' 21 点（BLACKJACK）—— 用 **BASIC** 写的手机游戏
' Blackjack -- a mobile game written in **BASIC**
'
' 出处与版权：原型是 1970 年代流传最广的那份 21 点 BASIC 程序（收进 David Ahl 的
' Origin and copyright: the prototype is the most widely circulated blackjack BASIC
' 《BASIC Computer Games》，原版叫 BLACKJACK 或 21）。**这份是照玩法规则重写的**：
' program of the 1970s (collected in David Ahl's "BASIC Computer Games"; the original was called BLACKJACK or 21).
' 结构、变量名、注释、绘制方式都是自己的，没有抄原件的一行代码 ——
' **This one is rewritten from the rules of play**: the structure, variable names, comments and drawing
' 与 `gorilla.bas` 同一条规矩（`Examples/` 会随 APK 分发）。
' are all our own -- not one line copied from the original, the same rule as `gorilla.bas` (`Examples/` ships with the APK).
'
' 玩法：标准赌场规则简化版 —— 庄家 17 点停（软 17 也停）、A 可当 1 或 11、
' Play: a simplified version of standard casino rules -- the dealer stands on 17 (soft 17 too), an ace counts 1 or 11,
' 天生 21 点（两张就 21）赔 3:2、其余赢赔 1:1、和局退还赌注。筹码有限，输光就结束。
' a natural 21 (two cards) pays 3:2, other wins pay 1:1 and a push returns the bet. Chips are finite; losing them all ends the game.
'
' ◆ 手机上怎么玩
' ◆ How to play it on a phone
'
' 原版是打字问「要不要牌（H/S）」，这里改成**三个大按钮**：要牌 / 停牌 / 加倍。
' The original asked you to type whether to take a card (H/S); here it is **three big buttons**: Hit / Stand / Double.
' 赌注用 −/+ 调（下注阶段），发牌后按钮换成要牌/停牌/加倍。
' The bet is adjusted with -/+ during the betting phase, and after the deal the buttons become Hit/Stand/Double.
' —— 回合制游戏在手机上就该这么处理：**别让玩家调键盘**。
' -- that is how a turn-based game should be handled on a phone: **never make the player work a keyboard**.
'
' ◆ 写法提醒（这几条是本前端**当前**的硬约束，都不是"建议"）
' ◆ Writing notes (these are **current** hard constraints of this frontend, not "suggestions")
'
'   · **数组维度必须写字面量**：`DIM a(N) AS INTEGER`（N 是 CONST）**不生效** ——
'   · **Array dimensions must be written as literals**: `DIM a(N) AS INTEGER` (N being a CONST) **does not take effect** --
'     实测 `a(4)` 恒为 0，而 `DIM a(5)` 正常（见 FRONTEND_DEFECTS.md 的 BASIC 一节）。
'     measured: `a(4)` is always 0, while `DIM a(5)` works (see the BASIC section of FRONTEND_DEFECTS.md).
'   · **有返回值的必须写 `FUNCTION`**（`SUB … AS INTEGER` 会去链一个 `func_integer`），
'   · **Anything with a return value must be written as `FUNCTION`** (`SUB ... AS INTEGER` goes off and links a `func_integer`),
'     且收尾必须是 `END FUNCTION`（写成 `END SUB` 会让整个解析错位）。
'     and it must end with `END FUNCTION` (writing `END SUB` derails the whole parse).
'   · ~~**不要写无参 `FUNCTION`**（它恒返回 0）~~ —— ✅ **2026-10-04 复验已修好**：
'   · ~~**Do not write a parameterless `FUNCTION`** (it always returned 0)~~ — ✅ **re-checked fixed on 2026-10-04**:
'     实测 `FUNCTION roll() / roll = 7 / END FUNCTION` 打出 `7`。
'     measured: `FUNCTION roll() / roll = 7 / END FUNCTION` prints `7`.
'   · 外部过程写 `NATIVE SUB` / `NATIVE FUNCTION` + 空体（这份照旧这么写）。⚠ 当年是**必须**的、
'   · External procedures are written `NATIVE SUB` / `NATIVE FUNCTION` plus an empty body (this file still writes it that way). ⚠ Back then it was **required**
'     **2026-10-04 复验已不必**（链接期会认领库侧符号，实测不写 `NATIVE` 照样拿到真值 480）。
'     and **re-checked 2026-10-04: no longer needed** (the linker claims the library-side symbol; measured: without `NATIVE` it still returns the real value 480).
'   · 颜色写 `&HFFrrggbb`。
'   · Colors are written as `&HFFrrggbb`.

