package core

import (
	"context"
	"database/sql"
	"errors"
	"log/slog"
	"net/http"
	"spend-sparrow/internal/utils"
	"strings"
)

var (
	ErrNotFound      = errors.New("the value does not exist")
	ErrAlreadyExists = errors.New("row already exists")

	ErrInternal     = errors.New("internal server error")
	ErrUnauthorized = errors.New("you are not authorized to perform this action")

	ErrBadRequest = errors.New("bad request")
)

func TransformAndLogDbError(ctx context.Context, module string, r sql.Result, err error) error {
	if err != nil {
		if errors.Is(err, sql.ErrNoRows) {
			return ErrNotFound
		}
		slog.ErrorContext(ctx, "database sql", "module", module, "err", err)
		return ErrInternal
	}

	if r != nil {
		rows, err := r.RowsAffected()
		if err != nil {
			slog.ErrorContext(ctx, "database rows affected", "module", module, "err", err)
			return ErrInternal
		}

		if rows == 0 {
			slog.InfoContext(ctx, "row not found", "module", module)
			return ErrNotFound
		}
	}

	return nil
}

func HandleError(w http.ResponseWriter, r *http.Request, err error) {
	switch {
	case errors.Is(err, ErrUnauthorized):
		utils.TriggerToastWithStatus(r.Context(), w, r, "error", "You are not autorized to perform this operation.", http.StatusUnauthorized)
		return
	case errors.Is(err, ErrBadRequest):
		utils.TriggerToastWithStatus(r.Context(), w, r, "error", extractErrorMessage(err), http.StatusBadRequest)
		return
	case errors.Is(err, ErrNotFound):
		utils.TriggerToastWithStatus(r.Context(), w, r, "error", extractErrorMessage(err), http.StatusNotFound)
		return
	}

	utils.TriggerToastWithStatus(r.Context(), w, r, "error", "Internal Server Error", http.StatusInternalServerError)
}

func extractErrorMessage(err error) string {
	errMsg := err.Error()
	if errMsg == "" {
		return ""
	}

	return strings.SplitN(errMsg, ":", 2)[0]
}