package eu.eudat.file.transformer.utils.descriptionTemplate;

import eu.eudat.file.transformer.models.descriptiontemplate.DescriptionTemplateFileTransformerModel;
import eu.eudat.file.transformer.models.descriptiontemplate.definition.FieldFileTransformerModel;
import eu.eudat.file.transformer.models.descriptiontemplate.definition.FieldSetFileTransformerModel;
import eu.eudat.file.transformer.models.descriptiontemplate.definition.PageFileTransformerModel;
import eu.eudat.file.transformer.models.descriptiontemplate.definition.SectionFileTransformerModel;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;

public class TemplateFieldSearcher {

    public static List<FieldFileTransformerModel> searchFields(DescriptionTemplateFileTransformerModel template, String key, String value) {
        List<FieldFileTransformerModel> result;
        List<PageFileTransformerModel> pages = template.getDefinition().getPages();
        result = pages.stream().flatMap(pageFileTransformerModel -> searchFieldsFromSections(pageFileTransformerModel.getSections(), key, value).stream()).toList();
        return  result;
    }

    private static List<FieldFileTransformerModel> searchFieldsFromSections(List<SectionFileTransformerModel> sections, String key, String value) {
        List<FieldFileTransformerModel> result = new ArrayList<>();
        for (SectionFileTransformerModel section : sections) {
            if (section.getSections() != null && !section.getSections().isEmpty()) {
                result.addAll(searchFieldsFromSections(section.getSections(), key, value));
            }
            if (section.getFieldSets() != null && !section.getFieldSets().isEmpty()) {
                List<FieldSetFileTransformerModel> fieldSets = section.getFieldSets();
                for (FieldSetFileTransformerModel fieldSet : fieldSets) {
                    List<FieldFileTransformerModel> fields = fieldSet.getFields();
                    for (FieldFileTransformerModel field : fields) {
                        Method keyGetter = Arrays.stream(FieldFileTransformerModel.class.getDeclaredMethods()).filter(method -> method.getName().equals(makeGetter(key))).findFirst().orElse(null);
                        if (keyGetter != null && keyGetter.canAccess(field)) {
                            try {
                                if (keyGetter.invoke(field).equals(value) || keyGetter.invoke(field).toString().startsWith(value)) {
                                    result.add(field);
                                } else if(keyGetter.getReturnType().isAssignableFrom(List.class)) {
                                    List nodes = (List) keyGetter.invoke(field);
                                    for (Object item : nodes) {
                                        if (item.toString().equals(value) || item.toString().startsWith(value)) {
                                            result.add(field);
                                        }
                                    }
                                }
                            } catch (IllegalAccessException | InvocationTargetException e) {
                                throw new RuntimeException(e);
                            }
                        }
                    }
                }
            }
        }
        return result;
    }

    private static String makeGetter(String fieldName) {
        return "get" + fieldName.substring(0, 1).toUpperCase(Locale.ROOT) + fieldName.substring(1);
    }
}