using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Windows.Forms;

namespace BoxPacker3D
{
    /// <summary>
    /// Modal dialog for managing the item template database.
    /// Allows adding, editing, and deleting saved item templates.
    /// </summary>
    public class ItemDatabaseEditor : Form
    {
        private ItemDatabase _db;
        private DataGridView _grid;
        private TextBox _txtSearch;
        private Button _btnAdd, _btnEdit, _btnDelete, _btnClose;
        private List<ItemTemplate> _allTemplates = new List<ItemTemplate>();

        public ItemDatabaseEditor(ItemDatabase db)
        {
            _db = db;
            BuildUI();
            LoadData();
        }

        private void BuildUI()
        {
            this.Text = "Správa databázy kusov";
            this.Size = new Size(700, 500);
            this.MinimumSize = new Size(600, 400);
            this.StartPosition = FormStartPosition.CenterParent;
            this.BackColor = Color.FromArgb(30, 30, 40);
            this.AutoScaleMode = AutoScaleMode.Dpi;

            // Bottom panel with Close button (add FIRST for proper docking)
            var pnlBottom = new Panel
            {
                Dock = DockStyle.Bottom,
                Height = 50,
                BackColor = Color.FromArgb(25, 25, 35),
                Padding = new Padding(10, 8, 10, 8)
            };

            _btnClose = MakeButton("✖ Zavrieť", Color.FromArgb(60, 60, 80));
            _btnClose.Dock = DockStyle.Right;
            _btnClose.Width = 120;
            _btnClose.Click += (s, e) => this.Close();
            pnlBottom.Controls.Add(_btnClose);
            this.Controls.Add(pnlBottom);

            // DataGridView (add SECOND so it fills remaining space)
            _grid = new DataGridView
            {
                Dock = DockStyle.Fill,
                BackgroundColor = Color.FromArgb(40, 40, 55),
                GridColor = Color.FromArgb(60, 60, 80),
                BorderStyle = BorderStyle.None,
                RowHeadersVisible = false,
                AllowUserToAddRows = false,
                AllowUserToDeleteRows = false,
                ReadOnly = true,
                SelectionMode = DataGridViewSelectionMode.FullRowSelect,
                MultiSelect = false,
                AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill,
                EnableHeadersVisualStyles = false
            };

            _grid.DefaultCellStyle.BackColor = Color.FromArgb(40, 40, 55);
            _grid.DefaultCellStyle.ForeColor = Color.White;
            _grid.DefaultCellStyle.SelectionBackColor = Color.FromArgb(60, 100, 160);
            _grid.DefaultCellStyle.SelectionForeColor = Color.White;

            _grid.ColumnHeadersDefaultCellStyle.BackColor = Color.FromArgb(30, 30, 45);
            _grid.ColumnHeadersDefaultCellStyle.ForeColor = Color.FromArgb(100, 200, 255);
            _grid.ColumnHeadersDefaultCellStyle.Font = new Font("Segoe UI", 9f, FontStyle.Bold);

            _grid.Columns.Add("Id", "ID");
            _grid.Columns.Add("Name", "Názov");
            _grid.Columns.Add("Width", "Šírka (mm)");
            _grid.Columns.Add("Height", "Výška (mm)");
            _grid.Columns.Add("Depth", "Dĺžka (mm)");

            _grid.Columns[0].Width = 60;  // ID column narrow

            _grid.DoubleClick += (s, e) => BtnEdit_Click(s, e);  // double-click = edit

            this.Controls.Add(_grid);

            // Search panel (add THIRD - will dock at top but below button panel)
            var pnlSearch = new Panel
            {
                Dock = DockStyle.Top,
                Height = 45,
                BackColor = Color.FromArgb(30, 30, 40),
                Padding = new Padding(10, 8, 10, 8)
            };

            var lblSearch = new Label
            {
                Text = "🔍 Hľadať:",
                ForeColor = Color.FromArgb(180, 180, 200),
                AutoSize = true,
                Location = new Point(10, 13)
            };

