From a3078cf1c1b7bf100705f27d03ddb0162e3ea640 Mon Sep 17 00:00:00 2001
From: PlexSheep <PlexSheep@protonmail.com>
Date: Tue, 14 Feb 2023 16:37:35 +0100
Subject: [PATCH] shunting yard works

---
 Cargo.toml                             |  2 +-
 src/expression_parser.rs               |  2 +-
 src/expression_parser/shunting_yard.rs | 51 +++++++++++++++++++-------
 3 files changed, 39 insertions(+), 16 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 39f80cf..f5d1369 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "rust_command_line_calculator"
-version = "0.1.2"
+version = "0.2.0"
 edition = "2021"
 authors = ["Christoph J. Scherr <software@cscherr.de>"]
 license = "GPL3"
diff --git a/src/expression_parser.rs b/src/expression_parser.rs
index 1268f24..79d0e81 100644
--- a/src/expression_parser.rs
+++ b/src/expression_parser.rs
@@ -301,7 +301,7 @@ impl Expression {
         match rpn {
             Ok(valid_rpn) => {
                 dbg!(&valid_rpn);
-                return shunting_yard::calc_reverse_polish_notation(&valid_rpn);
+                return shunting_yard::calc_reverse_polish_notation(valid_rpn);
             },
             Err(err) => {
                 eprintln!("Could not calculate a result for expression '{}': {err}", self.text);
diff --git a/src/expression_parser/shunting_yard.rs b/src/expression_parser/shunting_yard.rs
index bb3d476..ccc03fd 100644
--- a/src/expression_parser/shunting_yard.rs
+++ b/src/expression_parser/shunting_yard.rs
@@ -76,10 +76,13 @@ const EXPONENTIATION: Operator = Operator {
 
 const OPERATORS: [Operator; 5] = [ADDITION, SUBTRACTION, MULTIPLICATION, DIVISION, EXPONENTIATION];
 
-pub fn form_reverse_polish_notation(regular_math: &str) -> Result<String, String> {
-    let mut output_queue: Vec<char> = Vec::new();
+pub fn form_reverse_polish_notation(regular_math: &str) -> Result<Vec<String>, String> {
+    let mut output_queue: Vec<Vec<char>> = Vec::new();
     let mut input_queue: Vec<char> = regular_math.chars().rev().collect();
     let mut operator_stack: Vec<char> = Vec::new();
+    let mut currently_processing_numeric_group = false;
+    let mut current_numeric_group: Vec<char> = Vec::new();
+    let mut current_numeric_group_has_point = false;
 
     // while there are tokens to br read:
     while !(input_queue.is_empty()) {
@@ -89,35 +92,48 @@ pub fn form_reverse_polish_notation(regular_math: &str) -> Result<String, String
             
         // if the token is:
         // a number:
-        if token.is_numeric() {
+        if token.is_numeric() | (token == '.') {
             // put it into the output_queue
-            output_queue.push(token);
+            current_numeric_group.push(token);
+            currently_processing_numeric_group = true;
+            if (token == '.') & (!current_numeric_group_has_point) {
+                current_numeric_group_has_point = true;
+            }
+            else if (token == '.') & (current_numeric_group_has_point) {
+                return Err("Numeric group contains too many '.' Only one is allowed.".to_string());
+            }
         }
         // a function
         // handled by the expression parser
 
         // a operator o1
         else if Operator::is_operator(token) {
+
+            // numeric group is done, push it.
+            if currently_processing_numeric_group {
+                output_queue.push(current_numeric_group);
+                current_numeric_group = Vec::new();
+                currently_processing_numeric_group = false;
+                current_numeric_group_has_point = false;
+            }
+
             // (get the constant Operator (which is a struct) that fits to that token.)
             let o1 = match Operator::get_operator(token) {
                 Some(valid_op) => valid_op,
-                None => {panic!("Operator '{token}' not found.");},
+                None => {panic!("Operator '{}' not found.", token);},
             };
             
             // while there is an operator o2 at the top of the stack 
             if !operator_stack.is_empty() {
-                dbg!(&operator_stack);
                 dbg!(&operator_stack);
                 let o2 = match Operator::get_operator(*(operator_stack.clone().last().clone().unwrap())) {
                     Some(valid_op) => valid_op,
-                    None => {panic!("Operator '{token}' not found.");},
+                None => {panic!("Operator '{}' not found.", token);},
                 };
                 // and
                 // (o2 has greater precedence than o1 or (o1 and o2 have the same precedence and o1
                 // is left associative))
                 while ((operator_stack.last().is_some()) & ((o2.precedence > o1.precedence) | ((o1.precedence == o2.precedence) & (o1.associativity == Associativity::Left)))) {
-                    dbg!(&operator_stack);
-                    println!("REACHED THE MAGIC WHILE");
                     // pop o2 from the operator stack into the output queue.
                     // after this debug statement, the operator_stack is empty for no reason!!!!
                     // FIXME
@@ -125,7 +141,7 @@ pub fn form_reverse_polish_notation(regular_math: &str) -> Result<String, String
                         Some(c) => c,
                         None => {panic!("weirdly gone!")},
                         };
-                    output_queue.push(my_c);
+                    output_queue.push(vec![my_c]);
                 }
             }
             operator_stack.push(o1.character);
@@ -140,22 +156,29 @@ pub fn form_reverse_polish_notation(regular_math: &str) -> Result<String, String
         }
         */
         else {
-            return Err("Unrecognized token: '{token}'".to_string());
+            return Err(("Unrecognized token: '".to_string() + token.to_string().as_str() + "'").to_string());
         }
     }
+    // numeric group is done, push it.
+    if currently_processing_numeric_group {
+        output_queue.push(current_numeric_group);
+    }
     dbg!(&output_queue);
 
     // afterwards, process any operators still on the operator_stack
     while !(operator_stack.is_empty()) {
-        output_queue.push(operator_stack.pop().unwrap());
+        output_queue.push(vec![operator_stack.pop().unwrap()]);
     }
 
     dbg!(&output_queue);
-    let rpn: String = output_queue.iter().cloned().collect::<String>();
+    let mut rpn: Vec<String> = Vec::new();
+    for group in output_queue {
+        rpn.push(group.iter().cloned().collect::<String>());
+    }
     Ok(rpn)
 }
 
 // after we have the rpn, we may want to calculate the values with it.
-pub fn calc_reverse_polish_notation(rpn: &str) -> Result<f64, String> {
+pub fn calc_reverse_polish_notation(rpn: Vec<String>) -> Result<f64, String> {
     Ok(0.0)
 }