namespace Repository;

public interface ITransactionRecordRepository : IBaseRepository<TransactionRecord>
{
    Task<TransactionRecord?> ExistsByEmailMessageIdAsync(long emailMessageId, DateTime occurredAt);

    Task<TransactionRecord?> ExistsByImportNoAsync(string importNo, string importFrom);

    /// <summary>
    /// 分页获取交易记录列表（游标分页）
    /// </summary>
    /// <param name="lastOccurredAt">上一页最后一条记录的发生时间</param>
    /// <param name="lastId">上一页最后一条记录的ID</param>
    /// <param name="pageSize">每页数量</param>
    /// <param name="searchKeyword">搜索关键词（搜索交易摘要和分类）</param>
    /// <param name="classify">筛选分类</param>
    /// <param name="type">筛选交易类型</param>
    /// <param name="year">筛选年份</param>
    /// <param name="month">筛选月份</param>
    /// <returns>交易记录列表、最后发生时间和最后ID</returns>
    Task<(List<TransactionRecord> list, DateTime? lastOccurredAt, long lastId)> GetPagedListAsync(
        DateTime? lastOccurredAt, 
        long? lastId, 
        int pageSize = 20, 
        string? searchKeyword = null,
        string? classify = null,
        TransactionType? type = null,
        int? year = null,
        int? month = null);

    /// <summary>
    /// 获取总数
    /// </summary>
    Task<long> GetTotalCountAsync();

    /// <summary>
    /// 获取所有不同的交易分类
    /// </summary>
    Task<List<string>> GetDistinctClassifyAsync();

    /// <summary>
    /// 获取指定月份每天的消费统计
    /// </summary>
    /// <param name="year">年份</param>
    /// <param name="month">月份</param>
    /// <returns>每天的消费笔数和金额</returns>
    Task<Dictionary<string, (int count, decimal amount)>> GetDailyStatisticsAsync(int year, int month);

    /// <summary>
    /// 获取指定日期范围内的交易记录
    /// </summary>
    /// <param name="startDate">开始日期</param>
    /// <param name="endDate">结束日期</param>
    /// <returns>交易记录列表</returns>
    Task<List<TransactionRecord>> GetByDateRangeAsync(DateTime startDate, DateTime endDate);

    /// <summary>
    /// 获取指定邮件的交易记录数量
    /// </summary>
    /// <param name="emailMessageId">邮件ID</param>
    /// <returns>交易记录数量</returns>
    Task<int> GetCountByEmailIdAsync(long emailMessageId);

    /// <summary>
    /// 获取月度统计数据
    /// </summary>
    /// <param name="year">年份</param>
    /// <param name="month">月份</param>
    /// <returns>月度统计数据</returns>
    Task<MonthlyStatistics> GetMonthlyStatisticsAsync(int year, int month);

    /// <summary>
    /// 获取分类统计数据
    /// </summary>
    /// <param name="year">年份</param>
    /// <param name="month">月份</param>
    /// <param name="type">交易类型（0:支出, 1:收入）</param>
    /// <returns>分类统计列表</returns>
    Task<List<CategoryStatistics>> GetCategoryStatisticsAsync(int year, int month, TransactionType type);

    /// <summary>
    /// 获取多个月的趋势统计数据
    /// </summary>
    /// <param name="startYear">开始年份</param>
    /// <param name="startMonth">开始月份</param>
    /// <param name="monthCount">月份数量</param>
    /// <returns>趋势统计列表</returns>
    Task<List<TrendStatistics>> GetTrendStatisticsAsync(int startYear, int startMonth, int monthCount);

    /// <summary>
    /// 获取指定邮件的交易记录列表
    /// </summary>
    /// <param name="emailMessageId">邮件ID</param>
    /// <returns>交易记录列表</returns>
    Task<List<TransactionRecord>> GetByEmailIdAsync(long emailMessageId);

