package handler

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

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

	"financeiro-carvalho/internal/model"
	"financeiro-carvalho/internal/repository"
	"financeiro-carvalho/internal/service"
)

type RecurringHandler struct {
	svc *service.RecurringService
}

func NewRecurringHandler(svc *service.RecurringService) *RecurringHandler {
	return &RecurringHandler{svc: svc}
}

func (h *RecurringHandler) List(w http.ResponseWriter, r *http.Request) {
	items, err := h.svc.List(r.Context())
	if err != nil {
		respondError(w, http.StatusInternalServerError, "failed to list recurring expenses")
		return
	}
	respondJSON(w, http.StatusOK, items)
}

func (h *RecurringHandler) Create(w http.ResponseWriter, r *http.Request) {
	var in model.RecurringInput
	if err := json.NewDecoder(r.Body).Decode(&in); err != nil {
		respondError(w, http.StatusBadRequest, "invalid JSON")
		return
	}
	out, err := h.svc.Create(r.Context(), in)
	if err != nil {
		respondError(w, http.StatusBadRequest, err.Error())
		return
	}
	respondJSON(w, http.StatusCreated, out)
}

func (h *RecurringHandler) Update(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(chi.URLParam(r, "id"))
	if err != nil {
		respondError(w, http.StatusBadRequest, "invalid id")
		return
	}
	var in model.RecurringInput
	if err := json.NewDecoder(r.Body).Decode(&in); err != nil {
		respondError(w, http.StatusBadRequest, "invalid JSON")
		return
	}
	out, err := h.svc.Update(r.Context(), id, in)
	if errors.Is(err, repository.ErrNotFound) {
		respondError(w, http.StatusNotFound, "not found")
		return
	}
	if err != nil {
		respondError(w, http.StatusBadRequest, err.Error())
		return
	}
	respondJSON(w, http.StatusOK, out)
}

func (h *RecurringHandler) Delete(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(chi.URLParam(r, "id"))
	if err != nil {
		respondError(w, http.StatusBadRequest, "invalid id")
		return
	}
	if err := h.svc.Delete(r.Context(), id); err != nil {
		respondError(w, http.StatusNotFound, "not found")
		return
	}
	w.WriteHeader(http.StatusNoContent)
}

func (h *RecurringHandler) MonthlyStatus(w http.ResponseWriter, r *http.Request) {
	month := r.URL.Query().Get("month")
	if month == "" {
		respondError(w, http.StatusBadRequest, "month param required (YYYY-MM)")
		return
	}
	statuses, err := h.svc.MonthlyStatus(r.Context(), month)
	if err != nil {
		respondError(w, http.StatusInternalServerError, "failed to compute status")
		return
	}
	respondJSON(w, http.StatusOK, statuses)
}

func (h *RecurringHandler) Ignore(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(chi.URLParam(r, "id"))
	if err != nil {
		respondError(w, http.StatusBadRequest, "invalid id")
		return
	}
	var body struct {
		Month  string `json:"month"`
		Reason string `json:"reason"`
	}
	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
		respondError(w, http.StatusBadRequest, "invalid JSON")
		return
	}
	if err := h.svc.Ignore(r.Context(), id, body.Month, body.Reason); err != nil {
		respondError(w, http.StatusInternalServerError, "failed to ignore")
		return
	}
	w.WriteHeader(http.StatusNoContent)
}

func (h *RecurringHandler) Unignore(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(chi.URLParam(r, "id"))
	if err != nil {
		respondError(w, http.StatusBadRequest, "invalid id")
		return
	}
	month := r.URL.Query().Get("month")
	if err := h.svc.Unignore(r.Context(), id, month); err != nil {
		respondError(w, http.StatusInternalServerError, "failed to unignore")
		return
	}
	w.WriteHeader(http.StatusNoContent)
}