refactor: introduce lex-serve package

1 files changed, 144 insertions, 0 deletions

diff --git a/lex-serve/main.go b/lex-serve/main.go
new file mode 100644
index 0000000..d0fb690
--- /dev/null
+++ b/lex-serve/main.go
@@ -0,0 +1,144 @@
+package main
+
+import (
+	"embed"
+	"encoding/json"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+	"text/template"
+)
+
+//go:embed countries.json
+var countriesJSON []byte
+
+func main() {
+	domain := os.Getenv("DOMAIN")
+	if domain == "" {
+		log.Fatal("DOMAIN environment variable must be set")
+	}
+
+	var handler = handler{domain: domain, lawsByCC: map[string]map[string]law{}}
+	err := json.Unmarshal(countriesJSON, &handler.countries)
+	if err != nil {
+		log.Fatal("countries.json ", err)
+	}
+
+	lawFiles, err := ioutil.ReadDir("laws")
+	if err != nil {
+		log.Fatal(err)
+	}
+	for _, file := range lawFiles {
+		text, err := ioutil.ReadFile("laws/" + file.Name())
+		if err != nil {
+			log.Fatal(file.Name(), err)
+		}
+		var laws []law
+		err = json.Unmarshal([]byte(text), &laws)
+		if err != nil {
+			log.Fatal(file.Name(), err)
+		}
+		cc := strings.SplitN(file.Name(), ".", 2)[0]
+		handler.lawsByCC[cc] = map[string]law{}
+		for _, law := range laws {
+			if law.Redir != "" {
+				handler.lawsByCC[cc][law.Redir] = law
+			}
+		}
+	}
+	http.HandleFunc("/", handler.handle)
+	println("listening on 8000")
+	log.Fatal(http.ListenAndServe(":8000", nil))
+}
+
+//go:embed templates
+var templates embed.FS
+
+var tpl, _ = template.New("").Funcs(template.FuncMap{
+	"ToUpper": strings.ToUpper,
+}).ParseFS(templates, "templates/*")
+
+type handler struct {
+	domain    string
+	countries map[string]country
+	lawsByCC  map[string]map[string]law
+}
+
+func (h *handler) handle(w http.ResponseWriter, r *http.Request) {
+	if r.Host == h.domain {
+		if r.URL.Path != "/" {
+			w.WriteHeader(http.StatusNotFound)
+			w.Write([]byte("page not found"))
+			return
+		}
+		err := tpl.ExecuteTemplate(w, "index.html.tmpl", map[string]any{
+			"Countries": h.countries,
+			"Domain":    r.Host,
+		})
+		if err != nil {
+			log.Fatal(err)
+		}
+		return
+	}
+
+	cc, isSubdomain := strings.CutSuffix(r.Host, "."+h.domain)
+	if !isSubdomain {
+		w.Write([]byte("unknown host"))
+		return
+	}
+	key := strings.TrimLeft(r.URL.Path, "/")
+	if len(key) > 0 {
+		val, ok := h.lawsByCC[cc][key]
+		if !ok {
+			w.WriteHeader(http.StatusNotFound)
+			w.Write([]byte("unknown law"))
+			return
+		}
+		http.Redirect(w, r, val.URL, 302)
+	} else {
+		query := r.URL.Query().Get("q")
+		if query != "" {
+			country, ok := h.countries[cc]
+			if !ok {
+				w.WriteHeader(http.StatusNotFound)
+				w.Write([]byte("search not implemented for this country"))
+				return
+			}
+			if country.HasPlaceholder() {
+				http.Redirect(w, r, strings.Replace(country.SearchURL, "%s", url.QueryEscape(query), 1), 302)
+				return
+			} else {
+				w.WriteHeader(http.StatusBadRequest)
+			}
+		}
+		_, hasJSONLaws := h.lawsByCC[cc]
+		err := tpl.ExecuteTemplate(w, "search.html.tmpl", map[string]any{
+			"TLD":         cc,
+			"Domain":      h.domain,
+			"Country":     h.countries[cc],
+			"HasJSONLaws": hasJSONLaws,
+		})
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+}
+
+type law struct {
+	URL   string
+	Title string
+	Abbr  string
+	Redir string
+}
+
+type country struct {
+	Name      string
+	SearchURL string `json:"search_url"`
+}
+
+func (c country) HasPlaceholder() bool {
+	return strings.Contains(c.SearchURL, "%s")
+}