package httpapp

import (
	"encoding/json"
	"log"
	"net/http"
)

func (a *App) handleDashboard(w http.ResponseWriter, r *http.Request) {
	data := map[string]any{
		"Title": "Dashboard",
		"Build": map[string]string{
			"version": "v0.1.0-dev",
		},
	}
	a.render(w, "dashboard.html", data)
}

func (a *App) handleHealthz(w http.ResponseWriter, r *http.Request) {
	id, _ := r.Context().Value(requestIDKey).(string)
	resp := map[string]any{
		"status": "ok",
		"ts":     id, // request ID for correlation
	}
	writeJSON(w, http.StatusOK, resp)
}

func (a *App) handleMetrics(w http.ResponseWriter, r *http.Request) {
	// Stub metrics (Prometheus format). We'll wire real collectors later.
	w.Header().Set("Content-Type", "text/plain; version=0.0.4")
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte(
		`# HELP pluto_build_info Build info
# TYPE pluto_build_info gauge
pluto_build_info{version="v0.1.0-dev"} 1
# HELP pluto_up Whether the pluto-api process is up
# TYPE pluto_up gauge
pluto_up 1
`,
	))
}

func (a *App) render(w http.ResponseWriter, name string, data any) {
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	// base.html defines layout; dashboard.html will invoke it via template inheritance style.
	if err := a.tmpl.ExecuteTemplate(w, name, data); err != nil {
		log.Printf("template render error: %v", err)
		http.Error(w, "template render error", http.StatusInternalServerError)
		return
	}
}

func writeJSON(w http.ResponseWriter, code int, v any) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	w.WriteHeader(code)
	if err := json.NewEncoder(w).Encode(v); err != nil {
		log.Printf("json encode error: %v", err)
	}
}
