using AssetManager.Data;
using AssetManager.Models.DTOs;
using SqlSugar;

namespace AssetManager.Services;

public class PortfolioService : IPortfolioService
{
    private readonly ISqlSugarClient _db;

    public PortfolioService(ISqlSugarClient db)
    {
        _db = db;
    }

    public CreatePortfolioResponse CreatePortfolio(CreatePortfolioRequest request, string userId)
    {
        var portfolio = new Portfolio
        {
            Id = "port-" + Guid.NewGuid().ToString().Substring(0, 8),
            UserId = userId,
            StrategyId = request.strategyId,
            Name = request.name,
            Currency = request.currency,
            TotalValue = (decimal)request.stocks.Sum(s => s.price * s.amount),
            ReturnRate = 0,
            Status = "运行中",
            CreatedAt = DateTime.Now,
            UpdatedAt = DateTime.Now
        };

        _db.Insertable(portfolio).ExecuteCommand();

        // 创建初始持仓
        foreach (var stock in request.stocks)
        {
            var position = new Position
            {
                Id = "pos-" + Guid.NewGuid().ToString().Substring(0, 8),
                PortfolioId = portfolio.Id,
                StockCode = stock.code,
                StockName = stock.name,
                AssetType = "Stock",
                Shares = (decimal)stock.amount,
                AvgPrice = (decimal)stock.price,
                Currency = request.currency,
                CreatedAt = DateTime.Now,
                UpdatedAt = DateTime.Now
            };

            _db.Insertable(position).ExecuteCommand();

            // 创建交易记录
            var transaction = new Transaction
            {
                Id = "trans-" + Guid.NewGuid().ToString().Substring(0, 8),
                PortfolioId = portfolio.Id,
                Type = "buy",
                StockCode = stock.code,
                AssetType = "Stock",
                Title = "初始建仓",
                Amount = (decimal)stock.amount,
                Price = (decimal)stock.price,
                TotalAmount = (decimal)(stock.price * stock.amount),
                Currency = request.currency,
                Status = "completed",
                Remark = "初始建仓",
                TransactionTime = DateTime.Now,
                CreatedAt = DateTime.Now
            };

            _db.Insertable(transaction).ExecuteCommand();
        }

        return new CreatePortfolioResponse
        {
            id = portfolio.Id,
            totalValue = (double)portfolio.TotalValue,
            returnRate = 0,
            currency = portfolio.Currency,
            createdAt = portfolio.CreatedAt.ToString("yyyy-MM-dd HH:mm:ss")
        };
    }

    public List<PortfolioListItem> GetPortfolios(string userId)
    {
        var portfolios = _db.Queryable<Portfolio>()
            .Where(p => p.UserId == userId)
            .ToList();

        return portfolios.Select(p => new PortfolioListItem
        {
            id = p.Id,
            name = p.Name,
            tags = $"{p.Status} · {p.Currency}",
            status = p.Status,
            statusType = p.Status == "运行中" ? "green" : "gray",
            iconChar = p.Name.Substring(0, 1).ToUpper(),
            iconBgClass = "bg-blue-100",
            iconTextClass = "text-blue-700",
            value = (double)p.TotalValue,
            currency = p.Currency,
            returnRate = (double)p.ReturnRate,
            returnType = p.ReturnRate >= 0 ? "positive" : "negative"
        }).ToList();
    }

    public TotalAssetsResponse GetTotalAssets(string userId)
    {
        var totalValue = _db.Queryable<Portfolio>()
            .Where(p => p.UserId == userId)
            .Sum(p => p.TotalValue);

        // 这里简化处理，实际应该计算今日盈亏和总收益率
        return new TotalAssetsResponse
        {
            totalValue = (double)totalValue,
            currency = "CNY", // 假设统一转换为CNY
            todayProfit = 0,
            todayProfitCurrency = "CNY",
            totalReturnRate = 0
        };
    }

    public PortfolioDetailResponse GetPortfolioById(string id, string userId)
    {
        var portfolio = _db.Queryable<Portfolio>()
            .Where(p => p.Id == id && p.UserId == userId)
            .First();

        if (portfolio == null)
        {
            throw new Exception("Portfolio not found or access denied");
        }

        var positions = _db.Queryable<Position>()
            .Where(pos => pos.PortfolioId == id)
            .ToList();

        return new PortfolioDetailResponse
        {
            id = portfolio.Id,
            name = portfolio.Name,
            currency = portfolio.Currency,
            strategy = new StrategyInfo
            {
                id = portfolio.StrategyId,
                name = "策略名称",
                description = "策略描述"
            },
            portfolioValue = (double)portfolio.TotalValue,
            totalReturn = (double)(portfolio.TotalValue * portfolio.ReturnRate),
            todayProfit = 0,
            todayProfitCurrency = portfolio.Currency,
            positions = positions.Select(pos => new PositionItem
            {
                id = pos.Id,
                stockCode = pos.StockCode,
                stockName = pos.StockName,
                amount = (int)pos.Shares,
                averagePrice = (double)pos.AvgPrice,
                currentPrice = (double)pos.AvgPrice,
                totalValue = (double)(pos.Shares * pos.AvgPrice),
                profit = 0,
                profitRate = 0,
                currency = pos.Currency
            }).ToList()
        };
    }