            _txtSearch = new TextBox
            {
                BackColor = Color.FromArgb(45, 45, 60),
                ForeColor = Color.White,
                BorderStyle = BorderStyle.FixedSingle,
                Font = new Font("Segoe UI", 10f),
                Location = new Point(95, 10),
                Width = 300
            };
            _txtSearch.TextChanged += (s, e) => ApplyFilter(_txtSearch.Text);

            pnlSearch.Controls.Add(lblSearch);
            pnlSearch.Controls.Add(_txtSearch);
            this.Controls.Add(pnlSearch);

            // Top panel with buttons (add LAST - will be at the very top)
            var pnlTop = new Panel
            {
                Dock = DockStyle.Top,
                Height = 50,
                BackColor = Color.FromArgb(25, 25, 35),
                Padding = new Padding(10, 8, 10, 8)
            };

            var flow = new FlowLayoutPanel
            {
                Dock = DockStyle.Fill,
                FlowDirection = FlowDirection.LeftToRight,
                WrapContents = false,
                AutoSize = false
            };

            _btnAdd = MakeButton("➕ Pridať nový kus", Color.FromArgb(40, 120, 60));
            _btnAdd.Click += BtnAdd_Click;

            _btnEdit = MakeButton("✏️ Upraviť vybraný", Color.FromArgb(60, 100, 160));
            _btnEdit.Click += BtnEdit_Click;

            _btnDelete = MakeButton("🗑 Zmazať vybraný", Color.FromArgb(140, 40, 40));
            _btnDelete.Click += BtnDelete_Click;

            flow.Controls.Add(_btnAdd);
            flow.Controls.Add(_btnEdit);
            flow.Controls.Add(_btnDelete);
            pnlTop.Controls.Add(flow);
            this.Controls.Add(pnlTop);
        }

        private Button MakeButton(string text, Color bg)
        {
            return new Button
            {
                Text = text,
                BackColor = bg,
                ForeColor = Color.White,
                FlatStyle = FlatStyle.Flat,
                Font = new Font("Segoe UI", 9f, FontStyle.Bold),
                Height = 34,
                Width = 160,
                Margin = new Padding(0, 0, 8, 0),
                Cursor = Cursors.Hand
            };
        }

        private void LoadData()
        {
            _grid.Rows.Clear();
            _allTemplates.Clear();
            if (_db == null) return;

            try
            {
                _allTemplates = _db.GetAll();
                ApplyFilter(_txtSearch?.Text ?? "");
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Chyba pri načítaní databázy:\n{ex.Message}", "Chyba",
                    MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void ApplyFilter(string searchText)
        {
            _grid.Rows.Clear();
            
            var filtered = string.IsNullOrWhiteSpace(searchText)
                ? _allTemplates
                : _allTemplates.Where(t => t.Name.Contains(searchText, StringComparison.OrdinalIgnoreCase)).ToList();

            foreach (var t in filtered)
                _grid.Rows.Add(t.Id, t.Name, t.Width, t.Height, t.Depth);
        }

        private void BtnAdd_Click(object sender, EventArgs e)
        {
            using (var dlg = new ItemEditDialog(null))
            {
                if (dlg.ShowDialog(this) == DialogResult.OK)
                {
                    try
                    {
                        // Check for duplicates
                        var duplicate = _db.FindDuplicate(dlg.Template);
                        if (duplicate != null)
                        {
                            string msg;
                            if (duplicate.Name.Equals(dlg.Template.Name, StringComparison.OrdinalIgnoreCase))
                                msg = $"Kus s názvom \"{duplicate.Name}\" už existuje v databáze.\n\nRozmery: {duplicate.Width}×{duplicate.Height}×{duplicate.Depth} mm";
                            else
                                msg = $"Kus s rovnakými rozmermi ({duplicate.Width}×{duplicate.Height}×{duplicate.Depth} mm) už existuje v databáze pod názvom \"{duplicate.Name}\".";
                            
                            MessageBox.Show(msg, "Duplikát", MessageBoxButtons.OK, MessageBoxIcon.Information);
                            return;
                        }
                        