' ── UI 接口：引用**库侧**的声明文件（原先这里是一屏 NATIVE 声明）────────────────
' ── UI interface: include the **library-side** declaration file (this used to be a screenful of NATIVE declarations)
'$INCLUDE: 'vml_ui.bas'
' 音效：**用 `ui_audio_beep` 单音**（v0.96.509 统一换回来）。
' Sound: **use the single-tone `ui_audio_beep`** (switched back uniformly in v0.96.509).
' ⚠⚠ 一度走共享库的音序器（`ui_sfx_add`），**真机上破音**（多个音叠着响 + 长音拖尾）
' ⚠⚠ It once went through the shared library's sequencer (`ui_sfx_add`), which **clips on real devices**
'   ⇒ 全换回单音的 beep：它是**单通道**的（后一个音掐掉前一个），结构上不可能削波。
'   (several tones ringing on top of each other plus a long tail) => everything switched back to single-tone beeps:
' ⚠ 频率取原音型的**首音**；**胜负取两端的极值**（赢取最高音、输取最低音 ——
'   a beep is **single-channel** (the next tone cuts off the previous one), so clipping is structurally impossible.
'   「不看屏幕也分得出」就靠这个，五子棋/象棋两版也是这么配的：赢 1320 / 输 240）。
' ⚠ The frequency is the **first note** of the original pattern; **win/lose takes the extremes of both ends** (highest tone for a win,
'   低音不低于 C3(131Hz)（手机外放 200Hz 以下衰减很快，听着像没响）。
'   lowest for a loss -- "you can tell without looking at the screen" rests on exactly this; gomoku and chess are scored the same way: win 1320 / lose 240). Keep the low tone at or above C3 (131Hz), since a phone speaker rolls off fast below 200Hz and it sounds like nothing was played.
' ⚠ `ui_sfx_panic` 留着 —— 它是"全停"，退出前调一次把所有正在响的声音一起掐掉。
' ⚠ `ui_sfx_panic` is kept -- it is the "stop everything" call; run it once before exiting to cut off every ringing sound at the same time.
' ⚠ 形参名不能叫 on —— BASIC 关键字，会把 NATIVE 声明弄坏（当年实测；**2026-10-04 复验已修好**：
' ⚠ A parameter must not be named on -- it is a BASIC keyword and will break the NATIVE declaration (measured back then; **re-checked fixed on 2026-10-04**:
'   实测 `NATIVE SUB ui_grid_set(i AS INTEGER, on AS INTEGER)` 声明与调用都对）。这份**照旧**避开它。
'   measured: `NATIVE SUB ui_grid_set(i AS INTEGER, on AS INTEGER)` declares and calls correctly). This file **still** avoids it.

' ══════════════════════════════════════════════════════════════════════════
'  规则常量
'  Rule constants
' ══════════════════════════════════════════════════════════════════════════
CONST DECKN = 52             ' 一副牌
' One deck of cards
CONST MAXCARD = 12           ' 一手最多记这么多张（再多早就爆了）
' Record at most this many cards in one hand (any more and it has long since busted)
CONST DEALER_STOP = 17       ' 庄家 17 点停（软 17 也停，简化）
' The dealer stands on 17 (soft 17 too, simplified)
CONST WIN = 1
CONST LOSE = 2
CONST PUSH = 3
CONST BJPAY_N = 3            ' 天生 21 点赔 3:2
' A natural 21 pays 3:2
CONST BJPAY_D = 2
CONST HUDH = 64
CONST CARDW = 54
CONST CARDH = 76

CONST C_FELT = &HFF0E3A22
CONST C_FELT_D = &HFF0A2A1A
CONST C_HUD = &HFF14140E
CONST C_TEXT = &HFFEDEDF2
CONST C_DIM = &HFF9AA0B0
CONST C_GOLD = &HFFE8C468
CONST C_RED = &HFFE05252
CONST C_DARK = &HFF1A1A22
CONST C_CARD = &HFFF6F4EE
CONST C_CARDBK = &HFF2A3A2A
CONST C_BTN = &HFF2E4A38
CONST C_BTN_HOT = &HFF4A7A5A
CONST C_FLAT = &HFF555A66

