using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Script.Services;
using System.Web.Services;
using System.Data;
using System.Data.Common;
using System.IO;
using WebLib;
using Newtonsoft.Json;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;

namespace Education.Services
{
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    [ScriptService]
    public class 火車票價維護 : ServiceBase
    {
        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse GetVersions()
        {
            try
            {
                DAC_火車票價 dac = new DAC_火車票價();
                var versions = dac.查詢版本號List();
                return ServiceResponse.CreateSuccess("取得版本清單成功", versions);
            }
            catch (Exception ex)
            {
                return ServiceResponse.CreateError($"取得版本清單失敗：{ex.Message}");
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse GetFareTable(int versionId)
        {
            try
            {
                DAC_火車票價 dac = new DAC_火車票價();
                var data = dac.查詢票價表(versionId);

                if (data.Count == 0)
                {
                    return ServiceResponse.CreateSuccess("無資料", new
                    {
                        originStations = new List<string>(),
                        destStations = new List<string>(),
                        fares = new Dictionary<string, int>()
                    });
                }

                // 取得所有起站和訖站
                var originStations = data.OrderBy(x => x.起站站碼).Select(x => x.起站).Distinct().ToList();
                var destStations = data.OrderBy(x => x.迄站站碼).Select(x => x.迄站).Distinct().ToList();

                // 起訖站由北至南排序
                



                // 建立票價字典
                var fares = new Dictionary<string, int>();
                foreach (var item in data)
                {
                    var key = $"{item.起站}_{item.迄站}";
                    fares[key] = item.票價;
                }

                return ServiceResponse.CreateSuccess("取得票價表成功", new
                {
                    originStations = originStations,
                    destStations = destStations,
                    fares = fares
                });
            }
            catch (Exception ex)
            {
                return ServiceResponse.CreateError($"取得票價表失敗：{ex.Message}");
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse SaveFareTable(int versionId, string fares)
        {
            try
            {
                Dictionary<string, int> faresDict = JsonConvert.DeserializeObject<Dictionary<string, int>>(fares);

                using (var ts = DAC.NewTransactionScope())
                {
                    using (var conn = DAC.NewConnection())
                    {
                        DAC_火車票價 dac = new DAC_火車票價(conn);

                        // 刪除原有的版本資料
                        var existingData = dac.Select(noInputReturnAll: true, 版本號: versionId, 起站: null, 迄站: null);
                        
                        // 保存原有的生效日期（應該所有同版本的記錄生效日期都一樣）
                        DateTime effectiveDate = existingData.Count > 0 ? existingData[0].生效日期 : DateTime.Today;

                        foreach (var item in existingData)
                        {
                            dac.DeleteOne(item.編號, item.DB_APPNO);
                        }

                        // 新增更新後的資料，使用保存的生效日期
                        foreach (var kvp in faresDict)
                        {
                            var parts = kvp.Key.Split('_');
                            if (parts.Length != 2) continue;

                            var origin = parts[0];
                            var destination = parts[1];

                            if (origin == destination) continue; // 跳過同站

                            var newItem = new 火車票價Item
                            {
                                版本號 = versionId,
                                生效日期 = effectiveDate,
                                起站 = origin,
                                迄站 = destination,
                                票價 = kvp.Value
                            };

                            dac.InsertOne(newItem);
                        }

                        ts.Complete();
                    }
                }

                return ServiceResponse.CreateSuccess("儲存成功");
            }
            catch (Exception ex)
            {
                return ServiceResponse.CreateError($"儲存失敗：{ex.Message}");
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse CreateNewVersion(int versionId)
        {
            try
            {
                // 只保留年月日，不要時間
                DateTime effectiveDate = PublicVariable.TaiwanNow.Date;

                using (var ts = DAC.NewTransactionScope())
                {
                    using (var conn = DAC.NewConnection())
                    {
                        DAC_火車票價 dac = new DAC_火車票價(conn);

                        // 檢查版本是否已存在
                        var existingData = dac.Select(noInputReturnAll: true, 版本號: versionId, 起站: null, 迄站: null);
                        if (existingData.Count > 0)
                        {
                            return ServiceResponse.CreateError($"版本 {versionId} 已存在");
                        }

