From ed90eb566ec22098b770771c0634af8d5d07740c Mon Sep 17 00:00:00 2001
From: Superkooka <aymeric.gueracague@gmail.com>
Date: Sun, 28 Mar 2021 23:59:46 +0200
Subject: [PATCH] feat: parsing of headers feat: return simple static html
 reponse

---
 src/http/method.cr   | 13 ++++++
 src/http/request.cr  | 99 ++++++++++++++++++++++++++++++++++++++++++++
 src/http/response.cr | 22 ++++++++++
 src/main.cr          | 43 ++++++++++++++++++-
 static/hellow.html   | 13 ++++++
 5 files changed, 189 insertions(+), 1 deletion(-)
 create mode 100644 src/http/method.cr
 create mode 100644 src/http/request.cr
 create mode 100644 src/http/response.cr
 create mode 100644 static/hellow.html

diff --git a/src/http/method.cr b/src/http/method.cr
new file mode 100644
index 0000000..a96a70a
--- /dev/null
+++ b/src/http/method.cr
@@ -0,0 +1,13 @@
+enum Method
+    GET
+    POST
+    PUT
+    PATCH
+    DELETE
+    HEAD
+    OPTIONS
+    CONNECT
+    TRACE
+
+    NON_STANDARD
+end
\ No newline at end of file
diff --git a/src/http/request.cr b/src/http/request.cr
new file mode 100644
index 0000000..4f57d73
--- /dev/null
+++ b/src/http/request.cr
@@ -0,0 +1,99 @@
+require "./method"
+require "uri"
+
+class Request
+
+    @method : Method = Method::NON_STANDARD
+    @protocol_name : String | Nil
+    @protocol_version : String | Nil
+    @headers : Hash(String, String) = Hash(String, String).new()
+    @body : String = ""
+
+    @@status_line_regex = /(?'method'[A-Z]+) (?'uri'[^ ]+) (?'protocol'(?'protocol_name'[^ ]+)\/(?'protocol_version'[0-9]+.[0-9]+))/
+    @@header_line_regex = /^(?'name'[^:]+): (?'values'.+)/
+
+    def initialize(socket)
+        if socket.nil?
+            raise "Oooops"
+        end
+
+        plain_request = socket.receive[0]
+
+        current_header = ""
+        is_body = false
+        is_status_line = true
+
+        plain_request.chars.each do |char|
+            if is_body
+                @body += char
+                next
+            end
+
+            current_header += char
+
+            if current_header == "\r\n"
+                is_body = true
+                next
+            end
+
+            if current_header.ends_with?("\r\n") # End of header
+                if !is_status_line
+                    regexified_header = @@header_line_regex.match(current_header)
+                    if regexified_header.nil?
+                        raise "Header regex is broken :aie:"
+                    end
+
+                    @headers[regexified_header["name"]] = regexified_header["values"].gsub({"\r": "", "\n": ""})
+                else 
+                    is_status_line = false
+                    regexified_status_line = @@status_line_regex.match(current_header)
+                    if regexified_status_line.nil?
+                        raise "Status line regex is broken :aie:"
+                    end
+
+                    method = Method.parse?(regexified_status_line["method"])
+                    if method.nil?
+                        @method = Method::NON_STANDARD
+                    else
+                        @method = method
+                    end
+
+                    protocol_name = regexified_status_line["protocol_name"]
+                    if protocol_name.nil?
+                        raise "Status Line must have a valid protocol name"
+                    else
+                        @protocol_name = protocol_name
+                    end
+
+                    protocol_version = regexified_status_line["protocol_version"]
+                    if protocol_version.nil?
+                        raise "Status Line must have a valid protocol version"
+                    else
+                        @protocol_version = protocol_version
+                    end
+                end
+                current_header = ""
+            end
+        end
+
+        if @protocol_name.nil?
+            raise "Request must have a protocol name in status line"
+        end
+
+        if @protocol_version.nil?
+            raise "Request must have a protocol version in status line"
+        end
+
+        puts "Method: " + @method.to_s
+        puts "Protocol name: " + @protocol_name.to_s
+        puts "Protocol version: " + @protocol_version.to_s
+        puts "Headers: " + @headers.to_s
+        puts "Body: "
+        puts @body
+        puts "\r\n"
+    end
+
+    def method : Method
+        return @method
+    end
+end
diff --git a/src/http/response.cr b/src/http/response.cr
new file mode 100644
index 0000000..b66f143
--- /dev/null
+++ b/src/http/response.cr
@@ -0,0 +1,22 @@
+class Response
+    def initialize()
+        @headers = [
+            "HTTP/1.1 200 OK"
+        ]
+    end
+
+    def to_s()
+        body = File.read("/vagrant/static/hellow.html")
+        @headers << "Content-Length: " + (body.bytesize + 1).to_s() # +1 for CRLF ?
+        
+        request = ""
+        @headers.each() do |header|
+            request += header + "\r\n"
+        end
+        request += "\r\n"
+
+        request += body
+
+        return request
+    end
+end
diff --git a/src/main.cr b/src/main.cr
index 8a035e9..f6cc909 100644
--- a/src/main.cr
+++ b/src/main.cr
@@ -1 +1,42 @@
-puts "Hellow World !"
+require "socket"
+require "option_parser"
+
+require "./http/request"
+require "./http/response"
+
+def handle_request(client)
+  request = Request.new(client)
+  response = Response.new()
+
+  client.puts response.to_s()
+  
+  client.close
+end
+
+tcp_port = 8000
+hostname = "127.0.0.1"
+
+OptionParser.parse do |parser|
+  parser.banner = "Usage: webcrystal [arguments]"
+  parser.on("-p PORT", "--port=PORT", "Specify the port to listen, default to 8000") do |port|
+    tcp_port = port.to_u32
+  end
+  parser.on("-n NAME", "--name NAME", "Hostname to listen, default to 127.0.0.1") do |name|
+    hostname = name
+  end
+  parser.on("-h", "--help", "Show this help") do
+    puts parser
+    exit
+  end
+  parser.invalid_option do |flag|
+    STDERR.puts "ERROR: #{flag} is not a valid option."
+    STDERR.puts parser
+    exit(1)
+  end
+end
+
+server = TCPServer.new(hostname, tcp_port)
+
+while client = server.accept?
+  spawn handle_request(client)
+end
diff --git a/static/hellow.html b/static/hellow.html
new file mode 100644
index 0000000..435fda5
--- /dev/null
+++ b/static/hellow.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Wesh</title>
+</head>
+<body>
+    <h1>Hellow World !</h1>
+    <p>Cimer Nuker pour la découverte 😉</p>
+</body>
+</html>
\ No newline at end of file