#!/usr/bin/env python3
"""NAVIGATION lane — Urik Keyboard (com.urik.keyboard).

Owns surface REACHABILITY + back-stack integrity: this lane is the sole owner of
jump_kind="reach" and of the depth>=2 chains. Every forward jump is proven with
and_reach(before, after, target, source): the TARGET surface's discriminating
element APPEARED and the SOURCE surface's DISAPPEARED. A screen that was already
in the tree was never reached. Every test opens its own entry point (the S0
launcher, via open_launcher()) and navigates FORWARD from there; back-navigation
is exercised as its own short forward-then-BACK test (nested cross-surface back()
chains are flaky).

Relaunching is only ever how a test re-establishes its S0 entry point — it is
NEVER the mechanism that reaches a destination. The reach is always a forward tap
proven by and_reach*, so restart lives in open_launcher()/open_settings(), one
level below the reach call.

Ground truth for every target/source string below was observed live on the
original app before the assertion was written (see recon.md + recon_shots/).

Two source-collision hazards were found live and encoded here:
  * The Privacy screen contains the summary "Save keyboard settings and custom
    key mappings...", so the substring "Keyboard Settings" does NOT vanish on the
    S2->Privacy jump — the source for that jump is a distinctive list row instead.
  * Several destination TOOLBAR titles equal their originating list-row text
    (Open Source Licenses / Dictionary Data / Customize Keys / Reset to Defaults),
    so those jumps assert a destination-only element (a content view id or a
    unique button/message), never the colliding title.
"""
import os, sys
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from android_testgen_kit import *  # noqa: F403

TESTS = []


def test(fn):
    TESTS.append(fn)
    return fn


# ── Shared helpers ──────────────────────────────────────────────────────────────

def open_launcher():
    """Re-establish this test's S0 (MainActivity launcher) entry point and return
    its fresh node list. Relaunch is the ISOLATION mechanism (kit contract: each
    test owns its entry point), never the navigation under test."""
    restart_app()
    wait_for_foreground()
    return ui()


def open_settings():
    """S0 -> SettingsActivity. Returns the fresh Settings node list, or None."""
    nodes = open_launcher()
    trig = find_node(nodes, text="Open Settings") or find_node_ci(nodes, "Open Settings")
    if not trig or not tap_node(trig):
        return None
    after = ui()
    # Confirm we are on the Settings list before any test navigates further.
    if find_node(after, text="Keyboard Settings") is None:
        return None
    return after


def theme_name_tv(nodes):
    """The dynamic theme-name TextView on S0 (reads 'Default'/'Abyss'/...). It is
    the only short TextView that is neither the app title nor a button label, so
    locate it structurally rather than by a value that persists across runs."""
    known = {"urik keyboard", "enable", "open settings", "about"}
    btnlabels = {b.get("text", "").strip().lower() for b in find_by_class(nodes, "Button")}
    for n in nodes:
        if not n.get("class", "").endswith("TextView"):
            continue
        t = n.get("text", "").strip()
        if t and t.lower() not in known and t.lower() not in btnlabels and len(t) < 20:
            return n
    return None


def tap_up(nodes):
    """Tap the toolbar up-affordance (ImageButton content-desc 'Navigate up') and
    settle for the surface transition. This IS the back action under test, so it
    presses BACK exactly once — callers must NOT also call and_back()."""
    up = find_node(nodes, content_desc="Navigate up")
    if not up or not tap_node(up):
        return False
    settle("tap")  # a fragment/activity pop can outlast the default tap settle
    return True


# Depth-family helpers. The and_enter_*/and_reach_* NAME is what the depth audit
# looks for; the implementation is ours. Each proves ONE surface crossing.

def and_enter_settings():
    """S0 -> Settings, proven (Keyboard Settings appeared, Open Settings gone)."""
    trig = find_node(open_launcher(), text="Open Settings")
    return bool(trig) and and_reach_surface(trig, "Keyboard Settings", "Open Settings")


def and_reach_appearance():
    """Settings -> Appearance, proven."""
    nodes = open_settings()
    if not nodes:
        return False
    row = find_node(nodes, text="Appearance")
    return bool(row) and and_reach_surface(row, "Key Press Highlight", "Keyboard Settings")


def and_reach_layout_input():
    """Settings -> Layout & Input, proven (row text is literally 'Layout &amp; Input')."""
    nodes = open_settings()
    if not nodes:
        return False
    row = find_node(nodes, text="Layout &amp; Input")
    return bool(row) and and_reach_surface(row, "Keyboard Layout", "Keyboard Settings")


