using System;
using System.Data;
using System.IO;
using System.Windows.Forms;
using System.Windows.Forms.DataVisualization.Charting;
using OfficeOpenXml;


namespace WindowsFormsApp4
{
    public partial class ReportForm : Form
    {
        private DataTable currentDataTable;
        private string currentReportType = "";

        public ReportForm()
        {
            InitializeComponent();
            AttachEventHandlers();
            ConfigureChart();
        }

        private void AttachEventHandlers()
        {
            btnStatistics.Click += BtnStatistics_Click;
            btnPerformance.Click += BtnPerformance_Click;
            btnExportExcel.Click += BtnExportExcel_Click;
            btnChart.Click += BtnChart_Click;
            btnBack.Click += BtnBack_Click;
        }

        private void ConfigureChart()
        {
            chartReport.BackColor = System.Drawing.Color.FromArgb(50, 56, 67);
            chartReport.ChartAreas[0].BackColor = System.Drawing.Color.FromArgb(50, 56, 67);
            chartReport.ChartAreas[0].AxisX.LabelStyle.ForeColor = System.Drawing.Color.FromArgb(203, 232, 87);
            chartReport.ChartAreas[0].AxisY.LabelStyle.ForeColor = System.Drawing.Color.FromArgb(203, 232, 87);
            chartReport.ChartAreas[0].AxisX.MajorGrid.LineColor = System.Drawing.Color.FromArgb(198, 141, 255);
            chartReport.ChartAreas[0].AxisY.MajorGrid.LineColor = System.Drawing.Color.FromArgb(198, 141, 255);
            chartReport.Legends[0].ForeColor = System.Drawing.Color.FromArgb(203, 232, 87);
        }

        private void ConfigureGrid()
        {
            if (dgvReport.Columns.Count == 0) return;

            dgvReport.DefaultCellStyle.BackColor = System.Drawing.Color.FromArgb(50, 56, 67);
            dgvReport.DefaultCellStyle.ForeColor = System.Drawing.Color.FromArgb(203, 232, 87);
            dgvReport.DefaultCellStyle.SelectionBackColor = System.Drawing.Color.FromArgb(198, 141, 255);
            dgvReport.DefaultCellStyle.SelectionForeColor = System.Drawing.Color.FromArgb(50, 56, 67);
            dgvReport.ColumnHeadersDefaultCellStyle.BackColor = System.Drawing.Color.FromArgb(198, 141, 255);
            dgvReport.ColumnHeadersDefaultCellStyle.ForeColor = System.Drawing.Color.FromArgb(50, 56, 67);
            dgvReport.EnableHeadersVisualStyles = false;
            dgvReport.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill;
        }

        private void BtnStatistics_Click(object sender, EventArgs e)
        {
            try
            {
                currentDataTable = DatabaseHelper.GetManagerStatistics();
                dgvReport.DataSource = currentDataTable;
                ConfigureGrid();
                currentReportType = "statistics";

                tabControl1.SelectedTab = tabPageTable;
                MessageBox.Show($"Загружено {currentDataTable.Rows.Count} записей", "Информация",
                    MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Ошибка: {ex.Message}", "Ошибка",
                    MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void BtnPerformance_Click(object sender, EventArgs e)
        {
            try
            {
                DateTime startDate = dtpStartDate.Value;
                DateTime endDate = dtpEndDate.Value;

                if (startDate > endDate)
                {
                    MessageBox.Show("Начальная дата не может быть позже конечной",
                        "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    return;
                }

                currentDataTable = DatabaseHelper.GetManagerPerformance(startDate, endDate);
                dgvReport.DataSource = currentDataTable;
                ConfigureGrid();
                currentReportType = "performance";

                tabControl1.SelectedTab = tabPageTable;
                MessageBox.Show($"Отчёт за период {startDate:dd.MM.yyyy} - {endDate:dd.MM.yyyy}\nЗагружено {currentDataTable.Rows.Count} записей",
                    "Информация", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Ошибка: {ex.Message}", "Ошибка",
                    MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void BtnChart_Click(object sender, EventArgs e)
        {
            if (currentDataTable == null || currentDataTable.Rows.Count == 0)
            {
                MessageBox.Show("Сначала загрузите данные (Статистика или Эффективность)",
                    "Нет данных", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                return;
            }

