1 files changed, 77 insertions, 0 deletions

diff --git a/src/commands/math.rs b/src/commands/math.rs
new file mode 100644
index 0000000..43a7de8
--- /dev/null
+++ b/src/commands/math.rs
@@ -0,0 +1,77 @@
+use crate::lang;
+use crate::Data;
+use crate::error::{Error, Result};
+
+type Context<'a> = poise::Context<'a, Data, Error>;
+
+/// Evaluate a math expression via qalc
+#[poise::command(slash_command)]
+pub async fn math(
+    ctx: Context<'_>,
+    #[description = "Ekspresja matematyczn"] equation: String,
+) -> Result<()> {
+    if equation.len() > 1000 {
+        ctx.say(lang::L_MATH_TOO_LONG).await?;
+        return Ok(());
+    }
+
+    if !equation.is_ascii() {
+        ctx.say(lang::L_MATH_NOT_ASCII).await?;
+        return Ok(());
+    }
+
+    let mut depth = 0i32;
+    for c in equation.chars() {
+        match c {
+            '(' | '[' | '{' => depth += 1,
+            ')' | ']' | '}' => depth -= 1,
+            _ => {}
+        }
+        if depth < 0 {
+            ctx.say(lang::L_MATH_UNBALANCED).await?;
+            return Ok(());
+        }
+    }
+    if depth != 0 {
+        ctx.say(lang::L_MATH_UNBALANCED).await?;
+        return Ok(());
+    }
+
+    let dangerous = [
+        "eval",
+        "exec",
+        "os.",
+        "subprocess",
+        "import",
+        "__",
+        "system",
+        "shutil",
+        "typecast",
+        "shell",
+        "fork",
+        "execve",
+    ];
+    let lower = equation.to_lowercase();
+    if dangerous.iter().any(|d| lower.contains(d)) {
+        ctx.say(lang::L_MATH_DANGEROUS).await?;
+        return Ok(());
+    }
+
+    let output = tokio::process::Command::new("qalc")
+        .arg(&equation)
+        .output()
+        .await
+        .map_err(|e| Error::Custom(lang::fmt_math_qalc_err(&e)))?;
+
+    let result = String::from_utf8_lossy(&output.stdout).trim().to_string();
+    if result.is_empty() {
+        ctx.say(lang::L_MATH_NO_RESULT).await?;
+    } else {
+        ctx.say(lang::fmt_math_result(&result)).await?;
+    }
+    Ok(())
+}
+
+pub fn commands() -> Vec<poise::Command<Data, Error>> {
+    vec![math()]
+}