package main

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

	"github.com/tgckpg/resolver-go/internal/closure"
	"github.com/tgckpg/resolver-go/internal/compilecache"
	"github.com/tgckpg/resolver-go/internal/generated"
	"github.com/tgckpg/resolver-go/internal/minifier/css"
	"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,
		jsCache: compilecache.New(
			closure.NewCompiler(), 2, 128,
		),
		cssCache: compilecache.New(
			css.NewEsbuildCompiler(), 2, 128,
		),
	}
	http.HandleFunc("/", h.index)
	log.Printf("botan-api listening on %s", *addr)
	log.Fatal(http.ListenAndServe(*addr, nil))
}

type handler struct {
	r        *resolver.Resolver
	jsCache  *compilecache.Cache
	cssCache *compilecache.Cache
}

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
	}

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

	if outMode == resolver.ModeJS {
		state, compiled, err := h.jsCache.Get(res.Hash)
		if state == compilecache.Ready {
			w.Header().Set("Content-Type", "application/javascript")
			w.Header().Set("X-Botan-Compiled", "hit")
			elapsed := time.Since(timerStart)
			w.Header().Set("X-Botan-Resolve-Time", elapsed.String())
			w.Write(compiled)
			return
		}

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

		h.jsCache.Enqueue(compilecache.Job{
			Hash: res.Hash,
			Mode: "js",
			Payload: closure.CompilePayload{
				ExternSources: jsExterns,
				JSSources: []closure.SourceInput{
					{
						Name:   "botanjs-" + res.Hash + ".js",
						Source: string(res.Content),
					},
				},
				Defines: map[string]any{
					"DEBUG": false,
				},
			},
		})
	} else if outMode == resolver.ModeCSS {
		state, compiled, _ := h.cssCache.Get(res.Hash)
		if state == compilecache.Ready {
			w.Header().Set("Content-Type", "text/css")
			w.Header().Set("X-Botan-Compiled", "hit")
			elapsed := time.Since(timerStart)
			w.Header().Set("X-Botan-Resolve-Time", elapsed.String())
			w.Write(compiled)
			return
		}

		h.cssCache.Enqueue(compilecache.Job{
			Hash: res.Hash,
			Mode: "css",
			Payload: css.CompilePayload{
				Name:   "style.css",
				Source: string(res.Content),
			},
		})
	}

	w.Header().Set("Content-Type", res.ContentType)
	w.Header().Set("X-Botan-Compiled", "miss")

	elapsed := time.Since(timerStart)
	w.Header().Set("X-Botan-Resolve-Time", elapsed.String())

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