feat(gen2): share battle UI visibility hooks

docs/mod-api-gen2-compat.md

@@ -533,8 +533,9 @@ gains a field instead of the name gaining a prefix.
   `pokemon.level_up`, `pokemon.move_learned`; hooks `battle.damage`,
   `battle.crit`, `battle.accuracy`, `battle.turn_order`,
   `battle.enemy_action`, `battle.run`, `battle.exp_award`, `exp.gain`,
-  `catch.rate`, `trainer.party`, `battle.overlay`, `battle.low_health_alarm`
-  and `battle.catch_exp`. One payload difference: Gen 1's vanilla
+  `catch.rate`, `trainer.party`, `battle.overlay`, `battle.low_health_alarm`,
+  `battle.catch_exp`, `battle.bottom_ui_visible` and
+  `battle.status_hud_visible`. One payload difference: Gen 1's vanilla
   `battle.low_health_alarm` link reads `ctx.battle.data`, and Gold's battle
   screen has no `.data` field, so the Gen 2 site **adds** `ctx.data` beside the
   Gen 1 keys. A mod that calls `nextFn` is unaffected; one that reaches through

docs/modding.md

@@ -455,6 +455,7 @@ identifiers: `pc_box_withdraw`, `pc_box_deposit`, `pc_box_release`,
 `battle.bottom_ui_visible` and `battle.status_hud_visible` independently
 control the battle text/menu layer and the HP/status panels. Both receive
 `(next, state)` and default to `true`, so vanilla rendering is unchanged.
+Both hooks apply to Gen 1 and Gen 2 battles.
 Text boxes and YES/NO prompts pushed above a battle inherit a `false` result
 for that battle, so hiding the bottom layer cannot leave their white backing
 behind under another overlay. Text boxes also pass through the hook as their

src/ui/gen2/BattleState.lua

@@ -173,6 +173,18 @@ end
 function BattleState:wantsFillScale() return true end
 function BattleState:drawsWidescreen() return true end
 
+function BattleState:bottomUIVisible()
+  if not Runtime.wantsHook("battle.bottom_ui_visible") then return true end
+  return Runtime.call("battle.bottom_ui_visible", function() return true end,
+                      self) ~= false
+end
+
+function BattleState:statusHUDVisible()
+  if not Runtime.wantsHook("battle.status_hud_visible") then return true end
+  return Runtime.call("battle.status_hud_visible", function() return true end,
+                      self) ~= false
+end
+
 -- opts: battle (a Battle), onDone(outcome), save
 function BattleState.new(game, opts)
   opts = opts or {}
@@ -3079,6 +3091,7 @@ end
 function BattleState:drawHud()
   local wasBattle = Font.useBattleExtra(true)
   local enemy, player = self:activeMon("enemy"), self:activeMon("player")
+  local showStatus = self:statusHUDVisible()
 
   -- Enemy HUD (DrawEnemyHUD clears (1,0) 4 rows x 11 cols):
   --   name at (1,0); PrintLevel at (6,1) with the gender symbol at (9,1);
@@ -3087,7 +3100,7 @@ function BattleState:drawHud()
   -- runs, so a shake or a slide does not drag the HP bar with it.
   -- And nothing at all before UpdateEnemyHUD has ever run: the intro bands
   -- slide in over a blanked tilemap (core.asm:8554/8564).
-  if self.showEnemyHud and not self:hudCleared("enemy") then
+  if showStatus and self.showEnemyHud and not self:hudCleared("enemy") then
   Chrome.print(self:name(enemy), 1, 0)
   -- PrintLevel writes <LV> at the coordinate it is given and then LEFT-aligns
   -- the digits after it, so the glyph is pinned to column 6 whether the level
@@ -3127,7 +3140,8 @@ function BattleState:drawHud()
   -- BattleMenu's own tutorial arm skips UpdateBattleHuds as well.  The DUDE's
   -- half of the screen is his back-pic and nothing more.
   -- Nor before SendOutPlayerMon's own UpdatePlayerHUD (core.asm:3838).
-  if not player or not self.showPlayerHud or self:hudCleared("player") then
+  if not showStatus or not player or not self.showPlayerHud
+      or self:hudCleared("player") then
     Font.useBattleExtra(wasBattle)
     return
   end
@@ -3226,6 +3240,11 @@ function BattleState:drawPanel()
   end
   self:drawHud()
 
