using System.Collections.Generic;
using System.Linq;
using AyaNova.Biz;
using Newtonsoft.Json.Linq;
using AyaNova.Api.ControllerHelpers;
using Microsoft.Extensions.Logging;
using AyaNova.Models;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using EnumsNET;

namespace AyaNova.DataList
{
    internal static class DataListFetcher
    {

        ////////////////////////////////////////////////
        // Get the data list data requested
        //
        //
        internal static async Task<ApiDataListResponse> GetResponseAsync(AyContext ct, DataListTableOptions dataListTableOptions, AuthorizationRoles userRoles, ILogger log, long userId)
        {

            var DataList = DataListFactory.GetAyaDataList(dataListTableOptions.DataListKey);

            //was the name not found as a list?
            if (DataList == null)
                throw new System.ArgumentOutOfRangeException($"DataList \"{dataListTableOptions.DataListKey}\" specified does not exist");


            //check rights
            if (!userRoles.HasAnyFlags(DataList.AllowedRoles))
                throw new System.UnauthorizedAccessException("User roles insufficient for this datalist");

            DataList.SetListOptionDefaultsIfNecessary(dataListTableOptions);


            //STATIC filter options from server
            List<DataListFilterOption> StaticServerFilterOptions = null;
            if (DataList is IAyaDataListServerCriteria)
                StaticServerFilterOptions = ((IAyaDataListServerCriteria)DataList).DataListServerCriteria(userId, userRoles, dataListTableOptions);


            // //Get the public field key names in a list from the listview
            // List<string> PublicListViewFieldList = listOptions.Columns;

            //Get the combination of all unique fields from both StaticServerFilterOptions and listOptions   
            //NOTE: this assumes no list options filter colums that don't exist in listoptions.columns       
            var AllUniqueFieldKeysRequiredForQuery = dataListTableOptions.Columns.Union(StaticServerFilterOptions.Select(z => z.Column).ToList()).ToList();

            //Add the internal filters into the listoptions existing filters
            //NOTE: There is currently no overlap between internal filtered columns and filters coming from the client
            foreach (DataListFilterOption dfo in StaticServerFilterOptions)
                dataListTableOptions.Filter.Add(dfo);

            //BUILD THE QUERY     

            //SELECT CLAUSE            
            var qSelect = DataListSqlSelectBuilder.Build(DataList.FieldDefinitions, AllUniqueFieldKeysRequiredForQuery);

            //FROM CLAUSE             
            var qFrom = DataList.SQLFrom;

            var qWhere = string.Empty;
            var qOrderBy = string.Empty;

            //WHERE CLAUSE - FILTER            
            qWhere = DataListSqlFilterCriteriaBuilder.DataFilterToSQLCriteria(DataList.FieldDefinitions, dataListTableOptions);

            //ORDER BY CLAUSE - SORT 
            //BUILD ORDER BY 
            qOrderBy = DataListSqlFilterOrderByBuilder.DataFilterToSQLOrderBy(DataList.FieldDefinitions, dataListTableOptions);

            //LIMIT AND OFFSET CLAUSE - PAGING
            dataListTableOptions.Offset = dataListTableOptions.Offset ?? DataListTableOptions.DefaultOffset;
            dataListTableOptions.Limit = dataListTableOptions.Limit ?? DataListTableOptions.DefaultLimit;
            var qLimitOffset = $"LIMIT {dataListTableOptions.Limit} OFFSET {dataListTableOptions.Offset}";

            //PUT IT ALL TOGETHER
            string qDataQuery = string.Empty;
            string qTotalRecordsQuery = string.Empty;

            qDataQuery = $"{qSelect.Select} {qFrom} {qWhere} {qOrderBy} {qLimitOffset}".Replace("  ", " ");
            qTotalRecordsQuery = $"SELECT COUNT(*) {qFrom} {qWhere}".Replace("  ", " ");

            //RETURN OBJECTS                  
            int returnRowColumnCount = dataListTableOptions.Columns.Count();
            List<List<AyaFieldData>> rows = new List<List<AyaFieldData>>();
            long totalRecordCount = 0;

            //QUERY THE DB
            using (var command = ct.Database.GetDbConnection().CreateCommand())
            {
                await ct.Database.OpenConnectionAsync();

                //GET DATA RETURN ROWS
                command.CommandText = qDataQuery;
                try
                {
                    using (var dr = await command.ExecuteReaderAsync())
                    {
                        while (dr.Read())
                        {
                            List<AyaFieldData> row = new List<AyaFieldData>(returnRowColumnCount);


                            //INSERT REMAINING FIELDS FROM TEMPLATE INTO THE RETURN ROWS LIST
                            foreach (string TemplateField in dataListTableOptions.Columns)
                            {

                                //get the AyaObjectFieldDefinition
                                AyaDataListFieldDefinition f = DataList.FieldDefinitions.FirstOrDefault(z => z.FieldKey == TemplateField);
                                if (f.IsCustomField)
                                {

