package handler

import (
	"errors"
	"net/http"

	"github.com/go-chi/chi/v5"
	"github.com/wotra/wotra/internal/service"
)

// WeekHandler serves /api/weeks routes.
type WeekHandler struct {
	svc *service.WeekService
}

func NewWeekHandler(svc *service.WeekService) *WeekHandler {
	return &WeekHandler{svc: svc}
}

func (h *WeekHandler) Routes(r chi.Router) {
	r.Get("/weeks", h.List)
	r.Post("/weeks/{week_key}/close", h.Close)
	r.Delete("/weeks/{week_key}/close", h.Reopen)
}

// List GET /api/weeks?from=YYYY-Www&to=YYYY-Www
func (h *WeekHandler) List(w http.ResponseWriter, r *http.Request) {
	from := r.URL.Query().Get("from")
	to := r.URL.Query().Get("to")
	if from == "" {
		from = "0000-W01"
	}
	if to == "" {
		to = "9999-W53"
	}
	weeks, err := h.svc.ListWeeks(r.Context(), from, to)
	if err != nil {
		writeError(w, http.StatusInternalServerError, err.Error())
		return
	}
	if weeks == nil {
		writeJSON(w, http.StatusOK, []struct{}{})
		return
	}
	writeJSON(w, http.StatusOK, weeks)
}

// Close POST /api/weeks/{week_key}/close
func (h *WeekHandler) Close(w http.ResponseWriter, r *http.Request) {
	weekKey := chi.URLParam(r, "week_key")
	cw, err := h.svc.CloseWeek(r.Context(), weekKey)
	if err != nil {
		switch {
		case errors.Is(err, service.ErrWeekAlreadyClosed):
			writeError(w, http.StatusConflict, err.Error())
		case errors.Is(err, service.ErrWeekHasUnclosedDays):
			writeError(w, http.StatusUnprocessableEntity, err.Error())
		case errors.Is(err, service.ErrNoSettings):
			writeError(w, http.StatusUnprocessableEntity, err.Error())
		default:
			writeError(w, http.StatusInternalServerError, err.Error())
		}
		return
	}
	writeJSON(w, http.StatusOK, cw)
}

// Reopen DELETE /api/weeks/{week_key}/close
func (h *WeekHandler) Reopen(w http.ResponseWriter, r *http.Request) {
	weekKey := chi.URLParam(r, "week_key")
	if err := h.svc.ReopenWeek(r.Context(), weekKey); err != nil {
		switch {
		case errors.Is(err, service.ErrWeekNotClosed):
			writeError(w, http.StatusNotFound, err.Error())
		default:
			writeError(w, http.StatusInternalServerError, err.Error())
		}
		return
	}
	w.WriteHeader(http.StatusNoContent)
}