//nolint:testpackage // white-box tests reach unexported state (approved 2026-07-07)
package game

import (
	"encoding/gob"
	"errors"
	"os"
	"path/filepath"
	"slices"
	"strconv"
	"testing"
)

// mustNotPanic runs fn and turns a panic into an ordinary test failure.
// The bug these tests cover (issue #10) panicked out of an array index,
// and an unrecovered panic would take the whole test binary down instead
// of reporting which dispatch regressed.
func mustNotPanic(t *testing.T, what string, fn func()) {
	t.Helper()

	defer func() {
		if r := recover(); r != nil {
			t.Errorf("%s panicked: %v", what, r)
		}
	}()

	fn()
}

// TestCreateObjWandFReproducer is the exact reported crash: wizard mode,
// C, '/' for a wand, 'f' for which. 'f' is nibble 15 and there are only
// NumWandTypes (14) wands, so fixStick used to index two past the end of
// ws_type[] and panic.
func TestCreateObjWandFReproducer(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	g.Wizard = true
	before := len(g.Player.Pack)

	setInput(t, g, '/', 'f')

	mustNotPanic(t, "createObj with wand 'f'", g.createObj)

	if len(g.Player.Pack) != before {
		t.Errorf("out-of-range wand was added to the pack: %d items, want %d",
			len(g.Player.Pack), before)
	}
}

// TestCreateObjRejectsOutOfRangeWhich sweeps the rejection across every
// kind whose Which is a table index, including input outside '0'-'f'.
// isDigit is false for such input, so it takes the letter branch, where
// ch-'a' is byte arithmetic and wraps rather than going negative: 'A'
// (65) gives int(224)+10 == 234 and '!' (33) gives int(192)+10 == 202.
// Those far-past-the-end values, not negative ones, are what the guard
// has to catch on the keyboard path.
func TestCreateObjRejectsOutOfRangeWhich(t *testing.T) {
	t.Parallel()

	cases := []struct {
		name  string
		typ   byte
		which byte
	}{
		{"wand f is past NumWandTypes", Stick, 'f'},
		{"potion f is past NumPotionTypes", Potion, 'f'},
		{"ring f is past NumRingTypes", Ring, 'f'},
		// NumScrollTypes is 18, past the 'f' the prompt tops out at, so a
		// scroll can only be driven out of range by input that wraps.
		{"scroll 'A' wraps to 234", Scroll, 'A'},
		{"armor 9 is past NumArmorTypes", Armor, '9'},
		{"weapon 9 is the flame pseudo-weapon", Weapon, '9'},
		{"wand 'A' wraps to 234", Stick, 'A'},
		{"wand '!' wraps to 202", Stick, '!'},
		{"armor 'A' wraps to 234", Armor, 'A'},
		{"weapon '!' wraps to 202", Weapon, '!'},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			g := mkGameInput(t)
			g.Wizard = true
			before := len(g.Player.Pack)

			setInput(t, g, tc.typ, tc.which)

			mustNotPanic(t, tc.name, g.createObj)

			if len(g.Player.Pack) != before {
				t.Errorf("pack grew to %d items, want %d: a rejected item was created",
					len(g.Player.Pack), before)
			}
		})
	}
}

// TestCreateObjAcceptsValidWhich pins the other half of the contract: the
// bounds check must not touch any in-range choice.
func TestCreateObjAcceptsValidWhich(t *testing.T) {
	t.Parallel()

	cases := []struct {
		name  string
		typ   byte
		which byte
		kind  ObjectKind
		want  int
	}{
		{"wand of light", Stick, '0', KindWand, int(WandLight)},
		{"potion 0", Potion, '0', KindPotion, int(PotionConfusion)},
		{"scroll 9", Scroll, '9', KindScroll, int(ScrollIdentifyRingOrStick)},
		{"ring d, the last ring", Ring, 'd', KindRing, int(NumRingTypes) - 1},
		{"armor 7, the last armor", Armor, '7', KindArmor, int(NumArmorTypes) - 1},
		{"weapon 8, the last real weapon", Weapon, '8', KindWeapon, int(WeaponSpear)},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			g := mkGameInput(t)
			g.Wizard = true

			before := make(map[*Object]bool, len(g.Player.Pack))
			for _, o := range g.Player.Pack {
				before[o] = true
			}

			// The armor and weapon arms read one more character for the
			// blessing prompt; 'n' means neither cursed nor blessed.
			setInput(t, g, tc.typ, tc.which, 'n')
			g.createObj()

			if len(g.Player.Pack) != len(before)+1 {
				t.Fatalf("pack has %d items, want %d: valid item not created",
					len(g.Player.Pack), len(before)+1)
			}

			// addPack files the new item in kind order, so find it by
			// identity rather than assuming it landed at the end.
			var made *Object

			for _, o := range g.Player.Pack {
				if !before[o] {
					made = o
				}
			}

			if made.Kind != tc.kind || made.Which != tc.want {
				t.Errorf("created %v which %d, want %v which %d",
					made.Kind, made.Which, tc.kind, tc.want)
			}
		})
	}
}

// TestCreateObjKeepsRNGSequence proves the guard costs no RNG draws: a
// rejected creation must leave the generator exactly where it was, or
// every later roll in the game would shift.
func TestCreateObjKeepsRNGSequence(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	g.Wizard = true
	before := g.Rng.Seed

	setInput(t, g, Stick, 'f')
	g.createObj()

	if g.Rng.Seed != before {
		t.Errorf("rejected creation consumed RNG: seed %d, want %d",
			g.Rng.Seed, before)
	}
}

// malformed builds an object of the given kind whose Which sits one past
// the end of that kind's table — the state the wizard bug used to leave
// behind, and the state a corrupt save file could still describe.
func malformed(kind ObjectKind) *Object {
	obj := newObject()
	obj.Kind = kind
	obj.Which = whichLimit(kind)
	obj.Count = 1

	return obj
}

// TestZapMalformedWandDoesNotPanic covers the sticks.go dispatch. C's
// do_zap matched no case and still ran o_charges--, so the charge must be
// spent even though the zap did nothing. What it says while doing nothing
// belongs to TestZapUnhandledWandSaysBizarreSchtick.
func TestZapMalformedWandDoesNotPanic(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	wand := malformed(KindWand)
	wand.Charges = 3
	ch := give(g, wand)

	setInput(t, g, ch)

	mustNotPanic(t, "doZap on a malformed wand", g.doZap)

	if wand.Charges != 2 {
		t.Errorf("charges = %d after zapping, want 2", wand.Charges)
	}
}

