package v2

import (
	"context"
	"encoding/base64"
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"strconv"
	"time"

	"github.com/porter-dev/porter/api/server/handlers/porter_app"
	"github.com/porter-dev/porter/api/types"

	"github.com/cli/cli/git"

	"github.com/fatih/color"
	"github.com/porter-dev/api-contracts/generated/go/helpers"
	porterv1 "github.com/porter-dev/api-contracts/generated/go/porter/v1"
	api "github.com/porter-dev/porter/api/client"
	"github.com/porter-dev/porter/cli/cmd/config"
)

// Apply implements the functionality of the `porter apply` command for validate apply v2 projects
func Apply(ctx context.Context, cliConf config.CLIConfig, client api.Client, porterYamlPath string, appName string) error {
	var yamlB64 string
	if len(porterYamlPath) != 0 {
		porterYaml, err := os.ReadFile(filepath.Clean(porterYamlPath))
		if err != nil {
			return fmt.Errorf("could not read porter yaml file: %w", err)
		}

		b64YAML := base64.StdEncoding.EncodeToString(porterYaml)

		// last argument is passed to accommodate users with v1 porter yamls
		parseResp, err := client.ParseYAML(ctx, cliConf.Project, cliConf.Cluster, b64YAML, appName)
		if err != nil {
			return fmt.Errorf("error calling parse yaml endpoint: %w", err)
		}

		if parseResp.B64AppProto == "" {
			return errors.New("b64 app proto is empty")
		}
		yamlB64 = parseResp.B64AppProto

		// override app name if provided
		appName, err = appNameFromB64AppProto(parseResp.B64AppProto)
		if err != nil {
			return fmt.Errorf("error getting app name from b64 app proto: %w", err)
		}

		color.New(color.FgGreen).Printf("Successfully parsed Porter YAML: applying app \"%s\"\n", appName) // nolint:errcheck,gosec
	}

	targetResp, err := client.DefaultDeploymentTarget(ctx, cliConf.Project, cliConf.Cluster)
	if err != nil {
		return fmt.Errorf("error calling default deployment target endpoint: %w", err)
	}

	if targetResp.DeploymentTargetID == "" {
		return errors.New("deployment target id is empty")
	}

	var commitSHA string
	if os.Getenv("PORTER_COMMIT_SHA") != "" {
		commitSHA = os.Getenv("PORTER_COMMIT_SHA")
	} else if os.Getenv("GITHUB_SHA") != "" {
		commitSHA = os.Getenv("GITHUB_SHA")
	} else if commit, err := git.LastCommit(); err == nil && commit != nil {
		commitSHA = commit.Sha
	}

	validateResp, err := client.ValidatePorterApp(ctx, cliConf.Project, cliConf.Cluster, appName, yamlB64, targetResp.DeploymentTargetID, commitSHA)
	if err != nil {
		return fmt.Errorf("error calling validate endpoint: %w", err)
	}

	if validateResp.ValidatedBase64AppProto == "" {
		return errors.New("validated b64 app proto is empty")
	}
	base64AppProto := validateResp.ValidatedBase64AppProto

	createPorterAppDBEntryInp, err := createPorterAppDbEntryInputFromProtoAndEnv(validateResp.ValidatedBase64AppProto)
	if err != nil {
		return fmt.Errorf("error creating porter app db entry input from proto: %w", err)
	}

	err = client.CreatePorterAppDBEntry(ctx, cliConf.Project, cliConf.Cluster, createPorterAppDBEntryInp)
	if err != nil {
		return fmt.Errorf("error creating porter app db entry: %w", err)
	}

	applyResp, err := client.ApplyPorterApp(ctx, cliConf.Project, cliConf.Cluster, base64AppProto, targetResp.DeploymentTargetID, "")
	if err != nil {
		return fmt.Errorf("error calling apply endpoint: %w", err)
	}

	if applyResp.AppRevisionId == "" {
		return errors.New("app revision id is empty")
	}

	if applyResp.CLIAction == porterv1.EnumCLIAction_ENUM_CLI_ACTION_BUILD {
		color.New(color.FgGreen).Printf("Building new image...\n") // nolint:errcheck,gosec