# ══════════════════════════════════════════════════════════════════════════════
# (A) S0 top-level destinations — depth 1, reach
# ══════════════════════════════════════════════════════════════════════════════

@test
@and_test(expects=("nav_reach_settings", "nav_reach_settings_vlm"))
def test_reach_settings():
    nodes = open_launcher()
    trig = find_node(nodes, text="Open Settings") or find_node_ci(nodes, "Open Settings")
    ok = trig is not None and and_reach_surface(trig, "Keyboard Settings", "Open Settings")
    record("nav_reach_settings", ok,
           "" if ok else "feature_missing: Settings surface not reachable from 'Open Settings'",
           depth=1, jump_kind="reach",
           expect="'Keyboard Settings' title appeared; launcher 'Open Settings' button gone")
    vlm_assert("nav_reach_settings",
               "Is a settings screen showing a top toolbar with a left-pointing back "
               "arrow at the top-left and a vertical list of labelled rows below it?",
               RESULTS_DIR, tag="position")


@test
@and_test(expects=("nav_reach_about", "nav_reach_about_vlm"))
def test_reach_about():
    nodes = open_launcher()
    trig = find_node(nodes, text="About") or find_node_ci(nodes, "About")
    # Discriminator = About page text substring ('GNU GPL v3.0'), which is unique to
    # the About screen; the toolbar title 'About' collides with the launcher button.
    ok = trig is not None and and_reach_surface(trig, "GNU GPL v3.0", "Open Settings")
    record("nav_reach_about", ok,
           "" if ok else "feature_missing: About surface not reachable from 'About' button",
           depth=1, jump_kind="reach",
           expect="About text ('...GNU GPL v3.0...') appeared; launcher 'Open Settings' gone")
    vlm_assert("nav_reach_about",
               "Is this an 'About' text page: a screen filled mostly with lines of text "
               "(version, copyright, links) and NO keyboard preview or list of toggle rows?",
               RESULTS_DIR, tag="layout")


@test
@and_test(expects=("nav_reach_themepicker", "nav_reach_themepicker_vlm"))
def test_reach_themepicker():
    nodes = open_launcher()
    trig = theme_name_tv(nodes)
    ok = trig is not None and and_reach_surface(trig, "Keyboard Theme", "Open Settings")
    record("nav_reach_themepicker", ok,
           "" if ok else "feature_missing: ThemePicker not reachable from the theme-name card",
           depth=1, jump_kind="reach",
           expect="'Keyboard Theme' title appeared; launcher 'Open Settings' gone")
    vlm_assert("nav_reach_themepicker",
               "Does this screen show a vertical list of keyboard theme previews rendered "
               "in several DIFFERENT colors (e.g. a dark one, a white/light one, a black one)?",
               RESULTS_DIR, tag="color")


@test
@and_test(expects=("nav_reach_features_sheet", "nav_reach_features_sheet_vlm"))
def test_reach_features_sheet():
    nodes = open_launcher()
    fabs = find_by_class(nodes, "FloatingActionButton")
    trig = fabs[0] if fabs else None
    # The sheet slides over the launcher, so 'Open Settings' is covered (disappears)
    # while a tip string ('Learning Words') appears.
    ok = trig is not None and and_reach_surface(trig, "Learning Words", "Open Settings")
    record("nav_reach_features_sheet", ok,
           "" if ok else "feature_missing: Features bottom sheet not reachable from the FAB",
           depth=1, jump_kind="reach",
           expect="Features tip 'Learning Words' appeared; launcher 'Open Settings' covered/gone")
    vlm_assert("nav_reach_features_sheet",
               "Is a bottom sheet panel covering the lower portion of the screen, showing a "
               "list of tip titles with descriptions, while the top of the screen is dimmed?",
               RESULTS_DIR, tag="position")


# ══════════════════════════════════════════════════════════════════════════════
# (B) Settings -> each of the 8 rows — depth 2, reach (this lane's depth>=2 core)
# ══════════════════════════════════════════════════════════════════════════════

