using Microsoft.AspNetCore.Mvc;
using Sarand.Net.Standard.Base.App;
using Sarand.Net.Standard.Base.Bus;
using Sarand.Net.Standard.Base.Core;
using Sarand.Net.Standard.Base.Dbas;
using Sarand.Net.Standard.Base.Helpers;
using Sarand.Net.Standard.Base.Procs;
using Sarand.Net.Standard.Base.Utils;
using Sarand.Net.Standard.Dbas.Data;
using Sarand.Net.Standard.Dbas.Proc;
using Saxonite.Net.Core.Web.Admin.Models;
using Saxonite.Net.Standard.Base.App;
using Saxonite.Net.Standard.Base.Bus;
using Saxonite.Net.Standard.Dbas.App;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Threading.Tasks;

namespace Saxonite.Net.Core.Web.Admin.Controllers.System
{
	//=======================================================================
	// System - Ajax - Database controller
	//=======================================================================
	partial class SystemController
	{
		//-------------------------------------------------------------------
		// Database data.
		private class DatabaseTableData
		{
			public String SchemaName { get; set; }
			public String TableName { get; set; }
			public String QualifiedName { get; set; }
			public int RowCount { get; set; }
			public int ColumnCount { get; set; }
			public int IndexCount { get; set; }
		}

		//-------------------------------------------------------------------
		// Get Database Table List ajax request.
		//-------------------------------------------------------------------
		private class AjaxResponse_DatabaseTableList : AjaxResponse_Data
		{
			// Construction.
			public AjaxResponse_DatabaseTableList(SaxModel_Admin model) : base(model) { }
			// Table list.
			public List<DatabaseTableData> Tables { get; } = new List<DatabaseTableData>();
		}
		//-------------------------------------------------------------------
		[HttpPost]
		[Route("System/Ajax/GetDatabaseTables")]
		public IActionResult Ajax_GetDatabaseTables(Model_System model)
		{
			String fn = GetType().Name + ".Ajax_GetDatabaseTables";
			String messageTitle = Localiser["system.caption.database"];
			AjaxResponse_DatabaseTableList responseData = new AjaxResponse_DatabaseTableList(model);

			// Validate session.
			if (!ValidUserSession)
				return GetAjaxResult_InvalidSession(responseData);

			// Record disposable items as they are created so all can be disposed when needed.
			using (DisposableCollection<SacsDisposable> disposableItems = new DisposableCollection<SacsDisposable>())
			{
				// Database connection.
				Sax.Database databaseInstance = EnumUtil.ParseEnum(StringUtil.EmptyOnNull(model.DatabaseFilter.Instance), Sax.Database.Core);
				ISacsDatabase db = App.GetDatabase(SessionContext, databaseInstance);

				// Database table row counts.
				Dictionary<String, int> tableRowCounts = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase);
				String query =
					"SELECT QUOTENAME(SCHEMA_NAME(sOBJ.schema_id)) + '.' + QUOTENAME(sOBJ.name) As [TableName], SUM(sPTN.Rows) As [RowCount] " +
					"FROM sys.objects AS sOBJ " +
					"INNER JOIN sys.partitions AS sPTN ON sOBJ.object_id = sPTN.object_id " +
					"WHERE sOBJ.type = 'U' AND sOBJ.is_ms_shipped = 0x0 AND index_id< 2 /*Index Id: 0:Heap,1:Clustered*/ " +
					"GROUP BY sOBJ.schema_id, sOBJ.name";
				using (DbResultSet dbResultSet = DbResultSet_DataReader.ExecuteQuery(db, query))
				{
					while (dbResultSet != null && dbResultSet.NextRecord())
					{
						tableRowCounts.Add(dbResultSet.GetRecordValues().GetValue("TableName").ToString(), (int)dbResultSet.GetRecordValues().GetValue("RowCount").AsLong());
					}
				}

				// Database tables.
				List<DbDfnTable> tableDfns = db.GetTableDfns();
				foreach (DbDfnTable tableDfn in tableDfns.OrderBy(item => item.Name))
				{
					// Filter by table name.
					if (!StringUtil.IsEmpty(model.DatabaseFilter.Search) && !tableDfn.Name.ContainsCI(model.DatabaseFilter.Search))
						continue;

					DatabaseTableData tableData = new DatabaseTableData();
					tableData.SchemaName = tableDfn.Schema;
					tableData.TableName = tableDfn.Name;
					tableData.QualifiedName = tableDfn.QualifiedName;
					tableData.ColumnCount = tableDfn.ColumnCount;
					tableData.IndexCount = tableDfn.IndexCount;

