// Copyright 2024 Matthew Rich <matthewrich.conf@gmail.com>. All rights reserved.

// Container resource
package resource

import (
	"context"
	"fmt"
	"github.com/docker/docker/api/types"
	"github.com/docker/docker/api/types/image"
	"github.com/docker/docker/client"
	"gopkg.in/yaml.v3"
	_ "gopkg.in/yaml.v3"
	"log/slog"
	"net/url"
_	"os"
_	"os/exec"
	"strings"
	"encoding/json"
	"io"
	"gitea.rosskeen.house/rosskeen.house/machine"
	"decl/internal/codec"
)

type ContainerImageClient interface {
	ImagePull(ctx context.Context, refStr string, options image.PullOptions) (io.ReadCloser, error)
	ImageInspectWithRaw(ctx context.Context, imageID string) (types.ImageInspect, []byte, error)
	ImageRemove(ctx context.Context, imageID string, options image.RemoveOptions) ([]image.DeleteResponse, error)
	ImageBuild(ctx context.Context, buildContext io.Reader, options types.ImageBuildOptions) (types.ImageBuildResponse, error)
	Close() error
}

type ContainerImage struct {
	stater					machine.Stater				`yaml:"-" json:"-"`
	Id              string                `json:"id,omitempty" yaml:"id,omitempty"`
	Name            string                `json:"name" yaml:"name"`
	Created					string								`json:"created,omitempty" yaml:"created,omitempty"`
	Architecture		string								`json:"architecture,omitempty" yaml:"architecture,omitempty"`
	Variant					string								`json:"variant,omitempty" yaml:"variant,omitempty"`
	OS							string								`json:"os" yaml:"os"`
	Size						int64									`json:"size" yaml:"size"`
	Author					string								`json:"author,omitempty" yaml:"author,omitempty"`
	Comment					string								`json:"comment,omitempty" yaml:"comment,omitempty"`
	Dockerfile      string                `json:"dockerfile,omitempty" yaml:"dockerfile,omitempty"`
	ContextRef      ResourceReference     `json:"contextref,omitempty" yaml:"contextref,omitempty"`
	InjectJX        bool									`json:"injectjx,omitempty" yaml:"injectjx,omitempty"`
	State           string                `yaml:"state,omitempty" json:"state,omitempty"`

	config ConfigurationValueGetter
	apiClient ContainerImageClient
	Resources ResourceMapper               `json:"-" yaml:"-"`
}

func init() {
	ResourceTypes.Register([]string{"container-image"}, func(u *url.URL) Resource {
		c := NewContainerImage(nil)
		c.Name = ContainerImageNameFromURI(u)
		slog.Info("NewContainerImage", "container", c)
		return c
	})
}

func NewContainerImage(containerClientApi ContainerImageClient) *ContainerImage {
	var apiClient ContainerImageClient = containerClientApi
	if apiClient == nil {
		var err error
		apiClient, err = client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
		if err != nil {
			panic(err)
		}
	}
	return &ContainerImage{
		apiClient: apiClient,
		InjectJX: true,
	}
}

func (c *ContainerImage) SetResourceMapper(resources ResourceMapper) {
	c.Resources = resources
}

func (c *ContainerImage) Clone() Resource {
	return &ContainerImage {
		Id: c.Id,
		Name: c.Name,
		Created: c.Created,
		Architecture: c.Architecture,
		Variant: c.Variant,
		OS: c.OS,
		Size: c.Size,
		Author: c.Author,
		Comment: c.Comment,
		InjectJX: c.InjectJX,
		State: c.State,
		apiClient: c.apiClient,
	}
}

func (c *ContainerImage) StateMachine() machine.Stater {
	if c.stater == nil {
		c.stater = StorageMachine(c)
	}
	return c.stater
}

func URIFromContainerImageName(imageName string) string {
	var host, namespace, repo string
	elements := strings.Split(imageName, "/")
	switch len(elements) {
	case 1:
		repo = elements[0]
	case 2:
		namespace = elements[0]
		repo = elements[1]
	case 3:
		host = elements[0]
		namespace = elements[1]
		repo = elements[2]
	}
	if namespace == "" {
		return fmt.Sprintf("container-image://%s/%s", host, repo)
	}
	return fmt.Sprintf("container-image://%s/%s", host, strings.Join([]string{namespace, repo}, "/"))
}