                        _db.Upsert(dlg.Template);
                        LoadData();
                    }
                    catch (Exception ex)
                    {
                        MessageBox.Show($"Chyba pri ukladaní:\n{ex.Message}", "Chyba",
                            MessageBoxButtons.OK, MessageBoxIcon.Error);
                    }
                }
            }
        }

        private void BtnEdit_Click(object sender, EventArgs e)
        {
            if (_grid.SelectedRows.Count == 0)
            {
                MessageBox.Show("Vyberte kus na úpravu.", "Upozornenie",
                    MessageBoxButtons.OK, MessageBoxIcon.Information);
                return;
            }

            var row = _grid.SelectedRows[0];
            var template = new ItemTemplate
            {
                Id = Convert.ToInt32(row.Cells[0].Value),
                Name = row.Cells[1].Value?.ToString() ?? "",
                Width = Convert.ToDouble(row.Cells[2].Value),
                Height = Convert.ToDouble(row.Cells[3].Value),
                Depth = Convert.ToDouble(row.Cells[4].Value)
            };

            using (var dlg = new ItemEditDialog(template))
            {
                if (dlg.ShowDialog(this) == DialogResult.OK)
                {
                    try
                    {
                        // Check for duplicates (excluding self)
                        var duplicate = _db.FindDuplicate(dlg.Template);
                        if (duplicate != null && duplicate.Id != dlg.Template.Id)
                        {
                            string msg;
                            if (duplicate.Name.Equals(dlg.Template.Name, StringComparison.OrdinalIgnoreCase))
                                msg = $"Kus s názvom \"{duplicate.Name}\" už existuje v databáze.\n\nRozmery: {duplicate.Width}×{duplicate.Height}×{duplicate.Depth} mm";
                            else
                                msg = $"Kus s rovnakými rozmermi ({duplicate.Width}×{duplicate.Height}×{duplicate.Depth} mm) už existuje v databáze pod názvom \"{duplicate.Name}\".";
                            
                            MessageBox.Show(msg, "Duplikát", MessageBoxButtons.OK, MessageBoxIcon.Information);
                            return;
                        }
                        
                        _db.Upsert(dlg.Template);
                        LoadData();
                    }
                    catch (Exception ex)
                    {
                        MessageBox.Show($"Chyba pri ukladaní:\n{ex.Message}", "Chyba",
                            MessageBoxButtons.OK, MessageBoxIcon.Error);
                    }
                }
            }
        }

        private void BtnDelete_Click(object sender, EventArgs e)
        {
            if (_grid.SelectedRows.Count == 0)
            {
                MessageBox.Show("Vyberte kus na zmazanie.", "Upozornenie",
                    MessageBoxButtons.OK, MessageBoxIcon.Information);
                return;
            }

            var row = _grid.SelectedRows[0];
            string name = row.Cells[1].Value?.ToString() ?? "";

            var dr = MessageBox.Show(
                $"Naozaj zmazať kus \"{name}\" z databázy?\n\nTáto akcia je nevratná.",
                "Potvrdenie zmazania",
                MessageBoxButtons.YesNo,
                MessageBoxIcon.Warning);

            if (dr == DialogResult.Yes)
            {
                try
                {
                    _db.DeleteByName(name);
                    LoadData();
                }
                catch (Exception ex)
                {
                    MessageBox.Show($"Chyba pri mazaní:\n{ex.Message}", "Chyba",
                        MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
        }
    }

    /// <summary>
    /// Small dialog for adding/editing a single item template.
    /// </summary>
    internal class ItemEditDialog : Form
    {
        public ItemTemplate Template { get; private set; }

        private TextBox _txtName;
        private NumericUpDown _nudW, _nudH, _nudD;

        public ItemEditDialog(ItemTemplate existing)
        {
            Template = existing ?? new ItemTemplate();
            BuildUI();
        }

        private void BuildUI()
        {
            this.Text = Template.Id == 0 ? "Nový kus" : "Úprava kusu";
            this.Size = new Size(400, 280);
            this.StartPosition = FormStartPosition.CenterParent;
            this.FormBorderStyle = FormBorderStyle.FixedDialog;
            this.MaximizeBox = false;
            this.MinimizeBox = false;
            this.BackColor = Color.FromArgb(35, 35, 48);
            this.AutoScaleMode = AutoScaleMode.Dpi;

