package logfile

import (
	"encoding/json"
	"fmt"
	"os"
	"sync"

	"github.com/go-flucky/flucky/pkg/internal/collect"
	"github.com/go-flucky/flucky/pkg/internal/prittyprint"

	"github.com/go-flucky/flucky/pkg/config"

	"github.com/go-flucky/flucky/pkg/types"
)

type jsonLogfile struct {
	cnf *config.Configuration
}

func (jl *jsonLogfile) Append(compression bool, measuredValues []types.MeasuredValue) error {

	allMeasuredValues, err := jl.Read()
	if err != nil {
		return err
	}

	allMeasuredValues = append(allMeasuredValues, measuredValues...)

	err = jl.Write(allMeasuredValues)
	if err != nil {
		return err

	}

	return nil
}

func (jl *jsonLogfile) Read() ([]types.MeasuredValue, error) {

	measuredValues := make([]types.MeasuredValue, 0)

	humidityValues, err := jl.readHumidities()
	if err != nil {
		return nil, err
	}
	measuredValues = append(measuredValues, humidityValues...)

	temperatureValues, err := jl.readTemperatures()
	if err != nil {
		return nil, err
	}
	measuredValues = append(measuredValues, temperatureValues...)

	return measuredValues, nil
}

func (jl *jsonLogfile) readHumidities() ([]types.MeasuredValue, error) {

	if _, err := os.Stat(jl.cnf.Device.HumidityLogfile); os.IsNotExist(err) {
		return nil, fmt.Errorf("%v: %v", errorLogfileNotFound, jl.cnf.Device.HumidityLogfile)
	}

	humidities := make([]*types.Humidity, 0)

	f, err := os.Open(jl.cnf.Device.HumidityLogfile)
	if err != nil {
		return nil, fmt.Errorf("%v: %v", errorLogfileOpen, jl.cnf.Device.HumidityLogfile)

	}
	defer f.Close()

	if err = json.NewDecoder(f).Decode(&humidities); err != nil {
		return nil, fmt.Errorf("%v: %v", errorLogfileDecode, err)
	}

	measuredValues := make([]types.MeasuredValue, 0)

	for _, humidity := range humidities {
		measuredValues = append(measuredValues, humidity)
	}

	return measuredValues, nil

}

func (jl *jsonLogfile) readTemperatures() ([]types.MeasuredValue, error) {
	if _, err := os.Stat(jl.cnf.Device.TemperatureLogfile); os.IsNotExist(err) {
		return nil, fmt.Errorf("%v: %v", errorLogfileNotFound, jl.cnf.Device.TemperatureLogfile)

	}

	temperatures := make([]*types.Temperature, 0)

	f, err := os.Open(jl.cnf.Device.TemperatureLogfile)
	if err != nil {
		return nil, fmt.Errorf("%v: %v", errorLogfileOpen, jl.cnf.Device.TemperatureLogfile)

	}
	defer f.Close()

	if err := json.NewDecoder(f).Decode(&temperatures); err != nil {
		return nil, fmt.Errorf("%v: %v", errorLogfileDecode, err)
	}

	measuredValues := make([]types.MeasuredValue, 0)

	for _, temperature := range temperatures {
		measuredValues = append(measuredValues, temperature)
	}

	return measuredValues, nil

}

func (jl *jsonLogfile) Write(measuredValues []types.MeasuredValue) error {
	humidities := make([]*types.Humidity, 0)
	temperatures := make([]*types.Temperature, 0)

	for _, measuredValue := range measuredValues {
		switch v := measuredValue.(type) {
		case *types.Humidity:
			humidities = append(humidities, v)
		case *types.Temperature:
			temperatures = append(temperatures, v)
		default:
			return fmt.Errorf("%v", errorTypeSwitch)
		}
	}

	errorChannel := make(chan error, 0)

	wg := new(sync.WaitGroup)
	wg.Add(2)

	go jl.writeHumidities(humidities, errorChannel, wg)
	go jl.writeTemperatures(temperatures, errorChannel, wg)

	wg.Wait()

	errors := collect.Errors(errorChannel)
	if len(errors) > 0 {
		return prittyprint.FormatErrors(errors)
	}

	return nil

}

func (jl *jsonLogfile) writeHumidities(humidities []*types.Humidity, errorChannel chan<- error, wg *sync.WaitGroup) {
	defer wg.Done()

	f, err := os.Create(jl.cnf.Device.HumidityLogfile)
	if err != nil {
		errorChannel <- fmt.Errorf("%v: %v", errorLogfileCreate, jl.cnf.Device.HumidityLogfile)
		return
	}
	defer f.Close()

	jsonEncoder := json.NewEncoder(f)
	jsonEncoder.SetIndent("", "  ")
	err = jsonEncoder.Encode(humidities)
	if err != nil {
		errorChannel <- fmt.Errorf("%v: %v", errorLogfileEncode, err)
		return
	}
}

func (jl *jsonLogfile) writeTemperatures(temperatures []*types.Temperature, errorChannel chan<- error, wg *sync.WaitGroup) {
	defer wg.Done()

	f, err := os.Create(jl.cnf.Device.TemperatureLogfile)
	if err != nil {
		errorChannel <- fmt.Errorf("%v: %v", errorLogfileCreate, jl.cnf.Device.TemperatureLogfile)
		return
	}
	defer f.Close()

	//writeCreationDate(temperatures)

	jsonEncoder := json.NewEncoder(f)
	jsonEncoder.SetIndent("", "  ")
	err = jsonEncoder.Encode(temperatures)
	if err != nil {
		errorChannel <- fmt.Errorf("%v: %v", errorLogfileEncode, err)
		return
	}
}