From a40d4c3410a86c82e7045d2750dbde50c10e9923 Mon Sep 17 00:00:00 2001
From: Akemi Izuko <akemi@noway.moe>
Date: Sat, 18 Nov 2023 00:15:19 -0700
Subject: [PATCH] AstBuilder: binary op for integers

---
 src/ast/expr.rs    |  2 +-
 src/ast_builder.rs | 36 +++++++++++++++++++++++++++++++++++-
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/src/ast/expr.rs b/src/ast/expr.rs
index c8180df..48f7908 100644
--- a/src/ast/expr.rs
+++ b/src/ast/expr.rs
@@ -135,7 +135,7 @@ impl BinaryOperator {
         }
     }
 
-    pub fn sub(left: Expr, right: Expr) -> Self {
+    pub fn subtract(left: Expr, right: Expr) -> Self {
         let is_both_same = left.get_base() == right.get_base();
         let is_one_real = left.get_base() == BaseType::Real || right.get_base() == BaseType::Real;
         let is_one_int = left.get_base() == BaseType::Int || right.get_base() == BaseType::Int;
diff --git a/src/ast_builder.rs b/src/ast_builder.rs
index eed232e..d55bf9f 100644
--- a/src/ast_builder.rs
+++ b/src/ast_builder.rs
@@ -6,12 +6,18 @@ use std::collections::HashMap;
 use crate::params::Params;
 use crate::ast::*;
 
+#[derive(Default)]
+struct StateTracking {
+    int_recursion_depth: u32,
+}
+
 pub struct AstBuilder {
     params: Params,
     ast: GlobalBlock,
     name_counter: u64,
     typedef_map: HashMap<BaseType, Vec<String>>,
     typedef_vec: Vec<(String, BaseType)>,
+    state: StateTracking,
     // Random generation
     rng: rand::rngs::ThreadRng,
     rng_float: FloatGenerator,
@@ -33,6 +39,7 @@ impl AstBuilder {
             name_counter: 0,
             typedef_map,
             typedef_vec,
+            state: StateTracking::default(),
             rng: rand::thread_rng(),
             rng_float: FloatGenerator::new(&params),
             rng_int: IntGenerator::new(&params),
@@ -119,7 +126,34 @@ impl AstBuilder {
     }
 
     fn gen_integer(&mut self) -> Expr {
-        Expr::new_literal(self.gen_literal(BaseType::Int))
+        let p: f64 = self.rng.gen();
+        let mut ps = &self.params.types.gen_integer;
+
+        self.state.int_recursion_depth += 1;
+
+        if p < ps.get_instant || self.state.int_recursion_depth >= ps.max_depth {
+            self.state.int_recursion_depth -= 1;
+            return Expr::new_literal(self.gen_literal(BaseType::Int));
+        }
+
+        let lhs = self.gen_integer();
+        let rhs = self.gen_integer();
+        self.state.int_recursion_depth -= 1;
+
+        ps = &self.params.types.gen_integer;
+
+        if p < ps.get_instant + ps.expr_add {
+            Expr::new_binary_op(BinaryOperator::add(lhs, rhs))
+        } else if p < ps.get_instant + ps.expr_add + ps.expr_sub {
+            Expr::new_binary_op(BinaryOperator::subtract(lhs, rhs))
+        } else if p < ps.get_instant + ps.expr_add + ps.expr_sub + ps.expr_mul {
+            Expr::new_binary_op(BinaryOperator::multiply(lhs, rhs))
+        } else if p < ps.get_instant + ps.expr_add + ps.expr_sub + ps.expr_mul + ps.expr_div {
+            Expr::new_binary_op(BinaryOperator::divide(lhs, rhs))
+        } else {
+            Expr::new_literal(self.gen_literal(BaseType::Int))  // TODO: this shouldn't be here
+        }
+
     }
 
     fn gen_real(&mut self) -> Expr {