// Copyright 2013-2014 Fuzamei tech Ltd. All rights reserved.

package client

// 本文件为简化客户端的实现, 对Server服务调用进行封装

import (
	"bytes"
	"encoding/binary"
	"errors"
	"io"
	"log"
)

var ErrNoFile = errors.New("no file")

type decoder interface {
	Decode(v interface{}) error
}
type encoder interface {
	Encode(v interface{}) error
}

type DlInfo struct {
	Fname string
	Reply *HistoryReply
}

func unzip(b []byte) ([]Candle, error) {
	r := bytes.NewBuffer(b)
	return UnzipC(r)
}

func unzipTicks(b []byte) ([]Tick, error) {
	r := bytes.NewBuffer(b)
	return UnzipT(r)
}

type HistoryResponse struct {
	clientsimple *ClientSimple
	timelist     []string
	insId        string
	period       int
	n            int
	ts           int64
	db           bool
	buf          *bytes.Buffer
	fileIndex    int
	readN        int
}

func (hresp *HistoryResponse) Read(p []byte) (n int, err error) {
	n, err = hresp.buf.Read(p)
	if err == io.EOF {
		if (hresp.n < 0 && hresp.readN >= (-hresp.n)) ||
			(hresp.n > 0 && hresp.readN >= hresp.n) {
			return n, err //数据读完结束.,
		}
		fname, err := hresp.nextFile()
		if err == ErrNoFile {
			return 0, io.EOF
		}
		if err != nil {
			return 0, err
		}
		//log.Println("debug", fname, err)
		if hresp.period == TK {
			ticks, err := ReadTickFile(fname)
			if err != nil {
				return 0, err
			}
			if len(ticks) > 0 {
				if hresp.n < 0 && ticks[0].Timestamp > hresp.ts {
					return 0, nil //没有符合要求的数据,跳过这个文件
				}
				if hresp.n > 0 && ticks[len(ticks)-1].Timestamp < hresp.ts {
					return 0, nil //没有符合要求的数据,跳过这个文件
				}
			}
			if hresp.n > 0 {
				for _, tick := range ticks {
					if tick.Timestamp >= hresp.ts {
						if hresp.readN >= hresp.n {
							break
						}
						binary.Write(hresp.buf, binary.LittleEndian, &tick)
						hresp.readN++
					}
				}
			}
			if hresp.n < 0 {
				for j := len(ticks) - 1; j >= 0; j-- {
					if ticks[j].Timestamp <= hresp.ts {
						if hresp.readN >= (-hresp.n) {
							break
						}
						binary.Write(hresp.buf, binary.LittleEndian, &ticks[j])
						hresp.readN++
					}
				}
			}
		} else {
			candles, err := ReadCandleFile(fname)
			if err != nil {
				return 0, err
			}
			if len(candles) > 0 {
				if hresp.n < 0 && candles[0].Timestamp > hresp.ts {
					log.Println("debug no data", fname)
					return 0, nil //没有符合要求的数据,跳过这个文件
				}
				if hresp.n > 0 && candles[len(candles)-1].Timestamp < hresp.ts {
					log.Println("debug no data", fname)
					return 0, nil //没有符合要求的数据,跳过这个文件
				}
			}
			if hresp.n > 0 {
				for _, candle := range candles {
					if candle.Timestamp >= hresp.ts {
						if hresp.readN >= hresp.n {
							break
						}
						binary.Write(hresp.buf, binary.LittleEndian, &candle)
						hresp.readN++
					}
				}
			}
			if hresp.n < 0 {
				for j := len(candles) - 1; j >= 0; j-- {
					if candles[j].Timestamp <= hresp.ts {
						if hresp.readN >= (-hresp.n) {
							break
						}
						binary.Write(hresp.buf, binary.LittleEndian, &candles[j])
						hresp.readN++
					}
				}
			}
		}

		return hresp.buf.Read(p)
	}
	return n, err
}

func (hresp *HistoryResponse) nextFile() (string, error) {
	if hresp.n == 0 {
		return "", ErrNoFile
	}

	if hresp.n < 0 {
		for i := hresp.fileIndex; i >= 0; i-- {
			var fname string
			var err error
			fname, err = hresp.clientsimple.downloadOne(hresp.insId, hresp.timelist[i], hresp.period)
			if err == nil {
				hresp.fileIndex = i - 1
				return fname, nil
			} else {
				return "", err
			}
		}
	}

	if hresp.n > 0 {
		for i := hresp.fileIndex; i < len(hresp.timelist); i++ {
			var fname string
			var err error
			fname, err = hresp.clientsimple.downloadOne(hresp.insId, hresp.timelist[i], hresp.period)
			if err == nil {
				hresp.fileIndex = i + 1
				return fname, nil
			} else {
				return "", err
			}
		}
	}
	return "", ErrNoFile
}

func (hresp *HistoryResponse) Close() error {
	return nil
}

type HistoryResponseEx struct {
	clientsimple *ClientSimple
	timelist     []string
	insId        string
	period       int
	st           int64
	et           int64
	db           bool
	fileIndex    int
	readTime     int64
	buf          *bytes.Buffer
}

func (hresp *HistoryResponseEx) Read(p []byte) (n int, err error) {
	n, err = hresp.buf.Read(p)
	if err == io.EOF {
		if hresp.readTime >= hresp.et {
			return n, err //数据读完结束.,
		}

		fname, err := hresp.nextFile()
		if err == ErrNoFile {
			return 0, io.EOF
		}
		if err != nil {
			log.Println("debug", err)
			return 0, err
		}
		log.Println("debug", fname)
		if hresp.period == TK {
			ticks, err := ReadTickFile(fname)
			if err != nil {
				return 0, err
			}
			if len(ticks) > 0 {
				if ticks[len(ticks)-1].Timestamp < hresp.st {
					return 0, nil //没有符合要求的数据,跳过这个文件
				}
			}
			for _, tick := range ticks {
				if tick.Timestamp >= hresp.st {
					if tick.Timestamp <= hresp.et {
						binary.Write(hresp.buf, binary.LittleEndian, &tick)
						hresp.readTime = tick.Timestamp
					} else {
						break
					}
				}
			}
		} else {
			candles, err := ReadCandleFile(fname)
			if err != nil {
				return 0, err
			}
			if len(candles) > 0 {
				if candles[len(candles)-1].Timestamp < hresp.st {
					log.Println("debug no data", fname)
					return 0, nil //没有符合要求的数据,跳过这个文件
				}
			}
			for _, candle := range candles {
				if candle.Timestamp >= hresp.st {
					if candle.Timestamp <= hresp.et {
						binary.Write(hresp.buf, binary.LittleEndian, &candle)
						hresp.readTime = candle.Timestamp
					} else {
						break
					}
				}
			}
		}

		return hresp.buf.Read(p)
	}
	return n, err
}

func (hresp *HistoryResponseEx) nextFile() (string, error) {
	for i := hresp.fileIndex; i < len(hresp.timelist); i++ {
		var fname string
		var err error
		fname, err = hresp.clientsimple.downloadOne(hresp.insId, hresp.timelist[i], hresp.period)
		if err == nil {
			hresp.fileIndex = i + 1
			return fname, nil
		} else {
			return "", err
		}
	}
	return "", ErrNoFile
}

func (hresp *HistoryResponseEx) Close() error {
	return nil
}