__enter,
             TR.recovery__more_shares_needed,
-            info_func=_show_remaining_groups_and_shares,
+            remaining_shares_info=_get_remaining_groups_and_shares(),
         )
     else:
         still_needed_shares = remaining[0]
@@ -315,37 +317,37 @@ async def _request_share_next_screen() -> None:
         await layout.homescreen_dialog(TR.buttons__enter_share, entered, needed)
 
 
-async def _show_remaining_groups_and_shares() -> None:
+def _get_remaining_groups_and_shares() -> "RemainingSharesInfo":
     """
-    Show info dialog for Slip39 Advanced - what shares are to be entered.
+    Prepare data for Slip39 Advanced - what shares are to be entered.
     """
     from trezor.crypto import slip39
 
     shares_remaining = storage_recovery.fetch_slip39_remaining_shares()
-    # should be stored at this point
-    assert shares_remaining
+    assert shares_remaining  # should be stored at this point
 
     groups = set()
     first_entered_index = -1
     for i, group_count in enumerate(shares_remaining):
         if group_count < slip39.MAX_SHARE_COUNT:
             first_entered_index = i
+            break
 
     share = None
     for index, remaining in enumerate(shares_remaining):
         if 0 <= remaining < slip39.MAX_SHARE_COUNT:
             m = storage_recovery_shares.fetch_group(index)[0]
             if not share:
                 share = slip39.decode_mnemonic(m)
-            identifier = m.split(" ")[0:3]
-            groups.add((remaining, tuple(identifier)))
+            identifier = tuple(m.split(" ")[0:3])
+            groups.add(identifier)
         elif remaining == slip39.MAX_SHARE_COUNT:  # no shares yet
-            identifier = storage_recovery_shares.fetch_group(first_entered_index)[
-                0
-            ].split(" ")[0:2]
-            groups.add((remaining, tuple(identifier)))
+            identifier = tuple(
+                storage_recovery_shares.fetch_group(first_entered_index)[0].split(" ")[
+                    0:2
+                ]
+            )
+            groups.add(identifier)
 
     assert share  # share needs to be set
-    return await layout.show_remaining_shares(
-        groups, shares_remaining, share.group_threshold
-    )
+    return groups, shares_remaining, share.group_threshold

core/src/apps/management/recovery_device/layout.py

@@ -6,16 +6,21 @@
     request_word_count,
     show_group_share_success,
     show_recovery_warning,
-    show_remaining_shares,
 )
 
 from apps.common import backup_types
 
 if TYPE_CHECKING:
-    from typing import Callable
+    from typing import List, Set, Tuple
 
     from trezor.enums import BackupType
 
+    # RemainingSharesInfo represents the data structure for remaining shares in SLIP-39 recovery:
+    # - Set of tuples, each containing 2 or 3 words identifying a group
+    # - List of remaining share counts for each group
+    # - Group threshold (minimum number of groups required)
+    RemainingSharesInfo = Tuple[Set[Tuple[str, ...]], List[int], int]
+
 
 async def request_mnemonic(
     word_count: int, backup_type: BackupType | None
@@ -123,8 +128,8 @@ async def homescreen_dialog(
     button_label: str,
     text: str,
     subtext: str | None = None,
-    info_func: Callable | None = None,
     show_info: bool = False,
+    remaining_shares_info: "RemainingSharesInfo | None" = None,
 ) -> None:
     import storage.recovery as storage_recovery
     from trezor.ui.layouts.recovery import continue_recovery
@@ -133,6 +138,11 @@ async def homescreen_dialog(
 
     recovery_type = storage_recovery.get_type()
     if not await continue_recovery(
-        button_label, text, subtext, info_func, recovery_type, show_info
+        button_label,
+        text,
+        subtext,
+        recovery_type,
+        show_info,
+        remaining_shares_info,
     ):
         raise RecoveryAborted

core/src/trezor/ui/layouts/mercury/recovery.py

@@ -1,4 +1,4 @@
-from typing import Callable, Iterable
+from typing import TYPE_CHECKING
 
 import trezorui2
 from trezor import TR
@@ -11,6 +11,9 @@
 CANCELLED = trezorui2.CANCELLED  # global_import_cache
 INFO = trezorui2.INFO  # global_import_cache
 