                        // 建立預設車站清單（使用現有最新版本的車站）
                        var latestVersion = dac.SelectAll().GroupBy(x => x.版本號).OrderByDescending(x => x.Key).FirstOrDefault();
                        if (latestVersion != null)
                        {
                            // 複製最新版本的結構（但票價為零）
                            var stations = latestVersion.Select(x => x.起站).Distinct().ToList();
                            foreach (var origin in stations)
                            {
                                foreach (var dest in stations)
                                {
                                    if (origin != dest)
                                    {
                                        var newItem = new 火車票價Item
                                        {
                                            版本號 = versionId,
                                            生效日期 = effectiveDate,
                                            起站 = origin,
                                            迄站 = dest,
                                            票價 = 0
                                        };
                                        dac.InsertOne(newItem);
                                    }
                                }
                            }
                        }

                        ts.Complete();
                    }
                }

                return ServiceResponse.CreateSuccess("新版本建立成功");
            }
            catch (Exception ex)
            {
                return ServiceResponse.CreateError($"建立新版本失敗：{ex.Message}");
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse DeleteVersion(int versionId)
        {
            try
            {
                using (var ts = DAC.NewTransactionScope())
                {
                    using (var conn = DAC.NewConnection())
                    {
                        DAC_火車票價 dac = new DAC_火車票價(conn);

                        // 刪除該版本的所有資料
                        var existingData = dac.Select(noInputReturnAll: true, 版本號: versionId, 起站: null, 迄站: null);
                        foreach (var item in existingData)
                        {
                            dac.DeleteOne(item.編號, item.DB_APPNO);
                        }

                        ts.Complete();
                    }
                }

                return ServiceResponse.CreateSuccess("版本刪除成功");
            }
            catch (Exception ex)
            {
                return ServiceResponse.CreateError($"版本刪除失敗：{ex.Message}");
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse ExportFareData(int versionId)
        {
            try
            {
                DAC_火車票價 dac = new DAC_火車票價();
                var data = dac.Select(noInputReturnAll: true, 版本號: versionId, 起站: null, 迄站: null);

                List<string> originStations;
                List<string> destStations;
                var fares = new Dictionary<string, int>();

                if (data.Count == 0)
                {
                    // 指定版本沒有資料，嘗試從其他版本取得車站清單
                    var allData = dac.SelectAll();
                    if (allData.Count == 0)
                    {
                        // 完全沒有任何資料，使用預設車站清單
                        originStations = GetDefaultOriginStations();
                        destStations = GetDefaultDestStations();
                    }
                    else
                    {
                        // 使用現有版本的車站清單（會包含所有現有版本出現過的車站）
                        originStations = allData.Select(x => x.起站).Distinct().ToList();
                        destStations = allData.Select(x => x.迄站).Distinct().ToList();
                    }
                }
                else
                {
                    // 取得該版本的起站和訖站
                    originStations = data.Select(x => x.起站).Distinct().ToList();
                    destStations = data.Select(x => x.迄站).Distinct().ToList();

                    // 建立票價字典
                    foreach (var item in data)
                    {
                        var key = $"{item.起站}_{item.迄站}";
                        fares[key] = item.票價;
                    }
                }

                // 建立 Excel 檔案
                var excelData = CreateFareExcel(originStations, destStations, fares, versionId);

                var response = new 
                {
                    Data = new
                    {
                        originStations = originStations,
                        destStations = destStations,
                        fares = fares
                    },
                    ExcelData = excelData,
                    Success = true,
                    Message = "匯出成功"
                };

                return ServiceResponse.CreateSuccess("匯出成功", response);
            }
            catch (Exception ex)
            {
                return ServiceResponse.CreateError($"匯出失敗：{ex.Message}");
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse GetExcelTemplate()
        {
            try
            {
                // 建立預設車站清單
                var originStations = GetDefaultOriginStations();
                var destStations = GetDefaultDestStations();

