feat: add new reroll modifiers for enhanced dice functionality

5 files changed, 42 insertions, 1 deletions

diff --git a/README.md b/README.md
index 771fb9a..8b3c409 100644
--- a/README.md
+++ b/README.md
@@ -94,6 +94,8 @@ python -m oneroll --tui
 - `u` - 去重: `4d6u` (相同点数只计一次)
 - `s` - 排序（不改变总和）: `5d6s`
 - `cV` - 计数值V出现次数（作为一个结果输出）: `5d6c6`
+- `RX` - 直到重投（直至 > X，含安全上限）: `d20R10`
+- `aX` - 重投并相加（若 ≤ X 则再掷并加到结果）: `4d6a2`
 
 ### 复合表达式
 - `6d6dl2kh3` - 丢弃最低2个，然后取最高3个
diff --git a/src/calculator.rs b/src/calculator.rs
index 5376f76..07518b0 100644
--- a/src/calculator.rs
+++ b/src/calculator.rs
@@ -45,7 +45,7 @@ impl DiceCalculator {
                 }
             }
             
-            // handle reroll
+            // handle reroll variants
             for modifier in &dice.modifiers {
                 match modifier {
                     DiceModifier::Reroll(threshold) => {
@@ -60,6 +60,27 @@ impl DiceCalculator {
                             final_rolls[pos] = new_roll as i32;
                         }
                     }
+                    DiceModifier::RerollUntil(threshold) => {
+                        // keep rolling until > threshold (safety cap)
+                        let mut current = *final_rolls.last().unwrap_or(&((roll) as i32));
+                        let mut attempts = 0;
+                        const MAX_ATTEMPTS: usize = 100;
+                        while current <= *threshold && attempts < MAX_ATTEMPTS {
+                            let new_roll = rand::random::<u32>() % dice.sides as u32 + 1;
+                            current = new_roll as i32;
+                            final_rolls = vec![current];
+                            attempts += 1;
+                        }
+                    }
+                    DiceModifier::RerollAndAdd(threshold) => {
+                        // if <= threshold, roll again and add to the last value
+                        if final_rolls.iter().any(|&r| r <= *threshold) {
+                            let new_roll = rand::random::<u32>() % dice.sides as u32 + 1;
+                            let mut sum = final_rolls.iter().sum::<i32>();
+                            sum += new_roll as i32;
+                            final_rolls = vec![sum];
+                        }
+                    }
                     _ => {}
                 }
             }
@@ -246,6 +267,8 @@ impl DiceCalculator {
                 DiceModifier::ExplodeKeepHigh(n) => result.push_str(&format!("K{}", n)),
                 DiceModifier::Reroll(n) => result.push_str(&format!("r{}", n)),
                 DiceModifier::RerollOnce(n) => result.push_str(&format!("ro{}", n)),
+                DiceModifier::RerollUntil(n) => result.push_str(&format!("R{}", n)),
+                DiceModifier::RerollAndAdd(n) => result.push_str(&format!("a{}", n)),
                 DiceModifier::KeepAlias(n) => result.push_str(&format!("k{}", n)),
                 DiceModifier::KeepHigh(n) => result.push_str(&format!("kh{}", n)),
                 DiceModifier::KeepLow(n) => result.push_str(&format!("kl{}", n)),
diff --git a/src/oneroll/grammar.pest b/src/oneroll/grammar.pest
index 09b86f8..006be64 100644
--- a/src/oneroll/grammar.pest
+++ b/src/oneroll/grammar.pest
@@ -26,6 +26,8 @@ modifier = {
     | explode_keep_high
     | reroll
     | reroll_once
+    | reroll_until
+    | reroll_add
     | keep_alias
     | keep_high
     | keep_low
@@ -41,6 +43,8 @@ explode_alias = { "e" }
 explode_keep_high = { "K" ~ number }
 reroll = { "r" ~ number }
 reroll_once = { "ro" ~ number }
+reroll_until = { "R" ~ number }
+reroll_add = { "a" ~ number }
 keep_alias = { "k" ~ number }
 keep_high = { "kh" ~ number }
 keep_low = { "kl" ~ number }
diff --git a/src/parser.rs b/src/parser.rs
index 50231c0..20cd992 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -126,6 +126,16 @@ impl DiceParser {
                             .map_err(|_| DiceError::ParseError("无效的条件重投数值".to_string()))?;
                         Ok(DiceModifier::RerollOnce(num))
                     }
+                    Rule::reroll_until => {
+                        let num = inner.into_inner().next().unwrap().as_str().parse::<i32>()
+                            .map_err(|_| DiceError::ParseError("无效的直到重投数值".to_string()))?;
+                        Ok(DiceModifier::RerollUntil(num))
+                    }
+                    Rule::reroll_add => {
+                        let num = inner.into_inner().next().unwrap().as_str().parse::<i32>()
+                            .map_err(|_| DiceError::ParseError("无效的重投并相加数值".to_string()))?;
+                        Ok(DiceModifier::RerollAndAdd(num))
+                    }
                     Rule::keep_alias => {
                         let num = inner.into_inner().next().unwrap().as_str().parse::<i32>()
                             .map_err(|_| DiceError::ParseError("无效的取高数值".to_string()))?;
diff --git a/src/types.rs b/src/types.rs
index aad0080..1d5d369 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -24,6 +24,8 @@ pub enum DiceModifier {
     ExplodeKeepHigh(i32), // KX == explode then keep high X
     Reroll(i32),       // rX
     RerollOnce(i32),   // roX
+    RerollUntil(i32),  // RX (until > X; with cap)
+    RerollAndAdd(i32), // aX (reroll if <= X and add)
     KeepAlias(i32),    // kX == khX
     KeepHigh(i32),     // khX
     KeepLow(i32),      // klX