+if TYPE_CHECKING:
+    from apps.management.recovery_device.layout import RemainingSharesInfo
+
 
 async def request_word_count(recovery_type: RecoveryType) -> int:
     selector = RustLayout(trezorui2.select_word_count(recovery_type=recovery_type))
@@ -40,16 +43,18 @@ async def request_word(
     return word
 
 
-async def show_remaining_shares(
-    groups: Iterable[tuple[int, tuple[str, ...]]],  # remaining + list 3 words
-    shares_remaining: list[int],
-    group_threshold: int,
-) -> None:
+def format_remaining_shares_info(
+    remaining_shares_info: "RemainingSharesInfo",
+) -> list[tuple[str, str]]:
     from trezor import strings
     from trezor.crypto.slip39 import MAX_SHARE_COUNT
 
+    groups, shares_remaining, group_threshold = remaining_shares_info
+
     pages: list[tuple[str, str]] = []
-    for remaining, group in groups:
+    completed_groups = shares_remaining.count(0)
+
+    for group, remaining in zip(groups, shares_remaining):
         if 0 < remaining < MAX_SHARE_COUNT:
             title = strings.format_plural(
                 TR.recovery__x_more_items_starting_template_plural,
@@ -58,10 +63,8 @@ async def show_remaining_shares(
             )
             words = "\n".join(group)
             pages.append((title, words))
-        elif (
-            remaining == MAX_SHARE_COUNT and shares_remaining.count(0) < group_threshold
-        ):
-            groups_remaining = group_threshold - shares_remaining.count(0)
+        elif remaining == MAX_SHARE_COUNT and completed_groups < group_threshold:
+            groups_remaining = group_threshold - completed_groups
             title = strings.format_plural(
                 TR.recovery__x_more_items_starting_template_plural,
                 groups_remaining,
@@ -70,13 +73,7 @@ async def show_remaining_shares(
             words = "\n".join(group)
             pages.append((title, words))
 
-    await raise_if_not_confirmed(
-        interact(
-            RustLayout(trezorui2.show_remaining_shares(pages=pages)),
-            "show_shares",
-            ButtonRequestType.Other,
-        )
-    )
+    return pages
 
 
 async def show_group_share_success(share_index: int, group_index: int) -> None:
@@ -102,26 +99,25 @@ async def continue_recovery(
     button_label: str,  # unused on mercury
     text: str,
     subtext: str | None,
-    info_func: Callable | None,  # TODO: see below
     recovery_type: RecoveryType,
     show_info: bool = False,
+    remaining_shares_info: "RemainingSharesInfo | None" = None,
 ) -> bool:
-    # TODO: info_func should be changed to return data to be shown (and not show
-    # them) so that individual models can implement showing logic on their own.
-    # T3T1 should move the data to `flow_continue_recovery` and hide them
-    # in the context menu
-
     # NOTE: show_info can be understood as first screen before any shares
     # NOTE: button request sent from the flow
-    homepage = RustLayout(
+    result = await RustLayout(
         trezorui2.flow_continue_recovery(
             first_screen=show_info,
             recovery_type=recovery_type,
             text=text,
             subtext=subtext,
+            pages=(
+                format_remaining_shares_info(remaining_shares_info)
+                if remaining_shares_info
+                else None
+            ),
         )
     )
-    result = await homepage
     return result is CONFIRMED
 
 

core/src/trezor/ui/layouts/tr/recovery.py

@@ -1,4 +1,4 @@
-from typing import Callable, Iterable
+from typing import TYPE_CHECKING, Iterable
 
 import trezorui2
 from trezor import TR
@@ -7,6 +7,9 @@
 from ..common import interact
 from . import RustLayout, raise_if_not_confirmed, show_warning
 
+if TYPE_CHECKING:
+    from apps.management.recovery_device.layout import RemainingSharesInfo
+
 
 async def request_word_count(recovery_type: RecoveryType) -> int:
     count = await interact(
@@ -97,9 +100,9 @@ async def continue_recovery(
     button_label: str,
     text: str,
     subtext: str | None,
-    info_func: Callable | None,
     recovery_type: RecoveryType,
     show_info: bool = False,
+    remaining_shares_info: "RemainingSharesInfo | None" = None,  # unused on TR
 ) -> bool:
     # TODO: implement info_func?
     # There is very limited space on the screen