            var tbl = new TableLayoutPanel
            {
                Dock = DockStyle.Fill,
                ColumnCount = 2,
                RowCount = 5,
                Padding = new Padding(15)
            };
            tbl.ColumnStyles.Add(new ColumnStyle(SizeType.Absolute, 120));
            tbl.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100));
            tbl.RowStyles.Add(new RowStyle(SizeType.AutoSize));
            tbl.RowStyles.Add(new RowStyle(SizeType.AutoSize));
            tbl.RowStyles.Add(new RowStyle(SizeType.AutoSize));
            tbl.RowStyles.Add(new RowStyle(SizeType.AutoSize));
            tbl.RowStyles.Add(new RowStyle(SizeType.Percent, 100));

            tbl.Controls.Add(MakeLabel("Názov:"), 0, 0);
            _txtName = new TextBox
            {
                Text = Template.Name,
                Dock = DockStyle.Fill,
                BackColor = Color.FromArgb(45, 45, 60),
                ForeColor = Color.White,
                BorderStyle = BorderStyle.FixedSingle,
                Margin = new Padding(0, 3, 0, 8)
            };
            tbl.Controls.Add(_txtName, 1, 0);

            tbl.Controls.Add(MakeLabel("Šírka (mm):"), 0, 1);
            _nudW = MakeNUD(Template.Width);
            tbl.Controls.Add(_nudW, 1, 1);

            tbl.Controls.Add(MakeLabel("Výška (mm):"), 0, 2);
            _nudH = MakeNUD(Template.Height);
            tbl.Controls.Add(_nudH, 1, 2);

            tbl.Controls.Add(MakeLabel("Dĺžka (mm):"), 0, 3);
            _nudD = MakeNUD(Template.Depth);
            tbl.Controls.Add(_nudD, 1, 3);

            // Buttons
            var pnlButtons = new FlowLayoutPanel
            {
                Dock = DockStyle.Fill,
                FlowDirection = FlowDirection.RightToLeft,
                Margin = new Padding(0, 10, 0, 0)
            };

            var btnOk = new Button
            {
                Text = "✔ Uložiť",
                DialogResult = DialogResult.OK,
                BackColor = Color.FromArgb(40, 120, 60),
                ForeColor = Color.White,
                FlatStyle = FlatStyle.Flat,
                Font = new Font("Segoe UI", 9f, FontStyle.Bold),
                Width = 100,
                Height = 32
            };
            btnOk.Click += (s, e) =>
            {
                if (string.IsNullOrWhiteSpace(_txtName.Text))
                {
                    MessageBox.Show("Názov nemôže byť prázdny.", "Chyba", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    this.DialogResult = DialogResult.None;
                    return;
                }
                Template.Name = _txtName.Text.Trim();
                Template.Width = (double)_nudW.Value;
                Template.Height = (double)_nudH.Value;
                Template.Depth = (double)_nudD.Value;
            };

            var btnCancel = new Button
            {
                Text = "✖ Zrušiť",
                DialogResult = DialogResult.Cancel,
                BackColor = Color.FromArgb(80, 80, 100),
                ForeColor = Color.White,
                FlatStyle = FlatStyle.Flat,
                Font = new Font("Segoe UI", 9f),
                Width = 100,
                Height = 32,
                Margin = new Padding(0, 0, 8, 0)
            };

            pnlButtons.Controls.Add(btnOk);
            pnlButtons.Controls.Add(btnCancel);
            tbl.Controls.Add(pnlButtons, 0, 4);
            tbl.SetColumnSpan(pnlButtons, 2);

            this.Controls.Add(tbl);
            this.AcceptButton = btnOk;
            this.CancelButton = btnCancel;
        }

        private Label MakeLabel(string text)
        {
            return new Label
            {
                Text = text,
                ForeColor = Color.FromArgb(180, 180, 200),
                AutoSize = true,
                Anchor = AnchorStyles.Left,
                Margin = new Padding(0, 8, 8, 0)
            };
        }

        private NumericUpDown MakeNUD(double val)
        {
            return new NumericUpDown
            {
                Value = (decimal)Math.Max(1, val),
                Minimum = 1,
                Maximum = 100000,
                DecimalPlaces = 0,
                Increment = 10,
                BackColor = Color.FromArgb(45, 45, 60),
                ForeColor = Color.White,
                BorderStyle = BorderStyle.FixedSingle,
                Dock = DockStyle.Fill,
                Margin = new Padding(0, 3, 0, 8)
            };
        }
    }
}