' 阶段
' Phases
CONST PH_BET = 0
CONST PH_PLAY = 1
CONST PH_DEALER = 2
CONST PH_OVER = 3

' ══════════════════════════════════════════════════════════════════════════
'  状态（数组维度一律字面量，见文件头）
'  State (array dimensions are always literals, see the file header)
' ══════════════════════════════════════════════════════════════════════════
DIM deck(52) AS INTEGER
' ⚠ 两手牌**合成一个数组**用偏移区分（玩家 0..11 / 庄家 12..23）——
' ⚠ The two hands are **merged into one array** and told apart by an offset (player 0..11 / dealer 12..23) --
'   当年本前端**不支持数组形参**（`FUNCTION f(a(12) AS INTEGER)` 会把 `a` 当成函数调用去链接、
'   back then this frontend **did not support array parameters** (`FUNCTION f(a(12) AS INTEGER)` treated `a` as a function call
'   报 `未定义的函数 'func_a'`）；✅ **2026-10-04 复验已可用**：形参写 `a(12) AS INTEGER`（或 `BYREF b() AS ANY`）、
'   and went off to link it, reporting undefined function func_a); ✅ **re-checked 2026-10-04: they work now**: declare the parameter as `a(12) AS INTEGER` (or `BYREF b() AS ANY`)
'   **实参必须带括号写 `arr()`** —— 实测 `f(t())` 读回 9，而写成 `f(t)` 会**静默**传进一个标量、读回 0。
'   and **pass the argument as `arr()`** — measured: `f(t())` reads back 9, while `f(t)` **silently** passes a scalar and reads back 0.
'   这里**照旧**用偏移区分（能跑就别动），它同时也避开了"把算点数这条规则写两份"。
'   This file **still** tells them apart by offset (if it runs, leave it alone); that also avoids writing the card-counting rule twice.
DIM hand(24) AS INTEGER      ' 编码：点数*4 + 花色（点数 1..13）
' Encoding: rank * 4 + suit (rank 1..13)
DIM pn AS INTEGER            ' 玩家手牌数
' Number of cards in the player's hand
DIM dn AS INTEGER            ' 庄家手牌数
' Number of cards in the dealer's hand
DIM di AS INTEGER            ' 下一张牌在牌堆里的下标
' Index of the next card in the deck
DIM chips AS INTEGER
DIM bet AS INTEGER
DIM phase AS INTEGER
DIM dealerHidden AS INTEGER
DIM result AS INTEGER
DIM msg AS STRING
DIM quit AS INTEGER
DIM LANG AS INTEGER          ' 界面语言：0 中文 / 1 英文（开局查一次）
' UI language: 0 Chinese / 1 English (queried once at startup)
DIM doubled AS INTEGER

DIM sw AS INTEGER
DIM sh AS INTEGER
DIM ctlY AS INTEGER
DIM b1x AS INTEGER
DIM b1y AS INTEGER
DIM b2x AS INTEGER
DIM b2y AS INTEGER
DIM b3x AS INTEGER
DIM b3y AS INTEGER
DIM bwy AS INTEGER
DIM bwh AS INTEGER
DIM bw AS INTEGER

DIM i AS INTEGER
DIM j AS INTEGER
DIM t AS INTEGER
DIM mt AS INTEGER
DIM rx AS INTEGER
DIM ry AS INTEGER
DIM tmp AS INTEGER
DIM txt AS STRING
DIM lb AS STRING             ' 按语言取值的临时串（画文字用；别在调用的实参里写 IF）
' Temporary string chosen by language (for drawing text; do not put an IF inside a call's argument list)

' ══════════════════════════════════════════════════════════════════════════
'  规则（纯函数，自检直接打它们的返回值）
'  Rules (pure functions; the self-check prints their return values directly)
' ══════════════════════════════════════════════════════════════════════════

' 牌编码 → 点数（1..13）
' Card encoding -> rank (1..13)
FUNCTION rankOf(c AS INTEGER) AS INTEGER
    rankOf = c / 4
END FUNCTION

' 牌编码 → 花色（0..3）
' Card encoding -> suit (0..3)
FUNCTION suitOf(c AS INTEGER) AS INTEGER
    DIM r AS INTEGER
    r = c / 4
    suitOf = c - r * 4
END FUNCTION

' 一手牌的**点数**（A 先按 11 算，爆了再逐张降成 1）—— 这是全部玩法的核心
' The **value** of a hand (an ace counts 11 first and is dropped to 1 card by card once busted) -- this is the heart of the whole game
FUNCTION handValue(off AS INTEGER, n AS INTEGER) AS INTEGER
    DIM k AS INTEGER
    DIM r AS INTEGER
    DIM sum AS INTEGER
    DIM aces AS INTEGER
    k = 0
    sum = 0
    aces = 0
    WHILE k < n
        r = hand(off + k) / 4
        IF r = 1 THEN
            aces = aces + 1
            sum = sum + 11
        ELSE
            IF r > 10 THEN
                sum = sum + 10
            ELSE
                sum = sum + r
            END IF
        END IF
        k = k + 1
    WEND
    ' A 从 11 降成 1：每降一张少 10 点，降够就停
'    Drop an ace from 11 to 1: each drop loses 10 points, and it stops once enough have been dropped
    ' ⚠ 用**标志位**收尾而不是 `EXIT WHILE` —— 后者在这个前端上实测**退不出来**
' ⚠ The loop is closed by a **flag** instead of `EXIT WHILE` -- the latter **never exits** on this frontend when measured
    '   （自检卡死在第一个 `handValue` 调用上，整轮超时）。
'   (the self-check hung on the first `handValue` call and the whole run timed out).
    WHILE sum > 21
        IF aces > 0 THEN
            aces = aces - 1
            sum = sum - 10
        ELSE
            EXIT WHILE
        END IF
    WEND
    handValue = sum
END FUNCTION

' 天生 21 点（只有两张）
' A natural 21 (two cards only)
FUNCTION isBlackjack(off AS INTEGER, n AS INTEGER) AS INTEGER
    IF n = 2 THEN
        IF handValue(off, n) = 21 THEN
            isBlackjack = 1
            EXIT FUNCTION
        END IF
    END IF
    isBlackjack = 0
END FUNCTION

' 庄家该不该继续要牌
' Whether the dealer should keep taking cards
FUNCTION dealerHits(v AS INTEGER) AS INTEGER
    IF v < DEALER_STOP THEN
        dealerHits = 1
    ELSE
        dealerHits = 0
    END IF
END FUNCTION

