package api

import (
	"errors"
	"net/http"
	"time"

	"github.com/go-chi/chi/v5"

	"github.com/iliaivanov/spec-kit-remote/cmd/dev-pod-api/internal/model"
	"github.com/iliaivanov/spec-kit-remote/cmd/dev-pod-api/internal/store"
)

func (s *Server) handleGetUserUsage(w http.ResponseWriter, r *http.Request) {
	targetUser := chi.URLParam(r, "user")

	if !canAccess(r, targetUser) {
		writeError(w, http.StatusForbidden, "access denied")
		return
	}

	user, err := s.Users.GetUser(r.Context(), targetUser)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			writeError(w, http.StatusNotFound, "user not found")
			return
		}
		writeError(w, http.StatusInternalServerError, "failed to get user")
		return
	}

	now := time.Now()
	usage, err := s.Usage.GetUsage(r.Context(), targetUser, now.Year(), now.Month(), user.Quota.MonthlyPodHours)
	if err != nil {
		writeError(w, http.StatusInternalServerError, "failed to get usage")
		return
	}

	writeJSON(w, http.StatusOK, map[string]*model.UsageSummary{
		"current_month": usage,
	})
}

func (s *Server) handleBillingSummary(w http.ResponseWriter, r *http.Request) {
	if RoleFromContext(r.Context()) != model.RoleAdmin {
		writeError(w, http.StatusForbidden, "admin access required")
		return
	}

	users, err := s.Users.ListUsers(r.Context())
	if err != nil {
		writeError(w, http.StatusInternalServerError, "failed to list users")
		return
	}

	now := time.Now()
	summaries := make([]model.UserUsageSummary, 0, len(users))
	for _, u := range users {
		usage, err := s.Usage.GetUsage(r.Context(), u.ID, now.Year(), now.Month(), u.Quota.MonthlyPodHours)
		if err != nil {
			s.Logger.Error("failed to get usage for user", "user", u.ID, "error", err)
			continue
		}
		summaries = append(summaries, model.UserUsageSummary{
			UserID: u.ID,
			Usage:  *usage,
		})
	}
	writeJSON(w, http.StatusOK, summaries)
}

func (s *Server) handleBillingHistory(w http.ResponseWriter, r *http.Request) {
	targetUser := chi.URLParam(r, "user")

	if !canAccess(r, targetUser) {
		writeError(w, http.StatusForbidden, "access denied")
		return
	}

	if _, err := s.Users.GetUser(r.Context(), targetUser); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			writeError(w, http.StatusNotFound, "user not found")
			return
		}
		writeError(w, http.StatusInternalServerError, "failed to get user")
		return
	}

	now := time.Now()
	daily, err := s.Usage.GetDailyUsage(r.Context(), targetUser, now.Year(), now.Month())
	if err != nil {
		writeError(w, http.StatusInternalServerError, "failed to get usage history")
		return
	}
	if daily == nil {
		daily = []model.DailyUsage{}
	}
	writeJSON(w, http.StatusOK, daily)
}