PineScript策略求助：入场后无法固定止损与止盈值

我开发了一套融合MACD、HMA和布林带（BB）指标的交易策略，规则如下：

• 多头入场时，止损设为入场前最近7根K线的最低低点，止盈计算公式为入场价格 + 1.5*(入场价格 - 最低低点)
• 空头入场时，止损设为入场前最近7根K线的最高高点，止盈计算公式为入场价格 - 1.5*(最高高点 - 入场价格)

当前核心问题：持仓过程中，止损和止盈的数值会随K线更新而变动，无法固定在入场时的计算值。我尝试用strategy.position标记持仓状态来解决，但未成功。由于刚接触PineScript，可能代码存在逻辑疏漏，希望能帮忙排查修复。

strategy("自定义策略", overlay=true, initial_capital=1000, default_qty_type=strategy.percent_of_equity, default_qty_value=1.5)
// 输入参数
lengthBB = 200
multBB1 = 1.2
multBB2 = 2.0
lengthHMA = 22
lengthMACD = 12
signalMACD = 26
lengthATR = 14
riskToRewardRatio = 1.5
maxBars = 10

// 布林带计算
basisBB1 = ta.sma(close, lengthBB)
upperBB1 = basisBB1 + multBB1 * ta.stdev(close, lengthBB)
lowerBB1 = basisBB1 - multBB1 * ta.stdev(close, lengthBB)
basisBB2 = ta.sma(close, lengthBB)
upperBB2 = basisBB2 + multBB2 * ta.stdev(close, lengthBB)
lowerBB2 = basisBB2 - multBB2 * ta.stdev(close, lengthBB)

// 赫尔移动平均线（HMA）
hmaClose = ta.hma(close, 22)

// MACD指标计算
[macdLine, signalLine, _] = ta.macd(close, lengthMACD, signalMACD, 9)

// ATR指标
atrValue = ta.atr(lengthATR)

// 入场条件
longCondition = (close <= lowerBB1 or close >= upperBB2) and ta.crossover(macdLine, signalLine) and close >= hmaClose
shortCondition = (close > upperBB1 or close < lowerBB2) and ta.crossunder(macdLine, signalLine) and close <= hmaClose

// 按每笔1.5%风险计算仓位
riskPerTrade = strategy.equity * 0.015
positionSize = riskPerTrade / atrValue  

// 计算当前周期的止损止盈（未固定入场值）
stoplossshort = ta.highest(high, 7)
stoplosslong  = ta.lowest(low, 7)
takeProfitLevelLong = close + riskToRewardRatio * (close - ta.lowest(low, 7))
takeProfitLevelShort = close - riskToRewardRatio * (ta.highest(high, 7) - close)

// 用于存储入场时的止损止盈值（var声明实现持久化）
var float stoplossshort1 = na
var float stoplosslong1 = na
var float takeProfitLevelLong1 = na
var float takeProfitLevelShort1= na

// 原逻辑：无入场信号时更新止损止盈值（错误逻辑）
if (longCondition == false and shortCondition == false)
    stoplossshort1 := stoplossshort
    stoplosslong1 := stoplosslong
    takeProfitLevelLong1 := takeProfitLevelLong
    takeProfitLevelShort1 := takeProfitLevelShort

// 多单入场
strategy.entry("多单", strategy.long, qty = positionSize, when = longCondition)
// 空单入场
strategy.entry("空单", strategy.short, qty = positionSize, when = shortCondition)

// 多单平仓条件
if (close <= stoplosslong1 or close >= takeProfitLevelLong1)
    strategy.close("多单")

// 空单平仓条件
if (close >= stoplossshort1 or close <= takeProfitLevelShort1)
    strategy.close("空单")

// 绘制布林带
plot(upperBB1, color=color.red)
plot(lowerBB1, color=color.green)
plot(upperBB2, color=color.red)
plot(lowerBB2, color=color.green)

// 绘制HMA均线
plot(hmaClose, color=color.blue)

// 绘制止损止盈线
plot(stoplosslong1, color=color.red, linewidth=2, title="多单止损")
plot(stoplossshort1, color=color.green, linewidth=2, title="空单止损")
plot(takeProfitLevelLong1, color=color.rgb(175, 76, 76), linewidth=2, title="多单止盈")
plot(takeProfitLevelShort1, color=color.rgb(82, 255, 111), linewidth=2, title="空单止盈")

我曾尝试通过strategy.position设置持仓状态布尔值来固定入场时的止损止盈，但没成功。刚学PineScript，可能哪里写错了。

内容的提问来源于stack exchange，提问作者xtttt