package handlers

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

	"github.com/jackc/pgx/v5/pgxpool"

	"shop/internal/check"
)

type HealthHandler struct {
	pool *pgxpool.Pool
}

func NewHealthHandler(pool *pgxpool.Pool) *HealthHandler {
	return &HealthHandler{pool: pool}
}

func (h *HealthHandler) Health(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	report, err := check.WithDatabase(ctx, h.pool)
	if err != nil {
		writeJSON(w, http.StatusServiceUnavailable, map[string]any{
			"status":  "error",
			"error":   err.Error(),
			"version": report.AppVersion,
		})
		return
	}

	status := "ok"
	code := http.StatusOK
	if !report.Healthy() {
		status = "degraded"
		code = http.StatusServiceUnavailable
	}

	writeJSON(w, code, map[string]any{
		"status":      status,
		"app_version": report.AppVersion,
		"go_version":  report.GoVersion,
		"checks":      report.Items,
	})
}

func (h *HealthHandler) Version(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	report, _ := check.WithDatabase(ctx, h.pool)
	writeJSON(w, http.StatusOK, report)
}

func writeJSON(w http.ResponseWriter, code int, v any) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	w.WriteHeader(code)
	_ = json.NewEncoder(w).Encode(v)
}