package handler

import (
	"errors"
	"net/http"

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

// DayHandler serves /api/days routes.
type DayHandler struct {
	svc *service.DayService
}

func NewDayHandler(svc *service.DayService) *DayHandler {
	return &DayHandler{svc: svc}
}

func (h *DayHandler) Routes(r chi.Router) {
	r.Get("/days", h.List)
	r.Post("/days/{day_key}/close", h.Close)
	r.Post("/days/{day_key}/mark", h.Mark)
	r.Delete("/days/{day_key}/close", h.Reopen)
}

// List GET /api/days?from=YYYY-MM-DD&to=YYYY-MM-DD
func (h *DayHandler) List(w http.ResponseWriter, r *http.Request) {
	from := r.URL.Query().Get("from")
	to := r.URL.Query().Get("to")
	if from == "" {
		from = "0000-01-01"
	}
	if to == "" {
		to = "9999-12-31"
	}
	days, err := h.svc.ListDays(r.Context(), from, to)
	if err != nil {
		writeError(w, http.StatusInternalServerError, err.Error())
		return
	}
	if days == nil {
		writeJSON(w, http.StatusOK, []struct{}{})
		return
	}
	writeJSON(w, http.StatusOK, days)
}

// Close POST /api/days/{day_key}/close
func (h *DayHandler) Close(w http.ResponseWriter, r *http.Request) {
	dayKey := chi.URLParam(r, "day_key")
	cd, err := h.svc.CloseDay(r.Context(), dayKey)
	if err != nil {
		switch {
		case errors.Is(err, service.ErrDayAlreadyClosed):
			writeError(w, http.StatusConflict, err.Error())
		case errors.Is(err, service.ErrRunningEntryOnDay):
			writeError(w, http.StatusConflict, err.Error())
		case errors.Is(err, service.ErrDayHasNoEntries):
			writeError(w, http.StatusUnprocessableEntity, err.Error())
		default:
			writeError(w, http.StatusInternalServerError, err.Error())
		}
		return
	}
	writeJSON(w, http.StatusOK, cd)
}

// Mark POST /api/days/{day_key}/mark
func (h *DayHandler) Mark(w http.ResponseWriter, r *http.Request) {
	dayKey := chi.URLParam(r, "day_key")
	var body struct {
		Kind domain.DayKind `json:"kind"`
	}
	if err := decodeJSON(r, &body); err != nil {
		writeError(w, http.StatusBadRequest, "invalid JSON")
		return
	}
	cd, err := h.svc.MarkDay(r.Context(), dayKey, body.Kind)
	if err != nil {
		writeError(w, http.StatusUnprocessableEntity, err.Error())
		return
	}
	writeJSON(w, http.StatusOK, cd)
}

// Reopen DELETE /api/days/{day_key}/close
func (h *DayHandler) Reopen(w http.ResponseWriter, r *http.Request) {
	dayKey := chi.URLParam(r, "day_key")
	if err := h.svc.ReopenDay(r.Context(), dayKey); err != nil {
		switch {
		case errors.Is(err, service.ErrDayNotClosed):
			writeError(w, http.StatusNotFound, err.Error())
		default:
			writeError(w, http.StatusInternalServerError, err.Error())
		}
		return
	}
	w.WriteHeader(http.StatusNoContent)
}