    /// <summary>
    /// 获取未分类的账单数量
    /// </summary>
    /// <returns>未分类账单数量</returns>
    Task<int> GetUnclassifiedCountAsync();

    /// <summary>
    /// 获取未分类的账单列表
    /// </summary>
    /// <param name="pageSize">每页数量</param>
    /// <returns>未分类账单列表</returns>
    Task<List<TransactionRecord>> GetUnclassifiedAsync(int pageSize = 10);

    /// <summary>
    /// 获取按交易摘要(Reason)分组的统计信息（支持分页）
    /// </summary>
    /// <param name="pageIndex">页码，从1开始</param>
    /// <param name="pageSize">每页数量</param>
    /// <returns>分组统计列表和总数</returns>
    Task<(List<ReasonGroupDto> list, int total)> GetReasonGroupsAsync(int pageIndex = 1, int pageSize = 20);

    /// <summary>
    /// 按摘要批量更新交易记录的分类
    /// </summary>
    /// <param name="reason">交易摘要</param>
    /// <param name="type">交易类型</param>
    /// <param name="classify">分类名称</param>
    /// <returns>更新的记录数量</returns>
    Task<int> BatchUpdateByReasonAsync(string reason, TransactionType type, string classify);

    /// <summary>
    /// 根据关键词查询交易记录（模糊匹配Reason字段）
    /// </summary>
    /// <param name="keyword">关键词</param>
    /// <returns>匹配的交易记录列表</returns>
    Task<List<TransactionRecord>> QueryByWhereAsync(string sql);
    
    /// <summary>
    /// 执行完整的SQL查询
    /// </summary>
    /// <param name="completeSql">完整的SELECT SQL语句</param>
    /// <returns>查询结果列表</returns>
    Task<List<TransactionRecord>> ExecuteRawSqlAsync(string completeSql);

    /// <summary>
    /// 执行动态SQL查询，返回动态对象
    /// </summary>
    /// <param name="completeSql">完整的SELECT SQL语句</param>
    /// <returns>动态查询结果列表</returns>
    Task<List<dynamic>> ExecuteDynamicSqlAsync(string completeSql);
}

public class TransactionRecordRepository(IFreeSql freeSql) : BaseRepository<TransactionRecord>(freeSql), ITransactionRecordRepository
{
    public async Task<TransactionRecord?> ExistsByEmailMessageIdAsync(long emailMessageId, DateTime occurredAt)
    {
        return await FreeSql.Select<TransactionRecord>()
            .Where(t => t.EmailMessageId == emailMessageId && t.OccurredAt == occurredAt)
            .FirstAsync();
    }

    public async Task<TransactionRecord?> ExistsByImportNoAsync(string importNo, string importFrom)
    {
        return await FreeSql.Select<TransactionRecord>()
            .Where(t => t.ImportNo == importNo && t.ImportFrom == importFrom)
            .FirstAsync();
    }

    public async Task<(List<TransactionRecord> list, DateTime? lastOccurredAt, long lastId)> GetPagedListAsync(
        DateTime? lastOccurredAt, 
        long? lastId, 
        int pageSize = 20, 
        string? searchKeyword = null,
        string? classify = null,
        TransactionType? type = null,
        int? year = null,
        int? month = null)
    {
        var query = FreeSql.Select<TransactionRecord>();

        // 如果提供了搜索关键词，则添加搜索条件
        if (!string.IsNullOrWhiteSpace(searchKeyword))
        {
            query = query.Where(t => t.Reason.Contains(searchKeyword) ||
                                     t.Classify.Contains(searchKeyword) ||
                                     t.Card.Contains(searchKeyword) ||
                                     t.ImportFrom.Contains(searchKeyword));
        }

        // 按分类筛选
        if (!string.IsNullOrWhiteSpace(classify))
        {
            query = query.Where(t => t.Classify == classify);
        }

        // 按交易类型筛选
        if (type.HasValue)
        {
            query = query.Where(t => t.Type == type.Value);
        }

