using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;
using HeuristicLab.MainForm;
using HeuristicLab.MainForm.WindowsForms;
using System.Windows.Forms;
using HeuristicLab.Common;

namespace HeuristicLab.Data.MoveVectorData.Views
{
    [View("Stacking Area View")]
    [Content(typeof(StackingArea), IsDefaultView = true)]
    public partial class StackingAreaView : AsynchronousContentView
    {
        protected int[] virtualRowIndices;

        public new IStringConvertibleMatrix Content
        {
            get { return (IStringConvertibleMatrix)base.Content; }
            set { base.Content = value; }
        }

        public DataGridView DataGridView
        {
            get { return dataGridView; }
        }

        public override bool ReadOnly
        {
            get
            {
                if ((Content != null) && Content.ReadOnly) return true;
                return base.ReadOnly;
            }
            set { base.ReadOnly = value; }
        }

        public StackingAreaView()
        {
            InitializeComponent();
        }

        protected override void DeregisterContentEvents()
        {
            Content.ItemChanged -= new EventHandler<EventArgs<int, int>>(Content_ItemChanged);
            Content.Reset -= new EventHandler(Content_Reset);
            Content.ColumnNamesChanged -= new EventHandler(Content_ColumnNamesChanged);
            Content.RowNamesChanged -= new EventHandler(Content_RowNamesChanged);
            base.DeregisterContentEvents();
        }
        protected override void RegisterContentEvents()
        {
            base.RegisterContentEvents();
            Content.ItemChanged += new EventHandler<EventArgs<int, int>>(Content_ItemChanged);
            Content.Reset += new EventHandler(Content_Reset);
            Content.ColumnNamesChanged += new EventHandler(Content_ColumnNamesChanged);
            Content.RowNamesChanged += new EventHandler(Content_RowNamesChanged);
        }

        protected override void OnContentChanged()
        {
            base.OnContentChanged();
            if (Content == null)
            {
                dataGridView.Rows.Clear();
                dataGridView.Columns.Clear();
                virtualRowIndices = new int[0];
            }
            else if (!dataGridView.IsCurrentCellInEditMode)
            {
                UpdateData();
            }
        }

        protected override void SetEnabledStateOfControls()
        {
            base.SetEnabledStateOfControls();
            dataGridView.Enabled = Content != null;
            dataGridView.ReadOnly = ReadOnly;
        }

        protected virtual void UpdateData()
        {
            virtualRowIndices = Enumerable.Range(0, Content.Rows).Reverse().ToArray();

            if (Content.Columns == 0 && dataGridView.ColumnCount != Content.Columns && !Content.ReadOnly)
                Content.Columns = dataGridView.ColumnCount;
            else {
                DataGridViewColumn[] columns = new DataGridViewColumn[Content.Columns];
                for (int i = 0; i < columns.Length; ++i)
                {
                    var column = new DataGridViewTextBoxColumn();
                    column.FillWeight = 1;
                    columns[i] = column;
                }
                dataGridView.Columns.Clear();
                dataGridView.Columns.AddRange(columns);
            }

            //DataGridViews with rows but no columns are not allowed !
            if (Content.Rows == 0 && dataGridView.RowCount != Content.Rows && !Content.ReadOnly)
                Content.Rows = dataGridView.RowCount;
            else
                dataGridView.RowCount = Content.Rows;

            UpdateColumnHeaders();
            UpdateRowHeaders();

            dataGridView.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.ColumnHeader);
            dataGridView.AutoResizeRowHeadersWidth(DataGridViewRowHeadersWidthSizeMode.AutoSizeToDisplayedHeaders);
            dataGridView.Enabled = true;
        }

        public virtual void UpdateColumnHeaders()
        {
            HashSet<string> invisibleColumnNames = new HashSet<string>(dataGridView.Columns.OfType<DataGridViewColumn>()
            .Where(c => !c.Visible && !string.IsNullOrEmpty(c.HeaderText)).Select(c => c.HeaderText));

