From a1ae14934b7320a857f4d508b79b5ff33938b000 Mon Sep 17 00:00:00 2001
From: Akemi Izuko <akemi@noway.moe>
Date: Sat, 18 Nov 2023 00:28:55 -0700
Subject: [PATCH] AstBuilder: operators for reals

---
 params.toml        | 15 ++++++++-------
 src/ast_builder.rs | 34 ++++++++++++++++++++++++++++++++--
 src/params.rs      |  1 +
 3 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/params.toml b/params.toml
index bf48c3c..a9c872f 100644
--- a/params.toml
+++ b/params.toml
@@ -74,20 +74,21 @@
         expr_neg = 0.0
 
         get_instant = 0.4
-        max_depth = 20
+        max_depth = 10
 
     [types.gen_real]
-        expr_add = 0.0
-        expr_sub = 0.0
-        expr_mul = 0.0
-        expr_div = 0.0
+        expr_add = 0.1
+        expr_sub = 0.1
+        expr_mul = 0.1
+        expr_div = 0.3
         expr_rem = 0.0
         expr_exp = 0.0
         expr_pos = 0.0
         expr_neg = 0.0
 
-        gen_integer = 0.0
-        get_instant = 0.0
+        gen_integer = 0.1
+        get_instant = 0.3
+        max_depth = 10
 
     [types.gen_tuple]
         gen_each_field = 0.5
diff --git a/src/ast_builder.rs b/src/ast_builder.rs
index d55bf9f..5ba676e 100644
--- a/src/ast_builder.rs
+++ b/src/ast_builder.rs
@@ -9,6 +9,7 @@ use crate::ast::*;
 #[derive(Default)]
 struct StateTracking {
     int_recursion_depth: u32,
+    real_recursion_depth: u32,
 }
 
 pub struct AstBuilder {
@@ -153,11 +154,40 @@ impl AstBuilder {
         } else {
             Expr::new_literal(self.gen_literal(BaseType::Int))  // TODO: this shouldn't be here
         }
-
     }
 
     fn gen_real(&mut self) -> Expr {
-        Expr::new_literal(self.gen_literal(BaseType::Real))
+        let p: f64 = self.rng.gen();
+        let mut ps = &self.params.types.gen_real;
+
+        self.state.real_recursion_depth += 1;
+
+        if p < ps.get_instant || self.state.real_recursion_depth >= ps.max_depth {
+            self.state.real_recursion_depth -= 1;
+            return Expr::new_literal(self.gen_literal(BaseType::Real));
+        } else if p < ps.get_instant + ps.gen_integer {
+            self.state.real_recursion_depth -= 1;
+            return self.gen_integer();
+        }
+
+        let lhs = self.gen_real();
+        let rhs = self.gen_real();
+        self.state.real_recursion_depth -= 1;
+
+        ps = &self.params.types.gen_real;
+        let prevp = ps.get_instant + ps.gen_integer;
+
+        if p < prevp + ps.expr_add {
+            Expr::new_binary_op(BinaryOperator::add(lhs, rhs))
+        } else if p < prevp + ps.expr_add + ps.expr_sub {
+            Expr::new_binary_op(BinaryOperator::subtract(lhs, rhs))
+        } else if p < prevp + ps.expr_add + ps.expr_sub + ps.expr_mul {
+            Expr::new_binary_op(BinaryOperator::multiply(lhs, rhs))
+        } else if p < prevp + 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::Real))  // TODO: this shouldn't be here
+        }
     }
 
     fn gen_literal(&mut self, t: BaseType) -> Literal {
diff --git a/src/params.rs b/src/params.rs
index 78281a5..a9fc2da 100644
--- a/src/params.rs
+++ b/src/params.rs
@@ -148,6 +148,7 @@ toml_struct!{
         expr_neg: f64,
         gen_integer: f64,
         get_instant: f64,
+        max_depth: u32,
     }
 }