From 477b98d8d271dafdbf4b02137a9068c70637c466 Mon Sep 17 00:00:00 2001
From: littleblack111 <littleblack11111@gmail.com>
Date: Sat, 27 Sep 2025 20:35:59 +0800
Subject: feat: ast

---
 src/ast.rs | 53 ++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 48 insertions(+), 5 deletions(-)

(limited to 'src/ast.rs')

diff --git a/src/ast.rs b/src/ast.rs
index 9777d4e..a87b6a2 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -1,17 +1,18 @@
-use crate::parser::{self, Expr, ExprT, Scope};
+use crate::parser::{Expr, ExprT, Metadata, Scope};
 
+#[derive(Clone, Debug)]
 pub enum DepthExpr<'a> {
     Decision {
         cond: Box<DepthExpr<'a>>,
         t: Scope,
-        else_branch: Option<Box<DepthExpr<'a>>>,
+        else_branch: Option<Box<Vec<DepthExpr<'a>>>>,
     },
     IO(&'a str),
     Process(&'a str),
 }
 
-fn parse(vec: Vec<Expr>) -> Vec<DepthExpr> {
-    let exprs = Vec::new();
+pub fn parse<'a, 'b>(vec: &'b Vec<Expr<'a>>) -> Vec<DepthExpr<'a>> {
+    let mut exprs: Vec<DepthExpr<'a>> = Vec::new();
 
     let mut it = vec
         .iter()
@@ -19,8 +20,50 @@ fn parse(vec: Vec<Expr>) -> Vec<DepthExpr> {
 
     while let Some(e) = it.next() {
         if let ExprT::Decision((cond, scope)) = e.expr {
-            let cond = parser::parse(cond);
+            let cond = DepthExpr::Process(cond);
+            for e in it.clone() {
+                if e.meta == Some(Metadata::EndScope) {
+                    break;
+                }
+            }
+
+            exprs.push(DepthExpr::Decision {
+                cond: Box::new(cond),
+                t: scope,
+                else_branch: Some(Box::new(parse(&entire_scopes(
+                    it.clone()
+                        .cloned(),
+                )))),
+            });
+        }
+    }
+
+    exprs
+}
+
+fn entire_scopes<'a>(it: impl Iterator<Item = Expr<'a>>) -> Vec<Expr<'a>> {
+    let mut exprs: Vec<Expr<'a>> = Vec::new();
+    let mut scope_count: u32 = 1; // assume we already entered the scope
+
+    for i in it {
+        if scope_count == 0 {
+            break;
+        }
+        if let Some(meta) = i.meta {
+            match meta {
+                Metadata::StartScope => {
+                    scope_count = scope_count
+                        .checked_add(1)
+                        .expect("Scopes nested too deep")
+                }
+                Metadata::EndScope => {
+                    scope_count = scope_count
+                        .checked_sub(1)
+                        .expect("Closed not opened scope")
+                }
+            }
         }
+        exprs.push(i);
     }
 
     exprs
-- 
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