codecrafters submit [skip ci]

1 files changed, 82 insertions, 0 deletions

diff --git a/app/router.go b/app/router.go
new file mode 100644
index 0000000..4f563d7
--- /dev/null
+++ b/app/router.go
@@ -0,0 +1,82 @@
+package main
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"regexp"
+)
+
+type Router struct {
+	routes []Route
+}
+
+func (r *Router) handler(request *Request) func(*Request) *Response {
+	for _, route := range r.routes {
+		if route.method == request.Method() && route.path.MatchString(request.Target()) {
+			return route.handler
+		}
+	}
+
+	return func(request *Request) *Response {
+		return NewResponse(NotFound, nil, nil)
+	}
+}
+
+func (r *Router) write(writer io.Writer, response *Response) (err error) {
+	_, err = writer.Write(response.StatusLine())
+	if err != nil {
+		return
+	}
+
+	_, err = writer.Write(response.Headers())
+	if err != nil {
+		return
+	}
+
+	_, err = writer.Write(response.Body())
+	if err != nil {
+		return
+	}
+
+	return
+}
+
+func (r *Router) Handle(conn net.Conn) error {
+	request, err := NewRequest(bufio.NewReader(conn))
+	if err != nil {
+		return err
+	}
+
+	return r.write(conn, r.handler(request)(request))
+}
+
+type Route struct {
+	method  string
+	path    *regexp.Regexp
+	handler func(*Request) *Response
+}
+
+type RouterBuilder struct {
+	routes []Route
+}
+
+func (r *RouterBuilder) Add(method string, path *regexp.Regexp, handler func(*Request) *Response) {
+	r.routes = append(r.routes, Route{
+		method:  method,
+		path:    path,
+		handler: handler,
+	})
+}
+
+func (r *RouterBuilder) Build() *Router {
+	return &Router{
+		routes: r.routes,
+	}
+}
+
+func NewRouterBuilder() *RouterBuilder {
+	return &RouterBuilder{
+		routes: make([]Route, 0),
+	}
+}