package site

import (
	"fmt"
	"log/slog"
	"net/http"
	"path"
	"sync"
)

type counter struct {
	hits map[string]int
	mu   sync.Mutex
}

type handler struct {
	logger          *slog.Logger
	requestsCounter *counter
}

func newHandler(logger *slog.Logger) *handler {
	return &handler{
		logger:          logger,
		requestsCounter: &counter{hits: make(map[string]int)},
	}
}

func (h *handler) LoggingMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		h.logger.Debug("Received request", "path", r.URL.Path)
		next.ServeHTTP(w, r)
		h.logger.Debug("Finished Request", "path", r.URL.Path)
	})
}

func (h *handler) RequestsCounterMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		h.requestsCounter.mu.Lock()
		h.requestsCounter.hits[r.URL.Path] += 1
		h.requestsCounter.mu.Unlock()
		next.ServeHTTP(w, r)
	})
}

func (h *handler) Ping(w http.ResponseWriter, r *http.Request) {
	fmt.Fprintf(w, "Pong")
}

func (h *handler) Index(w http.ResponseWriter, r *http.Request) {
	h.logger.Info(r.URL.Path)

	if template, isOk := templates[path.Base(r.URL.Path)]; isOk {
		h.logger.Info("Found template")
		template.ExecuteTemplate(w, "base", nil)
	} else {
		h.logger.Info("default template")
		templates["index"].ExecuteTemplate(w, "base", nil)
	}
}

func (h *handler) FileServer(w http.ResponseWriter, r *http.Request) {
	h.logger.Info("handled by file server router")
	http.FileServer(http.FS(staticContent)).ServeHTTP(w, r)
}

func (h *handler) Metrics(w http.ResponseWriter, r *http.Request) {
	h.requestsCounter.mu.Lock()
	defer h.requestsCounter.mu.Unlock()
	for path, hits := range h.requestsCounter.hits {
		fmt.Fprintf(w, "http_requests_total{handler=\"%s\"} %d\n", path, hits)
	}
}
func (h *handler) Healthz(w http.ResponseWriter, r *http.Request) {
	fmt.Fprintln(w, "Ok")
}

func (h *handler) NotFound(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "Page Not Found", http.StatusNotFound)
}