making some horrifyingly cursed progress

src/main.rs

@@ -1,27 +1,141 @@
 use std::{
+    collections::HashMap,
     io::{BufRead, BufReader, Write},
-    net::TcpListener,
+    net::{TcpListener, TcpStream},
 };
 
+const VALID_METHODS: [&str; 8] = [
+    "GET", "HEAD", "POST", "PUT", "DELETE", "CONNECT", "OPTIONS", "TRACE",
+];
+
+#[derive(Debug)]
+struct StartLine {
+    method: String,
+    target: String,
+    version: String,
+}
+
+impl StartLine {
+    pub fn new(input: String) -> Self {
+        let input_array = input.trim().split(" ").collect::<Vec<&str>>();
+
+        Self {
+            method: input_array[0].to_owned(),
+            target: input_array[1].to_owned(),
+            version: input_array[2].to_owned(),
+        }
+    }
+
+    pub fn is_valid_method(input: &StartLine) -> bool {
+        if input.method.is_empty() {
+            return false;
+        }
+        let method: &str = input.method.as_str();
+
+        if VALID_METHODS.contains(&method) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+}
+
+fn handle_request(mut stream: TcpStream) {
+    let mut reader = BufReader::new(&mut stream);
+
+    let mut start_line = String::new();
+    reader.read_line(&mut start_line).unwrap();
+
+    // I will not support ignoring the CR
+    if !start_line.ends_with("\r\n") {
+        stream
+            .write_all(b"HTTP/1.1 400 Bad Request\r\n\r\nLines must end with CRLF")
+            .unwrap();
+        return;
+    }
+
+    // Request can have one or many empty lines preceding the request-line and I will ignore these
+    loop {
+        if !start_line.trim().is_empty() {
+            break;
+        }
+        reader.read_line(&mut start_line).unwrap();
+    }
+
+    if start_line.trim().is_empty() {
+        reader.read_line(&mut start_line).unwrap();
+    }
+    if start_line.trim().is_empty() {
+        stream
+            .write_all(b"HTTP/1.1 400 Bad Request\r\n\r\nReceived too many preceding empty lines")
+            .unwrap();
+        return;
+    }
+
+    let start_line = StartLine::new(start_line);
+    dbg!(&start_line);
+
+    if !StartLine::is_valid_method(&start_line) {
+        stream
+            .write_all(b"HTTP/1.1 400 Bad Request\r\n\r\nInvalid request method")
+            .unwrap();
+        return;
+    }
+
+    if start_line.method != "GET" {
+        stream
+            .write_all(b"HTTP/1.1 501 Not Implemented\r\n\r\nServer currently only supports GET")
+            .unwrap();
+        return;
+    }
+
+    let mut is_first_line = true;
+    let mut field_lines: HashMap<String, String> = HashMap::new();
+
+    loop {
+        let mut line = String::new();
+        reader.read_line(&mut line).unwrap();
+        print!("{line}");
+
+        if line.starts_with(" ") {
+            if !is_first_line {
+                continue;
+            }
+            stream
+                .write_all(b"HTTP/1.1 400 Bad Request\r\n\r\nCannot have whitespace between the start-line and field-lines")
+                .unwrap();
+            return;
+        }
+
+        if !line.ends_with("\r\n") {
+            stream
+                .write_all(b"HTTP/1.1 400 Bad Request\r\n\r\nLines must end with CRLF")
+                .unwrap();
+            return;
+        }
+
+        if line.trim().is_empty() {
+            break;
+        }
+
+        let field_line = line.split_once(":").expect("Shits fucked: {}");
+        field_lines.insert(field_line.0.to_owned(), field_line.1.trim().to_owned());
+
+        is_first_line = false;
+    }
+
+    dbg!(&field_lines);
+
+    stream
+        .write_all(b"HTTP/1.1 200 OK\r\n\r\nHello, World!")
+        .unwrap();
+}
+
 fn main() {
     let listener = TcpListener::bind("127.0.0.1:8080").unwrap();
 
     for stream in listener.incoming() {
-        let mut stream = stream.unwrap();
-        let mut reader = BufReader::new(&mut stream);
-
-        loop {
-            let mut line = String::new();
-            reader.read_line(&mut line).unwrap();
-            print!("{line}");
-
-            if line.trim().is_empty() {
-                break;
-            }
-        }
-
-        stream
-            .write_all(b"HTTP/1.1 200 OK\r\n\r\nHello, World!")
-            .unwrap();
+        let stream = stream.unwrap();
+        handle_request(stream)
     }
 }