' 比大小
' Compare hands
FUNCTION compare(pv AS INTEGER, dv AS INTEGER) AS INTEGER
    IF pv > 21 THEN
        compare = LOSE
        EXIT FUNCTION
    END IF
    IF dv > 21 THEN
        compare = WIN
        EXIT FUNCTION
    END IF
    IF pv > dv THEN
        compare = WIN
    ELSE
        IF pv < dv THEN
            compare = LOSE
        ELSE
            compare = PUSH
        END IF
    END IF
END FUNCTION

' ══════════════════════════════════════════════════════════════════════════
'  牌堆与发牌
'  Deck and dealing
' ══════════════════════════════════════════════════════════════════════════

SUB shuffle()
    DIM k AS INTEGER
    DIM s AS INTEGER
    k = 0
    WHILE k < DECKN
        deck(k) = k
        k = k + 1
    WEND
    ' Fisher-Yates：从后往前，与随机位置交换
'    Fisher-Yates: from the back forwards, swapping with a random position
    k = DECKN - 1
    WHILE k > 0
        s = ui_math_rand(k + 1)
        tmp = deck(k)
        deck(k) = deck(s)
        deck(s) = tmp
        k = k - 1
    WEND
    di = 0
END SUB

' 发一张（牌不够就重洗 —— 手机上一局打不了那么多轮，但别让它越界）
' Deal one card (reshuffle if the deck runs out -- a phone round never gets that long, but do not let it go out of bounds)
FUNCTION deal() AS INTEGER
    IF di >= DECKN THEN
        shuffle()
    END IF
    deal = deck(di)
    di = di + 1
END FUNCTION

SUB dealRound()
    pn = 0
    dn = 0
    hand(0) = deal()
    hand(12) = deal()
    hand(1) = deal()
    hand(13) = deal()
    pn = 2
    dn = 2
    dealerHidden = 1
    doubled = 0
    result = 0
    phase = PH_PLAY
    IF LANG = 0 THEN msg = "要牌 / 停牌 / 加倍？" ELSE msg = "Hit / Stand / Double?"
    IF isBlackjack(0, pn) = 1 THEN
        settle()
    END IF
END SUB

SUB playerHit()
    IF pn >= MAXCARD THEN
        EXIT SUB
    END IF
    hand(pn) = deal()
    pn = pn + 1
    ui_audio_beep 784, 33   ' 发牌：极短轻音
' Deal: a very short light tone
    IF handValue(0, pn) > 21 THEN
        settle()
    END IF
END SUB

SUB playerStand()
    dealerHidden = 0
    phase = PH_DEALER
END SUB

SUB playerDouble()
    IF chips < bet THEN
        IF LANG = 0 THEN msg = "筹码不够加倍" ELSE msg = "Not enough chips to double"
        ui_audio_beep 131, 99   ' 筹码不够：低闷
' Not enough chips: a low muffled tone
        EXIT SUB
    END IF
    chips = chips - bet
    bet = bet * 2
    doubled = 1
    hand(pn) = deal()
    pn = pn + 1
    ui_audio_beep 1047, 33   ' 加倍发牌
' The extra deal on a double
    playerStand()
END SUB

' 庄家一路要到 17 点
' The dealer keeps taking cards all the way to 17
SUB dealerPlay()
    WHILE dealerHits(handValue(12, dn)) = 1
        IF dn >= MAXCARD THEN
            EXIT WHILE
        END IF
        hand(12 + dn) = deal()
        dn = dn + 1
    WEND
    settle()
END SUB

' 结算
' Settlement
SUB settle()
    DIM pv AS INTEGER
    DIM dv AS INTEGER
    dealerHidden = 0
    pv = handValue(0, pn)
    dv = handValue(12, dn)

    IF isBlackjack(0, pn) = 1 THEN
        IF isBlackjack(12, dn) = 1 THEN
            result = PUSH
        ELSE
            result = WIN
            chips = chips + bet * BJPAY_N / BJPAY_D
        END IF
    ELSE
        result = compare(pv, dv)
        IF result = WIN THEN
            chips = chips + bet
        END IF
        IF result = PUSH THEN
            chips = chips + bet
        END IF
    END IF

    SELECT CASE result
        CASE WIN
            IF LANG = 0 THEN msg = "你赢了！+" + STR$(bet) ELSE msg = "You win! +" + STR$(bet)
            ui_audio_beep 1047, 320   ' 赢：最高音（结局取两端）
' Win: the highest tone (the outcome takes both extremes)
            ui_vibrate_simple(60, 120)
        CASE LOSE
            IF LANG = 0 THEN msg = "庄家赢 " + STR$(pv) + " : " + STR$(dv) ELSE msg = "Dealer wins " + STR$(pv) + " : " + STR$(dv)
            ui_audio_beep 131, 320   ' 输：最低音（结局取两端）
' Lose: the lowest tone (the outcome takes both extremes)
            ui_vibrate_simple(180, 200)
        CASE PUSH
            IF LANG = 0 THEN msg = "和局，退还赌注" ELSE msg = "Draw, bet returned"
            ui_audio_beep 330, 320   ' 和局：中性（既不欢快也不沮丧）
' Push: neutral (neither cheerful nor gloomy)
        CASE ELSE
            IF LANG = 0 THEN msg = "（未结算）" ELSE msg = "(unsettled)"
    END SELECT

    phase = PH_OVER
    IF chips <= 0 THEN
        IF LANG = 0 THEN msg = "筹码输光了 —— 点【重开】再来" ELSE msg = "Out of chips - tap Restart"
    END IF
END SUB