    public GetTransactionsResponse GetTransactions(string portfolioId, string userId, int limit, int offset)
    {
        // 验证投资组合是否属于该用户
        var portfolio = _db.Queryable<Portfolio>()
            .Where(p => p.Id == portfolioId && p.UserId == userId)
            .First();

        if (portfolio == null)
        {
            throw new Exception("Portfolio not found or access denied");
        }

        var transactions = _db.Queryable<Transaction>()
            .Where(t => t.PortfolioId == portfolioId)
            .OrderByDescending(t => t.TransactionTime)
            .Skip(offset)
            .Take(limit)
            .ToList();

        var total = _db.Queryable<Transaction>()
            .Where(t => t.PortfolioId == portfolioId)
            .Count();

        return new GetTransactionsResponse
        {
            items = transactions.Select(t => new TransactionItem
            {
                id = t.Id,
                portfolioId = t.PortfolioId,
                date = t.TransactionTime.ToString("yyyy-MM-dd"),
                time = t.TransactionTime.ToString("HH:mm:ss"),
                type = t.Type,
                title = t.Title,
                amount = (double)t.TotalAmount,
                currency = t.Currency,
                status = t.Status,
                remark = t.Remark
            }).ToList(),
            total = total,
            page = offset / limit + 1,
            pageSize = limit
        };
    }

    public CreateTransactionResponse CreateTransaction(CreateTransactionRequest request, string userId)
    {
        // 验证投资组合是否属于该用户
        var portfolio = _db.Queryable<Portfolio>()
            .Where(p => p.Id == request.portfolioId && p.UserId == userId)
            .First();

        if (portfolio == null)
        {
            throw new Exception("Portfolio not found or access denied");
        }

        var transaction = new Transaction
        {
            Id = "trans-" + Guid.NewGuid().ToString().Substring(0, 8),
            PortfolioId = request.portfolioId,
            Type = request.type,
            StockCode = request.stockCode,
            AssetType = "Stock",
            Title = request.remark ?? "交易",
            Amount = (decimal)request.amount,
            Price = (decimal)request.price,
            TotalAmount = (decimal)(request.price * request.amount),
            Currency = request.currency,
            Status = "processing",
            Remark = request.remark,
            TransactionTime = DateTime.Now,
            CreatedAt = DateTime.Now
        };

        _db.Insertable(transaction).ExecuteCommand();

        // 更新持仓
        var position = _db.Queryable<Position>()
            .Where(pos => pos.PortfolioId == request.portfolioId && pos.StockCode == request.stockCode)
            .First();

        if (position != null)
        {
            if (request.type == "buy")
            {
                // 计算新的平均价格
                var newTotalShares = position.Shares + (decimal)request.amount;
                var newTotalCost = (position.Shares * position.AvgPrice) + ((decimal)request.amount * (decimal)request.price);
                position.AvgPrice = newTotalCost / newTotalShares;
                position.Shares = newTotalShares;
            }
            else if (request.type == "sell")
            {
                position.Shares -= (decimal)request.amount;
                if (position.Shares <= 0)
                {
                    _db.Deleteable(position).ExecuteCommand();
                }
                else
                {
                    _db.Updateable(position).ExecuteCommand();
                }
            }
        }
        else if (request.type == "buy")
        {
            // 创建新持仓
            position = new Position
            {
                Id = "pos-" + Guid.NewGuid().ToString().Substring(0, 8),
                PortfolioId = request.portfolioId,
                StockCode = request.stockCode,
                StockName = request.remark ?? request.stockCode,
                AssetType = "Stock",
                Shares = (decimal)request.amount,
                AvgPrice = (decimal)request.price,
                Currency = request.currency,
                CreatedAt = DateTime.Now,
                UpdatedAt = DateTime.Now
            };
            _db.Insertable(position).ExecuteCommand();
        }

        // 更新投资组合总价值
        var totalValue = _db.Queryable<Position>()
            .Where(pos => pos.PortfolioId == request.portfolioId)
            .Sum(pos => pos.Shares * pos.AvgPrice);

        portfolio.TotalValue = totalValue;
        portfolio.UpdatedAt = DateTime.Now;
        _db.Updateable(portfolio).ExecuteCommand();

        return new CreateTransactionResponse
        {
            id = transaction.Id,
            totalAmount = (double)transaction.TotalAmount,
            status = transaction.Status,
            createdAt = transaction.CreatedAt.ToString("yyyy-MM-dd HH:mm:ss")
        };
    }
}