        // 按年月筛选
        if (year.HasValue && month.HasValue)
        {
            var startDate = new DateTime(year.Value, month.Value, 1);
            var endDate = startDate.AddMonths(1);
            query = query.Where(t => t.OccurredAt >= startDate && t.OccurredAt < endDate);
        }

        // 如果提供了游标，则获取小于游标位置的记录
        if (lastOccurredAt.HasValue && lastId.HasValue)
        {
            query = query.Where(t => t.OccurredAt < lastOccurredAt.Value ||
                                     (t.OccurredAt == lastOccurredAt.Value && t.Id < lastId.Value));
        }

        var list = await query
            .OrderByDescending(t => t.OccurredAt)
            .OrderByDescending(t => t.Id)
            .Page(1, pageSize)
            .ToListAsync();

        var lastRecord = list.Count > 0 ? list.Last() : null;
        return (list, lastRecord?.OccurredAt, lastRecord?.Id ?? 0);
    }

    public async Task<long> GetTotalCountAsync()
    {
        return await FreeSql.Select<TransactionRecord>().CountAsync();
    }

    public async Task<List<string>> GetDistinctClassifyAsync()
    {
        return await FreeSql.Select<TransactionRecord>()
            .Where(t => !string.IsNullOrEmpty(t.Classify))
            .Distinct()
            .ToListAsync(t => t.Classify);
    }

    public async Task<Dictionary<string, (int count, decimal amount)>> GetDailyStatisticsAsync(int year, int month)
    {
        var startDate = new DateTime(year, month, 1);
        var endDate = startDate.AddMonths(1);

        var records = await FreeSql.Select<TransactionRecord>()
            .Where(t => t.OccurredAt >= startDate && t.OccurredAt < endDate)
            .ToListAsync();

        var statistics = records
            .GroupBy(t => t.OccurredAt.ToString("yyyy-MM-dd"))
            .ToDictionary(
                g => g.Key,
                g =>
                {
                    // 分别统计收入和支出
                    var income = g.Where(t => t.Type == TransactionType.Income).Sum(t => t.Amount);
                    var expense = g.Where(t => t.Type == TransactionType.Expense).Sum(t => t.Amount);
                    // 净额 = 收入 - 支出（消费大于收入时为负数）
                    var netAmount = income - expense;
                    return (count: g.Count(), amount: netAmount);
                }
            );

        return statistics;
    }

    public async Task<List<TransactionRecord>> GetByDateRangeAsync(DateTime startDate, DateTime endDate)
    {
        return await FreeSql.Select<TransactionRecord>()
            .Where(t => t.OccurredAt >= startDate && t.OccurredAt <= endDate)
            .OrderBy(t => t.OccurredAt)
            .ToListAsync();
    }

    public async Task<int> GetCountByEmailIdAsync(long emailMessageId)
    {
        return (int)await FreeSql.Select<TransactionRecord>()
            .Where(t => t.EmailMessageId == emailMessageId)
            .CountAsync();
    }

    public async Task<List<TransactionRecord>> GetByEmailIdAsync(long emailMessageId)
    {
        return await FreeSql.Select<TransactionRecord>()
            .Where(t => t.EmailMessageId == emailMessageId)
            .OrderBy(t => t.OccurredAt)
            .ToListAsync();
    }

    public async Task<int> GetUnclassifiedCountAsync()
    {
        return (int)await FreeSql.Select<TransactionRecord>()
            .Where(t => string.IsNullOrEmpty(t.Classify))
            .CountAsync();
    }

    public async Task<List<TransactionRecord>> GetUnclassifiedAsync(int pageSize = 10)
    {
        return await FreeSql.Select<TransactionRecord>()
            .Where(t => string.IsNullOrEmpty(t.Classify))
            .OrderByDescending(t => t.OccurredAt)
            .Page(1, pageSize)
            .ToListAsync();
    }

    public async Task<(List<ReasonGroupDto> list, int total)> GetReasonGroupsAsync(int pageIndex = 1, int pageSize = 20)
    {
        // 先按照Reason分组，统计每个Reason的数量
        var groups = await FreeSql.Select<TransactionRecord>()
            .Where(t => !string.IsNullOrEmpty(t.Reason))
            .Where(t => string.IsNullOrEmpty(t.Classify)) // 只统计未分类的
            .GroupBy(t => t.Reason)
            .ToListAsync(g => new
            {
                Reason = g.Key,
                Count = g.Count()
            });