// TestQuaffMalformedPotionDoesNotPanic covers the potions.go dispatch and
// the callIt lookup that follows it.
func TestQuaffMalformedPotionDoesNotPanic(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	before := len(g.Player.Pack)
	ch := give(g, malformed(KindPotion))

	setInput(t, g, ch)

	mustNotPanic(t, "quaff of a malformed potion", g.quaff)

	if len(g.Player.Pack) != before {
		t.Errorf("pack has %d items, want %d: the potion was not consumed",
			len(g.Player.Pack), before)
	}
}

// TestReadMalformedScrollDoesNotPanic covers the scrolls.go dispatch and
// its callIt lookup.
func TestReadMalformedScrollDoesNotPanic(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	before := len(g.Player.Pack)
	ch := give(g, malformed(KindScroll))

	setInput(t, g, ch)

	mustNotPanic(t, "readScroll of a malformed scroll", g.readScroll)

	if len(g.Player.Pack) != before {
		t.Errorf("pack has %d items, want %d: the scroll was not consumed",
			len(g.Player.Pack), before)
	}
}

// TestMalformedArmorDoesNotPanic covers the a_class[] reads: pricing at
// death, the identified-armor name, and the detect-magic test.
func TestMalformedArmorDoesNotPanic(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	armor := malformed(KindArmor)
	armor.Flags.Set(Known)

	mustNotPanic(t, "naming a malformed suit of armor", func() {
		if got := g.inventoryName(armor, false); got != armor.Kind.String() {
			t.Errorf("inventoryName = %q, want %q", got, armor.Kind.String())
		}
	})

	mustNotPanic(t, "isMagic on a malformed suit of armor", func() {
		g.isMagic(armor)
	})

	mustNotPanic(t, "appraising a malformed suit of armor", func() {
		if worth := g.objectWorth(armor); worth != 0 {
			t.Errorf("objectWorth = %d, want 0", worth)
		}
	})

	if got := g.data.armorClass(armor.Which); got != 0 {
		t.Errorf("armorClass(%d) = %d, want 0", armor.Which, got)
	}
}

// TestMalformedWeaponDoesNotPanic covers the init_dam[] read. WeaponFlame
// is the first kind with no table row, so initWeapon must leave the
// object alone rather than index past the end.
func TestMalformedWeaponDoesNotPanic(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	weap := newObject()

	mustNotPanic(t, "initWeapon with the flame pseudo-weapon", func() {
		g.initWeapon(weap, WeaponFlame)
	})

	mustNotPanic(t, "initWeapon with a negative weapon kind", func() {
		g.initWeapon(weap, WeaponKind(-1))
	})

	if weap.Kind != KindNone {
		t.Errorf("weapon was initialized from a missing table row: kind %v",
			weap.Kind)
	}
}

// TestFixStickMalformedWhichDoesNotPanic covers the ws_type[] read that
// the reported reproducer actually crashed on.
func TestFixStickMalformedWhichDoesNotPanic(t *testing.T) {
	t.Parallel()

	g := mkGameInput(t)
	wand := malformed(KindWand)

	mustNotPanic(t, "fixStick on a malformed wand", func() {
		g.fixStick(wand)
	})

	if wand.Damage.String() != "1x1" {
		t.Errorf("damage = %q, want the wand damage %q",
			wand.Damage.String(), "1x1")
	}
}

// TestRestoreRejectsOutOfRangeWhich is the save-file half of the fix: a
// malformed object must not be able to sneak past the keyboard guard by
// arriving in a snapshot.
//
// A decoded save is also the only place a *negative* Which can come
// from. On the keyboard path createObj's ch-'a' is byte arithmetic and
// wraps, so 'A' and '!' land at 234 and 202; Which is a plain int in the
// gob stream, so a tampered file can carry any value at all. Both shapes
// are covered here, and the negative case is what exercises the
// Which >= 0 arm of hasValidWhich.
func TestRestoreRejectsOutOfRangeWhich(t *testing.T) {
	t.Parallel()

	cases := []struct {
		name  string
		which int
	}{
		{"one past the wand table", int(NumWandTypes)},
		{"the value 'A' wraps to on the keyboard path", 234},
		{"the value '!' wraps to on the keyboard path", 202},
		{"negative, reachable only from a tampered file", -1},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			g := mkGame(t, 11)
			st := g.snapshot()

			if len(st.Player.Body.Pack) == 0 {
				t.Fatal("starting pack is empty; nothing to corrupt")
			}

			st.Player.Body.Pack[0].Kind = KindWand
			st.Player.Body.Pack[0].Which = tc.which

			path := filepath.Join(t.TempDir(), "rogue.save")
			writeSnapshot(t, path, st)

			_, restoreErr := Restore(path, Params{Term: &testTerm{}})
			if !errors.Is(restoreErr, ErrSaveCorrupt) {
				t.Errorf("Restore error = %v, want ErrSaveCorrupt", restoreErr)
			}

			_, statErr := os.Stat(path)
			if statErr != nil {
				t.Error("a rejected save file was deleted; it should be left alone")
			}
		})
	}
}

// writeSnapshot gob-encodes a snapshot to path the way saveFile does.
func writeSnapshot(t *testing.T, path string, st *SaveState) {
	t.Helper()

	f, err := os.Create(path) //nolint:gosec // G304: test temp path
	if err != nil {
		t.Fatal(err)
	}

	encErr := gob.NewEncoder(f).Encode(st)
	if encErr != nil {
		t.Fatal(encErr)
	}

	closeErr := f.Close()
	if closeErr != nil {
		t.Fatal(closeErr)
	}
}

// TestWhichLimitCoversEveryIndexedTable pins the bounds table itself
// against the per-kind arrays it has to agree with.
func TestWhichLimitCoversEveryIndexedTable(t *testing.T) {
	t.Parallel()