' ══════════════════════════════════════════════════════════════════════════
'  绘制
'  Drawing
' ══════════════════════════════════════════════════════════════════════════

' 点数 → 显示文本
' Rank -> display text
FUNCTION rankText(r AS INTEGER) AS STRING
    SELECT CASE r
        CASE 1
            rankText = "A"
        CASE 11
            rankText = "J"
        CASE 12
            rankText = "Q"
        CASE 13
            rankText = "K"
        CASE ELSE
            rankText = STR$(r)
    END SELECT
END FUNCTION

FUNCTION suitText(s AS INTEGER) AS STRING
    SELECT CASE s
        CASE 0
            suitText = "S"
        CASE 1
            suitText = "H"
        CASE 2
            suitText = "D"
        CASE ELSE
            suitText = "C"
    END SELECT
END FUNCTION

FUNCTION suitColor(s AS INTEGER) AS INTEGER
    IF s = 1 THEN
        suitColor = C_RED
        EXIT FUNCTION
    END IF
    IF s = 2 THEN
        suitColor = C_RED
        EXIT FUNCTION
    END IF
    suitColor = C_DARK
END FUNCTION

' 画一张牌。faceDown=1 时画牌背。
' Draw one card. faceDown=1 draws the back of the card.
SUB drawCard(x AS INTEGER, y AS INTEGER, c AS INTEGER, faceDown AS INTEGER)
    IF faceDown = 1 THEN
        ui_2d_rect(x, y, CARDW, CARDH, C_CARDBK, 1, 0, 7)
        ui_2d_rect(x + 6, y + 6, CARDW - 12, CARDH - 12, C_DARK, 1, 0, 5)
        RETURN
    END IF
    ui_2d_rect(x, y, CARDW, CARDH, C_CARD, 1, 0, 7)
    ui_2d_text(x + 7, y + 6, rankText(rankOf(c)), suitColor(suitOf(c)), 20, VML_ANCHOR_LEFT)
    ui_2d_text(x + CARDW / 2, y + CARDH - 26, suitText(suitOf(c)), suitColor(suitOf(c)), 18, VML_ANCHOR_CENTER)
END SUB

SUB drawHand(off AS INTEGER, n AS INTEGER, y AS INTEGER, hideFirst AS INTEGER)
    DIM k AS INTEGER
    DIM x AS INTEGER
    DIM overlap AS INTEGER
    DIM total AS INTEGER
    DIM startX AS INTEGER

    ' 手牌多了就压着叠 —— 别让它画出屏幕
'    Overlap them when the hand grows -- do not let it draw off screen
    overlap = CARDW + 6
    total = n * overlap
    IF total > sw - 24 THEN
        IF n > 1 THEN
            overlap = (sw - 24) / n
        END IF
    END IF
    total = n * overlap
    startX = (sw - total) / 2
    IF startX < 8 THEN
        startX = 8
    END IF

    k = 0
    WHILE k < n
        x = startX + k * overlap
        IF k = 0 THEN
            IF hideFirst = 1 THEN
                drawCard(x, y, hand(off + k), 1)
            ELSE
                drawCard(x, y, hand(off + k), 0)
            END IF
        ELSE
            drawCard(x, y, hand(off + k), 0)
        END IF
        k = k + 1
    WEND
END SUB

SUB drawHud()
    ui_2d_rect(0, 0, sw, HUDH, C_HUD, 1, 0, 0)
    IF LANG = 0 THEN lb = "筹码" ELSE lb = "Chips"
    ui_2d_text(12, 10, lb, C_DIM, 13, VML_ANCHOR_LEFT)
    ui_2d_text(12, 28, STR$(chips), C_GOLD, 22, VML_ANCHOR_LEFT)
    IF LANG = 0 THEN lb = "赌注" ELSE lb = "Bet"
    ui_2d_text(sw / 2, 10, lb, C_DIM, 13, VML_ANCHOR_CENTER)
    ui_2d_text(sw / 2, 28, STR$(bet), C_GOLD, 22, VML_ANCHOR_CENTER)

    IF phase = PH_PLAY THEN
        txt = "?"
        IF dealerHidden = 0 THEN
            txt = STR$(handValue(12, dn))
        END IF
        IF LANG = 0 THEN lb = "庄家" ELSE lb = "Dealer"
        ui_2d_text(sw - 12, 10, lb, C_DIM, 13, VML_ANCHOR_RIGHT)
        ui_2d_text(sw - 12, 28, txt, C_TEXT, 22, VML_ANCHOR_RIGHT)
    ELSE
        IF LANG = 0 THEN lb = "玩家" ELSE lb = "You"
        ui_2d_text(sw - 12, 10, lb, C_DIM, 13, VML_ANCHOR_RIGHT)
        ui_2d_text(sw - 12, 28, STR$(handValue(0, pn)), C_TEXT, 22, VML_ANCHOR_RIGHT)
    END IF
END SUB