            DrawChart();
            tabControl1.SelectedTab = tabPageChart;
        }

        private void DrawChart()
        {
            chartReport.Series.Clear();

            Series series = new Series();
            series.ChartType = SeriesChartType.Column;
            series.Color = System.Drawing.Color.FromArgb(198, 141, 255);
            series.BorderWidth = 2;
            series.ShadowOffset = 2;

            if (currentReportType == "statistics")
            {
                series.Name = "Выполненные заявки";

                foreach (DataRow row in currentDataTable.Rows)
                {
                    string managerName = $"{row["last_name"]} {row["first_name"]}";
                    int completed = Convert.ToInt32(row["completed_requests"]);
                    series.Points.AddXY(managerName, completed);
                }
                chartReport.Titles.Clear();
                chartReport.Titles.Add("Статистика выполнения заявок по менеджерам");
            }
            else if (currentReportType == "performance")
            {
                series.Name = "Выполнено заявок";

                foreach (DataRow row in currentDataTable.Rows)
                {
                    string managerName = $"{row["last_name"]} {row["first_name"]}";
                    int completed = Convert.ToInt32(row["completed_count"]);
                    series.Points.AddXY(managerName, completed);
                }
                chartReport.Titles.Clear();
                chartReport.Titles.Add($"Эффективность менеджеров за период");
            }

            chartReport.Series.Add(series);

            // Настройка внешнего вида графика
            chartReport.ChartAreas[0].AxisX.LabelStyle.Angle = -45;
            chartReport.ChartAreas[0].AxisX.Interval = 1;
            chartReport.ChartAreas[0].AxisX.Title = "Менеджеры";
            chartReport.ChartAreas[0].AxisY.Title = "Количество заявок";
            chartReport.ChartAreas[0].AxisX.TitleForeColor = System.Drawing.Color.FromArgb(203, 232, 87);
            chartReport.ChartAreas[0].AxisY.TitleForeColor = System.Drawing.Color.FromArgb(203, 232, 87);
        }

        private void BtnExportExcel_Click(object sender, EventArgs e)
        {
            if (currentDataTable == null || currentDataTable.Rows.Count == 0)
            {
                MessageBox.Show("Нет данных для экспорта", "Ошибка",
                    MessageBoxButtons.OK, MessageBoxIcon.Warning);
                return;
            }

            try
            {
                SaveFileDialog saveDialog = new SaveFileDialog();
                saveDialog.Filter = "Excel files (*.xlsx)|*.xlsx";
                saveDialog.FileName = $"Отчёт_{DateTime.Now:yyyyMMdd_HHmmss}.xlsx";

                if (saveDialog.ShowDialog() == DialogResult.OK)
                {
                    using (var package = new ExcelPackage())
                    {
                        var worksheet = package.Workbook.Worksheets.Add("Отчёт");

                        // Заголовки
                        for (int i = 0; i < dgvReport.Columns.Count; i++)
                        {
                            worksheet.Cells[1, i + 1].Value = dgvReport.Columns[i].HeaderText;
                            worksheet.Cells[1, i + 1].Style.Font.Bold = true;
                            worksheet.Cells[1, i + 1].Style.Fill.PatternType = OfficeOpenXml.Style.ExcelFillStyle.Solid;
                            worksheet.Cells[1, i + 1].Style.Fill.BackgroundColor.SetColor(System.Drawing.Color.FromArgb(198, 141, 255));
                        }

                        // Данные
                        for (int i = 0; i < dgvReport.Rows.Count; i++)
                        {
                            for (int j = 0; j < dgvReport.Columns.Count; j++)
                            {
                                worksheet.Cells[i + 2, j + 1].Value = dgvReport.Rows[i].Cells[j].Value?.ToString();
                            }
                        }

                        worksheet.Cells.AutoFitColumns();
                        package.SaveAs(new FileInfo(saveDialog.FileName));
                    }

                    MessageBox.Show("Отчёт успешно сохранён!", "Успешно",
                        MessageBoxButtons.OK, MessageBoxIcon.Information);
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Ошибка при экспорте: {ex.Message}", "Ошибка",
                    MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void BtnBack_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }
}