        // 按数量降序排序
        var sortedGroups = groups.OrderByDescending(g => g.Count).ToList();
        var total = sortedGroups.Count;

        // 分页
        var pagedGroups = sortedGroups
            .Skip((pageIndex - 1) * pageSize)
            .Take(pageSize)
            .ToList();

        // 为每个分组获取示例记录
        var result = new List<ReasonGroupDto>();
        foreach (var group in pagedGroups)
        {
            var sample = await FreeSql.Select<TransactionRecord>()
                .Where(t => t.Reason == group.Reason)
                .FirstAsync();

            if (sample != null)
            {
                result.Add(new ReasonGroupDto
                {
                    Reason = group.Reason,
                    Count = (int)group.Count,
                    SampleType = sample.Type,
                    SampleClassify = sample.Classify ?? string.Empty
                });
            }
        }

        return (result, total);
    }

    public async Task<int> BatchUpdateByReasonAsync(string reason, TransactionType type, string classify)
    {
        return await FreeSql.Update<TransactionRecord>()
            .Set(t => t.Type, type)
            .Set(t => t.Classify, classify)
            .Where(t => t.Reason == reason)
            .ExecuteAffrowsAsync();
    }

    public async Task<List<TransactionRecord>> QueryByWhereAsync(string sql)
    {
        return await FreeSql.Select<TransactionRecord>()
            .Where(sql)
            .OrderByDescending(t => t.OccurredAt)
            .ToListAsync();
    }
    public async Task<List<TransactionRecord>> ExecuteRawSqlAsync(string completeSql)
    {
        return await FreeSql.Ado.QueryAsync<TransactionRecord>(completeSql);
    }

    public async Task<List<dynamic>> ExecuteDynamicSqlAsync(string completeSql)
    {
        var dt = await FreeSql.Ado.ExecuteDataTableAsync(completeSql);
        var result = new List<dynamic>();
        
        foreach (System.Data.DataRow row in dt.Rows)
        {
            var expando = new System.Dynamic.ExpandoObject() as IDictionary<string, object>;
            foreach (System.Data.DataColumn column in dt.Columns)
            {
                expando[column.ColumnName] = row[column];
            }
            result.Add(expando);
        }
        
        return result;
    }
    public async Task<MonthlyStatistics> GetMonthlyStatisticsAsync(int year, int month)
    {
        var startDate = new DateTime(year, month, 1);
        var endDate = startDate.AddMonths(1);

        var records = await FreeSql.Select<TransactionRecord>()
            .Where(t => t.OccurredAt >= startDate && t.OccurredAt < endDate)
            .ToListAsync();

        var statistics = new MonthlyStatistics
        {
            Year = year,
            Month = month
        };

        foreach (var record in records)
        {
            var amount = Math.Abs(record.Amount);
            
            if (record.Type == TransactionType.Expense)
            {
                statistics.TotalExpense += amount;
                statistics.ExpenseCount++;
                if (amount > statistics.MaxExpense)
                {
                    statistics.MaxExpense = amount;
                }
            }
            else if (record.Type == TransactionType.Income)
            {
                statistics.TotalIncome += amount;
                statistics.IncomeCount++;
                if (amount > statistics.MaxIncome)
                {
                    statistics.MaxIncome = amount;
                }
            }
        }

        statistics.Balance = statistics.TotalIncome - statistics.TotalExpense;
        statistics.TotalCount = records.Count;