SUB drawTable()
    DIM dealerY AS INTEGER
    DIM playerY AS INTEGER
    dealerY = HUDH + 44
    playerY = sh - 300

    IF LANG = 0 THEN lb = "庄家" ELSE lb = "Dealer"
    ui_2d_text(sw / 2, HUDH + 12, lb, C_DIM, 13, VML_ANCHOR_CENTER)
    drawHand(12, dn, dealerY, dealerHidden)

    IF LANG = 0 THEN lb = "你" ELSE lb = "You"
    ui_2d_text(sw / 2, playerY - 22, lb, C_DIM, 13, VML_ANCHOR_CENTER)
    drawHand(0, pn, playerY, 0)
END SUB

SUB drawButton(x AS INTEGER, y AS INTEGER, w AS INTEGER, label AS STRING, enabled AS INTEGER)
    IF enabled = 1 THEN
        ui_2d_rect(x, y, w, bwh, C_BTN, 1, 0, 12)
    ELSE
        ui_2d_rect(x, y, w, bwh, C_FLAT, 1, 0, 12)
    END IF
    ui_2d_text(x + w / 2, y + 18, label, C_TEXT, 18, VML_ANCHOR_CENTER)
END SUB

SUB drawControls()
    ui_2d_rect(0, ctlY, sw, sh - ctlY, C_HUD, 1, 0, 0)
    ui_2d_rect(0, ctlY, sw, 2, C_FLAT, 1, 0, 0)

    IF phase = PH_BET THEN
        DIM canMinus AS INTEGER
        canMinus = 0
        IF bet > 10 THEN
            canMinus = 1
        END IF
        drawButton(b1x, b1y, bw, "−", canMinus)
        drawButton(b2x, b2y, bw, "+", 1)
        IF LANG = 0 THEN lb = "发 牌" ELSE lb = "Deal"
        drawButton(b3x, b3y, sw - 48, lb, 1)
        RETURN
    END IF

    IF phase = PH_PLAY THEN
        IF LANG = 0 THEN lb = "要牌" ELSE lb = "Hit"
        drawButton(b1x, b1y, bw, lb, 1)
        IF LANG = 0 THEN lb = "停牌" ELSE lb = "Stand"
        drawButton(b2x, b2y, bw, lb, 1)
        DIM canDouble AS INTEGER
        canDouble = 0
        IF chips >= bet THEN
            canDouble = 1
        END IF
        IF pn > 2 THEN
            canDouble = 0
        END IF
        IF LANG = 0 THEN lb = "加倍" ELSE lb = "Double"
        drawButton(b3x, b3y, sw - 48, lb, canDouble)
        RETURN
    END IF

    IF LANG = 0 THEN lb = "重 开" ELSE lb = "Restart"
    drawButton(b1x, b1y, sw - 48, lb, 1)
END SUB

SUB drawScene()
    ui_2d_clear(C_FELT)
    ' 桌面感：中间一道深色带
'    A tabletop feel: a dark band across the middle
    ui_2d_rect(0, sh / 2 - 40, sw, 80, C_FELT_D, 1, 0, 0)
    drawHud()
    drawTable()
    ui_2d_text(sw / 2, ctlY - 30, msg, C_GOLD, 15, VML_ANCHOR_CENTER)
    drawControls()
    ui_2d_present()
END SUB

' ══════════════════════════════════════════════════════════════════════════
'  输入
'  Input
' ══════════════════════════════════════════════════════════════════════════
FUNCTION inRect(x AS INTEGER, y AS INTEGER, w AS INTEGER, h AS INTEGER, px AS INTEGER, py AS INTEGER) AS INTEGER
    DIM ok AS INTEGER
    ok = 0
    IF px >= x THEN
        IF px <= x + w THEN
            IF py >= y THEN
                IF py <= y + h THEN
                    ok = 1
                END IF
            END IF
        END IF
    END IF
    inRect = ok
END FUNCTION

SUB newRound()
    bet = 10
    IF bet > chips THEN
        bet = chips
    END IF
    phase = PH_BET
    IF LANG = 0 THEN msg = "下注 —— 调好赌注点【发牌】" ELSE msg = "Place bet, then tap Deal"
    pn = 0
    dn = 0
END SUB

SUB handlePoint(isDown AS INTEGER)
    IF isDown = 0 THEN
        EXIT SUB
    END IF
    rx = ui_msg_get_a()
    ry = ui_msg_get_b()

