package api

import (
	"io/fs"
	"net/http"
	"path"

	"github.com/go-chi/chi/v5"
	"github.com/go-chi/chi/v5/middleware"
	"github.com/lerko/nib/internal/db"
)

func NewRouter(store *db.Store, devMode bool, webFS ...fs.FS) chi.Router {
	r := chi.NewRouter()

	r.Use(middleware.Logger)
	r.Use(middleware.Recoverer)

	if devMode {
		r.Use(corsMiddleware)
	}

	r.Route("/api", func(r chi.Router) {
		r.Use(jsonContentType)

		r.Get("/entities", listEntities(store))
		r.Post("/entities", createEntity(store))
		r.Get("/entities/{id}", getEntity(store))
		r.Put("/entities/{id}", updateEntity(store))
		r.Delete("/entities/{id}", deleteEntity(store))
		r.Post("/entities/{id}/promote", promoteEntity(store))
		r.Post("/entities/{id}/demote", demoteEntity(store))
		r.Post("/entities/{id}/use", useEntity(store))
		r.Get("/tags", listTags(store))
	})

	if len(webFS) > 0 && webFS[0] != nil {
		r.Get("/*", spaHandler(webFS[0]))
	}

	return r
}

func spaHandler(fsys fs.FS) http.HandlerFunc {
	fileServer := http.FileServer(http.FS(fsys))
	indexHTML, _ := fs.ReadFile(fsys, "index.html")

	return func(w http.ResponseWriter, r *http.Request) {
		p := r.URL.Path
		if p == "/" || path.Ext(p) == "" {
			w.Header().Set("Content-Type", "text/html; charset=utf-8")
			w.Write(indexHTML)
			return
		}
		fileServer.ServeHTTP(w, r)
	}
}

func jsonContentType(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		next.ServeHTTP(w, r)
	})
}

func corsMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Access-Control-Allow-Origin", "*")
		w.Header().Set("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS")
		w.Header().Set("Access-Control-Allow-Headers", "Content-Type")

		if r.Method == http.MethodOptions {
			w.WriteHeader(http.StatusNoContent)
			return
		}

		next.ServeHTTP(w, r)
	})
}