	// len() of an array field is a compile-time constant, so the zero
	// value is enough to read the table sizes off.
	var it ItemLore

	cases := []struct {
		kind ObjectKind
		size int
	}{
		{KindPotion, len(it.Potions)},
		{KindScroll, len(it.Scrolls)},
		{KindRing, len(it.Rings)},
		{KindWand, len(it.Sticks)},
		{KindArmor, len(it.Armors)},
		{KindWeapon, len(it.Weapons)},
	}

	for _, tc := range cases {
		if got := whichLimit(tc.kind); got != tc.size {
			t.Errorf("whichLimit(%v) = %d, want the table size %d",
				tc.kind, got, tc.size)
		}
	}

	// Kinds whose Which is not a table index accept anything, as in C.
	for _, kind := range []ObjectKind{KindFood, KindAmulet, KindGold, KindNone} {
		obj := &Object{Kind: kind, Which: 99}
		if !obj.hasValidWhich() {
			t.Errorf("%v should not be bounds-checked on Which", kind)
		}
	}
}

// TestWizardToggleOffRehidesSensedMonsters drives '+' through command
// dispatch in wizard mode (command.c 317-338). Clearing the flag is the
// cheap half; the substantive half is turn_see(TRUE) — leaving wizard
// mode has to put the screen back, or there is no way out of wizard
// sight once it is on.
func TestWizardToggleOffRehidesSensedMonsters(t *testing.T) {
	t.Parallel()

	g := mkGame(t, 11)
	g.Wizard = true

	// A phantom carries ISINVIS straight from the monster table, so
	// seeMonst is false for it and it is on screen only because wizard
	// sight put it there.
	tp := spawnAdjacent(g, 'P')
	if !tp.On(Invisible) {
		t.Fatal("phantom is not invisible; this test needs an unseeable monster")
	}

	if g.seeMonst(tp) {
		t.Fatal("monster is ordinarily visible; wizard sight would reveal nothing")
	}

	if tp.OldCh == tp.Type {
		t.Fatalf("map char under the monster is also %q; the redraw "+
			"assertion would prove nothing", tp.Type)
	}

	g.turnSee(false)

	if !g.Player.On(SenseMonsters) {
		t.Fatal("turnSee(false) did not set SenseMonsters")
	}

	if ch := g.mvinch(tp.Pos.Y, tp.Pos.X); ch != tp.Type {
		t.Fatalf("wizard sight did not draw the monster: cell is %q, want %q",
			ch, tp.Type)
	}

	if !g.scr.Std.at(tp.Pos.Y, tp.Pos.X).standout {
		t.Fatal("wizard-sighted monster was not drawn in standout")
	}

	g.Msgs.Mpos = 0
	g.After = true

	g.dispatch('+')

	if g.Wizard {
		t.Error("'+' did not clear the wizard flag")
	}

	if g.Player.On(SenseMonsters) {
		t.Error("'+' left SenseMonsters set: turn_see(TRUE) was not performed")
	}

	if ch := g.mvinch(tp.Pos.Y, tp.Pos.X); ch != tp.OldCh {
		t.Errorf("monster still on screen after leaving wizard mode: cell is "+
			"%q, want the map char under it, %q", ch, tp.OldCh)
	}

	if g.scr.Std.at(tp.Pos.Y, tp.Pos.X).standout {
		t.Error("cell left in standout after leaving wizard mode")
	}

	if g.Msgs.Huh != "not wizard any more" {
		t.Errorf("message = %q, want %q", g.Msgs.Huh, "not wizard any more")
	}

	if g.After {
		t.Error("'+' consumed a turn; C sets after = FALSE")
	}
}

// TestWizardToggleWithoutWizardSaysSorry pins the other arm. C ran
// wizard = passwd() and said "sorry" when the answer was wrong; the
// password machinery is dropped, so that is the only outcome left. What
// it must not be any more is "illegal command '+'".
func TestWizardToggleWithoutWizardSaysSorry(t *testing.T) {
	t.Parallel()

	g := mkGame(t, 12)
	g.Wizard = false
	g.Msgs.Mpos = 0
	g.After = true

	g.dispatch('+')

	if g.Wizard {
		t.Error("'+' entered wizard mode with no password check to pass")
	}

	if g.Player.On(SenseMonsters) {
		t.Error("'+' turned on monster sense outside wizard mode")
	}

	if g.Msgs.Huh != "sorry" {
		t.Errorf("message = %q, want %q", g.Msgs.Huh, "sorry")
	}

	if g.After {
		t.Error("'+' consumed a turn; C sets after = FALSE")
	}
}

// The rest of this file covers game/wizard.go proper (issue #7). Every
// expected value below is transcribed from origin/c-master — wizard.c for
// create_obj/whatis/set_know/teleport/show_map, command.c for the CTRL('I')
// kit, extern.c for a_class[], weapons.c for init_dam[], and rogue.h for
// the R_* numbering and the F_* place flags — never from what the port
// happens to return.
//
// Two shapes recur. Scripted input always ends with an abort tail (a space
// for a --More--, then ESCAPE), because testTerm.ReadChar hands out filler
// forever once the script runs dry and a re-prompting loop would spin to
// the suite timeout instead of failing. And where C issues no prompt at
// all, the test asserts on the scripted input cursor rather than on state:
// a stray readchar would eat the next answer and desynchronise everything
// after it, which no state assertion would notice.