    IF phase = PH_BET THEN
        IF inRect(b1x, b1y, bw, bwh, rx, ry) = 1 THEN
            bet = bet - 10
            IF bet < 10 THEN
                bet = 10
            END IF
            IF bet > chips THEN
                bet = chips
            END IF
            ui_audio_beep 262, 33   ' 减注：低一点
' Bet down: a lower tone
            EXIT SUB
        END IF
        IF inRect(b2x, b2y, bw, bwh, rx, ry) = 1 THEN
            bet = bet + 10
            IF bet > chips THEN
                bet = chips
            END IF
            ui_audio_beep 392, 33   ' 加注：高一点（与减注一耳朵分得出）
' Bet up: a higher tone (instantly tellable from bet-down by ear)
            EXIT SUB
        END IF
        IF inRect(b3x, b3y, sw - 48, bwh, rx, ry) = 1 THEN
            IF chips > 0 THEN
                chips = chips - bet
                shuffle()
                dealRound()
                ui_audio_beep 659, 66   ' 洗牌
' Shuffle
            END IF
        END IF
        EXIT SUB
    END IF

    IF phase = PH_PLAY THEN
        IF inRect(b1x, b1y, bw, bwh, rx, ry) = 1 THEN
            playerHit()
            EXIT SUB
        END IF
        IF inRect(b2x, b2y, bw, bwh, rx, ry) = 1 THEN
            playerStand()
            EXIT SUB
        END IF
        IF inRect(b3x, b3y, sw - 48, bwh, rx, ry) = 1 THEN
            IF pn = 2 THEN
                IF chips >= bet THEN
                    playerDouble()
                END IF
            END IF
        END IF
        EXIT SUB
    END IF

    IF phase = PH_OVER THEN
        IF inRect(b1x, b1y, sw - 48, bwh, rx, ry) = 1 THEN
            IF chips <= 0 THEN
                chips = 200
                IF LANG = 0 THEN msg = "重新给你 200 筹码" ELSE msg = "Gave you 200 chips back"
            END IF
            newRound()
            ui_audio_beep 523, 66   ' 新局
' New round
        END IF
    END IF
END SUB

SUB handleKey()
    DIM k AS INTEGER
    k = ui_msg_get_a()
    IF k = 27 THEN
        quit = 1
    END IF
    IF phase = PH_PLAY THEN
        IF k = 72 THEN
            playerHit()
        END IF
        IF k = 83 THEN
            playerStand()
        END IF
        IF k = 68 THEN
            IF pn = 2 THEN
                IF chips >= bet THEN
                    playerDouble()
                END IF
            END IF
        END IF
    END IF
    IF k = 13 THEN
        IF phase = PH_OVER THEN
            IF chips <= 0 THEN
                chips = 200
            END IF
            newRound()
        END IF
        IF phase = PH_BET THEN
            IF chips > 0 THEN
                chips = chips - bet
                shuffle()
                dealRound()
            END IF
        END IF
    END IF
END SUB

' ══════════════════════════════════════════════════════════════════════════
'  主循环
'  Main loop
' ══════════════════════════════════════════════════════════════════════════
SUB runGame()
    ui_scr_set_keep_on(1)

    ctlY = sh - 190
    bwh = 56
    bw = (sw - 72) / 2
    b1x = 24
    b2x = 24 + bw + 24
    b3x = 24
    b1y = ctlY + 20
    b2y = ctlY + 20
    b3y = ctlY + 92

    chips = 200
    newRound()

    WHILE ui_win_is_closed() = 0
        IF quit = 1 THEN
            ui_sfx_panic
            ui_win_close()
        END IF

        mt = ui_msg_fetch_wait(60)
        n = 0
        WHILE mt <> 0
            IF mt = 10 THEN
                quit = 1
            END IF
            IF mt = 1 THEN
                handleKey()
            END IF
            IF mt = 6 THEN
                handlePoint(1)
            END IF
            IF mt = 4 THEN
                handlePoint(1)
            END IF
            IF phase = PH_DEALER THEN
                dealerPlay()
            END IF
            n = n + 1
            IF n >= 40 THEN
                mt = 0
            ELSE
                mt = ui_msg_fetch()
            END IF
        WEND

        drawScene()
    WEND
END SUB

' ══════════════════════════════════════════════════════════════════════════
'  开机自检
'  Startup self-check
' ══════════════════════════════════════════════════════════════════════════
SUB simCheck()
    IF LANG = 0 THEN PRINT "── 21 点 · 规则自检 ──" ELSE PRINT "-- Blackjack - rule self-check --"

    ' 编码往返
'    Encoding round-trip
    IF LANG = 0 THEN PRINT "  牌 30 的点数/花色（应 7 / 2）:"; rankOf(30); suitOf(30) ELSE PRINT "  card 30 rank/suit (want 7 / 2):"; rankOf(30); suitOf(30)

