Fix opposite_eq method.

Simplify method in Simplify trait.

Fix distributive law.

Response for the simplify endpoint.

HTTP client.

camelCase and SCREAMING_SNAKE_CASE for struct and enum

http/common.js

@@ -0,0 +1,8 @@
+/**
+ * Encode the given string as a URI component, and set the request variable "expression" to the result.
+ * @param {string} expression
+ * @returns {void}
+ */
+export function expression(expression) {
+    request.variables.set("expression", encodeURIComponent(expression))
+}

http/http-client.env.json

@@ -0,0 +1,10 @@
+{
+  "dev": {
+    "expression": "",
+    "url": "http://localhost:8000"
+  },
+  "prod": {
+    "expression": "",
+    "url": "https://api.martials.no/simplify-truths"
+  }
+}

http/simplify.http

@@ -0,0 +1,29 @@
+### GET Atomic Expression
+GET {{url}}/simplify/A
+
+### GET And Expression
+< {%
+    import {expression} from './common.js';
+
+    expression("A & B")
+%}
+GET {{url}}/simplify/{{expression}}
+
+### GET Or Expression
+< {%
+    import {expression} from "./common";
+
+    expression("A | B")
+%}
+GET {{url}}/simplify/{{expression}}
+
+### GET Not Expression
+GET {{url}}/simplify/!A
+
+### GET Implication Expression
+< {%
+    import {expression} from "./common";
+
+    expression("A => B")
+%}
+GET {{url}}/simplify/{{expression}}

src/expressions/expression.rs

@@ -1,4 +1,5 @@
 use std::fmt::Display;
+use serde::{Deserialize, Serialize};
 
 use crate::expressions::operator::BinaryOperator;
 use crate::parsing::expression_parser::parse_expression;
@@ -7,7 +8,8 @@ pub trait OppositeEq {
     fn opposite_eq(&self, other: &Self) -> bool;
 }
 
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
 pub enum Expression {
     Not(Box<Expression>),
     Binary(Box<Expression>, BinaryOperator, Box<Expression>),
@@ -40,8 +42,8 @@ impl OppositeEq for Expression {
     fn opposite_eq(&self, other: &Self) -> bool {
         match (self, other) {
             (Expression::Not(_), Expression::Not(_)) => false,
-            (Expression::Not(_), _) => true,
-            (_, Expression::Not(_)) => true,
+            (Expression::Not(left), right) => left.as_ref() == right,
+            (left, Expression::Not(right)) => left == right.as_ref(),
             _ => false,
         }
     }

src/expressions/operator.rs

@@ -1,17 +1,9 @@
-#[derive(Debug, Copy, Clone, PartialEq)]
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Copy, Clone, PartialEq, Deserialize, Serialize)]
+#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
 pub enum BinaryOperator {
     Implication,
     Or,
     And,
 }
-
-impl From<BinaryOperator> for &str {
-    fn from(op: BinaryOperator) -> Self {
-        match op {
-            BinaryOperator::Implication => "=>",
-            BinaryOperator::Or => "|",
-            BinaryOperator::And => "&",
-        }
-    }
-}
-

src/expressions/simplify.rs

@@ -2,6 +2,7 @@ use crate::expressions::expression::{Expression, OppositeEq};
 use crate::expressions::operator::BinaryOperator;
 
 pub trait Simplify {
+    fn simplify(&self) -> Self;
     fn elimination_of_implication(&self) -> Self;
     fn double_negation_elimination(&self) -> Self;
     fn de_morgans_laws(&self) -> Self;
@@ -12,6 +13,16 @@ pub trait Simplify {
 }
 
 impl Simplify for Expression {
+    // TODO test and define order of operations
+    fn simplify(&self) -> Self {
+        self.elimination_of_implication()
+            .de_morgans_laws()
+            .absorption_law()
+            // .associative_law()
+            .distribution_law()
+            .double_negation_elimination()
+        // .commutative_law()
+    }
     /// Eliminate the implication operator from the expression.
     /// This is done by replacing `a ➔ b` with `¬a ⋁ b`.
     fn elimination_of_implication(&self) -> Self {
@@ -194,7 +205,7 @@ impl Simplify for Expression {
                 let right = right.distribution_law();
                 binary!(left, *operator, right)
             }
-            Expression::Not(expr) => expr.distribution_law(),
+            Expression::Not(expr) => not!(expr.distribution_law()),
             atomic => atomic.clone(),
         }
     }
@@ -208,6 +219,18 @@ impl Simplify for Expression {
 mod tests {
     use crate::expressions::simplify::Simplify;
 
+    #[test]
+    fn test_simplify() {
+        let expression = eval!("a" => "b").simplify();
+        assert_eq!(expression, or!(not!(atomic!("a")), atomic!("b")));
+    }
+
+    #[test]
+    fn test_implication_and_de_morgans() {
+        let expression = implies!(and!(not!(atomic!("a")), atomic!("b")), atomic!("c")).simplify();
+        assert_eq!(expression, or!(or!(atomic!("a"), not!(atomic!("b"))), atomic!("c")));
+    }
+
     #[test]
     fn test_elimination_of_implication() {
         let expression = eval!("a" => "b").elimination_of_implication();
@@ -349,4 +372,10 @@ mod tests {
         let expression = or!(atomic!("a"), and!(atomic!("b"), atomic!("c"))).distribution_law();
         assert_eq!(expression, and!(or!(atomic!("a"), atomic!("b")), or!(atomic!("a"), atomic!("c"))));
     }
+
+    #[test]
+    fn test_distributive_law_nested_not() {
+        let expression = and!(atomic!("a"), not!(or!(atomic!("b"), atomic!("c")))).distribution_law();
+        assert_eq!(expression, and!(atomic!("a"), not!(or!(atomic!("b"), atomic!("c")))))
+    }
 }

src/routing/simplify.rs

@@ -1,7 +1,11 @@
-use axum::{Router, routing::get};
+use axum::{Json, Router, routing::get};
 use axum::extract::{Path, Query};
-use serde::Deserialize;
+use axum::http::StatusCode;
+use axum::response::{IntoResponse, Response};
+use serde::{Deserialize, Serialize};
 
+use crate::expressions::expression::Expression;
+use crate::expressions::simplify::Simplify;
 use crate::language::{AcceptLanguage, Language};
 
 pub fn router() -> Router<()> {
@@ -23,13 +27,32 @@ struct QueryOptions {
     lang: Language,
     #[serde(default = "default_true")]
     simplify: bool,
-    #[serde(default)]
+    #[serde(default = "default_true")]
     case_sensitive: bool,
 }
 
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct SimplifyResponse {
+    before: String,
+    after: String,
+    order_of_operations: Vec<String>,
+    expression: Expression,
+}
+
 // TODO
-async fn simplify(Path(path): Path<String>, query: Query<QueryOptions>, accept_language: Option<AcceptLanguage>) -> String {
-    format!("Path: {}, Query: {:?}, Accept-language header: {:?}", path, query, accept_language)
+async fn simplify(Path(path): Path<String>, query: Query<QueryOptions>, accept_language: Option<AcceptLanguage>) -> Response {
+    if let Ok(expression) = Expression::try_from(path.as_str()) {
+        let simplified = expression.simplify();
+        Json(SimplifyResponse {
+            before: expression.to_string(),
+            after: simplified.to_string(),
+            order_of_operations: vec![], // TODO
+            expression: simplified,
+        }).into_response()
+    } else {
+        (StatusCode::BAD_REQUEST, "Invalid expression").into_response()
+    }
 }
 
 async fn simplify_and_table() {