                // 建立空的 Excel 範本
                var excelData = CreateFareExcel(originStations, destStations, new Dictionary<string, int>(), 0, isTemplate: true);

                return ServiceResponse.CreateSuccess("取得範本成功", excelData);
            }
            catch (Exception ex)
            {
                return ServiceResponse.CreateError($"取得範本失敗：{ex.Message}");
            }
        }

        private List<string> GetDefaultOriginStations()
        {
            return new List<string>
            {
                "台北", "桃園", "中壢", "埔心", "楊梅", "竹北", "新竹", "竹南", "苗栗", 
                "花蓮", "豐原", "清水", "台中"
            };
        }

        private List<string> GetDefaultDestStations()
        {
            return new List<string>
            {
                "基隆", "八堵", "七堵", "汐止", "南港", "松山", "台北", "板橋", "樹林", 
                "鶯歌", "桃園", "中壢", "楊梅", "竹北", "新竹", "竹東", "竹南", "苗栗", 
                "豐原", "大甲", "清水", "台中", "沙鹿", "彰化", "員林", "田中", "二水", 
                "斗六", "斗南", "嘉義", "新營", "善化", "台南", "岡山", "高雄", "屏東"
            };
        }

        private string CreateFareExcel(List<string> originStations, List<string> destStations, 
            Dictionary<string, int> fares, int versionId, bool isTemplate = false)
        {
            XSSFWorkbook workbook = new XSSFWorkbook();
            try
            {
                var sheet = workbook.CreateSheet("火車票價");
                
                // 設定列寬
                sheet.SetColumnWidth(0, 3500);
                for (int i = 1; i <= originStations.Count; i++)
                {
                    sheet.SetColumnWidth(i, 2500);
                }

                // 設定標題列（橫軸為起站）
                var headerRow = sheet.CreateRow(0);
                headerRow.CreateCell(0).SetCellValue("訖站\\起站");
                for (int i = 0; i < originStations.Count; i++)
                {
                    headerRow.CreateCell(i + 1).SetCellValue(originStations[i]);
                }

                // 設定資料列（縱軸為訖站）
                for (int i = 0; i < destStations.Count; i++)
                {
                    var row = sheet.CreateRow(i + 1);
                    row.CreateCell(0).SetCellValue(destStations[i]);

                    for (int j = 0; j < originStations.Count; j++)
                    {
                        var cell = row.CreateCell(j + 1);
                        
                        if (originStations[j] == destStations[i])
                        {
                            // 同站，不填票價
                            cell.SetCellValue("");
                        }
                        else
                        {
                            var key = $"{originStations[j]}_{destStations[i]}";
                            if (fares.ContainsKey(key))
                            {
                                cell.SetCellValue(fares[key]);
                            }
                            else if (!isTemplate)
                            {
                                cell.SetCellValue("");
                            }
                        }
                    }
                }

                // 轉換為 Base64
                using (var ms = new MemoryStream())
                {
                    workbook.Write(ms);
                    return Convert.ToBase64String(ms.ToArray());
                }
            }
            finally
            {
                workbook.Close();
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse ImportFareData(string filePath)
        {
            try
            {
                // 驗證檔案路徑
                if (string.IsNullOrEmpty(filePath) || !File.Exists(filePath))
                {
                    return ServiceResponse.CreateError("檔案不存在或已過期");
                }

                // 在迴圈外取得當前日期，只保留年月日
                DateTime effectiveDate = PublicVariable.TaiwanNow.Date;

                // 從檔案讀取並驗證資料
                var fares = new Dictionary<string, int>();
                var originStations = new List<string>();
                var destStations = new List<string>();

                using (var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                {
                    IWorkbook workbook = null;

                    try
                    {
                        fileStream.Position = 0;
                        workbook = new XSSFWorkbook(fileStream);
                    }
                    catch
                    {
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("檔案格式錯誤");
                    }

                    if (workbook == null || workbook.NumberOfSheets == 0)
                    {
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("Excel 檔案格式錯誤");
                    }

                    var sheet = workbook.GetSheetAt(0);
                    if (sheet == null || sheet.PhysicalNumberOfRows == 0)
                    {
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("Excel 工作表為空");
                    }

                    // 讀取標題列
                    var headerRow = sheet.GetRow(0);
                    if (headerRow == null)
                    {
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("Excel 缺少標題列");
                    }

                    // 取得起站列表（橫軸為起站，從第二欄開始）
                    for (int i = 1; i < headerRow.PhysicalNumberOfCells; i++)
                    {
                        var cell = headerRow.GetCell(i);
                        if (cell != null && !string.IsNullOrEmpty(cell.StringCellValue))
                        {
                            originStations.Add(cell.StringCellValue);
                        }
                    }

                    // 讀取資料列（縱軸為訖站，第一欄為訖站）
                    for (int rowIdx = 1; rowIdx <= sheet.LastRowNum; rowIdx++)
                    {
                        var row = sheet.GetRow(rowIdx);
                        if (row == null) continue;