                                    AyaFieldData AyaField = new AyaFieldData();
                                    var cust = dr.GetString(qSelect.map[f.GetSqlValueColumnName()]);
                                    if (!string.IsNullOrWhiteSpace(cust))
                                    {
                                        JObject j = JObject.Parse(cust);
                                        //convert field name to cust name then get value
                                        var InternalCustomFieldName = AyaFormFieldDefinitions.TranslateLTCustomFieldToInternalCustomFieldName(TemplateField);
                                        //Sometimes a custom field is specified but doesn't exist in the collection so don't assume it's there
                                        // AyaField.v = j[InternalCustomFieldName].Value<object>();
                                        JToken o = j[InternalCustomFieldName];
                                        if (o != null)
                                            AyaField.v = o.Value<object>();
                                        else
                                            AyaField.v = null;

                                        row.Add(AyaField);
                                    }

                                    /*
                                    TODO: Custom field handling
                                    GetName works just not with multipart identifiers
                                    I could force naming by making all fields and AS, or
                                    I could map the ordinal when generating the Select fields so that I have a map to refer to here
                                    mapping in advance actually makes a lot of sense, then no more of this fragility of going by pointer index and hoping for the best
                                    it would just be premapped out.

                                    dr.GetOrdinal(f.SqlValueColumnName)
    'dr.GetOrdinal(f.SqlValueColumnName)' threw an exception of type 'System.IndexOutOfRangeException'
    f.SqlValueColumnName
    "awidget.customfields"
    dr.GetName(nCurrentColumnPointer)
    "customfields"
    dr.GetOrdinal("customfields");
    5

                                    */
                                }
                                else
                                {
                                    AyaFieldData AyaField = new AyaFieldData();
                                    AyaField.v = dr.GetValue(qSelect.map[f.GetSqlValueColumnName()]);

                                    if (f.IsRowId)
                                    {
                                        AyaField.rid = true;
                                    }
                                    else
                                    {
                                        AyaField.rid = null;
                                    }

                                    if (f.SqlIdColumnName != null)
                                    {
                                        var ordinal = qSelect.map[f.SqlIdColumnName];
                                        if (!await dr.IsDBNullAsync(ordinal))
                                            AyaField.i = dr.GetInt64(ordinal);
                                    }

                                    if (f.SqlAyTypeColumnName != null)
                                    {
                                        var ordinal = qSelect.map[f.SqlAyTypeColumnName];
                                        if (!await dr.IsDBNullAsync(ordinal))
                                            AyaField.ot = dr.GetInt32(ordinal);
                                    }

                                    if (f.SqlColorColumnName != null)
                                    {
                                        var ordinal = qSelect.map[f.SqlColorColumnName];
                                        if (!await dr.IsDBNullAsync(ordinal))
                                            AyaField.clr = dr.GetString(ordinal);
                                    }

                                    row.Add(AyaField);
                                }
                            }
                            rows.Add(row);
                        }
                    }

                    //GET TOTAL RECORD COUNT
                    command.CommandText = qTotalRecordsQuery;
                    using (var dr = await command.ExecuteReaderAsync())
                    {
                        if (dr.Read())
                        {
                            totalRecordCount = dr.GetInt64(0);
                        }
                    }
                }
                catch (Npgsql.PostgresException e)
                {
                    //log out the exception and the query
                    log.LogError("DataListFetcher:GetResponseAsync query failed.  Data Query was:");
                    log.LogError(qDataQuery);
                    log.LogError("Count Query was:");
                    log.LogError(qTotalRecordsQuery);
                    log.LogError(e, "DB Exception");
                    throw new System.Exception("DataListFetcher:GetResponseAsync - Query failed see log");

                }
                catch (System.Exception e)
                {
                    //ensure any other type of exception gets surfaced properly
                    //log out the exception and the query
                    log.LogError("DataListFetcher:GetResponseAsync unexpected failure.  Data Query was:");
                    log.LogError(qDataQuery);

                    log.LogError(e, "Exception");
                    throw new System.Exception("DataListFetcher:GetResponseAsync - unexpected failure see log");
                }
            }



            //BUILD THE COLUMNS RETURN PROPERTY JSON FRAGMENT          
            Newtonsoft.Json.Linq.JArray ColumnsJSON = null;

            ColumnsJSON = DataList.GenerateReturnListColumns(dataListTableOptions.Columns);//<<<-----this next

            return new ApiDataListResponse(rows, totalRecordCount, ColumnsJSON);

        }


        /////////////////////////////////////////////////////////////////
        // Get a list of id's of the datalist results for reporting
        //
        //
        //internal static async Task<long[]> GetIdListResponseAsync(string dataListKey, string listView, string metaListView, AyContext ct, AuthorizationRoles userRoles, ILogger log, long userId)
        internal static async Task<long[]> GetIdListResponseAsync(AyContext ct, DataListSelectionOptions dataListSelectionOptions, AuthorizationRoles userRoles, ILogger log, long userId)
        {
            var DataList = DataListFactory.GetAyaDataList(dataListSelectionOptions.DataListKey);
            //was the name not found as a list?
            if (DataList == null)
                throw new System.ArgumentOutOfRangeException($"DataList \"{dataListSelectionOptions.DataListKey}\" specified does not exist");



