package docker

import (
	"errors"
	"fmt"
	"net/http"
)

// RestartPolicy represents the policy for automatically restarting a container.
//
// Possible values are:
//
//   - always: the docker daemon will always restart the container
//   - on-failure: the docker daemon will restart the container on failures, at
//                 most MaximumRetryCount times
//   - unless-stopped: the docker daemon will always restart the container except
//                 when user has manually stopped the container
//   - no: the docker daemon will not restart the container automatically
type RestartPolicy struct {
	Name              string `json:"Name,omitempty" yaml:"Name,omitempty" toml:"Name,omitempty"`
	MaximumRetryCount int    `json:"MaximumRetryCount,omitempty" yaml:"MaximumRetryCount,omitempty" toml:"MaximumRetryCount,omitempty"`
}

// AlwaysRestart returns a restart policy that tells the Docker daemon to
// always restart the container.
func AlwaysRestart() RestartPolicy {
	return RestartPolicy{Name: "always"}
}

// RestartOnFailure returns a restart policy that tells the Docker daemon to
// restart the container on failures, trying at most maxRetry times.
func RestartOnFailure(maxRetry int) RestartPolicy {
	return RestartPolicy{Name: "on-failure", MaximumRetryCount: maxRetry}
}

// RestartUnlessStopped returns a restart policy that tells the Docker daemon to
// always restart the container except when user has manually stopped the container.
func RestartUnlessStopped() RestartPolicy {
	return RestartPolicy{Name: "unless-stopped"}
}

// NeverRestart returns a restart policy that tells the Docker daemon to never
// restart the container on failures.
func NeverRestart() RestartPolicy {
	return RestartPolicy{Name: "no"}
}

// RestartContainer stops a container, killing it after the given timeout (in
// seconds), during the stop process.
//
// See https://goo.gl/MrAKQ5 for more details.
func (c *Client) RestartContainer(id string, timeout uint) error {
	path := fmt.Sprintf("/containers/%s/restart?t=%d", id, timeout)
	resp, err := c.do(http.MethodPost, path, doOptions{})
	if err != nil {
		var e *Error
		if errors.As(err, &e) && e.Status == http.StatusNotFound {
			return &NoSuchContainer{ID: id}
		}
		return err
	}
	resp.Body.Close()
	return nil
}