1 files changed, 105 insertions, 0 deletions
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..11d7370
--- /dev/null
+++ b/main.go
@@ -0,0 +1,105 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"math/rand/v2"
+	"net/http"
+	"unicode/utf8"
+)
+
+const charSet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
+const version = "0.0.1"
+
+var Table map[string]string = make(map[string]string)
+
+type Request struct {
+	URL string
+}
+
+type Response struct {
+	Version  string
+	Status   string
+	Original string
+	New      string
+}
+
+func NewRequest(r *http.Request) (Request, error) {
+	var request Request
+
+	err := json.NewDecoder(r.Body).Decode(&request)
+
+	return request, err
+}
+
+func log_header(r *http.Request) {
+	log.Println("Header {")
+	for k, v := range r.Header {
+		log.Printf("\t\"%s\": \"%s\"\n", k, v)
+	}
+	log.Println("}")
+}
+
+func redirect(w http.ResponseWriter, r *http.Request) {
+	log.Println("Request for:", r.URL.String())
+	log_header(r)
+
+	_, i := utf8.DecodeRuneInString(r.URL.String())
+	url := r.URL.String()[i:]
+
+	original, ok := Table[url]
+
+	if ok {
+		w.Header().Set("location", original)
+		http.Error(w, http.StatusText(301), 301)
+	} else {
+		http.Error(w, http.StatusText(404), 404)
+	}
+}
+
+func shorten(w http.ResponseWriter, r *http.Request) {
+	log.Println("Request to Shorten")
+	log_header(r)
+
+	request, err := NewRequest(r)
+	if err != nil {
+		http.Error(w, http.StatusText(500), 500)
+	}
+
+	url := GenerateString(4)
+	_, ok := Table[url]
+
+	for ok {
+		url = GenerateString(4)
+		_, ok = Table[url]
+	}
+
+	Table[url] = request.URL
+
+	response := Response{version, "ok", request.URL, url}
+
+	data, err := json.Marshal(response)
+	if err != nil {
+		http.Error(w, http.StatusText(500), 500)
+	}
+
+	fmt.Fprintf(w, "%s", string(data))
+}
+
+func GenerateString(size uint) string {
+	buffer := make([]rune, size)
+
+	for i := uint(0); i < size; i++ {
+		index := rand.Uint() % uint(len(charSet))
+		buffer[i] = []rune(charSet)[index]
+	}
+
+	return string(buffer)
+}
+
+func main() {
+	http.HandleFunc("/shorten", shorten)
+	http.HandleFunc("/", redirect)
+	log.Fatal(http.ListenAndServe(":8000", nil))
+}