package service

import (
	"context"
	"fmt"
	"time"

	"market-data-service/api"
	"market-data-service/internal/repository"
)

// FuturesServiceImpl 期货服务实现
type FuturesServiceImpl struct {
	repo *repository.FuturesRepository
}

// NewFuturesService 创建期货服务
func NewFuturesService(repo *repository.FuturesRepository) FuturesService {
	return &FuturesServiceImpl{
		repo: repo,
	}
}

// QueryKLines 查询K线数据
func (s *FuturesServiceImpl) QueryKLines(ctx context.Context, req *api.KLineQueryRequest) (*api.KLineData, error) {
	// 解析日期
	start, err := time.Parse("20060102", req.Start)
	if err != nil {
		return nil, fmt.Errorf("invalid start date: %w", err)
	}
	end, err := time.Parse("20060102", req.End)
	if err != nil {
		return nil, fmt.Errorf("invalid end date: %w", err)
	}
	end = end.Add(24 * time.Hour).Add(-time.Second)

	// 获取K线数据
	items, err := s.repo.GetKLines(ctx, req.Symbol, req.Freq, start, end)
	if err != nil {
		return nil, err
	}

	return &api.KLineData{
		Symbol: req.Symbol,
		Freq:   req.Freq,
		Count:  len(items),
		Items:  items,
	}, nil
}

// ListSymbols 查询标的列表
func (s *FuturesServiceImpl) ListSymbols(ctx context.Context, req *api.SymbolListRequest) (*api.SymbolListData, error) {
	symbols, total, err := s.repo.ListSymbols(ctx, req)
	if err != nil {
		return nil, err
	}

	return &api.SymbolListData{
		Total: total,
		Page:  req.Page,
		Size:  req.Size,
		Items: symbols,
	}, nil
}

// BatchQueryKLines 批量查询K线
func (s *FuturesServiceImpl) BatchQueryKLines(ctx context.Context, req *api.BatchKLineRequest) (*api.BatchKLineData, error) {
	results := make([]api.BatchKLineResult, len(req.Symbols))

	for i, symbol := range req.Symbols {
		singleReq := &api.KLineQueryRequest{
			Symbol: symbol,
			Start:  req.Start,
			End:    req.End,
			Freq:   req.Freq,
		}

		data, err := s.QueryKLines(ctx, singleReq)
		results[i] = api.BatchKLineResult{
			Symbol:  symbol,
			Success: err == nil,
		}

		if err != nil {
			results[i].Error = err.Error()
		} else {
			results[i].Data = &api.KLineSubData{
				Count: data.Count,
				Items: data.Items,
			}
		}
	}

	return &api.BatchKLineData{Results: results}, nil
}

// GetTradingDates 获取交易日历
func (s *FuturesServiceImpl) GetTradingDates(ctx context.Context, req *api.TradingDatesRequest) (*api.TradingDatesData, error) {
	return s.repo.GetTradingDates(ctx, req.Start, req.End)
}

// GetContractsByUnderlying 根据品种获取合约
func (s *FuturesServiceImpl) GetContractsByUnderlying(ctx context.Context, req *api.FuturesContractsRequest) (*api.FuturesContractsData, error) {
	return s.repo.GetContractsByUnderlying(ctx, req.Underlying, req.Exchange)
}