					// Row count.
					tableData.RowCount = tableRowCounts.GetValueOrDefault(tableDfn.QuotedQualifiedName, 0);

					responseData.Tables.Add(tableData);
				}
			}

			// Complete response.
			responseData.Success = true;
			return Json(responseData);
		}

		//-------------------------------------------------------------------
		// Validate Database Schema ajax request.
		//-------------------------------------------------------------------
		private class DbSchemaItemResponseData
		{
			public int Id { get; set; }
			public String TableName { get; set; }
			public String ColumnName { get; set; }
			public int ColumnPosition { get; set; }
			public String IndexName { get; set; }
			public String Comment { get; set; }
		}
		private class AjaxResponse_ValidateDatabaseSchema : AjaxResponse_Data
		{
			// Construction.
			public AjaxResponse_ValidateDatabaseSchema(SaxModel_Admin model) : base(model) { }
			// Database instance.
			public String Instance { get; set; }
			// Schema validation list.
			public List<DbSchemaItemResponseData> Items { get; } = new List<DbSchemaItemResponseData>();
		}
		//-------------------------------------------------------------------
		[HttpPost]
		[Route("System/Ajax/ValidateDatabaseSchema")]
		public IActionResult Ajax_ValidateDatabaseSchema(Model_System model)
		{
			String fn = GetType().Name + ".Ajax_ValidateDatabaseSchema";
			String messageTitle = Localiser["system.caption.database"];
			AjaxResponse_ValidateDatabaseSchema responseData = new AjaxResponse_ValidateDatabaseSchema(model);

			// Validate session.
			if (!ValidUserSession)
				return GetAjaxResult_InvalidSession(responseData);

			// Record disposable items as they are created so all can be disposed when needed.
			using (DisposableCollection<SacsDisposable> disposableItems = new DisposableCollection<SacsDisposable>())
			{

				// Database instance.
				Sax.Database databaseInstance = EnumUtil.ParseEnum(StringUtil.EmptyOnNull(model.DatabaseFilter.Instance), Sax.Database.Unknown);
				if (databaseInstance <= 0)
					return Json(responseData.SetMessage(messageTitle, "Database instance must be specified"));
				responseData.Instance = databaseInstance.ToString();

				// Database connection.
				ISacsDatabase db = App.GetDatabase(SessionContext, databaseInstance);
				if (db == null)
					return Json(responseData.SetMessage(messageTitle, "Unrecognised database instance specified: " + model.DatabaseFilter.Instance));

				// Retrieve XML database schema definition.
				var assembly = typeof(SaxSystem_Dbas).GetTypeInfo().Assembly;
				String xmlSchema = SacsResourceHelper.GetManifestResourceAsText(assembly, "", "SaxDbDfn_" + databaseInstance.ToString() + ".xml");
				if (StringUtil.IsEmpty(xmlSchema))
					return Json(responseData.SetMessage(messageTitle, "Failed to extract XML schema definition."));

				// Extract schema from XML definition.
				SaDbProcess_ConvertDbSchema.Config cfgSchemaConvert = new SaDbProcess_ConvertDbSchema.Config();
				SaDbProcess_ConvertDbSchema procSchemaConvert = new SaDbProcess_ConvertDbSchema(cfgSchemaConvert);
				List<DbDfnTable> tables = procSchemaConvert.ConvertXmlToTables(xmlSchema);
				if (procSchemaConvert.HasErrorMessage())
					return Json(responseData.SetMessage(messageTitle, "Failed to convert XML schema: " + procSchemaConvert.GetErrorMessage()));

				SaDbProcess_CompareDatabaseSchemas.Config cfgSchemaCompare = new SaDbProcess_CompareDatabaseSchemas.Config(tables, db);
				cfgSchemaCompare.HideIdenticalObjects = true;
				cfgSchemaCompare.IgnorePosition = true;
				SaDbProcess_CompareDatabaseSchemas procSchemaCompare = new SaDbProcess_CompareDatabaseSchemas(cfgSchemaCompare);
				procSchemaCompare.OnSchemaComparisonItemAdded += OnSchemaComparisonItemAdded;
				procSchemaCompare.RunProcess();

				List<SaDbProcess_CompareDatabaseSchemas.SchemaComparisonItem> schemaComparisonItems = procSchemaCompare.GetSchemaComparisonItems();
				foreach (SaDbProcess_CompareDatabaseSchemas.SchemaComparisonItem schemaComparisonItem in schemaComparisonItems)
				{
					DbSchemaItemResponseData item = new DbSchemaItemResponseData()
					{
						Id = schemaComparisonItem.Id,
						TableName = schemaComparisonItem.TableName,
						ColumnName = schemaComparisonItem.ColumnName,
						ColumnPosition = schemaComparisonItem.ColumnPosition,
						IndexName = schemaComparisonItem.IndexName,
						Comment = schemaComparisonItem.Comment
					};
					responseData.Items.Add(item);
				}
			}

