package handler

import (
	"database/sql"
	"krafttrainer/internal/model"
	"net/http"
	"strings"
)

// handleListSets behandelt GET /api/v1/sets.
func (h *Handler) handleListSets(w http.ResponseWriter, r *http.Request) {
	uid, err := userID(r)
	if err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}

	sets, err := h.store.ListSets(uid)
	if err != nil {
		writeError(w, http.StatusInternalServerError, "Fehler beim Laden der Sets")
		return
	}
	writeJSON(w, http.StatusOK, sets)
}

// handleCreateSet behandelt POST /api/v1/sets.
func (h *Handler) handleCreateSet(w http.ResponseWriter, r *http.Request) {
	uid, err := userID(r)
	if err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}

	var req model.CreateSetRequest
	if err := decodeJSON(r, &req); err != nil {
		writeError(w, http.StatusBadRequest, "Ungültiger Request-Body")
		return
	}
	if err := req.Validate(); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}

	set, err := h.store.CreateSet(uid, &req)
	if err != nil {
		if strings.Contains(err.Error(), "existiert nicht") {
			writeError(w, http.StatusBadRequest, err.Error())
			return
		}
		writeError(w, http.StatusInternalServerError, "Fehler beim Erstellen des Sets")
		return
	}
	writeJSON(w, http.StatusCreated, set)
}

// handleUpdateSet behandelt PUT /api/v1/sets/{id}.
// Ersetzt Name und Übungszuordnungen vollständig.
func (h *Handler) handleUpdateSet(w http.ResponseWriter, r *http.Request) {
	uid, err := userID(r)
	if err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	id, err := pathID(r, "id")
	if err != nil {
		writeError(w, http.StatusBadRequest, "Ungültige ID")
		return
	}

	var req model.UpdateSetRequest
	if err := decodeJSON(r, &req); err != nil {
		writeError(w, http.StatusBadRequest, "Ungültiger Request-Body")
		return
	}
	if err := req.Validate(); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}

	set, err := h.store.UpdateSet(id, uid, &req)
	if err != nil {
		if strings.Contains(err.Error(), "existiert nicht") {
			writeError(w, http.StatusBadRequest, err.Error())
			return
		}
		writeError(w, http.StatusInternalServerError, "Fehler beim Aktualisieren des Sets")
		return
	}
	if set == nil {
		writeError(w, http.StatusNotFound, "Set nicht gefunden")
		return
	}
	writeJSON(w, http.StatusOK, set)
}

// handleDeleteSet behandelt DELETE /api/v1/sets/{id}.
// Führt einen Soft-Delete durch (setzt deleted_at).
func (h *Handler) handleDeleteSet(w http.ResponseWriter, r *http.Request) {
	uid, err := userID(r)
	if err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	id, err := pathID(r, "id")
	if err != nil {
		writeError(w, http.StatusBadRequest, "Ungültige ID")
		return
	}

	err = h.store.SoftDeleteSet(id, uid)
	if err == sql.ErrNoRows {
		writeError(w, http.StatusNotFound, "Set nicht gefunden")
		return
	}
	if err != nil {
		writeError(w, http.StatusInternalServerError, "Fehler beim Löschen des Sets")
		return
	}
	w.WriteHeader(http.StatusNoContent)
}