// mkWizard builds a headless game in wizard mode the way the program does.
// cmd/rogue/main.go turns ROGUE_WIZARD into Params.Wizard and New consumes
// that field, so no test here pokes g.Wizard. depth is what decides
// whether the generator produces secret (non-F_REAL) squares at all.
func mkWizard(t *testing.T, seed int32, depth int) *RogueGame {
	t.Helper()

	g := New(Params{Seed: seed, Wizard: true, Term: &testTerm{}})
	if !g.Wizard {
		t.Fatal("Params.Wizard did not turn on wizard mode")
	}

	g.Depth = depth
	g.NewLevel()
	g.Oldpos = g.Player.Pos
	g.Oldrp = g.roomIn(g.Player.Pos)

	return g
}

// packSet snapshots pack membership by identity. add_pack files a new item
// in kind order, so its position is no guide to which one it is.
func packSet(g *RogueGame) map[*Object]bool {
	seen := make(map[*Object]bool, len(g.Player.Pack))
	for _, o := range g.Player.Pack {
		seen[o] = true
	}

	return seen
}

// onlyNewItem returns the single object added to the pack since before.
func onlyNewItem(t *testing.T, g *RogueGame, before map[*Object]bool) *Object {
	t.Helper()

	var made []*Object

	for _, o := range g.Player.Pack {
		if !before[o] {
			made = append(made, o)
		}
	}

	if len(made) != 1 {
		t.Fatalf("pack gained %d objects, want exactly 1", len(made))
	}

	return made[0]
}

// inputUsed reports how many scripted keys have been consumed so far.
func inputUsed(t *testing.T, g *RogueGame) int {
	t.Helper()

	tt, ok := g.scr.term.(*testTerm)
	if !ok {
		t.Fatal("game terminal is not a testTerm")
	}

	return tt.pos
}

// TestCreateObjFilesTheItemInThePack covers the tail every arm of
// wizard.c create_obj shares: o_group = 0, o_count = 1, then
// add_pack(obj, FALSE). A potion is the kind C's switch does nothing for,
// so nothing else is in the way.
func TestCreateObjFilesTheItemInThePack(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 21, 1)
	before := packSet(g)

	setInput(t, g, Potion, '0', ' ', Escape)
	g.createObj()

	made := onlyNewItem(t, g, before)

	if made.Kind != KindPotion || made.Which != int(PotionConfusion) {
		t.Fatalf("created %v which %d, want %v which %d",
			made.Kind, made.Which, KindPotion, int(PotionConfusion))
	}

	if made.Count != 1 {
		t.Errorf("count = %d, want the 1 C sets", made.Count)
	}

	if made.Group != 0 {
		t.Errorf("group = %d, want the 0 C sets", made.Group)
	}

	if made.PackCh == 0 {
		t.Error("created object has no pack letter: add_pack never filed it")
	}
}

// TestCreateObjGoldAsksHowMuch covers the GOLD arm, C's
// msg("how much?") followed by get_num(&obj->o_goldval, stdscr).
func TestCreateObjGoldAsksHowMuch(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 22, 1)
	before := packSet(g)

	setInput(t, g, Gold, '0', '2', '5', '0', '\n', ' ', Escape)
	g.createObj()

	made := onlyNewItem(t, g, before)

	if made.Kind != KindGold {
		t.Fatalf("created %v, want %v", made.Kind, KindGold)
	}

	if made.GoldValue != 250 {
		t.Errorf("gold value = %d, want the typed 250", made.GoldValue)
	}
}

// TestCreateWeaponBlessing pins the weapon arm of create_obj to C:
//
//	if (bless == '-') obj->o_flags |= ISCURSED;
//	if (obj->o_type == WEAPON) {
//	    init_weapon(obj, obj->o_which);
//	    if (bless == '-') obj->o_hplus -= rnd(3)+1;
//	    if (bless == '+') obj->o_hplus += rnd(3)+1;
//
// A curse subtracts and a blessing adds — the opposite of the armor arm
// below, and rnd(3)+1 is 1..3 either way.
//
// The curse itself does not survive on a weapon, and that is C's own
// behavior, not a port bug: weapons.c init_weapon *assigns*
// weap->o_flags = iwp->iw_flags, so it overwrites the ISCURSED bit set
// three lines earlier with the init_dam[] row's flags. A wizard-created
// "cursed" weapon therefore carries only the hit penalty and can still be
// dropped and unwielded. The mace row's flags are 0, so the whole word
// must come back 0 here whatever was answered. The armor arm has no such
// clobber, which is why TestCreateArmorBlessing does expect ISCURSED.
func TestCreateWeaponBlessing(t *testing.T) {
	t.Parallel()

	cases := []struct {
		name    string
		bless   byte
		low, hi int
	}{
		{"no blessing", 'n', 0, 0},
		{"blessed adds to the hit bonus", '+', 1, 3},
		{"cursed subtracts from it", '-', -3, -1},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			g := mkWizard(t, 23, 1)
			obj := newObject()
			obj.Kind = KindWeapon
			obj.Which = int(WeaponMace)

			setInput(t, g, tc.bless, ' ', Escape)
			g.createWeaponArmor(obj)

			if obj.Flags != 0 {
				t.Errorf("flags = %d, want the init_dam mace row's 0: "+
					"init_weapon assigns o_flags over any curse",
					obj.Flags)
			}

			if obj.HPlus < tc.low || obj.HPlus > tc.hi {
				t.Errorf("hit bonus = %d, want %d..%d",
					obj.HPlus, tc.low, tc.hi)
			}

			// init_weapon ran: the mace row of C's init_dam[].
			if got := obj.Damage.String(); got != "2x4" {
				t.Errorf("damage = %q, want the init_dam mace row 2x4", got)
			}

			if got := obj.HurlDmg.String(); got != "1x3" {
				t.Errorf("hurl damage = %q, want 1x3", got)
			}
		})
	}
}