            //check rights
            if (!userRoles.HasAnyFlags(DataList.AllowedRoles))
                throw new System.UnauthorizedAccessException("User roles insufficient for this datalist");

            // //do we need to default the listView?
            // if (string.IsNullOrWhiteSpace(listView))
            //     listView = DataList.DefaultListView;

            DataList.SetListOptionDefaultsIfNecessary(dataListSelectionOptions);

            // //parse the list view     
            // var ListViewArray = JArray.Parse(listView);


            // //Hard coded extra criteria from server end
            // if (DataList is IAyaDataListServerCriteria)
            // {
            //     var ServerCriteriaListView = JArray.Parse(((IAyaDataListServerCriteria)DataList).DataListServerCriteria(await ct.User.AsNoTracking().FirstOrDefaultAsync(z => z.Id == userId), ct));
            //     foreach (JToken jt in ServerCriteriaListView)
            //         ListViewArray.Add(jt);
            // }

            //STATIC filter options from server
            List<DataListFilterOption> StaticServerFilterOptions = null;
            if (DataList is IAyaDataListServerCriteria)
                StaticServerFilterOptions = ((IAyaDataListServerCriteria)DataList).DataListServerCriteria(userId, userRoles, dataListSelectionOptions);


            // //Hard coded extra criteria from Client end
            // //parse and combine any additional listview hard coded from Client UI
            // var MetaListViewArray = JArray.Parse(metaListView ?? "[]");
            // foreach (JToken jt in MetaListViewArray)
            //     ListViewArray.Add(jt);

            // //Get the field key names in a list from the listview
            // List<string> ListViewFieldList = DataList.GetFieldListFromListView(ListViewArray);

            //BUILD THE QUERY                     
            //SELECT FRAGMENT COLUMNS FROM TEMPLATE               
            var SelectBuild = DataListSqlSelectBuilder.BuildForReportIdListOnly(DataList.FieldDefinitions);

            //FROM CLAUSE             
            var qFrom = DataList.SQLFrom;

            var qWhere = string.Empty;
            var qOrderBy = string.Empty;

            //WHERE CLAUSE - FILTER            
            qWhere = DataListSqlFilterCriteriaBuilder.DataFilterToSQLCriteria(DataList.FieldDefinitions, dataListSelectionOptions);

            //ORDER BY CLAUSE - SORT           
            qOrderBy = DataListSqlFilterOrderByBuilder.DataFilterToSQLOrderBy(DataList.FieldDefinitions, dataListSelectionOptions);

            //PUT IT ALL TOGETHER
            string qDataQuery = string.Empty;

            qDataQuery = $"{SelectBuild.Select} {qFrom} {qWhere} {qOrderBy} ".Replace("  ", " ");

            //RETURN OBJECTS                  
            var retList = new List<long>();

            //GET ID COLUMN ORDINAL
            int IDColumnOrdinal = 0;

            //NOTE: assuming change of code means id column is *always* the zeroth column

            // foreach (string TemplateField in ListViewFieldList)
            // {
            //     //get the AyaObjectFieldDefinition
            //     AyaDataListFieldDefinition f = DataList.FieldDefinitions.FirstOrDefault(z => z.FieldKey == TemplateField);
            //     if (f.IsRowId)
            //     {
            //         IDColumnOrdinal = SelectBuild.map[f.SqlIdColumnName];
            //         break;
            //     }
            // }

            using (var command = ct.Database.GetDbConnection().CreateCommand())
            {
                await ct.Database.OpenConnectionAsync();
                command.CommandText = qDataQuery;
                try
                {
                    using (var dr = await command.ExecuteReaderAsync())
                    {
                        while (dr.Read())
                        {
                            if (!dr.IsDBNull(IDColumnOrdinal))
                                retList.Add(dr.GetInt64(IDColumnOrdinal));
                        }
                    }
                }
                catch (Npgsql.PostgresException e)
                {
                    //log out the exception and the query
                    log.LogError("DataListFetcher:GetIdListResponseAsync query failed unexpectedly.  IDList Query was:");
                    log.LogError(qDataQuery);

                    log.LogError(e, "DB Exception");
                    throw new System.Exception("DataListFetcher:GetIdListResponseAsync - Query failed see log");
                }
                catch (System.Exception e)
                {
                    //ensure any other type of exception gets surfaced properly
                    //log out the exception and the query
                    log.LogError("DataListFetcher:GetIdListResponseAsync unexpected failure.  IDList Query was:");
                    log.LogError(qDataQuery);

                    log.LogError(e, "Exception");
                    throw new System.Exception("DataListFetcher:GetIdListResponseAsync - unexpected failure see log");
                }
            }
            return retList.ToArray();
        }


    }//eoc
}//eons