package config

import (
	"errors"
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"path/filepath"

	retry "github.com/avast/retry-go"
	"github.com/c3os-io/c3os/internal/machine"
	yip "github.com/mudler/yip/pkg/schema"

	"gopkg.in/yaml.v2"
)

type C3OS struct {
	NetworkToken string `yaml:"network_token,omitempty"`
	Offline      bool   `yaml:"offline,omitempty"`
	Reboot       bool   `yaml:"reboot,omitempty"`
	Device       string `yaml:"device,omitempty"`
	Poweroff     bool   `yaml:"poweroff,omitempty"`
	Role         string `yaml:"role,omitempty"`
	NetworkID    string `yaml:"network_id,omitempty"`
	DNS          bool   `yaml:"dns,omitempty"`
	LogLevel     string `yaml:"loglevel,omitempty"`
}

type K3s struct {
	Env         map[string]string `yaml:"env,omitempty"`
	ReplaceEnv  bool              `yaml:"replace_env,omitempty"`
	ReplaceArgs bool              `yaml:"replace_args,omitempty"`
	Args        []string          `yaml:"args,omitempty"`
	Enabled     bool              `yaml:"enabled,omitempty"`
}

type Config struct {
	C3OS     *C3OS             `yaml:"c3os,omitempty"`
	K3sAgent K3s               `yaml:"k3s-agent,omitempty"`
	K3s      K3s               `yaml:"k3s,omitempty"`
	VPN      map[string]string `yaml:"vpn,omitempty"`
	//cloudFileContent string
	originalData map[string]interface{}
	location     string
	ConfigURL    string            `yaml:"config_url,omitempty"`
	Options      map[string]string `yaml:"options,omitempty"`
}

func (c Config) Data() map[string]interface{} {
	return c.originalData
}

func (c Config) String() string {
	if len(c.originalData) == 0 {
		dat, err := yaml.Marshal(c)
		if err == nil {
			return string(dat)
		}
	}

	dat, _ := yaml.Marshal(c.originalData)
	return string(dat)
}

func Scan(opts ...Option) (c *Config, err error) {

	o := &Options{}

	if err := o.Apply(opts...); err != nil {
		return nil, err
	}

	dir := o.ScanDir

	c = &Config{}
	files := []string{}
	for _, d := range dir {
		if f, err := listFiles(d); err == nil {
			files = append(files, f...)
		}
	}

	for _, f := range files {
		if fileSize(f) > 1.0 {
			//fmt.Println("warning: Skipping file ", f, "as exceeds 1 MB in size")
			continue
		}
		b, err := ioutil.ReadFile(f)
		if err == nil {
			yaml.Unmarshal(b, c)
			if c.C3OS != nil || c.K3s.Enabled || c.K3sAgent.Enabled {
				//	c.cloudFileContent = string(b)
				c.location = f
				yaml.Unmarshal(b, &c.originalData)
				break
			}
		}
	}

	if o.MergeBootCMDLine {
		d, err := machine.DotToYAML(o.BootCMDLineFile)
		if err == nil { // best-effort
			yaml.Unmarshal(d, c)
			// Merge back to originalData only config which are part of the config structure
			// This avoid garbage as unrelated bootargs to be merged in.
			dat, err := yaml.Marshal(c)
			if err == nil {
				yaml.Unmarshal(dat, &c.originalData)
			}
		}
	}

	if c.ConfigURL != "" {
		var body []byte

		err := retry.Do(
			func() error {
				resp, err := http.Get(c.ConfigURL)
				if err != nil {
					return err
				}
				defer resp.Body.Close()

				body, err = ioutil.ReadAll(resp.Body)
				if err != nil {
					return err
				}

				return nil
			},
		)

		if err != nil {
			return c, fmt.Errorf("could not merge configs: %w", err)
		}

		yaml.Unmarshal(body, c)
		yaml.Unmarshal(body, &c.originalData)
	}

	return c, nil
}

func fileSize(f string) float64 {
	file, err := os.Open(f)
	if err != nil {
		return 0
	}
	defer file.Close()

	stat, err := file.Stat()
	if err != nil {
		return 0
	}

	var bytes int64
	bytes = stat.Size()

	var kilobytes int64
	kilobytes = (bytes / 1024)

	var megabytes float64
	megabytes = (float64)(kilobytes / 1024) // cast to type float64
	return megabytes
}

func listFiles(dir string) ([]string, error) {
	content := []string{}

	err := filepath.Walk(dir,
		func(path string, info os.FileInfo, err error) error {
			if err != nil {
				return nil
			}
			content = append(content, path)

			return nil
		})

	return content, err
}

func ReplaceToken(dir []string, token string) (err error) {
	c, err := Scan(Directories(dir...))
	if err != nil {
		return err
	}

	if c.C3OS == nil {
		return errors.New("no config file found")
	}

	content := map[interface{}]interface{}{}

	if err := yaml.Unmarshal([]byte(c.String()), &content); err != nil {
		return err
	}

	section, exists := content["c3os"]
	if !exists {
		return errors.New("no c3os section in config file")
	}

	dd, err := yaml.Marshal(section)
	if err != nil {
		return err
	}

	piece := map[string]interface{}{}

	if err := yaml.Unmarshal(dd, &piece); err != nil {
		return err
	}

	piece["network_token"] = token
	content["c3os"] = piece

	d, err := yaml.Marshal(content)
	if err != nil {
		return err
	}

	fi, err := os.Stat(c.location)
	if err != nil {
		return err
	}

	return ioutil.WriteFile(c.location, d, fi.Mode().Perm())
}

type Stage string

const (
	NetworkStage Stage = "network"
)

func (n Stage) String() string {
	return string(n)
}

func SaveCloudConfig(name Stage, yc yip.YipConfig) error {
	dnsYAML, err := yaml.Marshal(yc)
	if err != nil {
		return err
	}
	return ioutil.WriteFile(filepath.Join("usr", "local", "cloud-config", fmt.Sprintf("100_%s.yaml", name)), dnsYAML, 0700)
}

func FromString(s string, o interface{}) error {
	return yaml.Unmarshal([]byte(s), o)
}