// TestCreateArmorBlessing pins the armor arm, where C moves o_arm the
// other way because a lower armor class is better:
//
//	obj->o_arm = a_class[obj->o_which];
//	if (bless == '-') obj->o_arm += rnd(3)+1;
//	if (bless == '+') obj->o_arm -= rnd(3)+1;
//
// extern.c's a_class[] has PLATE_MAIL at 3, so the three answers land at
// 3, 0..2 and 4..6.
func TestCreateArmorBlessing(t *testing.T) {
	t.Parallel()

	cases := []struct {
		name    string
		bless   byte
		cursed  bool
		low, hi int
	}{
		{"no blessing leaves the table value", 'n', false, 3, 3},
		{"blessed lowers the armor class", '+', false, 0, 2},
		{"cursed raises it", '-', true, 4, 6},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			g := mkWizard(t, 24, 1)
			obj := newObject()
			obj.Kind = KindArmor
			obj.Which = int(ArmorPlateMail)

			setInput(t, g, tc.bless, ' ', Escape)
			g.createWeaponArmor(obj)

			if got := obj.Flags.Has(Cursed); got != tc.cursed {
				t.Errorf("cursed = %v, want %v", got, tc.cursed)
			}

			if obj.ArmorClass < tc.low || obj.ArmorClass > tc.hi {
				t.Errorf("armor class = %d, want %d..%d",
					obj.ArmorClass, tc.low, tc.hi)
			}

			// The armor arm must not fall into init_weapon.
			if obj.Kind != KindArmor || obj.Which != int(ArmorPlateMail) {
				t.Errorf("armor became %v which %d", obj.Kind, obj.Which)
			}
		})
	}
}

// TestCreateRingBonus covers the four bonus rings, C's
// obj->o_arm = (bless == '-' ? -1 : rnd(2) + 1), where rnd(2)+1 is 1..2.
// R_ADDHIT is RingDexterity and R_ADDDAM is RingIncreaseDamage; the
// RingKind iota matches C's R_ numbering index for index.
func TestCreateRingBonus(t *testing.T) {
	t.Parallel()

	rings := []RingKind{
		RingProtection, RingAddStrength, RingDexterity, RingIncreaseDamage,
	}

	blessings := []struct {
		name    string
		bless   byte
		cursed  bool
		low, hi int
	}{
		{"blessed", '+', false, 1, 2},
		{"unblessed", 'n', false, 1, 2},
		{"cursed", '-', true, -1, -1},
	}

	for _, ring := range rings {
		for _, tc := range blessings {
			t.Run(ringTestName(ring, tc.name), func(t *testing.T) {
				t.Parallel()

				g := mkWizard(t, 25, 1)
				obj := newObject()
				obj.Kind = KindRing
				obj.Which = int(ring)

				setInput(t, g, tc.bless, ' ', Escape)
				g.createRing(obj)

				if got := obj.Flags.Has(Cursed); got != tc.cursed {
					t.Errorf("cursed = %v, want %v", got, tc.cursed)
				}

				if obj.Bonus < tc.low || obj.Bonus > tc.hi {
					t.Errorf("bonus = %d, want %d..%d",
						obj.Bonus, tc.low, tc.hi)
				}

				if used := inputUsed(t, g); used != 1 {
					t.Errorf("read %d keys, want the 1 blessing answer",
						used)
				}
			})
		}
	}
}

// ringTestName labels a subtest by ring index, the R_ number from rogue.h.
func ringTestName(ring RingKind, what string) string {
	return "R_" + strconv.Itoa(int(ring)) + " " + what
}

// TestCreateRingCursedKindsSkipThePrompt covers C's second case group,
// "when R_AGGR: case R_TELEPORT: obj->o_flags |= ISCURSED": cursed with
// no blessing question and no bonus at all.
func TestCreateRingCursedKindsSkipThePrompt(t *testing.T) {
	t.Parallel()

	for _, ring := range []RingKind{RingAggravateMonsters, RingTeleportation} {
		t.Run(ringTestName(ring, "is cursed silently"), func(t *testing.T) {
			t.Parallel()

			g := mkWizard(t, 26, 1)
			obj := newObject()
			obj.Kind = KindRing
			obj.Which = int(ring)

			setInput(t, g, ' ', Escape)
			g.createRing(obj)

			if !obj.Flags.Has(Cursed) {
				t.Error("ring is not cursed")
			}

			if obj.Bonus != 0 {
				t.Errorf("bonus = %d, want 0: C sets none here", obj.Bonus)
			}

			if used := inputUsed(t, g); used != 0 {
				t.Errorf("read %d keys; C asks nothing for this kind", used)
			}
		})
	}
}

// TestCreateRingOtherKindsAreLeftAlone is the default arm: every ring
// outside C's two case groups gets no prompt, no curse and no bonus.
func TestCreateRingOtherKindsAreLeftAlone(t *testing.T) {
	t.Parallel()

	others := []RingKind{
		RingSustainStrength, RingSearching, RingSeeInvisible, RingAdornment,
		RingRegeneration, RingSlowDigestion, RingStealth, RingMaintainArmor,
	}

	for _, ring := range others {
		t.Run(ringTestName(ring, "is untouched"), func(t *testing.T) {
			t.Parallel()

			g := mkWizard(t, 27, 1)
			obj := newObject()
			obj.Kind = KindRing
			obj.Which = int(ring)

			setInput(t, g, ' ', Escape)
			g.createRing(obj)

			if obj.Flags.Has(Cursed) {
				t.Error("ring was cursed; C curses only R_AGGR and R_TELEPORT")
			}

			if obj.Bonus != 0 {
				t.Errorf("bonus = %d, want 0", obj.Bonus)
			}

			if used := inputUsed(t, g); used != 0 {
				t.Errorf("read %d keys; C asks nothing for this kind", used)
			}
		})
	}
}

// TestShowMapRendersTheWholeLevel covers wizard.c show_map against a
// generated level. C clears hw, walks y from 1 to NUMLINES-2 and x across
// every column writing chat(y,x), then show_win()s it, so the whole map
// including squares the hero has never seen has to land in the hw window.
//
// What show_map does *not* do is mark anything seen: it touches no PLACE
// at all, in C or here, so there is no F_SEEN assertion to make.
//
// The standout attribute is only asserted up to the first non-real
// square, deliberately. C's two tests are not the same test:
//
//	real = flat(y, x);
//	if (!(real & F_REAL)) wstandout(hw);
//	...
//	if (!real) wstandend(hw);        /* whole word, not the bit */
//
// new_level.c seeds every square with p_flags = F_REAL, and exactly three
// sites clear that bit. putpass sets F_PASS first, so a secret passage is
// left at 0x80. door's secret-door arm clears it on a room-wall exit whose
// flags are still exactly F_REAL, leaving p_flags == 0. And the trap loop
// ORs in rnd(NTRAPS), which is 0..7, so the T_DOOR (00) case is zero too
// until be_trapped ORs F_SEEN in. So C's wstandend does fire, at secret
// doors and unsprung trapdoors; what it gets wrong is leaking standout
// forward from a secret passage or a non-trapdoor trap until it reaches
// one of those — intermittent bands, not a permanently reversed map.
// game/wizard.go tests isReal both times and highlights the single square.
// That divergence is reported on issue #7 rather than settled here, so
// this test asserts only
// what both agree on: the characters everywhere, standout on every
// non-real square, and no standout on real squares before the first
// non-real one.
func TestShowMapRendersTheWholeLevel(t *testing.T) {
	t.Parallel()