                        // 第一欄是訖站
                        var destCell = row.GetCell(0);
                        if (destCell == null || string.IsNullOrEmpty(destCell.StringCellValue))
                            continue;

                        string dest = destCell.StringCellValue;
                        destStations.Add(dest);

                        // 從第二欄開始是票價，對應起站（橫軸）
                        for (int colIdx = 1; colIdx <= originStations.Count; colIdx++)
                        {
                            var fareCell = row.GetCell(colIdx);
                            string origin = originStations[colIdx - 1];

                            if (origin == dest)
                                continue; // 跳過同站

                            if (fareCell != null && fareCell.CellType != CellType.Blank)
                            {
                                try
                                {
                                    int fare = (int)fareCell.NumericCellValue;
                                    if (fare >= 0)
                                    {
                                        var key = $"{origin}_{dest}";
                                        fares[key] = fare;
                                    }
                                }
                                catch
                                {
                                    // 忽略格式錯誤的單元格
                                }
                            }
                        }
                    }
                }

                // 執行匯入 - 只有新增模式，自動產生新版本號
                using (var ts = DAC.NewTransactionScope())
                {
                    using (var conn = DAC.NewConnection())
                    {
                        DAC_火車票價 dac = new DAC_火車票價(conn);

                        // 取得下一個版本號
                        int targetVersionId = 1;
                        var allVersions = dac.SelectAll();
                        if (allVersions.Count > 0)
                        {
                            targetVersionId = allVersions.Max(x => x.版本號) + 1;
                        }

                        // 新增資料（使用迴圈外取得的 effectiveDate，只保留年月日）
                        foreach (var kvp in fares)
                        {
                            var parts = kvp.Key.Split('_');
                            if (parts.Length != 2) continue;

                            var origin = parts[0];
                            var destination = parts[1];

                            if (origin == destination) continue; // 跳過同站

                            var newItem = new 火車票價Item
                            {
                                版本號 = targetVersionId,
                                生效日期 = effectiveDate,  // 使用迴圈外的年月日
                                起站 = origin,
                                迄站 = destination,
                                票價 = kvp.Value
                            };

                            dac.InsertOne(newItem);
                        }

                        ts.Complete();
                    }
                }

                // 匯入成功後刪除上傳的臨時檔案
                DeleteUploadedFile(filePath);

                return ServiceResponse.CreateSuccess("匯入成功");
            }
            catch (Exception ex)
            {
                // 匯入失敗也刪除上傳的檔案
                if (!string.IsNullOrEmpty(filePath))
                {
                    DeleteUploadedFile(filePath);
                }
                return ServiceResponse.CreateError($"匯入失敗：{ex.Message}");
            }
        }

        [WebMethod(EnableSession = true)]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public ServiceResponse ValidateImportFile(string filePath)
        {
            try
            {
                if (string.IsNullOrEmpty(filePath) || !File.Exists(filePath))
                {
                    return ServiceResponse.CreateError("檔案不存在");
                }

                var fares = new Dictionary<string, int>();
                var originStations = new List<string>();
                var destStations = new List<string>();
                var errors = new List<string>();
                int rowCount = 0;

                using (var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                {
                    IWorkbook workbook = null;
                    
                    // 嘗試讀取為 XLSX
                    try
                    {
                        fileStream.Position = 0;
                        workbook = new XSSFWorkbook(fileStream);
                    }
                    catch
                    {
                        // 檔案格式錯誤，刪除上傳的檔案
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("只支援 .xlsx 格式的 Excel 檔案");
                    }

                    if (workbook == null || workbook.NumberOfSheets == 0)
                    {
                        // 檔案格式錯誤，刪除上傳的檔案
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("Excel 檔案格式錯誤");
                    }

                    var sheet = workbook.GetSheetAt(0);
                    if (sheet == null || sheet.PhysicalNumberOfRows == 0)
                    {
                        // 工作表為空，刪除上傳的檔案
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("Excel 工作表為空");
                    }

                    // 讀取標題列
                    var headerRow = sheet.GetRow(0);
                    if (headerRow == null)
                    {
                        // 標題列缺失，刪除上傳的檔案
                        DeleteUploadedFile(filePath);
                        return ServiceResponse.CreateError("Excel 缺少標題列");
                    }