@test
@and_test(expects=("nav_settings_to_autocorrect",))
def test_settings_to_autocorrect():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_autocorrect", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Auto-Correct fragment after tapping its row")
        return
    and_enter("Settings")  # crossed S0 -> Settings
    row = find_node(nodes, text="Auto-Correct Settings")
    ok = row is not None and and_reach_surface(row, "Spell Check", "Keyboard Settings")
    record("nav_settings_to_autocorrect", ok,
           "" if ok else "feature_missing: Auto-Correct fragment not reachable from its row",
           depth=2, jump_kind="reach",
           expect="'Spell Check' row appeared; 'Keyboard Settings' title gone")


@test
@and_test(expects=("nav_settings_to_languages",))
def test_settings_to_languages():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_languages", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Languages fragment after tapping its row")
        return
    and_enter("Settings")
    row = find_node(nodes, text="Language Settings")
    ok = row is not None and and_reach_surface(row, "Merged Dictionaries", "Keyboard Settings")
    record("nav_settings_to_languages", ok,
           "" if ok else "feature_missing: Languages fragment not reachable from its row",
           depth=2, jump_kind="reach",
           expect="'Merged Dictionaries' row appeared; 'Keyboard Settings' title gone")


@test
@and_test(expects=("nav_settings_to_typing",))
def test_settings_to_typing():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_typing", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Typing Behavior fragment after tapping its row")
        return
    and_enter("Settings")
    row = find_node(nodes, text="Typing Behavior Settings")
    ok = row is not None and and_reach_surface(row, "Double-Space Period", "Keyboard Settings")
    record("nav_settings_to_typing", ok,
           "" if ok else "feature_missing: Typing Behavior fragment not reachable from its row",
           depth=2, jump_kind="reach",
           expect="'Double-Space Period' row appeared; 'Keyboard Settings' title gone")


@test
@and_test(expects=("nav_settings_to_layout",))
def test_settings_to_layout():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_layout", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Layout & Input fragment after tapping its row")
        return
    and_enter("Settings")
    # The dump keeps '&' un-unescaped: the row text is literally 'Layout &amp; Input'.
    row = find_node(nodes, text="Layout &amp; Input")
    ok = row is not None and and_reach_surface(row, "Keyboard Layout", "Keyboard Settings")
    record("nav_settings_to_layout", ok,
           "" if ok else "feature_missing: Layout & Input fragment not reachable from its row",
           depth=2, jump_kind="reach",
           expect="'Keyboard Layout' row appeared; 'Keyboard Settings' title gone")


@test
@and_test(expects=("nav_settings_to_appearance",))
def test_settings_to_appearance():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_appearance", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Appearance fragment after tapping its row")
        return
    and_enter("Settings")
    row = find_node(nodes, text="Appearance")
    ok = row is not None and and_reach_surface(row, "Key Press Highlight", "Keyboard Settings")
    record("nav_settings_to_appearance", ok,
           "" if ok else "feature_missing: Appearance fragment not reachable from its row",
           depth=2, jump_kind="reach",
           expect="'Key Press Highlight' row appeared; 'Keyboard Settings' title gone")


@test
@and_test(expects=("nav_settings_to_privacy",))
def test_settings_to_privacy():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_privacy", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Privacy & Data fragment after tapping its row")
        return
    and_enter("Settings")
    row = find_node(nodes, text="Privacy &amp; Data")
    # SOURCE note: the Privacy screen itself contains the Export-Settings summary
    # "Save keyboard settings and custom key mappings...", so the substring
    # "Keyboard Settings" SURVIVES the jump. Use a distinctive Settings-list row
    # ("Dictionary Data") that genuinely vanishes and has no substring collision.
    ok = row is not None and and_reach_surface(row, "Clipboard History", "Dictionary Data")
    record("nav_settings_to_privacy", ok,
           "" if ok else "feature_missing: Privacy & Data fragment not reachable from its row",
           depth=2, jump_kind="reach",
           expect="'Clipboard History' row appeared; Settings-list 'Dictionary Data' row gone")


