package main

import (
	"flag"
	"log"
	"net/http"
	"strings"

	"github.com/tgckpg/resolver-go/internal/closure"
	"github.com/tgckpg/resolver-go/internal/generated"
	"github.com/tgckpg/resolver-go/internal/resolver"
)

func main() {
	addr := flag.String("addr", ":8080", "listen address")
	src := flag.String("src", "./src", "BotanJS source root")
	flag.Parse()

	r, err := resolver.New(*src, generated.ClassMap)
	if err != nil {
		log.Fatal(err)
	}

	h := handler{
		r:       r,
		closure: closure.NewCompileCache(2),
	}
	http.HandleFunc("/", h.index)
	log.Printf("botan-api listening on %s", *addr)
	log.Fatal(http.ListenAndServe(*addr, nil))
}

type handler struct {
	r       *resolver.Resolver
	closure *closure.CompileCache
}

func (h handler) index(w http.ResponseWriter, req *http.Request) {
	path := strings.Trim(req.URL.Path, "/")
	if path == "" {
		_, _ = w.Write([]byte("BotanJS Go resolver API\n"))
		return
	}
	parts := strings.SplitN(path, "/", 2)
	modeText := parts[0]
	code := ""
	if len(parts) == 2 {
		code = parts[1]
	} else {
		code = req.URL.Query().Get("p")
	}
	if code == "" {
		http.Error(w, "missing request payload", http.StatusBadRequest)
		return
	}

	outMode := resolver.ModeJS
	if strings.HasSuffix(modeText, "css") {
		outMode = resolver.ModeCSS
	} else if !strings.HasSuffix(modeText, "js") {
		http.Error(w, "invalid mode", http.StatusBadRequest)
		return
	}

	res, err := h.r.ResolveRequest(code, outMode, nil)
	if err != nil {
		http.Error(w, err.Error(), http.StatusNotFound)
		return
	}

	if outMode == resolver.ModeJS {
		if compiled, ok := h.closure.Get(res.Hash); ok {
			w.Header().Set("Content-Type", "application/javascript")
			w.Header().Set("X-Botan-Compiled", "hit")
			w.Write(compiled)
			return
		}

		jsExterns, err := h.r.GetExterns(generated.Externs)
		if err != nil {
			http.Error(w, err.Error(), http.StatusNotFound)
			return
		}

		h.closure.Enqueue(closure.CompileJob{
			Hash:          res.Hash,
			Mode:          "js",
			ExternSources: jsExterns,
			JSSources: []closure.SourceInput{
				{
					Name:   "botanjs-" + res.Hash + ".js",
					Source: string(res.Content),
				},
			},
			Defines: map[string]any{
				"DEBUG": false,
			},
		})
	}

	// Compatibility flags:
	//   rjs/rcss/ojs/ocss => content
	//   hjs/hcss          => hash filename only
	//   js/css            => currently content; cluster compiler can switch this later.
	if strings.HasPrefix(modeText, "h") {
		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
		_, _ = w.Write([]byte(res.Hash))
		return
	}
	w.Header().Set("Content-Type", res.ContentType)
	w.Header().Set("X-Botan-Compiled", "miss")

	_, _ = w.Write(res.Content)
}