+  if not self:bottomUIVisible() then
+    love.graphics.setColor(1, 1, 1, 1)
+    return
+  end
+
   -- Message box across the bottom, with the menu window over its right half --
   -- the cart draws the prompt into the full-width box and then opens the menu
   -- on top, so the tail of a long name is simply covered.

tests/engine/gate_gen2_mod_api.lua

@@ -420,6 +420,7 @@ local GEN2_HOOKS = {
   -- that a Gen 1 mod reaching through ctx.battle.data instead of calling
   -- nextFn gets nil there).
   "battle.catch_exp", "battle.low_health_alarm", "battle.overlay",
+  "battle.bottom_ui_visible", "battle.status_hud_visible",
   -- One pic path resolver for both games: the Gen 1 site is the SHARED
   -- src/pokemon/Sprites.lua and Gold's own battle screen calls the same hook
   -- with the Gen 1 ctx keys plus `letter` and `shiny`, which Red has no

tests/mod_qol_hooks_tests.lua

@@ -168,8 +168,11 @@ end
 
 do
   local BattleState = require("src.battle.BattleState")
+  local Gen2BattleState = require("src.ui.gen2.BattleState")
   check(BattleState.bottomUIVisible({ phase = "menu" }),
     "battle bottom UI is visible without a mod")
+  check(Gen2BattleState.bottomUIVisible({ phase = "menu" }),
+    "Gold battle bottom UI is visible without a mod")
   local seen
   local unsub = wrap("battle.bottom_ui_visible", function(_, state)
     seen = state
@@ -177,6 +180,8 @@ do
   end)
   check(not BattleState.bottomUIVisible({ phase = "messages" }),
     "a mod can hide the battle text and menu layer")
+  check(not Gen2BattleState.bottomUIVisible({ phase = "menu" }),
+    "the same hook hides Gold's battle text and menu layer")
   local text = setmetatable({}, TextBox)
   text:draw()
   check(seen == text, "pushed text boxes use the same visibility hook")
@@ -200,15 +205,41 @@ do
 
   check(BattleState.bottomUIVisible({ phase = "moveSelect" }),
     "battle bottom UI returns when the hook is removed")
+  check(Gen2BattleState.bottomUIVisible({ phase = "moves" }),
+    "Gold battle bottom UI returns when the hook is removed")
+
+  local Chrome = require("src.ui.gen2.Chrome")
+  local clear, box, print = Chrome.clear, Chrome.box, Chrome.print
+  local boxes = 0
+  Chrome.clear = function() end
+  Chrome.box = function() boxes = boxes + 1 end
+  Chrome.print = function() end
+  local panel = setmetatable({
+    battle = { player = {}, enemy = {} }, phase = "resolving",
+    drawHud = function() end,
+  }, { __index = Gen2BattleState })
+  unsub = wrap("battle.bottom_ui_visible", function() return false end)
+  panel:drawPanel()
+  check(boxes == 0, "Gold skips its in-state battle box when a mod owns it")
+  unsub()
+  panel:drawPanel()
+  check(boxes == 1, "Gold draws its battle box again without the hook")
+  Chrome.clear, Chrome.box, Chrome.print = clear, box, print
 
   check(BattleState.statusHUDVisible({}),
     "battle status HUD is visible without a mod")
+  check(Gen2BattleState.statusHUDVisible({}),
+    "Gold battle status HUD is visible without a mod")
   unsub = wrap("battle.status_hud_visible", function() return false end)
   check(not BattleState.statusHUDVisible({}),
     "a mod can hide the battle status HUD")
+  check(not Gen2BattleState.statusHUDVisible({}),
+    "the same hook hides Gold's battle status HUD")
   unsub()
   check(BattleState.statusHUDVisible({}),
     "battle status HUD returns when the hook is removed")
+  check(Gen2BattleState.statusHUDVisible({}),
+    "Gold battle status HUD returns when the hook is removed")
 end
 
 -- ------- battle.caught_marker_visible (caught wild marker)