package extract

import "fmt"

// 卫星时间起点 北京时间 2000-01-01 20:00:00
var (
	ReferenceTime2000 = 946728000
)

// 焦面电箱辅助数据 128 字节 (每 16 行原始图像数据为一组)
type AuxFocalBox struct {
	TransferTime      float32 // 执行转移时间 0.5us/bit
	TrainingDone      byte    // 1B成功；0B失败
	WorkMode          byte    // 工作模式 0B正常；1B故障
	IntegralDirection byte    // 积分方向 1B正向；0B反向
	PGAGain           byte    // PGA增益
}

func (ab *AuxFocalBox) Decode(data []byte) error {
	byte0 := data[0] & 0b00111111
	ab.TransferTime = float32(uint32(byte0)<<16|uint32(data[1])<<8|uint32(data[2])) * 0.5
	ab.TrainingDone = data[3] & 0b10000000
	ab.WorkMode = data[3] & 0b01000000
	ab.IntegralDirection = data[3] & 0b00100000
	ab.PGAGain = data[3] & 0b00011111
	return nil
}

func (ab AuxFocalBox) String() string {
	return fmt.Sprintf(
		`执行转移时间：%f us\n
		TrainingDone：%x\n
		工作模式：%x\n
		积分方向：%x\n
		PGA增益：%s
		`,
		ab.TransferTime,
		ab.TrainingDone,
		ab.WorkMode,
		ab.IntegralDirection,
		ab.PGAGainValue(),
	)
}

func (ab AuxFocalBox) PGAGainValue() string {
	switch ab.PGAGain {
	case 0b0000:
		return "0.75x"
	case 0b0001:
		return "1.25x"
	case 0b0010:
		return "1.75x"
	case 0b0011:
		return "2.25x"
	case 0b0100:
		return "2.75x"
	case 0b0101:
		return "3.25x"
	case 0b0110:
		return "3.75x"
	case 0b0111:
		return "4.25x"
	case 0b1000:
		return "4.75x"
	case 0b1001:
		return "5.25x"
	case 0b1010:
		return "5.75x"
	case 0b10000:
		return "1x"
	case 0b10001:
		return "1.5x"
	case 0b10010:
		return "2x"
	case 0b10011:
		return "2.5x"
	case 0b10100:
		return "3x"
	case 0b10101:
		return "3.5x"
	case 0b10110:
		return "4x"
	case 0b10111:
		return "4.5x"
	case 0b11000:
		return "5x"
	case 0b11001:
		return "5.5x"
	case 0b11010:
		return "6x"
	default:
		return "unknown"
	}
}