	// Deep enough that putpass and the trap loop actually fire; both are
	// gated on the depth, so a level-1 map would have nothing secret.
	g := mkWizard(t, 31, 20)

	setInput(t, g, ' ')
	g.showMap()

	hw := g.scr.Hw
	seenSecret := false

	for y := 1; y < NumLines-1; y++ {
		for x := range NumCols {
			c := hw.at(y, x)
			if c.ch != g.Level.Char(y, x) {
				t.Fatalf("hw(%d,%d) = %q, want the map char %q",
					y, x, c.ch, g.Level.Char(y, x))
			}

			isReal := g.Level.FlagsAt(y, x).Has(FReal)
			if !isReal && !c.standout {
				t.Errorf("secret square (%d,%d) was not drawn in standout",
					y, x)
			}

			if !seenSecret && isReal && c.standout {
				t.Errorf("ordinary square (%d,%d) was drawn in standout",
					y, x)
			}

			seenSecret = seenSecret || !isReal
		}
	}

	if !seenSecret {
		t.Fatal("generated level has no non-F_REAL squares: the standout " +
			"half of show_map went untested, pick a deeper level or seed")
	}
}

// TestShowMapLoopBoundsMatchC pins the loop bounds. C starts at y = 1
// and stops before NUMLINES-1, so the top line stays free for show_win's
// prompt and the status line is never overwritten.
func TestShowMapLoopBoundsMatchC(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 32, 10)

	// Rows 0 and NUMLINES-1 are blank on a generated level, so a bound
	// that ran off either end would copy blanks onto blanks and look
	// identical. Planting a marker in places[] there is what makes the
	// bound observable at all.
	const marker = 'Z'

	for x := range NumCols {
		g.Level.SetChar(0, x, marker)
		g.Level.SetChar(NumLines-1, x, marker)
	}

	setInput(t, g, ' ')
	g.showMap()

	hw := g.scr.Hw

	for x := range NumCols {
		if got := hw.at(NumLines-1, x).ch; got == marker {
			t.Fatalf("hw(%d,%d) = %q: the loop ran onto the status line",
				NumLines-1, x, got)
		}
	}

	const want = "---More (level map)---"

	// show_win's prompt covers the start of row 0; past it the row must
	// still be untouched by the map loop.
	for x := len(want); x < NumCols; x++ {
		if got := hw.at(0, x).ch; got == marker {
			t.Fatalf("hw(0,%d) = %q: the loop ran onto the message line",
				x, got)
		}
	}

	top := make([]byte, 0, len(want))

	for x := range len(want) {
		top = append(top, hw.at(0, x).ch)
	}

	if string(top) != want {
		t.Errorf("top line = %q, want show_win's %q", string(top), want)
	}
}

// TestWhatisMarksTheRightTable covers wizard.c whatis's switch: scrolls,
// potions, sticks and rings each go through set_know on their own
// per-game table, and the function ends with msg(inv_name(obj, FALSE)),
// so the reported name is the newly identified one.
func TestWhatisMarksTheRightTable(t *testing.T) {
	t.Parallel()

	cases := []struct {
		name  string
		kind  ObjectKind
		which int
		table func(g *RogueGame) []ObjInfo
	}{
		{"scroll", KindScroll, int(ScrollEnchantArmor),
			func(g *RogueGame) []ObjInfo { return g.Items.Scrolls[:] }},
		{"potion", KindPotion, int(PotionHealing),
			func(g *RogueGame) []ObjInfo { return g.Items.Potions[:] }},
		{"wand", KindWand, int(WandLight),
			func(g *RogueGame) []ObjInfo { return g.Items.Sticks[:] }},
		{"ring", KindRing, int(RingSearching),
			func(g *RogueGame) []ObjInfo { return g.Items.Rings[:] }},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			g := mkWizard(t, 33, 1)
			obj := newObject()
			obj.Kind = tc.kind
			obj.Which = tc.which
			ch := give(g, obj)

			tbl := tc.table(g)
			tbl[tc.which].Guess = "a wild guess"
			before := g.inventoryName(obj, false)

			setInput(t, g, ch, ' ', Escape)
			g.whatis(false, KindNone)

			if !tbl[tc.which].Know {
				t.Error("set_know did not mark the table entry known")
			}

			if tbl[tc.which].Guess != "" {
				t.Errorf("guess = %q, want it freed", tbl[tc.which].Guess)
			}

			if !obj.Flags.Has(Known) {
				t.Error("the object did not get ISKNOW")
			}

			after := g.inventoryName(obj, false)
			if after == before {
				t.Errorf("name is still %q; identifying changed nothing",
					after)
			}

			if g.Msgs.Huh != after {
				t.Errorf("reported %q, want inv_name's %q", g.Msgs.Huh, after)
			}
		})
	}
}

// TestWhatisIdentifiesOnlyTheChosenEntry is the other half of set_know's
// contract: one table entry, not a whole table and not its neighbours.
func TestWhatisIdentifiesOnlyTheChosenEntry(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 34, 1)
	obj := newObject()
	obj.Kind = KindScroll
	obj.Which = int(ScrollEnchantArmor)
	ch := give(g, obj)

	setInput(t, g, ch, ' ', Escape)
	g.whatis(false, KindNone)

	for i := range g.Items.Scrolls {
		if i == obj.Which {
			continue
		}

		if g.Items.Scrolls[i].Know {
			t.Errorf("scroll %d was marked known too", i)
		}
	}

	if g.Items.Potions[obj.Which].Know {
		t.Error("identifying a scroll marked the potion at the same index")
	}
}