@test
@and_test(expects=("nav_settings_to_licenses",))
def test_settings_to_licenses():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_licenses", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Open Source Licenses screen after tapping its row")
        return
    and_enter("Settings")
    row = find_node(nodes, text="Open Source Licenses")
    # The toolbar title equals the row text (same node_key), so use the licenses
    # content view (resource-id 'oss_licenses_text'), unique to the destination.
    ok = row is not None and and_reach_surface(row, "oss_licenses_text", "Dictionary Data")
    record("nav_settings_to_licenses", ok,
           "" if ok else "feature_missing: Open Source Licenses screen not reachable from its row",
           depth=2, jump_kind="reach",
           expect="licenses text view appeared; 'Dictionary Data' row gone")


@test
@and_test(expects=("nav_settings_to_dictionary",))
def test_settings_to_dictionary():
    nodes = open_settings()
    if nodes is None:
        record("nav_settings_to_dictionary", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Dictionary Data screen after tapping its row")
        return
    and_enter("Settings")
    row = find_node(nodes, text="Dictionary Data")
    # Title collides with the row; the attribution body text is unique to the screen.
    ok = row is not None and and_reach_surface(row, "DICTIONARY DATA ATTRIBUTION",
                                               "Open Source Licenses")
    record("nav_settings_to_dictionary", ok,
           "" if ok else "feature_missing: Dictionary Data screen not reachable from its row",
           depth=2, jump_kind="reach",
           expect="attribution text appeared; 'Open Source Licenses' row gone")


# ══════════════════════════════════════════════════════════════════════════════
# (C) Deep chains — and_enter per surface, prove the final reach
# ══════════════════════════════════════════════════════════════════════════════

@test
@and_test(expects=("nav_chain_appearance_themepicker", "nav_chain_appearance_themepicker_vlm"))
def test_chain_appearance_themepicker():
    """S0 -> Settings -> Appearance -> ThemePicker (depth 2 chain)."""
    nodes = open_settings()
    if nodes is None:
        record("nav_chain_appearance_themepicker", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="ThemePicker after Settings->Appearance->Theme")
        vlm_assert("nav_chain_appearance_themepicker",
                   "Does this screen show a vertical list of keyboard theme previews in "
                   "several different colors?", RESULTS_DIR, tag="color")
        return
    and_enter("Settings")  # S0 -> Settings
    appr = find_node(nodes, text="Appearance")
    hop1 = appr is not None and and_reach_surface(appr, "Key Press Highlight", "Keyboard Settings")
    hop2 = False
    if hop1:
        theme_row = find_node(ui(), text="Theme")
        hop2 = theme_row is not None and and_reach_surface(theme_row, "Keyboard Theme",
                                                           "Key Press Highlight")
    ok = hop1 and hop2
    record("nav_chain_appearance_themepicker", ok,
           "" if ok else "behavior_wrong: Appearance->Theme did not reach the ThemePicker",
           depth=2, jump_kind="reach",
           expect="'Keyboard Theme' appeared after the Appearance 'Theme' row; "
                  "'Key Press Highlight' gone")
    vlm_assert("nav_chain_appearance_themepicker",
               "Does this screen show a vertical list of keyboard theme previews rendered "
               "in several DIFFERENT colors (dark, light/white, black, etc.)?",
               RESULTS_DIR, tag="color")


@test
@and_test(expects=("nav_chain_layout_mapper", "nav_chain_layout_mapper_vlm"))
def test_chain_layout_mapper():
    """S0 -> Settings -> Layout & Input -> LayoutMapper (depth 3 chain)."""
    nodes = open_settings()
    if nodes is None:
        record("nav_chain_layout_mapper", False,
               "setup_failed: could not reach the Settings list", depth=3, jump_kind="reach",
               expect="LayoutMapper after Settings->Layout->Customize Keys")
        vlm_assert("nav_chain_layout_mapper",
                   "Does this screen show a full rendered QWERTY keyboard (rows of letter "
                   "keys) with a button below it?", RESULTS_DIR, tag="layout")
        return
    and_enter("Settings")  # S0 -> Settings
    li = find_node(nodes, text="Layout &amp; Input")
    hop1 = li is not None and and_reach_surface(li, "Keyboard Layout", "Keyboard Settings")
    hop2 = False
    if hop1:
        ck = find_node(ui(), text="Customize Keys")
        # LayoutMapper title 'Customize Keys' collides with the row; 'Reset All'
        # (a button unique to the mapper) is the discriminator.
        hop2 = ck is not None and and_reach_surface(ck, "Reset All", "Keyboard Layout")
    ok = hop1 and hop2
    record("nav_chain_layout_mapper", ok,
           "" if ok else "behavior_wrong: Layout->Customize Keys did not reach the LayoutMapper",
           depth=3, jump_kind="reach",
           expect="'Reset All' appeared after the 'Customize Keys' row; 'Keyboard Layout' gone")
    vlm_assert("nav_chain_layout_mapper",
               "Is a full keyboard laid out as horizontal rows of keys (number row, then "
               "letter rows Q-P, A-L, Z-M) rendered in the center of this screen?",
               RESULTS_DIR, tag="layout")


