using System;
using System.Collections.Generic;
using System.Linq;
using InABox.Clients;

namespace InABox.Core
{
    /// <summary>
    /// </summary>
    /// <typeparam name="T">
    ///     Should always be an EntityForm<,></typeparam>
    public class DigitalFormReportDataModel<T> : AutoDataModel<T>
        where T : Entity, IRemotable, IPersistent, new()
    {

        private Guid? FormId { get; set; } = null;

        private CoreTable? FormDataTable { get; set; } = null;

        private DigitalFormVariable[] Variables = null;

        public DigitalFormReportDataModel(Filter<T> filter, Guid? formId = null) : base(filter)
        {
            FormId = formId;
        }

        public override string Name => "Digital Form Reports";

        protected override void CheckRequiredTables(List<string> requiredtables)
        {
            base.CheckRequiredTables(requiredtables);

            requiredtables.Add(TableName<T>());
        }

        private void LoadFormDataTable(Guid formID)
        {
            var formDataTable = new CoreTable();

            formDataTable.Columns.Add(new CoreColumn
            {
                ColumnName = "Parent.ID",
                DataType = typeof(Guid)
            });

            var variables = new Client<DigitalFormVariable>().Load(new Filter<DigitalFormVariable>(x => x.Form.ID).IsEqualTo(formID));
            foreach (var variable in variables)
                formDataTable.Columns.Add(
                    new CoreColumn
                    {
                        ColumnName = variable.Code,
                        DataType = DigitalFormVariable.DataType(variable.FieldType())
                    }
                );

            FormDataTable = formDataTable;
            Variables = variables;

            AddTable(typeof(CoreTable), formDataTable, true, "Form_Data");
            LinkTable(typeof(T), "ID", typeof(CoreTable), "Parent.ID", childalias: "Form_Data");
        }

        protected override void AfterLoad(IEnumerable<string> requiredtables)
        {
            base.AfterLoad(requiredtables);

            if(FormDataTable == null)
            {
                LoadFormDataTable(FormId ?? ExtractValues<T, Guid>(x => (x as IDigitalFormInstance).Form.ID).FirstOrDefault());
            }

            var idList = ExtractValues<T, Guid>(x => x.ID);
            var jsonLists = ExtractValues<T, string>(x => (x as IDigitalFormInstance).FormData);
            var formDatas = jsonLists.Select(x => Serialization.Deserialize<Dictionary<string, object>>(x));
            foreach (var (i, formData) in formDatas.Select((x, i) => new Tuple<int, Dictionary<string, object>>(i, x)))
            {
                var formRow = FormDataTable.NewRow();
                formRow["Parent.ID"] = idList[i];
                if(formData != null)
                {
                    foreach (var key in formData.Keys)
                    {
                        var variable = Variables.FirstOrDefault(x => string.Equals(x.Code, key));
                        if (variable != null)
                            formRow[key] = variable.ParseValue(formData[key]);
                    }
                }
                FormDataTable.Rows.Add(formRow);
            }

            Load(typeof(CoreTable), FormDataTable, requiredtables, "Form_Data");
        }
    }
}