// TestWhatisWeaponAndArmorOnlySetTheFlag pins C's WEAPON/ARMOR arm, which
// is "obj->o_flags |= ISKNOW" and no set_know call: knowing this sword is
// a sword says nothing about the kind, so the per-kind table entry must
// stay untouched.
func TestWhatisWeaponAndArmorOnlySetTheFlag(t *testing.T) {
	t.Parallel()

	cases := []struct {
		name  string
		kind  ObjectKind
		which int
		table func(g *RogueGame) []ObjInfo
	}{
		{"a mace", KindWeapon, int(WeaponMace),
			func(g *RogueGame) []ObjInfo { return g.Items.Weapons[:] }},
		{"plate mail", KindArmor, int(ArmorPlateMail),
			func(g *RogueGame) []ObjInfo { return g.Items.Armors[:] }},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			g := mkWizard(t, 35, 1)
			obj := newObject()
			obj.Kind = tc.kind
			obj.Which = tc.which
			ch := give(g, obj)

			setInput(t, g, ch, ' ', Escape)
			g.whatis(false, KindNone)

			if !obj.Flags.Has(Known) {
				t.Error("the object did not get ISKNOW")
			}

			if tc.table(g)[tc.which].Know {
				t.Error("the kind table was marked known; C calls no " +
					"set_know for weapons or armor")
			}
		})
	}
}

// TestWhatisEmptyPackSaysSo covers the early return C takes when
// pack == NULL, before any prompt happens.
func TestWhatisEmptyPackSaysSo(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 36, 1)
	g.Player.Pack = nil

	g.whatis(false, KindNone)

	const want = "you don't have anything in your pack to identify"

	if g.Msgs.Huh != want {
		t.Errorf("message = %q, want %q", g.Msgs.Huh, want)
	}

	if used := inputUsed(t, g); used != 0 {
		t.Errorf("read %d keys; C returns before get_item", used)
	}
}

// TestWhatisInsistRepromptsUntilAMatch drives both re-prompting arms of
// C's insist loop in one pass: a wrong-kind pick ("you must identify a
// %s") and then a bare escape with n_objs non-zero ("you must identify
// something"), before the scroll finally satisfies it. The spaces in the
// script are the --More-- acknowledgements those two messages force, and
// without insist neither arm exists — the loop would have returned the
// potion on the first answer.
func TestWhatisInsistRepromptsUntilAMatch(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 37, 1)

	pot := newObject()
	pot.Kind = KindPotion
	pot.Which = int(PotionHealing)
	potCh := give(g, pot)

	scr := newObject()
	scr.Kind = KindScroll
	scr.Which = int(ScrollEnchantArmor)
	scrCh := give(g, scr)

	setInput(t, g, potCh, ' ', Escape, ' ', scrCh, ' ', Escape)
	g.whatis(true, KindScroll)

	if !g.Items.Scrolls[scr.Which].Know {
		t.Error("the scroll was never identified: the loop gave up early")
	}

	if g.Items.Potions[pot.Which].Know {
		t.Error("the wrong-kind potion was identified anyway")
	}

	if used := inputUsed(t, g); used < 5 {
		t.Errorf("consumed %d keys, want at least the 5 the two "+
			"re-prompts need", used)
	}
}

// TestWhatisInsistGivesUpWhenNothingMatches covers "if (n_objs == 0)
// return": asking for the list with nothing appropriate in the pack sets
// n_objs to 0, and that is the one way out of the insist loop short of
// picking something. Getting it wrong is not a wrong answer but a hang.
func TestWhatisInsistGivesUpWhenNothingMatches(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 38, 1)
	pot := newObject()
	pot.Kind = KindPotion
	pot.Which = int(PotionHealing)
	give(g, pot)

	setInput(t, g, '*', ' ', Escape)
	g.whatis(true, KindScroll)

	if g.NObjs != 0 {
		t.Fatalf("n_objs = %d; this test needs the empty-list path", g.NObjs)
	}

	if g.Items.Potions[pot.Which].Know {
		t.Error("giving up identified something anyway")
	}
}

// TestSetKnowDoesNotLeakAcrossGames is the reason set_know is not just a
// debug helper: the tables it writes are the per-game discovered lists
// that drive item naming in ordinary play. They live on RogueGame, and a
// second game must start ignorant.
func TestSetKnowDoesNotLeakAcrossGames(t *testing.T) {
	t.Parallel()

	g1 := mkWizard(t, 39, 1)
	g2 := mkWizard(t, 40, 1)

	ring := newObject()
	ring.Kind = KindRing
	ring.Which = int(RingSearching)
	g1.Items.Rings[ring.Which].Guess = "a hunch"

	setKnow(ring, g1.Items.Rings[:])

	if !g1.Items.Rings[ring.Which].Know {
		t.Error("the entry was not marked known")
	}

	if g1.Items.Rings[ring.Which].Guess != "" {
		t.Error("the old guess was not freed")
	}

	if !ring.Flags.Has(Known) {
		t.Error("the object did not get ISKNOW")
	}

	if g2.Items.Rings[ring.Which].Know {
		t.Error("the second game already knows the ring: the discovered " +
			"tables are shared between games")
	}

	if g2.Items.Rings[ring.Which].Guess != "" {
		t.Error("the second game inherited the first game's guess")
	}
}

