package pipeline_executor

import (
	"bytes"
	"context"
	"fmt"
	"os"
	"path/filepath"
	"strings"

	"github.com/jhoonb/archivex"

	"github.com/docker/docker/api/types"
	"github.com/docker/docker/api/types/container"
	"github.com/docker/docker/api/types/mount"
	"github.com/docker/docker/client"
	"github.com/docker/docker/pkg/stdcopy"
	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/plumbing/transport"
	"github.com/go-git/go-git/v5/plumbing/transport/http"
	"github.com/go-git/go-git/v5/plumbing/transport/ssh"
	"github.com/op/go-logging"

	"git.ohea.xyz/cursorius/server/config"
	"git.ohea.xyz/cursorius/server/database"
)

var log = logging.MustGetLogger("cursorius-server")

type PipelineExecution struct {
	Pipeline database.Pipeline
	Ref      string
	Run      database.Run
}

func ExecutePipeline(pe PipelineExecution, db database.Database, pipelineConf config.PipelineConf) {
	idStr := pe.Pipeline.Id.String()

	jobFolder := filepath.Join(pipelineConf.WorkingDir, pe.Pipeline.Id.String(), pe.Run.Id.String())
	cloneFolder := filepath.Join(jobFolder, "repo")

	log.Debugf("%v: URL: %v", idStr, pe.Pipeline.Url)
	log.Debugf("%v: Folder: %v", idStr, jobFolder)

	err := os.RemoveAll(jobFolder)
	if err != nil {
		log.Errorf("%v: could not delete existing folder %v", idStr, jobFolder)
		return
	}

	err = os.MkdirAll(cloneFolder, 0755)
	if err != nil {
		log.Errorf("%v: could not create working directory: %w", idStr, pe.Pipeline.Name, err)
		return
	}

	log.Infof("%v: cloning source from URL %v", idStr, pe.Pipeline.Url)

	var auth transport.AuthMethod

	if pe.Pipeline.CloneCredential != nil {
		credential, err := db.GetCloneCredentialById(*pe.Pipeline.CloneCredential)
		if err != nil {
			log.Errorf("%v: could not get credenital from db: %v", idStr, err)
			return
		}

		switch credential.Type {
		case "USER_PASS":
			log.Debugf("%v: credential %v configured", idStr, credential.Name)
			auth = transport.AuthMethod(&http.BasicAuth{
				Username: credential.Username,
				Password: credential.Secret,
			})
		case "SSH_KEY":
			publicKeys, err := ssh.NewPublicKeys(credential.Username, []byte(credential.Secret), "")
			if err != nil {
				log.Errorf("%v: could not parse credential %v: %v", idStr, credential.Name, err)
				return
			}
			auth = transport.AuthMethod(publicKeys)
		default:
			log.Errorf("%v: unsupported credential type %v", idStr, credential.Type)
			return
		}
	} else {
		auth = nil
	}

	_, err = git.PlainClone(cloneFolder, false, &git.CloneOptions{
		URL:  pe.Pipeline.Url,
		Auth: auth,
	})
	if err != nil {
		log.Errorf("%v: could not clone repo: %v", idStr, err)
		return
	}

	cli, err := client.NewClientWithOpts(client.FromEnv)
	if err != nil {
		log.Errorf("%v: could not create docker client: %w", idStr, err)
		return
	}
	log.Infof("%v: source cloned successfully", idStr)

	ctx := context.Background()

	log.Debugf("%v: tarring up job source", idStr)

	log.Debugf("%v: creating tarfile", idStr)
	tarFile := filepath.Join(jobFolder, "archive.tar")
	tar := new(archivex.TarFile)
	err = tar.Create(tarFile)
	if err != nil {
		log.Errorf("%v: could not create tarfile: %w", idStr, err)
		return
	}

	log.Debugf("%v: adding files to tarfile", idStr)
	err = tar.AddAll(cloneFolder, false)
	if err != nil {
		log.Errorf("%v: could not add repo to tarfile: %w", idStr, err)
		return
	}

	log.Debugf("%v: saving tarfile tarfile", idStr)
	err = tar.Close()
	if err != nil {
		log.Errorf("%v: could not close tarfile: %w", idStr, err)
		return
	}
	log.Debugf("%v: job source tarred", idStr)

	log.Infof("%v: building container", idStr)

	dockerBuildContext, err := os.Open(tarFile)
	defer dockerBuildContext.Close()

	imageName := fmt.Sprintf("%v-%v:latest", pe.Pipeline.Id.String(), pe.Run.Id.String())

	buildResponse, err := cli.ImageBuild(context.Background(), dockerBuildContext, types.ImageBuildOptions{
		Tags:       []string{imageName},
		Dockerfile: ".cursorius/Dockerfile",
	})
	if err != nil {
		log.Errorf("%v: could not build container: %w", idStr, err)
		return
	}

