package main

import (
	"embed"
	"flag"
	"fmt"
	"html/template"
	"io/fs"
	"log"
	"net/http"
)

//go:embed source
var sourceFS embed.FS

func main() {
	port := flag.Int("port", 8081, "port to listen on")
	flag.Parse()

	sourceRoot, err := fs.Sub(sourceFS, "source")
	if err != nil {
		log.Fatal(err)
	}

	mux := http.NewServeMux()
	mux.HandleFunc("GET /{$}", servePage("home", "templates/pages/index.html", sourceRoot, false))
	mux.HandleFunc("GET /research", servePage("research", "templates/pages/research.html", sourceRoot, true))
	mux.HandleFunc("GET /bookkeeping", servePage("bookkeeping", "templates/pages/bookkeeping.html", sourceRoot, true))
	mux.HandleFunc("GET /personal", servePage("personal", "templates/pages/interests.html", sourceRoot, true))

	staticRoot, err := fs.Sub(sourceFS, "source/static")
	if err != nil {
		log.Fatal(err)
	}

	mux.Handle("/static/", http.StripPrefix("/static/", http.FileServerFS(staticRoot)))

	mux.HandleFunc("/favicon.ico", func(w http.ResponseWriter, r *http.Request) {
		http.ServeFileFS(w, r, sourceRoot, "favicon.ico")
	})

	addr := fmt.Sprintf(":%d", *port)
	log.Printf("running on http://localhost%s/\n", addr)
	log.Fatal(http.ListenAndServe(addr, mux))

}

func servePage(name string, templatefile string, sourcefile fs.FS, sub bool) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		tmpl, err := template.ParseFS(sourcefile, "templates/main.html", templatefile)
		if err != nil {
			log.Println("parse error:", err)
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}

		data := struct {
			Title string
			Sub   bool
		}{
			Title: name,
			Sub:   sub,
		}

		w.Header().Set("Content-Type", "text/html; charset=utf-8")
		// execute the base file by name — main.html is the entrypoint
		if err := tmpl.ExecuteTemplate(w, "main.html", data); err != nil {
			log.Println("execute error:", err)
			http.Error(w, err.Error(), http.StatusInternalServerError)
		}
	}
}