package docker

import (
	"log"
	"path"

	"github.com/rosti-cz/node-api/apps"
)

// username in the containers under which all containers run
const appUsername = "app"
const passwordFile = "/srv/.rosti"

// Container extends App struct from App
type Container struct {
	App *apps.App `json:"app"`
}

func (c *Container) getDriver() *Driver {
	driver := &Driver{}
	return driver
}

// volumeHostPath each container has one volume mounted into it,
func (c *Container) volumeHostPath() string {
	return path.Join("/srv", c.App.Name)
}

// GetRawResourceStats returns RAW CPU and memory usage directly from Docker API
func (c *Container) GetRawResourceStats() (int64, int, error) {
	driver := c.getDriver()
	cpu, memory, err := driver.RawStats(c.App.Name)
	return cpu, memory, err
}

// GetState returns app state object with populated state fields
func (c *Container) GetState() (*apps.AppState, error) {
	status, err := c.Status()
	if err != nil {
		return nil, err
	}

	cpu, memory, err := c.ResourceUsage()
	if err != nil {
		return nil, err
	}

	bytes, inodes, err := c.DiskUsage()
	if err != nil {
		return nil, err
	}

	state := apps.AppState{
		State:           status,
		CPUUsage:        cpu,
		MemoryUsage:     memory,
		DiskUsageBytes:  bytes,
		DiskUsageInodes: inodes,
	}

	return &state, nil
}

// Status returns state of the container
// Possible values: running, stopped, no-container, unknown
func (c *Container) Status() (string, error) {
	status := "unknown"

	// if _, err := os.Stat(path.Join("/srv", c.App.Name)); !os.IsNotExist(err) {
	// 	status = "data-only"
	// }

	driver := c.getDriver()
	containerStatus, err := driver.Status(c.App.Name)
	if err != nil && err.Error() == "no container found" {
		return "no-container", nil
	}
	if err != nil {
		return status, err
	}

	status = containerStatus

	return status, nil
}

// DiskUsage returns number of bytes and inodes used by the container in it's mounted volume
func (c *Container) DiskUsage() (int, int, error) {
	return du(c.volumeHostPath())
}

// ResourceUsage returns amount of memory in B and CPU in % that the app occupies
func (c *Container) ResourceUsage() (float64, int, error) {
	driver := c.getDriver()

	cpu, memory, err := driver.Stats(c.App.Name)
	if err != nil {
		return 0.0, 0, err
	}

	return cpu, memory, nil
}

// Create creates the container
func (c *Container) Create() error {
	driver := c.getDriver()
	_, err := driver.Create(
		c.App.Name,
		c.App.Image,
		c.volumeHostPath(),
		c.App.HTTPPort,
		c.App.SSHPort,
		c.App.CPU,
		c.App.Memory,
		[]string{},
	)

	return err
}

// Start starts the container
func (c *Container) Start() error {
	driver := c.getDriver()

	return driver.Start(c.App.Name)
}

// Stop stops the container
func (c *Container) Stop() error {
	driver := c.getDriver()

	return driver.Stop(c.App.Name)
}

// Restart restarts the container
func (c *Container) Restart() error {
	driver := c.getDriver()

	err := driver.Stop(c.App.Name)
	if err != nil {
		return err
	}

	return driver.Start(c.App.Name)
}

// Destroy removes the container but keeps the data so it can be created again
func (c *Container) Destroy() error {
	driver := c.getDriver()

	return driver.Remove(c.App.Name)
}

// Delete removes both data and the container
func (c *Container) Delete() error {
	err := c.Destroy()
	if err != nil {
		return err
	}

	volumePath := path.Join("/srv", c.App.Name)
	err = removeDirectory(volumePath)
	if err != nil {
		log.Println(err)
	}

	return nil
}

// SetPassword configures password for system user app in the container
func (c *Container) SetPassword(password string) error {
	driver := c.getDriver()

	err := driver.Exec(c.App.Name, []string{"chpasswd"}, appUsername+":"+password)
	if err != nil {
		return err
	}

	err = driver.Exec(c.App.Name, []string{"tee", passwordFile}, password)
	if err != nil {
		return err
	}

	return err
}

// SetFileContent uploads text into a file inside the container. It's greate for uploading SSH keys.
// The method creates the diretory where the file is located and sets mode of the final file
func (c *Container) SetFileContent(filename string, text string, mode string) error {
	driver := c.getDriver()

	directory := path.Dir(filename)

	err := driver.Exec(c.App.Name, []string{"mkdir", "-p", directory}, "")
	if err != nil {
		return err
	}

	err = driver.Exec(c.App.Name, []string{"tee", filename}, text)
	if err != nil {
		return err
	}

	err = driver.Exec(c.App.Name, []string{"chown", directory, "app:app"}, "")
	if err != nil {
		return err
	}

	err = driver.Exec(c.App.Name, []string{"chown", filename, "app:app"}, "")
	if err != nil {
		return err
	}

	err = driver.Exec(c.App.Name, []string{"chmod", mode, filename}, "")
	return err
}