                    // 取得起站列表（橫軸為起站，從第二欄開始）
                    for (int i = 1; i < headerRow.PhysicalNumberOfCells; i++)
                    {
                        var cell = headerRow.GetCell(i);
                        if (cell != null && !string.IsNullOrEmpty(cell.StringCellValue))
                        {
                            originStations.Add(cell.StringCellValue);
                        }
                    }

                    // 讀取資料列（縱軸為訖站，第一欄為訖站）
                    for (int rowIdx = 1; rowIdx <= sheet.LastRowNum; rowIdx++)
                    {
                        var row = sheet.GetRow(rowIdx);
                        if (row == null) continue;

                        // 第一欄是訖站
                        var destCell = row.GetCell(0);
                        if (destCell == null || string.IsNullOrEmpty(destCell.StringCellValue))
                            continue;

                        string dest = destCell.StringCellValue;
                        destStations.Add(dest);

                        // 從第二欄開始是票價，對應起站（橫軸）
                        for (int colIdx = 1; colIdx <= originStations.Count; colIdx++)
                        {
                            var fareCell = row.GetCell(colIdx);
                            string origin = originStations[colIdx - 1];

                            if (origin == dest)
                                continue; // 跳過同站

                            if (fareCell != null && fareCell.CellType != CellType.Blank)
                            {
                                try
                                {
                                    int fare = (int)fareCell.NumericCellValue;
                                    if (fare < 0)
                                    {
                                        errors.Add($"第 {rowIdx + 1} 列，{origin} 到 {dest} 的票價不能為負數");
                                    }
                                    else
                                    {
                                        var key = $"{origin}_{dest}";
                                        fares[key] = fare;
                                    }
                                }
                                catch
                                {
                                    errors.Add($"第 {rowIdx + 1} 列，{origin} 到 {dest} 的票價格式不正確");
                                }
                            }
                        }

                        rowCount++;
                    }
                }

                if (errors.Count > 0)
                {
                    // 驗證失敗，刪除上傳的檔案
                    DeleteUploadedFile(filePath);
                    return ServiceResponse.CreateSuccess("檔案驗證失敗", new
                    {
                        Errors = errors,
                        RowCount = 0
                    });
                }

                return ServiceResponse.CreateSuccess("檔案驗證成功", new
                {
                    Fares = fares,
                    OriginStations = originStations.Distinct().ToList(),
                    DestStations = destStations.Distinct().ToList(),
                    Errors = new List<string>()
                });
            }
            catch (Exception ex)
            {
                // 驗證異常，刪除上傳的檔案
                if (!string.IsNullOrEmpty(filePath))
                {
                    DeleteUploadedFile(filePath);
                }
                return ServiceResponse.CreateError($"驗證檔案失敗：{ex.Message}");
            }
        }

        private void DeleteUploadedFile(string filePath)
        {
            if (string.IsNullOrEmpty(filePath))
            {
                return;
            }

            try
            {
                // 刪除指定的檔案
                if (File.Exists(filePath))
                {
                    File.Delete(filePath);
                }

                // 清理所有 TrainFareImport_*.xlsx 格式的檔案
                string uploadDir = Path.Combine(HttpContext.Current.Server.MapPath("~/"), "DocUpload");
                if (Directory.Exists(uploadDir))
                {
                    try
                    {
                        var searchPattern = "TrainFareImport_*.xlsx";
                        var oldFiles = Directory.GetFiles(uploadDir, searchPattern);
                        
                        foreach (var oldFile in oldFiles)
                        {
                            try
                            {
                                // 刪除30分鐘以前的檔案
                                var fileInfo = new FileInfo(oldFile);
                                if (DateTime.Now - fileInfo.LastWriteTime > TimeSpan.FromMinutes(30))
                                {
                                    File.Delete(oldFile);
                                }
                            }
                            catch (Exception ex)
                            {
                                System.Diagnostics.Debug.WriteLine($"清理舊檔案失敗：{oldFile} - {ex.Message}");
                            }
                        }
                    }
                    catch (Exception ex)
                    {
                        System.Diagnostics.Debug.WriteLine($"掃描清理檔案失敗：{ex.Message}");
                    }
                }
            }
            catch (Exception ex)
            {
                // 記錄刪除失敗但不拋出例外
                System.Diagnostics.Debug.WriteLine($"刪除上傳檔案失敗：{filePath} - {ex.Message}");
            }
        }
    }
}