package stats

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

	"rideaware/internal/config"
	"rideaware/internal/middleware"
)

type Handler struct {
	service *Service
}

func NewHandler() *Handler {
	return &Handler{
		service: NewService(),
	}
}

// GetSummary GET /api/protected/stats/summary
func (h *Handler) GetSummary(w http.ResponseWriter, r *http.Request) {
	claims := r.Context().Value(middleware.UserContextKey).(*config.CustomClaims)
	if claims == nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusUnauthorized)
		json.NewEncoder(w).Encode(map[string]string{"error": "unauthorized"})
		return
	}

	summary, err := h.service.GetSummary(claims.UserID)
	if err != nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusInternalServerError)
		json.NewEncoder(w).Encode(map[string]string{"error": "failed to fetch stats"})
		return
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	json.NewEncoder(w).Encode(summary)
}

// GetWeeklyStats GET /api/protected/stats/weekly?weeks=12
func (h *Handler) GetWeeklyStats(w http.ResponseWriter, r *http.Request) {
	claims := r.Context().Value(middleware.UserContextKey).(*config.CustomClaims)
	if claims == nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusUnauthorized)
		json.NewEncoder(w).Encode(map[string]string{"error": "unauthorized"})
		return
	}

	weeks := 12
	if w_str := r.URL.Query().Get("weeks"); w_str != "" {
		if parsed, err := strconv.Atoi(w_str); err == nil {
			weeks = parsed
		}
	}

	stats, err := h.service.GetWeeklyStats(claims.UserID, weeks)
	if err != nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusInternalServerError)
		json.NewEncoder(w).Encode(map[string]string{"error": "failed to fetch weekly stats"})
		return
	}

	if stats == nil {
		stats = []PeriodStats{}
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	json.NewEncoder(w).Encode(stats)
}

// GetMonthlyStats GET /api/protected/stats/monthly?months=12
func (h *Handler) GetMonthlyStats(w http.ResponseWriter, r *http.Request) {
	claims := r.Context().Value(middleware.UserContextKey).(*config.CustomClaims)
	if claims == nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusUnauthorized)
		json.NewEncoder(w).Encode(map[string]string{"error": "unauthorized"})
		return
	}

	months := 12
	if m_str := r.URL.Query().Get("months"); m_str != "" {
		if parsed, err := strconv.Atoi(m_str); err == nil {
			months = parsed
		}
	}

	stats, err := h.service.GetMonthlyStats(claims.UserID, months)
	if err != nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusInternalServerError)
		json.NewEncoder(w).Encode(map[string]string{"error": "failed to fetch monthly stats"})
		return
	}

	if stats == nil {
		stats = []PeriodStats{}
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	json.NewEncoder(w).Encode(stats)
}

// GetPersonalBests GET /api/protected/stats/personal-bests
func (h *Handler) GetPersonalBests(w http.ResponseWriter, r *http.Request) {
	claims := r.Context().Value(middleware.UserContextKey).(*config.CustomClaims)
	if claims == nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusUnauthorized)
		json.NewEncoder(w).Encode(map[string]string{"error": "unauthorized"})
		return
	}

	pbs, err := h.service.GetPersonalBests(claims.UserID)
	if err != nil {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusInternalServerError)
		json.NewEncoder(w).Encode(map[string]string{"error": "failed to fetch personal bests"})
		return
	}

	if pbs == nil {
		pbs = []PersonalBest{}
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	json.NewEncoder(w).Encode(pbs)
}