// Reconstruct the image name from a given parsed URL
func ContainerImageNameFromURI(u *url.URL) string {
	var host string = u.Hostname()
//	var host, namespace, repo string
	elements := strings.FieldsFunc(u.RequestURI(), func(c rune) bool { return c == '/' })
	slog.Info("ContainerImageNameFromURI", "url", u, "elements", elements)
/*
	switch len(elements) {
	case 1:
		repo = elements[0]
	case 2:
		namespace = elements[0]
		repo = elements[1]
	}
*/
	if host == "" {
		return strings.Join(elements, "/")
	}
	return fmt.Sprintf("%s/%s", host, strings.Join(elements, "/"))
}

func (c *ContainerImage) URI() string {
	return URIFromContainerImageName(c.Name)
}

func (c *ContainerImage) SetURI(uri string) error {
	resourceUri, e := url.Parse(uri)
	if e == nil {
		if resourceUri.Scheme == c.Type() {
			c.Name = strings.Join([]string{resourceUri.Hostname(), resourceUri.RequestURI()}, ":")
		} else {
			e = fmt.Errorf("%w: %s is not a %s", ErrInvalidResourceURI, uri, c.Type())
		}
	}
	return e
}

func (c *ContainerImage) UseConfig(config ConfigurationValueGetter) {
	c.config = config
}

func (c *ContainerImage) JSON() ([]byte, error) {
	return json.Marshal(c)
}

func (c *ContainerImage) Validate() error {
	return fmt.Errorf("failed")
}

func (c *ContainerImage) Notify(m *machine.EventMessage) {
	slog.Info("ContainerImage.Notify()", "event", m, "state", c.State)
	ctx := context.Background()
	switch m.On {
	case machine.ENTERSTATEEVENT:
	switch m.Dest {
	case "start_read":
		if _,readErr := c.Read(ctx); readErr == nil {
			if triggerErr := c.stater.Trigger("state_read"); triggerErr == nil {
				return
			} else {
				c.State = "absent"
				panic(triggerErr)
			}
		} else {
			c.State = "absent"
			panic(readErr)
		}
	case "start_create":
		if createErr := c.Create(ctx); createErr == nil {
			if triggerErr := c.stater.Trigger("created"); triggerErr == nil {
				return
			} else {
				c.State = "absent"
				panic(triggerErr)
			}
		} else {
			c.State = "absent"
			panic(createErr)
		}
	case "start_update":
		if createErr := c.Update(ctx); createErr == nil {
			if triggerErr := c.stater.Trigger("updated"); triggerErr == nil {
				return
			} else {
				c.State = "absent"
			}
		} else {
			c.State = "absent"
			panic(createErr)
		}
	case "start_delete":
		if deleteErr := c.Delete(ctx); deleteErr == nil {
			if triggerErr := c.StateMachine().Trigger("deleted"); triggerErr == nil {
				return
			} else {
				c.State = "present"
				panic(triggerErr)
			}
		} else {
			c.State = "present"
			panic(deleteErr)
		}
	case "present", "created", "read":
		c.State = "present"
	case "absent":
		c.State = "absent"
	}
	case machine.EXITSTATEEVENT:
	}
}

func (c *ContainerImage) Apply() error {
	ctx := context.Background()
	switch c.State {
	case "absent":
		return c.Delete(ctx)
	case "present":
		return c.Create(ctx)
	}
	return nil
}

func (c *ContainerImage) Load(r io.Reader) error {
	return codec.NewYAMLDecoder(r).Decode(c)
}

func (c *ContainerImage) LoadDecl(yamlResourceDeclaration string) error {
	return codec.NewYAMLStringDecoder(yamlResourceDeclaration).Decode(c)
}

func (c *ContainerImage) Create(ctx context.Context) error {
	buildOptions := types.ImageBuildOptions{
		Dockerfile: c.Dockerfile,
		Tags:       []string{c.Name},
	}

	if c.ContextRef.Exists() {
		if c.ContextRef.ContentType() == "tar" {
			ref := c.ContextRef.Lookup(c.Resources)
			reader, readerErr := ref.ContentReaderStream()
			if readerErr != nil {
				return readerErr
			}

			buildResponse, buildErr := c.apiClient.ImageBuild(ctx, reader, buildOptions)
			if buildErr != nil {
				return buildErr
			}
			defer buildResponse.Body.Close()
			if _, outputErr := io.ReadAll(buildResponse.Body); outputErr != nil {
				return fmt.Errorf("%w %s %s", outputErr, c.Type(), c.Name)
			}
		}
	}