			// Complete response.
			responseData.Success = true;
			return Json(responseData);
		}

		// Processing events.
		public void OnSchemaComparisonItemAdded(object sender, SaDbProcess_CompareDatabaseSchemas.SchemaComparisonItemAddedEventArgs e)
		{
			SaDbProcess_CompareDatabaseSchemas proc = sender as SaDbProcess_CompareDatabaseSchemas;
		}

		//-------------------------------------------------------------------
		// Database Table ajax request.
		//-------------------------------------------------------------------
		private class AjaxResponseData_Table
		{
			public AjaxResponseData_Table(DbDfnTable tableDfn)
			{
				Schema = tableDfn.Schema;
				Name = tableDfn.Name;
				if (!StringUtil.IsEmpty(tableDfn.Remarks))
					Remarks = tableDfn.Remarks;
				foreach (DbDfnColumn columnDfn in tableDfn.Columns)
					Columns.Add(new AjaxResponseData_Column(columnDfn));
				foreach (DbDfnIndex indexDfn in tableDfn.Indices)
					Indices.Add(new AjaxResponseData_Index(indexDfn));
			}
			public String Schema { get; }
			public String Name { get; }
			public String QualifiedName { get { return (!StringUtil.IsEmpty(Schema) ? Schema + "." : "") + Name; } }
			public String QuotedQualifiedName { get { return (!StringUtil.IsEmpty(Schema) ? "[" + Schema + "]." : "") + "[" + Name + "]"; } }
			public String Remarks { get; set; } = String.Empty;
			public List<AjaxResponse_Data.ItemLabelValue> Properties { get; } = new List<AjaxResponse_Data.ItemLabelValue>();
			public List<AjaxResponseData_Column> Columns { get; } = new List<AjaxResponseData_Column>();
			public List<AjaxResponseData_Index> Indices { get; } = new List<AjaxResponseData_Index>();
		}
		private class AjaxResponseData_Column
		{
			public int Pos { get; }
			public String Name { get; }
			public String Format { get; }
			public String DataTypeName { get; }
			public short? DataTypeNative { get; }
			public String DataTypeNameNative { get; }
			public bool? IsIdentity { get; }
			public long? Size { get; }
			public long? BufferLen { get; }
			public short? DecimalDigits { get; }
			public bool? Nullable { get; }
			public bool? IsNullable { get; }
			public String Remarks { get; }
			public AjaxResponseData_Column(DbDfnColumn columnDfn)
			{
				Pos = columnDfn.Pos;
				Name = columnDfn.Name;
				Format = columnDfn.GetFormat();
				if (!StringUtil.IsEmpty(columnDfn.DataTypeName))
					DataTypeName = columnDfn.DataTypeName;
				if (columnDfn.DataTypeNative > 0)
					DataTypeNative = columnDfn.DataTypeNative;
				if (!StringUtil.IsEmpty(columnDfn.DataTypeNameNative))
					DataTypeNameNative = columnDfn.DataTypeNameNative;
				if (columnDfn.IsIdentity)
					IsIdentity = columnDfn.IsIdentity;
				if (columnDfn.Size > 0)
					Size = columnDfn.Size;
				if (columnDfn.BufferLen > 0)
					BufferLen = columnDfn.BufferLen;
				if (columnDfn.DecimalDigits > 0)
					DecimalDigits = columnDfn.DecimalDigits;
				if (columnDfn.Nullable == DbColumnNullable.Nullable)
					Nullable = true;
				if (columnDfn.IsNullable)
					IsNullable = columnDfn.IsNullable;
				if (!StringUtil.IsEmpty(columnDfn.Remarks))
					Remarks = columnDfn.Remarks;
			}
		}
		private class AjaxResponseData_Index
		{
			public String Name { get; }
			public int? IndexType { get; }
			public bool? Unique { get; }
			public bool? Primary { get; }
			public bool? Clustered { get; }
			public bool? Nullable { get; }
			public int? Pages { get; }
			public int? UniqueValues { get; }
			public List<AjaxResponseData_IndexColumn> Columns { get; } = new List<AjaxResponseData_IndexColumn>();
			public AjaxResponseData_Index(DbDfnIndex indexDfn)
			{
				Name = indexDfn.Name;
				if (indexDfn.IndexType > 0)
					IndexType = indexDfn.IndexType;
				if (indexDfn.Unique)
					Unique = indexDfn.Unique;
				if (indexDfn.Primary)
					Primary = indexDfn.Primary;
				if (indexDfn.Clustered)
					Clustered = indexDfn.Clustered;
				if (indexDfn.Nullable)
					Nullable = indexDfn.Nullable;
				if (indexDfn.Pages > 0)
					Pages = indexDfn.Pages;
				if (indexDfn.UniqueValues > 0)
					UniqueValues = indexDfn.UniqueValues;
				foreach (DbDfnIndexColumn indexColumnDfn in indexDfn.Columns)
					Columns.Add(new AjaxResponseData_IndexColumn(indexColumnDfn));
			}
		}
		private class AjaxResponseData_IndexColumn
		{
			public short Seq { get; }
			public String Name { get; }
			public bool? Desc { get; }
			public AjaxResponseData_IndexColumn(DbDfnIndexColumn indexColumnDfn)
			{
				Seq = indexColumnDfn.Seq;
				Name = indexColumnDfn.Name;
				if (!indexColumnDfn.Ascend)
					Desc = true;
			}
		}
		private class AjaxResponse_DatabaseTable : AjaxResponse_Data
		{
			// Construction.
			public AjaxResponse_DatabaseTable(SaxModel_Admin model) : base(model) { }
			// Database table.
			public String PopupTitle { get; set; }
			public AjaxResponseData_Table Table { get; set; }
		}
		//-------------------------------------------------------------------
		[HttpPost]
		[Route("System/Ajax/GetDatabaseTable")]
		public IActionResult Ajax_GetDatabaseTable(Model_System model)
		{
			String fn = GetType().Name + ".Ajax_GetDatabaseTable";
			String messageTitle = Localiser["system.caption.database"];
			AjaxResponse_DatabaseTable responseData = new AjaxResponse_DatabaseTable(model);

