/*
Copyright 2022 The Dapr Authors
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package runfileconfig

import (
	"io"
	"os"
	"path/filepath"
	"time"

	"github.com/dapr/cli/pkg/standalone"
)

const (
	appLogFileNamePrefix   = "app"
	daprdLogFileNamePrefix = "daprd"
	logFileExtension       = ".log"
	logsDir                = "logs"
	deployDir              = "deploy"
)

// RunFileConfig represents the complete configuration options for the run file.
// It is meant to be used with - "dapr run --run-file <path-to-run-file>" command.
type RunFileConfig struct {
	Common  Common `yaml:"common"`
	Apps    []App  `yaml:"apps"`
	Version int    `yaml:"version"`
	Name    string `yaml:"name,omitempty"`
}

// ContainerConfiguration represents the application container configuration parameters.
type ContainerConfiguration struct {
	ContainerImage           string `yaml:"containerImage"`
	ContainerImagePullPolicy string `yaml:"containerImagePullPolicy"`
	CreateService            bool   `yaml:"createService"`
}

// App represents the configuration options for the apps in the run file.
type App struct {
	standalone.RunConfig   `yaml:",inline"`
	ContainerConfiguration `yaml:",inline"`
	AppDirPath             string `yaml:"appDirPath"`
	AppLogFileName         string
	DaprdLogFileName       string
	AppLogWriteCloser      io.WriteCloser
	DaprdLogWriteCloser    io.WriteCloser
}

// Common represents the configuration options for the common section in the run file.
type Common struct {
	standalone.SharedRunConfig `yaml:",inline"`
}

func (a *App) GetLogsDir() string {
	logsPath := filepath.Join(a.AppDirPath, standalone.DefaultDaprDirName, logsDir)
	os.MkdirAll(logsPath, 0o755)
	return logsPath
}

func (a *App) GetDeployDir() string {
	logsPath := filepath.Join(a.AppDirPath, standalone.DefaultDaprDirName, deployDir)
	os.MkdirAll(logsPath, 0o755)
	return logsPath
}

// CreateAppLogFile creates the log file, sets internal file handle
// and returns error if any.
func (a *App) CreateAppLogFile() error {
	var err error
	var f *os.File
	if a.AppLogDestination == standalone.Console {
		f = os.Stdout
	} else {
		f, err = a.createLogFile(appLogFileNamePrefix)
	}
	if err == nil {
		a.AppLogWriteCloser = f
		a.AppLogFileName = f.Name()
	}
	return err
}

// CreateDaprdLogFile creates the log file, sets internal file handle
// and returns error if any.
func (a *App) CreateDaprdLogFile() error {
	var err error
	var f *os.File
	if a.DaprdLogDestination == standalone.Console {
		f = os.Stdout
	} else {
		f, err = a.createLogFile(daprdLogFileNamePrefix)
	}
	if err == nil {
		a.DaprdLogWriteCloser = f
		a.DaprdLogFileName = f.Name()
	}
	return err
}

// createLogFile creates the log file and returns the file handle and error if any.
// It also adds the app ID as a prefix and the current timestamp to the file name as a suffix.
func (a *App) createLogFile(logType string) (*os.File, error) {
	logsPath := a.GetLogsDir()
	fpath := filepath.Join(logsPath, a.AppID+"_"+logType+"_"+time.Now().Format("20060102150405")+logFileExtension)
	f, err := os.Create(fpath)
	return f, err
}

func (a *App) CloseAppLogFile() error {
	if a.AppLogWriteCloser != nil {
		err := a.AppLogWriteCloser.Close()
		a.AppLogWriteCloser = nil
		return err
	}
	return nil
}

func (a *App) CloseDaprdLogFile() error {
	if a.DaprdLogWriteCloser != nil {
		err := a.DaprdLogWriteCloser.Close()
		a.DaprdLogWriteCloser = nil
		return err
	}
	return nil
}

// GetLogWriter returns the log writer based on the log destination.
func GetLogWriter(fileLogWriterCloser io.WriteCloser, logDestination standalone.LogDestType) io.Writer {
	var logWriter io.Writer
	switch logDestination {
	case standalone.Console:
		logWriter = os.Stdout
	case standalone.File:
		logWriter = fileLogWriterCloser
	case standalone.FileAndConsole:
		logWriter = io.MultiWriter(os.Stdout, fileLogWriterCloser)
	}
	return logWriter
}