	return nil
}

func (c *ContainerImage) Update(ctx context.Context) error {
	return c.Create(ctx)
}

func (c *ContainerImage) Pull(ctx context.Context) error {
	out, err := c.apiClient.ImagePull(ctx, c.Name, image.PullOptions{})
	slog.Info("ContainerImage.Pull()", "name", c.Name, "error", err)
	if err == nil {
		if _, outputErr := io.ReadAll(out); outputErr != nil {
			return fmt.Errorf("%w: %s %s", outputErr, c.Type(), c.Name)
		}
	} else {
		return fmt.Errorf("%w: %s %s", err, c.Type(), c.Name)
	}
	return nil
}

func (c *ContainerImage) Inspect(ctx context.Context) (imageInspect types.ImageInspect) {
	var err error
	imageInspect, _, err = c.apiClient.ImageInspectWithRaw(ctx, c.Name)
	if err != nil {
		panic(err)
	}
	return
}

func (c *ContainerImage) Read(ctx context.Context) (resourceYaml []byte, err error) {
	defer func() {
		if r := recover(); r != nil {
			c.State = "absent"
			resourceYaml = nil
			err = fmt.Errorf("%w", r.(error))
		}
	}()

	var imageInspect types.ImageInspect
	imageInspect, _, err = c.apiClient.ImageInspectWithRaw(ctx, c.Name)
	slog.Info("ContainerImage.Read()", "name", c.Name, "error", err)
	if err != nil {
		if client.IsErrNotFound(err) {
			if pullErr := c.Pull(ctx); pullErr != nil {
				panic(pullErr)
			}
			imageInspect = c.Inspect(ctx)
		} else {
			panic(err)
		}
	}

	c.State = "present"
	c.Id = imageInspect.ID
/*
	if c.Name == "" {
		c.Name = imageInspect.Name
	}
*/
	c.Created = imageInspect.Created
	c.Author = imageInspect.Author
	c.Architecture = imageInspect.Architecture
	c.Variant = imageInspect.Variant
	c.OS = imageInspect.Os
	c.Size = imageInspect.Size
	c.Comment = imageInspect.Comment
	slog.Info("ContainerImage.Read()", "type", c.Type(), "name", c.Name, "Id", c.Id, "state", c.State, "error", err)
	return yaml.Marshal(c)
}

func (c *ContainerImage) Delete(ctx context.Context) error {
	slog.Info("ContainerImage.Delete()", "image", c)
	options := image.RemoveOptions{
		Force:         false,
		PruneChildren: false,
	}

	_, err := c.apiClient.ImageRemove(ctx, c.Id, options)
	return err
/*
for _, img := range deletedImages {
fmt.Printf("Deleted image: %s\n", img.Deleted)
fmt.Printf("Untagged image: %s\n", img.Untagged)
}
*/
}

func (c *ContainerImage) Type() string { return "container-image" }

func (c *ContainerImage) ResolveId(ctx context.Context) string {
	slog.Info("ContainerImage.ResolveId()", "name", c.Name, "machine.state", c.StateMachine().CurrentState())
	imageInspect, _, err := c.apiClient.ImageInspectWithRaw(ctx, c.Name)
	if err != nil {
		triggerResult := c.StateMachine().Trigger("notexists")
		slog.Info("ContainerImage.ResolveId()", "name", c.Name, "machine.state", c.StateMachine().CurrentState(), "resource.state", c.State, "trigger.error", triggerResult)
		panic(fmt.Errorf("%w: %s %s", err, c.Type(), c.Name))
	}
	slog.Info("ContainerImage.ResolveId()", "name", c.Name, "machine.state", c.StateMachine().CurrentState(), "resource.state", c.State)
	c.Id = imageInspect.ID
	if c.Id != "" {
		if triggerErr := c.StateMachine().Trigger("exists"); triggerErr != nil {
			panic(fmt.Errorf("%w: %s %s", triggerErr, c.Type(), c.Name))
		}
		slog.Info("ContainerImage.ResolveId() trigger created", "machine", c.StateMachine(), "state", c.StateMachine().CurrentState())
	} else {
		if triggerErr := c.StateMachine().Trigger("notexists"); triggerErr != nil {
			panic(fmt.Errorf("%w: %s %s", triggerErr, c.Type(), c.Name))
		}
		slog.Info("ContainerImage.ResolveId()", "name", c.Name, "machine.state", c.StateMachine().CurrentState(), "resource.state", c.State)
	}
	return c.Id
}