import { useMutation, useQueryClient } from "@tanstack/react-query";
import { supabase } from "@/auth/supabase";

/**
 * Hook genérico para actualizar una tabla y guardar respaldo en historico_cambios
 * 
 * @param tableName Nombre de la tabla a actualizar
 * @param idKey Campo que se usa para hacer eq (por defecto 'id')
 */
export function useSupabaseUpdateWithHistory<T extends Record<string, any>>(
  tableName: string,
  idKey: keyof T = "id" as keyof T
) {
  const qc = useQueryClient();

  // Generar diferencias tipo JSON Patch
  function generateDiff(oldData: T, newData: Partial<T>) {
    const changes: any[] = [];
    for (const key of Object.keys(newData)) {
      const oldValue = (oldData as any)[key];
      const newValue = (newData as any)[key];
      if (newValue !== undefined && newValue !== oldValue) {
        changes.push({
          op: "replace",
          path: `/${key}`,
          from: oldValue,
          value: newValue,
        });
      }
    }
    return changes;
  }

  const mutation = useMutation({
    mutationFn: async ({
      oldData,
      newData,
    }: {
      oldData: T;
      newData: Partial<T>;
    }) => {
      const diff = generateDiff(oldData, newData);

      if (diff.length > 0) {
        const { error: backupError } = await supabase
          .from("historico_cambios")
          .insert({
            id_plan_estudios: oldData.id ?? null, // ajusta si es otra tabla
            tabla_afectada: tableName,
            json_cambios: diff,
            created_at: new Date().toISOString(),
          });

        if (backupError) throw backupError;
      }

      const { error } = await supabase
        .from(tableName)
        .update(newData)
        .eq(idKey as string, oldData[idKey]);

      if (error) throw error;
    },
  });

  return { mutation };
}