# ══════════════════════════════════════════════════════════════════════════════
# (D) Dialog reachability + dismissal (a dialog is a surface)
# ══════════════════════════════════════════════════════════════════════════════

@test
@and_test(expects=("nav_reset_dialog_reach", "nav_reset_dialog_reach_vlm"))
def test_reset_dialog_reach():
    """Privacy -> Reset to Defaults -> the confirm dialog appears (SAFE: never tap OK)."""
    nodes = open_settings()
    if nodes is None:
        record("nav_reset_dialog_reach", False,
               "setup_failed: could not reach the Settings list", depth=3, jump_kind="reach",
               expect="Reset confirm dialog after tapping 'Reset to Defaults'")
        vlm_assert("nav_reset_dialog_reach",
                   "Is a small modal dialog box centered over a dimmed screen, with two text "
                   "buttons in its bottom-right?", RESULTS_DIR, tag="position")
        return
    and_enter("Settings")
    pv = find_node(nodes, text="Privacy &amp; Data")
    # Privacy hop source: distinctive list row (see nav_settings_to_privacy note).
    hop1 = pv is not None and and_reach_surface(pv, "Clipboard History", "Dictionary Data")
    hop2 = False
    if hop1:
        reset = find_node(ui(), text="Reset to Defaults")
        # Title 'Reset to Defaults' collides with the row; the dialog MESSAGE is unique.
        hop2 = reset is not None and and_reach_surface(reset, "Reset all settings to defaults?",
                                                       "Clipboard History")
    ok = hop1 and hop2
    record("nav_reset_dialog_reach", ok,
           "" if ok else "behavior_wrong: 'Reset to Defaults' did not raise a confirm dialog",
           depth=3, jump_kind="reach",
           expect="dialog message 'Reset all settings to defaults?' appeared; "
                  "'Clipboard History' row covered/gone")
    vlm_assert("nav_reset_dialog_reach",
               "Is a small modal dialog box centered on the screen (with a title, a short "
               "message, and Cancel/OK buttons) over a dimmed background?",
               RESULTS_DIR, tag="position")


@test
@and_test(expects=("nav_reset_dialog_cancel",))
def test_reset_dialog_cancel():
    """Reset dialog -> Cancel -> dialog gone, back on Privacy (SAFE)."""
    nodes = open_settings()
    if nodes is None:
        record("nav_reset_dialog_cancel", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Privacy screen restored after Cancel")
        return
    and_enter("Settings")
    pv = find_node(nodes, text="Privacy &amp; Data")
    ok_pv = pv is not None and and_reach_surface(pv, "Clipboard History", "Dictionary Data")
    dismissed = False
    if ok_pv:
        reset = find_node(ui(), text="Reset to Defaults")
        if reset and and_reach_surface(reset, "Reset all settings to defaults?", "Clipboard History"):
            dlg = ui()
            cancel = find_node(dlg, text="Cancel")  # SAFETY: only ever Cancel, never OK
            before = and_showing(dlg)
            if cancel and tap_node(cancel):
                settle("tap")
                dismissed = and_reach(before, and_showing(),
                                      "Clipboard History", "Reset all settings to defaults?")
    record("nav_reset_dialog_cancel", ok_pv and dismissed,
           "" if (ok_pv and dismissed) else
           "behavior_wrong: Cancel did not dismiss the reset dialog back to Privacy",
           depth=2, jump_kind="reach",
           expect="after Cancel: dialog message gone, 'Clipboard History' row restored")


