package stacks

import (
	"context"
	_ "embed"
	"fmt"
	"os"
	"path/filepath"

	"github.com/pulumi/pulumi/sdk/v3/go/auto"
	"github.com/pulumi/pulumi/sdk/v3/go/auto/optdestroy"
	"github.com/pulumi/pulumi/sdk/v3/go/auto/optpreview"
	"github.com/pulumi/pulumi/sdk/v3/go/auto/optup"
	"github.com/pulumi/pulumi/sdk/v3/go/pulumi"
	"gitlab.com/dananglin/helix/internal/config"
	"gitlab.com/dananglin/helix/internal/docker"
)

// ContainerStack is a stack for managing the containers
// for the forge platform.
type ContainerStack struct {
	Name  string
	Stack auto.Stack
}

//go:embed templates/traefik/Dockerfile.tmpl
var templateTraefikDockerfile string

//go:embed templates/traefik/traefik.yaml.tmpl
var templateTraefikStaticConfig string

// newContainerStack creates the ContainerStack value.
func newContainerStack(ctx context.Context, project, stack, dockerNetwork string, conf config.TraefikConfig) (*ContainerStack, error) {
	deployFunc := deployContainerStack(project, dockerNetwork, conf)

	s, err := createOrSelectStack(ctx, project, stack, deployFunc)
	if err != nil {
		return nil, fmt.Errorf("unable to initialise the '%s' stack...\n%w", stack, err)
	}

	c := ContainerStack{
		Name:  stack,
		Stack: s,
	}

	return &c, nil
}

// Preview the proposed changes to the container stack.
func (c *ContainerStack) Preview(ctx context.Context) error {
	streamer := optpreview.ProgressStreams(os.Stdout)
	_, err := c.Stack.Preview(ctx, streamer)
	if err != nil {
		return fmt.Errorf("unable to preview the '%s' stack...\n%w", c.Name, err)
	}
	return nil
}

// Update the container stack.
func (c *ContainerStack) Update(ctx context.Context) error {
	streamer := optup.ProgressStreams(os.Stdout)
	_, err := c.Stack.Up(ctx, streamer)
	if err != nil {
		return fmt.Errorf("unable to update '%s' stack...\n%w", c.Name, err)
	}
	return nil
}

// Destroy the container stack.
func (c *ContainerStack) Destroy(ctx context.Context) error {
	streamer := optdestroy.ProgressStreams(os.Stdout)
	_, err := c.Stack.Destroy(ctx, streamer)
	if err != nil {
		return fmt.Errorf("unable to destroy '%s' stack...\n%w", c.Name, err)
	}
	return nil
}

// deployContainerStack returns a Pulumi run function
// that is used to deploy the container stack.
func deployContainerStack(project, dockerNetwork string, t config.TraefikConfig) pulumi.RunFunc {
	return func(ctx *pulumi.Context) error {
		base_cache, err := os.UserCacheDir()
		if err != nil {
			return fmt.Errorf("unable to get the base cache directory...\n%w", err)
		}

		traefikContextDir := filepath.Join(base_cache, "helix", project, "traefik")

		if err := os.MkdirAll(traefikContextDir, 0700); err != nil {
			return fmt.Errorf("unable to make the cache directory for traefik...\n%w", err)
		}

		if err := generateFile(t, templateTraefikDockerfile, "traefikDocker", filepath.Join(traefikContextDir, "Dockerfile")); err != nil {
			return fmt.Errorf("unable to generate the Traefik Dockerfile from template...\n%w", err)
		}

		if err := generateFile(t, templateTraefikStaticConfig, "traefikStaticConf", filepath.Join(traefikContextDir, "traefik.yml")); err != nil {
			return fmt.Errorf("unable to generate the Traefik static configuration from template...\n%w", err)
		}

		c := docker.DockerImageInput{
			BuildContext: pulumi.String(traefikContextDir),
			Dockerfile:   pulumi.String(filepath.Join(traefikContextDir, "Dockerfile")),
			ImageName:    pulumi.String("helix-traefik"),
			ImageTag:     pulumi.String(t.Version),
			UniqueLabel:  "traefik-image",
		}

		traefikImage, err := docker.CreateDockerImage(ctx, c)
		if err != nil {
			return err
		}

		traefikContainerInput := docker.DockerContainerInput{
			Image:       traefikImage.ImageName,
			Ipv4Address: pulumi.String(t.ContainerIp),
			Name:        pulumi.String("helix-traefik"),
			Network:     pulumi.String(dockerNetwork),
			UniqueLabel: "traefik-container",
		}

		if err = docker.CreateDockerContainer(ctx, traefikContainerInput); err != nil {
			return err
		}

		return nil
	}
}