            for (int i = 0; i < dataGridView.ColumnCount; i++)
            {
                if (i < Content.ColumnNames.Count())
                    dataGridView.Columns[i].HeaderText = Content.ColumnNames.ElementAt(i);
                else
                    dataGridView.Columns[i].HeaderText = "Stack " + (i + 1 - 1);
                dataGridView.Columns[i].Visible = !invisibleColumnNames.Contains(dataGridView.Columns[i].HeaderText);
            }
        }
        public virtual void UpdateRowHeaders()
        {
            int index = dataGridView.FirstDisplayedScrollingRowIndex;
            if (index == -1) index = 0;
            int updatedRows = 0;
            int count = dataGridView.DisplayedRowCount(true);

            while (updatedRows < count)
            {
                if (virtualRowIndices[index] < Content.RowNames.Count())
                    dataGridView.Rows[index].HeaderCell.Value = Content.RowNames.ElementAt(virtualRowIndices[index]);
                else
                    dataGridView.Rows[index].HeaderCell.Value = "Tier " + (count - index - 1);
                if (dataGridView.Rows[index].Visible)
                    updatedRows++;
                index++;
            }
        }

        private void Content_RowNamesChanged(object sender, EventArgs e)
        {
            if (InvokeRequired)
                Invoke(new EventHandler(Content_RowNamesChanged), sender, e);
            else
                UpdateRowHeaders();
        }
        private void Content_ColumnNamesChanged(object sender, EventArgs e)
        {
            if (InvokeRequired)
                Invoke(new EventHandler(Content_ColumnNamesChanged), sender, e);
            else
                UpdateColumnHeaders();
        }
        private void Content_ItemChanged(object sender, EventArgs<int, int> e)
        {
            if (InvokeRequired)
                Invoke(new EventHandler<EventArgs<int, int>>(Content_ItemChanged), sender, e);
            else
                dataGridView.InvalidateCell(e.Value2, e.Value);
        }
        private void Content_Reset(object sender, EventArgs e)
        {
            if (InvokeRequired)
                Invoke(new EventHandler(Content_Reset), sender, e);
            else
                UpdateData();
        }

        #region DataGridView Events
        protected virtual void dataGridView_CellValidating(object sender, DataGridViewCellValidatingEventArgs e)
        {
            if (!dataGridView.ReadOnly)
            {
                string errorMessage;
                if (Content != null && !Content.Validate(e.FormattedValue.ToString(), out errorMessage))
                {
                    e.Cancel = true;
                    dataGridView.Rows[e.RowIndex].ErrorText = errorMessage;
                }
            }
        }
        protected virtual void dataGridView_CellParsing(object sender, DataGridViewCellParsingEventArgs e)
        {
            if (!dataGridView.ReadOnly)
            {
                string value = e.Value.ToString();
                int rowIndex = virtualRowIndices[e.RowIndex];
                e.ParsingApplied = Content != null && Content.SetValue(value, rowIndex, e.ColumnIndex);
                if (e.ParsingApplied) e.Value = Content.GetValue(rowIndex, e.ColumnIndex);
            }
        }
        private void dataGridView_CellEndEdit(object sender, DataGridViewCellEventArgs e)
        {
            dataGridView.Rows[e.RowIndex].ErrorText = string.Empty;
        }
        protected virtual void dataGridView_CellValueNeeded(object sender, DataGridViewCellValueEventArgs e)
        {
            if (Content != null && e.RowIndex < Content.Rows && e.ColumnIndex < Content.Columns)
            {
                int rowIndex = virtualRowIndices[e.RowIndex];
                e.Value = Content.GetValue(rowIndex, e.ColumnIndex);
            }
        }

        private void dataGridView_Scroll(object sender, System.Windows.Forms.ScrollEventArgs e)
        {
            this.UpdateRowHeaders();
        }
        private void dataGridView_Resize(object sender, EventArgs e)
        {
            this.UpdateRowHeaders();
        }

        protected virtual void dataGridView_KeyDown(object sender, KeyEventArgs e)
        {
            if (!ReadOnly && e.Control && e.KeyCode == Keys.V)
                PasteValuesToDataGridView();
            else if (e.Control && e.KeyCode == Keys.C)
                CopyValuesFromDataGridView();
        }

        private void CopyValuesFromDataGridView()
        {
            if (dataGridView.SelectedCells.Count == 0) return;
            StringBuilder s = new StringBuilder();
            int minRowIndex = dataGridView.SelectedCells[0].RowIndex;
            int maxRowIndex = dataGridView.SelectedCells[dataGridView.SelectedCells.Count - 1].RowIndex;
            int minColIndex = dataGridView.SelectedCells[0].ColumnIndex;
            int maxColIndex = dataGridView.SelectedCells[dataGridView.SelectedCells.Count - 1].ColumnIndex;