@test
@and_test(expects=("nav_suggestion_dialog_reach", "nav_suggestion_dialog_reach_vlm"))
def test_suggestion_dialog_reach():
    """Auto-Correct -> Suggestion Count -> the list dialog appears."""
    nodes = open_settings()
    if nodes is None:
        record("nav_suggestion_dialog_reach", False,
               "setup_failed: could not reach the Settings list", depth=3, jump_kind="reach",
               expect="Suggestion Count list dialog")
        vlm_assert("nav_suggestion_dialog_reach",
                   "Is a modal dialog showing a short vertical list of selectable options "
                   "each with a round radio button on its left?", RESULTS_DIR, tag="shape")
        return
    and_enter("Settings")
    ac = find_node(nodes, text="Auto-Correct Settings")
    hop1 = ac is not None and and_reach_surface(ac, "Spell Check", "Keyboard Settings")
    hop2 = False
    if hop1:
        sc = find_node(ui(), text="Suggestion Count")
        # The list dialog adds a select list; 'Learn New Words' (a row below in the
        # fragment) is covered by the dialog.
        hop2 = sc is not None and and_reach_surface(sc, "select_dialog_listview", "Learn New Words")
    ok = hop1 and hop2
    record("nav_suggestion_dialog_reach", ok,
           "" if ok else "behavior_wrong: 'Suggestion Count' did not open a list dialog",
           depth=3, jump_kind="reach",
           expect="dialog list ('select_dialog_listview') appeared; 'Learn New Words' covered/gone")
    vlm_assert("nav_suggestion_dialog_reach",
               "Is a modal dialog showing a short vertical list of numeric options, each with "
               "a round radio-button circle to its left, and a Cancel button?",
               RESULTS_DIR, tag="shape")


@test
@and_test(expects=("nav_suggestion_dialog_cancel",))
def test_suggestion_dialog_cancel():
    """Suggestion Count dialog -> Cancel -> back on the Auto-Correct fragment."""
    nodes = open_settings()
    if nodes is None:
        record("nav_suggestion_dialog_cancel", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Auto-Correct fragment restored after Cancel")
        return
    and_enter("Settings")
    ac = find_node(nodes, text="Auto-Correct Settings")
    ok_ac = ac is not None and and_reach_surface(ac, "Spell Check", "Keyboard Settings")
    dismissed = False
    if ok_ac:
        sc = find_node(ui(), text="Suggestion Count")
        if sc and and_reach_surface(sc, "select_dialog_listview", "Learn New Words"):
            dlg = ui()
            cancel = find_node(dlg, text="Cancel")
            before = and_showing(dlg)
            if cancel and tap_node(cancel):
                settle("tap")
                dismissed = and_reach(before, and_showing(),
                                      "Learn New Words", "select_dialog_listview")
    record("nav_suggestion_dialog_cancel", ok_ac and dismissed,
           "" if (ok_ac and dismissed) else
           "behavior_wrong: Cancel did not dismiss the Suggestion Count dialog",
           depth=2, jump_kind="reach",
           expect="after Cancel: dialog list gone, 'Learn New Words' row restored")


# ══════════════════════════════════════════════════════════════════════════════
# (E) Back-stack integrity — forward-then-BACK, proven in reverse with and_reach.
# The trigger under test (up-affordance / BACK) presses BACK exactly ONCE; these
# tests never double-pop.
# ══════════════════════════════════════════════════════════════════════════════

@test
@and_test(expects=("nav_backstack_up_autocorrect", "nav_backstack_up_autocorrect_vlm"))
def test_backstack_up_autocorrect():
    """Settings -> Auto-Correct, then the toolbar up-affordance returns to the list."""
    nodes = open_settings()
    if nodes is None:
        record("nav_backstack_up_autocorrect", False,
               "setup_failed: could not reach the Settings list", depth=1, jump_kind="reach",
               expect="Settings list restored after Navigate up")
        vlm_assert("nav_backstack_up_autocorrect",
                   "Does the toolbar at the top of this screen show a left-pointing back "
                   "arrow (up affordance) at its far left?", RESULTS_DIR, tag="shape")
        return
    and_enter("Settings")
    ac = find_node(nodes, text="Auto-Correct Settings")
    forward = ac is not None and and_reach_surface(ac, "Spell Check", "Keyboard Settings")
    sub = ui() if forward else []
    # VLM on the SUB-fragment: the up affordance must be present there. Captured
    # BEFORE we pop so the screenshot is of the sub-screen toolbar.
    vlm_assert("nav_backstack_up_autocorrect",
               "Does the toolbar at the very top of this screen show a left-pointing back "
               "arrow at its far left, next to the screen title?",
               RESULTS_DIR, tag="shape")
    returned = False
    if forward:
        before = and_showing(sub)
        if tap_up(sub):  # the up-affordance IS the back action; single BACK
            returned = and_reach(before, and_showing(), "Keyboard Settings", "Spell Check")
    record("nav_backstack_up_autocorrect", forward and returned,
           "" if (forward and returned) else
           "behavior_wrong: the up-affordance did not return to the Settings list",
           depth=1, jump_kind="reach",
           expect="'Keyboard Settings' title reappeared; 'Spell Check' row gone")