	log.Debugf("%v: reading build output from docker daemon", idStr)

	err = db.UpdateRunBuildOutput(pe.Run.Id, cleanupBuildOutput(buildResponse.Body))
	if err != nil {
		log.Errorf("%v: could not update build output for run: %w", idStr, err)
		return
	}

	log.Debugf("%v: build output read from docker daemon", idStr)

	err = buildResponse.Body.Close()
	if err != nil {
		log.Errorf("%v: could not close build response body: %w", idStr, err)
		return
	}

	log.Debugf("%v: build response closed", idStr)

	log.Infof("%v: image built sucessfully", idStr)

	hostConfig := container.HostConfig{}

	if pipelineConf.DockerNetwork != nil {
		hostConfig.NetworkMode = container.NetworkMode(*pipelineConf.DockerNetwork)
	}

	if pipelineConf.MountConf.Type == config.Bind {
		sourceDir := filepath.Join(pipelineConf.MountConf.Source, pe.Pipeline.Id.String(), pe.Run.Id.String())

		hostConfig.Mounts = append(hostConfig.Mounts,
			mount.Mount{
				Type:        mount.TypeBind,
				Source:      sourceDir,
				Target:      "/cursorius/src",
				ReadOnly:    false,
				Consistency: mount.ConsistencyDefault,
			},
		)
	} else if pipelineConf.MountConf.Type == config.Volume {
		hostConfig.Mounts = append(hostConfig.Mounts,
			mount.Mount{
				Type:        mount.TypeVolume,
				Source:      pipelineConf.MountConf.Source,
				Target:      "/cursorius/src",
				ReadOnly:    false,
				Consistency: mount.ConsistencyDefault,
			},
		)
	}

	env := make([]string, 0)

	// set cursorius environment variables
	env = append(env, []string{
		fmt.Sprintf("CURSORIUS_RUN_ID=%v", pe.Run.Id),
		"CURSORIUS_SRC_DIR=/cursorius/src",
		fmt.Sprintf("CURSORIUS_SERVER_URL=%v", pipelineConf.AccessURL),
	}...)

	// load secrets into environment
	secrets, err := db.GetSecretsForPipeline(pe.Pipeline.Id)
	if err != nil {
		log.Errorf("%v: could not get secrets for pipeline", idStr, err)
		return
	}

	for _, secret := range secrets {
		// the env name is validated to be just uppercase letters, numbers, and underscores on ingestion
		env = append(env, fmt.Sprintf("%v=%v", strings.ToUpper(secret.Name), secret.Secret))
	}

	log.Debugf("%v: creating container", idStr)

	resp, err := cli.ContainerCreate(ctx,
		&container.Config{
			Image: imageName,
			Tty:   false,
			Env:   env,
		},
		// TODO: fix running the runner in docker (add VolumesFrom to HostConfig)
		&hostConfig,
		nil, nil, "",
	)
	if err != nil {
		log.Errorf("%v: could not create container: %w", idStr, err)
		return
	}

	log.Info("%v: starting container", idStr)

	if err := cli.ContainerStart(ctx, resp.ID, types.ContainerStartOptions{}); err != nil {
		log.Errorf("%v: could not start container: %v", idStr, err)
		return
	}

	log.Debugf("%v: container started", idStr)
	log.Debugf("%v: waiting on container", idStr)

	statusCh, errCh := cli.ContainerWait(ctx, resp.ID, container.WaitConditionNotRunning)
	select {
	case err := <-errCh:
		if err != nil {
			log.Errorf("%v: container returned error: %v", idStr, err)
			return
		}
	case okBody := <-statusCh:
		if okBody.Error != nil {
			log.Errorf("%v: could not wait on container: %v", idStr, err)
			return
		} else {
			log.Debugf("%v: container finished running with return code: %v", idStr, okBody.StatusCode)
			pe.Run.Result = &okBody.StatusCode
		}
	}

	pe.Run.InProgress = false

	log.Debugf("%v: getting container logs", idStr)

	out, err := cli.ContainerLogs(ctx, resp.ID, types.ContainerLogsOptions{ShowStdout: true, ShowStderr: true})
	if err != nil {
		log.Errorf("%v: could not get container logs: %w", idStr, err)
		return
	}

	log.Debugf("%v: gotcontainer logs", idStr)

	var stdOut bytes.Buffer
	var stdErr bytes.Buffer

	stdcopy.StdCopy(&stdOut, &stdErr, out)

	pe.Run.Stdout = stdOut.Bytes()
	pe.Run.Stderr = stdErr.Bytes()

	db.UpdateRunResult(pe.Run)

	return
}