// TestTeleportLandsTheHeroSomewhereLegal covers wizard.c teleport. C
// picks the spot with find_floor(NULL, &c, FALSE, TRUE) — any room, and
// monst TRUE, so the square must be steppable and unoccupied — then keeps
// the room bookkeeping straight (leave_room/enter_room when the room
// changed, look(TRUE) when it did not) and clears the run state.
func TestTeleportLandsTheHeroSomewhereLegal(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 41, 3)
	p := &g.Player
	from := p.Pos
	vacated := g.floorAt()

	g.NoMove = 3
	g.Count = 5
	g.Running = true

	g.teleport()

	if p.Pos == from {
		t.Fatal("hero did not move; this seed teleported him onto himself")
	}

	pp := g.Level.At(p.Pos.Y, p.Pos.X)
	if !stepOk(pp.Ch) || pp.Monst != nil {
		t.Errorf("landed on %q with monster %v: find_floor's contract is "+
			"a steppable, unoccupied square", pp.Ch, pp.Monst != nil)
	}

	if p.Room != g.roomIn(p.Pos) {
		t.Error("player room does not match the square he is standing on")
	}

	if got := g.mvinch(p.Pos.Y, p.Pos.X); got != PlayerCh {
		t.Errorf("new square shows %q, want the hero %q", got, PlayerCh)
	}

	if got := g.mvinch(from.Y, from.X); got != vacated {
		t.Errorf("vacated square shows %q, want floor_at()'s %q",
			got, vacated)
	}

	if g.NoMove != 0 || g.Count != 0 || g.Running {
		t.Errorf("run state left at no_move=%d count=%d running=%v",
			g.NoMove, g.Count, g.Running)
	}
}

// TestTeleportReleasesTheFlytrap covers the tail C spells out: bamfing
// away while a Flytrap has hold of you clears ISHELD, resets vf_hit and
// puts the 'F' bestiary entry's damage back to "000x0" — the Flytrap
// grows its own damage string as it holds on, so leaving it grown would
// make the next Flytrap of the game start off mid-fight.
func TestTeleportReleasesTheFlytrap(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 42, 3)
	p := &g.Player
	p.Flags.Set(Held)
	p.VfHit = 4
	g.Monsters['F'-'A'].Stats.Dmg = dice("3x4")

	g.teleport()

	if p.On(Held) {
		t.Error("hero is still held after teleporting away")
	}

	if p.VfHit != 0 {
		t.Errorf("vf_hit = %d, want 0", p.VfHit)
	}

	// C strcpy's the literal "000x0"; the port keeps damage parsed, so
	// the same thing reads back as the single 0x0 attack that string
	// means rather than as those five characters.
	dmg := g.Monsters['F'-'A'].Stats.Dmg
	if len(dmg) != 1 || dmg[0].Count != 0 || dmg[0].Sides != 0 {
		t.Errorf("flytrap damage = %q, want C's 000x0, one 0x0 attack", dmg)
	}
}

// TestTeleportLeavesTheFlytrapAloneWhenFree pins the other side of C's
// "if (on(player, ISHELD))" guard: an ordinary wizard teleport must not
// reach into the bestiary and reset a Flytrap that is busy elsewhere.
func TestTeleportLeavesTheFlytrapAloneWhenFree(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 43, 3)
	g.Player.VfHit = 2
	g.Monsters['F'-'A'].Stats.Dmg = dice("3x4")

	g.teleport()

	if g.Player.VfHit != 2 {
		t.Errorf("vf_hit = %d, want the untouched 2", g.Player.VfHit)
	}

	if got := g.Monsters['F'-'A'].Stats.Dmg.String(); got != "3x4" {
		t.Errorf("flytrap damage = %q, want the untouched %q", got, "3x4")
	}
}

// TestWizardKitEquipsTheHero covers the CTRL('I') arm of command.c's
// wizard switch: nine raise_level() calls, a (+1,+1) two-handed sword
// wielded, and plate mail at o_arm -5 already known and worn.
func TestWizardKitEquipsTheHero(t *testing.T) {
	t.Parallel()

	g := mkWizard(t, 44, 1)
	p := &g.Player

	if p.Stats.Lvl != 1 {
		t.Fatalf("hero starts at level %d, not 1", p.Stats.Lvl)
	}

	// raise_level messages queue up --More-- prompts; spaces clear them.
	setInput(t, g, ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ')
	g.wizardKit()

	if p.Stats.Lvl != 10 {
		t.Errorf("level = %d, want 10 after nine raise_level calls",
			p.Stats.Lvl)
	}

	checkKitWeapon(t, g)
	checkKitArmor(t, g)
}

// checkKitWeapon asserts the sword half of the wizard kit.
func checkKitWeapon(t *testing.T, g *RogueGame) {
	t.Helper()

	weap := g.Player.CurWeapon
	if weap == nil {
		t.Fatal("no weapon wielded")
	}

	if weap.Kind != KindWeapon || weap.Which != int(WeaponTwoHandedSword) {
		t.Errorf("wielding %v which %d, want the two-handed sword",
			weap.Kind, weap.Which)
	}

	if weap.HPlus != 1 || weap.DPlus != 1 {
		t.Errorf("sword is (%+d,%+d), want (+1,+1)", weap.HPlus, weap.DPlus)
	}

	// init_dam[]'s 2h sword row.
	if got := weap.Damage.String(); got != "4x4" {
		t.Errorf("damage = %q, want 4x4", got)
	}

	if !inPack(g, weap) {
		t.Error("the sword was never added to the pack")
	}
}

// checkKitArmor asserts the plate mail half of the wizard kit.
func checkKitArmor(t *testing.T, g *RogueGame) {
	t.Helper()

	armor := g.Player.CurArmor
	if armor == nil {
		t.Fatal("no armor worn")
	}

	if armor.Kind != KindArmor || armor.Which != int(ArmorPlateMail) {
		t.Errorf("wearing %v which %d, want plate mail",
			armor.Kind, armor.Which)
	}

	if armor.ArmorClass != -5 {
		t.Errorf("armor class = %d, want -5", armor.ArmorClass)
	}

	if !armor.Flags.Has(Known) {
		t.Error("the armor is not known")
	}

	if armor.Count != 1 {
		t.Errorf("count = %d, want 1", armor.Count)
	}

	if !inPack(g, armor) {
		t.Error("the armor was never added to the pack")
	}
}

// inPack reports whether obj is filed in the hero's pack.
func inPack(g *RogueGame, obj *Object) bool {
	return slices.Contains(g.Player.Pack, obj)
}