@test
@and_test(expects=("nav_backstack_about_to_home",))
def test_backstack_about_to_home():
    """S0 -> About, then BACK returns to the launcher."""
    trig = find_node(open_launcher(), text="About")
    forward = trig is not None and and_reach_surface(trig, "GNU GPL v3.0", "Open Settings")
    returned = False
    if forward:
        before = and_showing()
        and_back()  # BACK pops the About activity (single press)
        settle("tap")
        returned = and_reach(before, and_showing(), "Open Settings", "GNU GPL v3.0")
    record("nav_backstack_about_to_home", forward and returned,
           "" if (forward and returned) else
           "behavior_wrong: BACK from About did not return to the launcher",
           depth=1, jump_kind="reach",
           expect="launcher 'Open Settings' button restored; About text ('GNU GPL v3.0') gone")


@test
@and_test(expects=("nav_backstack_themepicker_to_home",))
def test_backstack_themepicker_to_home():
    """S0 -> ThemePicker (card), then BACK returns to the launcher."""
    trig = theme_name_tv(open_launcher())
    forward = trig is not None and and_reach_surface(trig, "Keyboard Theme", "Open Settings")
    returned = False
    if forward:
        before = and_showing()
        and_back()  # BACK pops the ThemePicker activity (single press)
        settle("tap")
        returned = and_reach(before, and_showing(), "Open Settings", "Keyboard Theme")
    record("nav_backstack_themepicker_to_home", forward and returned,
           "" if (forward and returned) else
           "behavior_wrong: BACK from ThemePicker did not return to the launcher",
           depth=1, jump_kind="reach",
           expect="launcher 'Open Settings' button restored; 'Keyboard Theme' title gone")


@test
@and_test(expects=("nav_backstack_2hop_unwind",))
def test_backstack_2hop_unwind():
    """Depth-2 chain unwound hop by hop: S0->Settings->Appearance->ThemePicker,
    then the up-affordance TWICE, asserting the expected surface after each pop."""
    nodes = open_settings()
    if nodes is None:
        record("nav_backstack_2hop_unwind", False,
               "setup_failed: could not reach the Settings list", depth=2, jump_kind="reach",
               expect="Settings restored after unwinding ThemePicker->Appearance->Settings")
        return
    and_enter("Settings")  # S0 -> Settings
    appr = find_node(nodes, text="Appearance")
    hop1 = appr is not None and and_reach_surface(appr, "Key Press Highlight", "Keyboard Settings")
    hop2 = False
    if hop1:
        theme_row = find_node(ui(), text="Theme")
        hop2 = theme_row is not None and and_reach_surface(theme_row, "Keyboard Theme",
                                                           "Key Press Highlight")
    pop1 = pop2 = False
    if hop2:
        tp = ui()
        b_tp = and_showing(tp)
        if tap_up(tp):  # pop ThemePicker -> Appearance (single BACK)
            pop1 = and_reach(b_tp, and_showing(), "Key Press Highlight", "Keyboard Theme")
        if pop1:
            appr_now = ui()
            b_appr = and_showing(appr_now)
            if tap_up(appr_now):  # pop Appearance -> Settings (single BACK)
                pop2 = and_reach(b_appr, and_showing(), "Keyboard Settings", "Key Press Highlight")
    ok = hop1 and hop2 and pop1 and pop2
    record("nav_backstack_2hop_unwind", ok,
           "" if ok else "behavior_wrong: BACK did not unwind ThemePicker->Appearance->Settings hop by hop",
           depth=2, jump_kind="reach",
           expect="pop1 -> Appearance ('Key Press Highlight'), pop2 -> Settings ('Keyboard Settings')")


if __name__ == "__main__":
    run_suite(TESTS, "navigation")