            if (minRowIndex > maxRowIndex)
            {
                int temp = minRowIndex;
                minRowIndex = maxRowIndex;
                maxRowIndex = temp;
            }
            if (minColIndex > maxColIndex)
            {
                int temp = minColIndex;
                minColIndex = maxColIndex;
                maxColIndex = temp;
            }

            bool addRowNames = dataGridView.AreAllCellsSelected(false) && Content.RowNames.Count() > 0;
            bool addColumnNames = dataGridView.AreAllCellsSelected(false) && Content.ColumnNames.Count() > 0;

            //add colum names
            if (addColumnNames)
            {
                if (addRowNames)
                    s.Append('\t');

                DataGridViewColumn column = dataGridView.Columns.GetFirstColumn(DataGridViewElementStates.Visible);
                while (column != null)
                {
                    s.Append(column.HeaderText);
                    s.Append('\t');
                    column = dataGridView.Columns.GetNextColumn(column, DataGridViewElementStates.Visible, DataGridViewElementStates.None);
                }
                s.Remove(s.Length - 1, 1); //remove last tab
                s.Append(Environment.NewLine);
            }

            for (int i = minRowIndex; i <= maxRowIndex; i++)
            {
                if (!dataGridView.Rows[i].Visible) continue;

                int rowIndex = this.virtualRowIndices[i];
                if (addRowNames)
                {
                    s.Append(Content.RowNames.ElementAt(rowIndex));
                    s.Append('\t');
                }

                DataGridViewColumn column = dataGridView.Columns.GetFirstColumn(DataGridViewElementStates.Visible);
                while (column != null)
                {
                    DataGridViewCell cell = dataGridView[column.Index, i];
                    if (cell.Selected)
                    {
                        s.Append(Content.GetValue(rowIndex, column.Index));
                        s.Append('\t');
                    }

                    column = dataGridView.Columns.GetNextColumn(column, DataGridViewElementStates.Visible, DataGridViewElementStates.None);
                }
                s.Remove(s.Length - 1, 1); //remove last tab
                s.Append(Environment.NewLine);
            }
            Clipboard.SetText(s.ToString());
        }

        protected virtual void PasteValuesToDataGridView()
        {
            string[,] values = SplitClipboardString(Clipboard.GetText());
            int rowIndex = 0;
            int columnIndex = 0;
            if (dataGridView.CurrentCell != null)
            {
                rowIndex = virtualRowIndices[dataGridView.CurrentCell.RowIndex];
                columnIndex = dataGridView.CurrentCell.ColumnIndex;
            }
            if (Content.Rows < values.GetLength(1) + rowIndex) Content.Rows = values.GetLength(1) + rowIndex;
            if (Content.Columns < values.GetLength(0) + columnIndex) Content.Columns = values.GetLength(0) + columnIndex;

            for (int row = 0; row < values.GetLength(1); row++)
            {
                for (int col = 0; col < values.GetLength(0); col++)
                {
                    Content.SetValue(values[col, values.GetLength(1) - 1 - row], row + rowIndex, col + columnIndex);
                }
            }
        }
        protected string[,] SplitClipboardString(string clipboardText)
        {
            if (clipboardText.EndsWith(Environment.NewLine))
                clipboardText = clipboardText.Remove(clipboardText.Length - Environment.NewLine.Length);  //remove last newline constant
            string[,] values = null;
            string[] lines = clipboardText.Split(new string[] { Environment.NewLine }, StringSplitOptions.None);
            string[] cells;
            for (int i = 0; i < lines.Length; i++)
            {
                cells = lines[i].Split('\t');
                if (values == null)
                    values = new string[cells.Length, lines.Length];
                for (int j = 0; j < cells.Length; j++)
                    values[j, i] = string.IsNullOrEmpty(cells[j]) ? string.Empty : cells[j];
            }
            return values;
        }

        protected virtual void dataGridView_MouseClick(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            if (Content == null) return;
            if (e.Button == MouseButtons.Right && Content.ColumnNames.Count() != 0)
                contextMenu.Show(MousePosition);
        }
    }
    #endregion
}