    ' 手牌点数：A 的两面性
'    Hand value: the two faces of an ace
    hand(0) = 1 * 4 + 0
    pn = 1
    IF LANG = 0 THEN PRINT "  单张 A（应 11）:"; handValue(0, pn) ELSE PRINT "  single A (want 11):"; handValue(0, pn)
    hand(1) = 13 * 4 + 0
    pn = 2
    IF LANG = 0 THEN PRINT "  A + K（应 21，天生 21 点应 1）:"; handValue(0, pn); isBlackjack(0, pn) ELSE PRINT "  A + K (want 21; blackjack flag want 1):"; handValue(0, pn); isBlackjack(0, pn)
    hand(1) = 9 * 4 + 0
    pn = 2
    IF LANG = 0 THEN PRINT "  A + 9（应 20）:"; handValue(0, pn) ELSE PRINT "  A + 9 (want 20):"; handValue(0, pn)
    hand(1) = 13 * 4 + 0
    hand(2) = 13 * 4 + 0
    pn = 3
    IF LANG = 0 THEN PRINT "  A + K + K（应 21 —— A 降成 1）:"; handValue(0, pn) ELSE PRINT "  A + K + K (want 21 - A drops to 1):"; handValue(0, pn)
    hand(2) = 5 * 4 + 0
    pn = 3
    IF LANG = 0 THEN PRINT "  A + K + 5（应 16 —— A 仍按 11）:"; handValue(0, pn) ELSE PRINT "  A + K + 5 (want 16 - A stays 11):"; handValue(0, pn)

    ' 爆牌
'    Bust
    hand(0) = 10 * 4 + 0
    hand(1) = 10 * 4 + 0
    hand(2) = 5 * 4 + 0
    pn = 3
    IF LANG = 0 THEN PRINT "  10+10+5（应 25，已爆）:"; handValue(0, pn) ELSE PRINT "  10+10+5 (want 25, bust):"; handValue(0, pn)

    ' 庄家规则
'    Dealer rule
    IF LANG = 0 THEN PRINT "  庄家 16 要不要牌（应 1）:"; dealerHits(16) ELSE PRINT "  dealer hits on 16 (want 1):"; dealerHits(16)
    IF LANG = 0 THEN PRINT "  庄家 17 要不要牌（应 0）:"; dealerHits(17) ELSE PRINT "  dealer hits on 17 (want 0):"; dealerHits(17)
    IF LANG = 0 THEN PRINT "  庄家 21 要不要牌（应 0）:"; dealerHits(21) ELSE PRINT "  dealer hits on 21 (want 0):"; dealerHits(21)

    ' 比大小
'    Compare hands
    IF LANG = 0 THEN PRINT "  玩家 20 庄家 19（应 1=赢）:"; compare(20, 19) ELSE PRINT "  player 20 vs dealer 19 (want 1=win):"; compare(20, 19)
    IF LANG = 0 THEN PRINT "  玩家 18 庄家 19（应 2=输）:"; compare(18, 19) ELSE PRINT "  player 18 vs dealer 19 (want 2=lose):"; compare(18, 19)
    IF LANG = 0 THEN PRINT "  玩家 19 庄家 19（应 3=和）:"; compare(19, 19) ELSE PRINT "  player 19 vs dealer 19 (want 3=push):"; compare(19, 19)
    IF LANG = 0 THEN PRINT "  玩家爆牌 22 庄家 5（应 2=输）:"; compare(22, 5) ELSE PRINT "  player bust 22 vs dealer 5 (want 2=lose):"; compare(22, 5)
    IF LANG = 0 THEN PRINT "  庄家爆牌 22 玩家 5（应 1=赢）:"; compare(5, 22) ELSE PRINT "  dealer bust 22 vs player 5 (want 1=win):"; compare(5, 22)

    ' 发牌不重样：洗一副，前 10 张互不相同
'    Dealing without repeats: shuffle a deck, the first 10 cards are all different
    shuffle()
    DIM dup AS INTEGER
    dup = 0
    i = 0
    WHILE i < 10
        j = i + 1
        WHILE j < 10
            IF deck(i) = deck(j) THEN
                dup = dup + 1
            END IF
            j = j + 1
        WEND
        i = i + 1
    WEND
    IF LANG = 0 THEN PRINT "  洗牌后前 10 张的重复对数（应 0）:"; dup ELSE PRINT "  duplicate pairs in first 10 after shuffle (want 0):"; dup
END SUB

' ══════════════════════════════════════════════════════════════════════════
'  主程序
'  Main program
' ══════════════════════════════════════════════════════════════════════════
' 界面语言：**开局查一次**存进 LANG（ui_scr_get_language 是 syscall，别每帧调）
' UI language: **queried once at startup** and stored in LANG (ui_scr_get_language is a syscall; do not call it every frame)
LANG = ui_scr_get_language()
simCheck()

IF LANG = 0 THEN lb = "21 点" ELSE lb = "Blackjack"
wh = ui_win_open_ex(lb, 0, 0, VML_WIN_PORTRAIT, VML_WIN_NO_GAMEPAD)

sw = ui_scr_get_w()
sh = ui_scr_get_h()
IF sw <= 0 THEN
    sw = 390
END IF
IF sh <= 0 THEN
    sh = 660
END IF

IF wh < 1 THEN
    IF LANG = 0 THEN PRINT "（桌面脚手架：没有真窗口，规则自检打完就退出）" ELSE PRINT "(desktop scaffold: no real window; rule self-check done, exiting)"
ELSE
    runGame()
END IF