			// Validate session.
			if (!ValidUserSession)
				return GetAjaxResult_InvalidSession(responseData);

			// Record disposable items as they are created so all can be disposed when needed.
			using (DisposableCollection<SacsDisposable> disposableItems = new DisposableCollection<SacsDisposable>())
			{

				// Parameters.
				if (StringUtil.IsEmpty(model.DatabaseTable.Name))
					return Json(responseData.SetMessage(messageTitle, "Table name must be supplied."));

				// Database instance.
				Sax.Database databaseInstance = EnumUtil.ParseEnum(StringUtil.EmptyOnNull(model.DatabaseTable.Instance), Sax.Database.Unknown);
				if (databaseInstance <= 0)
					return Json(responseData.SetMessage(messageTitle, "Database instance must be specified"));

				// Database connection.
				ISacsDatabase db = App.GetDatabase(SessionContext, databaseInstance);

				// Table definition.
				DbDfnTable tableDfn = db.GetTableDfn(model.DatabaseTable.Name, true);
				if (tableDfn == null)
					return Json(responseData.SetMessage(messageTitle, "Invalid Table name supplied."));

				// Populate table response.
				responseData.Table = new AjaxResponseData_Table(tableDfn);
				responseData.PopupTitle = Localiser["label.table"] + ": " + tableDfn.Name;

				// Database sizing.
				String query = "Exec sp_SpaceUsed [" + tableDfn.QualifiedName + "];";
				using (DbResultSet dbResultSet = DbResultSet_DataReader.ExecuteQuery(db, query))
				{
					if (dbResultSet != null && dbResultSet.NextRecord())
					{
						// Row count.
						long rows = StringUtil.ToLong(dbResultSet.GetRecordValues().GetValue("rows").ToString());
						if (rows > 0)
							responseData.Table.Properties.Add(new AjaxResponse_Data.ItemLabelValue() { Label = "Rows", Value = rows.ToString() });
						// Reserved space.
						String reserved = dbResultSet.GetRecordValues().GetValue("reserved").AsString();
						if (!StringUtil.IsEmpty(reserved))
							responseData.Table.Properties.Add(new AjaxResponse_Data.ItemLabelValue() { Label = "Reserved", Value = reserved });
						// Data space.
						String data = dbResultSet.GetRecordValues().GetValue("data").AsString();
						if (!StringUtil.IsEmpty(data))
							responseData.Table.Properties.Add(new AjaxResponse_Data.ItemLabelValue() { Label = "Data", Value = data });
						// Index space.
						String index = dbResultSet.GetRecordValues().GetValue("index_size").AsString();
						if (!StringUtil.IsEmpty(index))
							responseData.Table.Properties.Add(new AjaxResponse_Data.ItemLabelValue() { Label = "Indices", Value = index });
						// Unused space.
						String unused = dbResultSet.GetRecordValues().GetValue("unused").AsString();
						if (!StringUtil.IsEmpty(unused))
							responseData.Table.Properties.Add(new AjaxResponse_Data.ItemLabelValue() { Label = "Unused", Value = unused });
					}
				}
			}

			// Complete response.
			responseData.Success = true;
			return Json(responseData);
		}

		//-------------------------------------------------------------------
	}
	//=======================================================================
}