        return statistics;
    }

    public async Task<List<CategoryStatistics>> GetCategoryStatisticsAsync(int year, int month, TransactionType type)
    {
        var startDate = new DateTime(year, month, 1);
        var endDate = startDate.AddMonths(1);

        var records = await FreeSql.Select<TransactionRecord>()
            .Where(t => t.OccurredAt >= startDate && t.OccurredAt < endDate && t.Type == type)
            .ToListAsync();

        var categoryGroups = records
            .GroupBy(t => t.Classify ?? "未分类")
            .Select(g => new CategoryStatistics
            {
                Classify = g.Key,
                Amount = g.Sum(t => Math.Abs(t.Amount)),
                Count = g.Count()
            })
            .OrderByDescending(c => c.Amount)
            .ToList();

        // 计算百分比
        var total = categoryGroups.Sum(c => c.Amount);
        if (total > 0)
        {
            foreach (var category in categoryGroups)
            {
                category.Percent = Math.Round((category.Amount / total) * 100, 1);
            }
        }

        return categoryGroups;
    }

    public async Task<List<TrendStatistics>> GetTrendStatisticsAsync(int startYear, int startMonth, int monthCount)
    {
        var trends = new List<TrendStatistics>();

        for (int i = 0; i < monthCount; i++)
        {
            var targetYear = startYear;
            var targetMonth = startMonth + i;

            // 处理月份溢出
            while (targetMonth > 12)
            {
                targetMonth -= 12;
                targetYear++;
            }

            var startDate = new DateTime(targetYear, targetMonth, 1);
            var endDate = startDate.AddMonths(1);

            var records = await FreeSql.Select<TransactionRecord>()
                .Where(t => t.OccurredAt >= startDate && t.OccurredAt < endDate)
                .ToListAsync();

            var expense = records.Where(t => t.Type == TransactionType.Expense).Sum(t => Math.Abs(t.Amount));
            var income = records.Where(t => t.Type == TransactionType.Income).Sum(t => Math.Abs(t.Amount));

            trends.Add(new TrendStatistics
            {
                Year = targetYear,
                Month = targetMonth,
                Expense = expense,
                Income = income,
                Balance = income - expense
            });
        }

        return trends;
    }
}

/// <summary>
/// 按Reason分组统计DTO
/// </summary>
public class ReasonGroupDto
{
    /// <summary>
    /// 交易摘要
    /// </summary>
    public string Reason { get; set; } = string.Empty;

    /// <summary>
    /// 该摘要的记录数量
    /// </summary>
    public int Count { get; set; }

    /// <summary>
    /// 示例交易类型（该分组中第一条记录的类型）
    /// </summary>
    public TransactionType SampleType { get; set; }

    /// <summary>
    /// 示例分类（该分组中第一条记录的分类）
    /// </summary>
    public string SampleClassify { get; set; } = string.Empty;
}

/// <summary>
/// 月度统计数据
/// </summary>
public class MonthlyStatistics
{
    public int Year { get; set; }
    public int Month { get; set; }
    public decimal TotalExpense { get; set; }
    public decimal TotalIncome { get; set; }
    public decimal Balance { get; set; }
    public int ExpenseCount { get; set; }
    public int IncomeCount { get; set; }
    public int TotalCount { get; set; }
    public decimal MaxExpense { get; set; }
    public decimal MaxIncome { get; set; }
}

/// <summary>
/// 分类统计数据
/// </summary>
public class CategoryStatistics
{
    public string Classify { get; set; } = string.Empty;
    public decimal Amount { get; set; }
    public int Count { get; set; }
    public decimal Percent { get; set; }
}

/// <summary>
/// 趋势统计数据
/// </summary>
public class TrendStatistics
{
    public int Year { get; set; }
    public int Month { get; set; }
    public decimal Expense { get; set; }
    public decimal Income { get; set; }
    public decimal Balance { get; set; }
}