		eventID, _ := createBuildEvent(ctx, client, appName, cliConf.Project, cliConf.Cluster, targetResp.DeploymentTargetID)

		if commitSHA == "" {
			return errors.New("Build is required but commit SHA cannot be identified. Please set the PORTER_COMMIT_SHA environment variable or run apply in git repository with access to the git CLI.")
		}

		buildSettings, err := buildSettingsFromBase64AppProto(base64AppProto)
		if err != nil {
			return fmt.Errorf("error building settings from base64 app proto: %w", err)
		}

		currentAppRevisionResp, err := client.CurrentAppRevision(ctx, cliConf.Project, cliConf.Cluster, appName, targetResp.DeploymentTargetID)
		if err != nil {
			return fmt.Errorf("error getting current app revision: %w", err)
		}

		if currentAppRevisionResp == nil {
			return errors.New("current app revision is nil")
		}

		appRevision := currentAppRevisionResp.AppRevision
		if appRevision.B64AppProto == "" {
			return errors.New("current app revision b64 app proto is empty")
		}

		currentImageTag, err := imageTagFromBase64AppProto(appRevision.B64AppProto)
		if err != nil {
			return fmt.Errorf("error getting image tag from current app revision: %w", err)
		}

		buildSettings.CurrentImageTag = currentImageTag
		buildSettings.ProjectID = cliConf.Project

		err = build(ctx, client, buildSettings)
		buildMetadata := make(map[string]interface{})
		buildMetadata["end_time"] = time.Now().UTC()

		if err != nil {
			_ = updateExistingEvent(ctx, client, appName, cliConf.Project, cliConf.Cluster, targetResp.DeploymentTargetID, eventID, types.PorterAppEventStatus_Failed, buildMetadata)
			return fmt.Errorf("error building app: %w", err)
		}

		color.New(color.FgGreen).Printf("Successfully built image (tag: %s)\n", buildSettings.ImageTag) // nolint:errcheck,gosec

		_ = updateExistingEvent(ctx, client, appName, cliConf.Project, cliConf.Cluster, targetResp.DeploymentTargetID, eventID, types.PorterAppEventStatus_Success, buildMetadata)

		applyResp, err = client.ApplyPorterApp(ctx, cliConf.Project, cliConf.Cluster, "", "", applyResp.AppRevisionId)
		if err != nil {
			return fmt.Errorf("apply error post-build: %w", err)
		}
	}

	color.New(color.FgGreen).Printf("Image tag exists in repository\n") // nolint:errcheck,gosec

	if applyResp.CLIAction == porterv1.EnumCLIAction_ENUM_CLI_ACTION_TRACK_PREDEPLOY {
		color.New(color.FgGreen).Printf("Waiting for predeploy to complete...\n") // nolint:errcheck,gosec

		now := time.Now().UTC()
		eventID, _ := createPredeployEvent(ctx, client, appName, cliConf.Project, cliConf.Cluster, targetResp.DeploymentTargetID, now, applyResp.AppRevisionId)

		eventStatus := types.PorterAppEventStatus_Success
		for {
			if time.Since(now) > checkPredeployTimeout {
				return errors.New("timed out waiting for predeploy to complete")
			}

			predeployStatusResp, err := client.PredeployStatus(ctx, cliConf.Project, cliConf.Cluster, appName, applyResp.AppRevisionId)
			if err != nil {
				return fmt.Errorf("error calling predeploy status endpoint: %w", err)
			}

			if predeployStatusResp.Status == porter_app.PredeployStatus_Failed {
				eventStatus = types.PorterAppEventStatus_Failed
				break
			}
			if predeployStatusResp.Status == porter_app.PredeployStatus_Successful {
				break
			}

			time.Sleep(checkPredeployFrequency)
		}

		metadata := make(map[string]interface{})
		metadata["end_time"] = time.Now().UTC()
		_ = updateExistingEvent(ctx, client, appName, cliConf.Project, cliConf.Cluster, targetResp.DeploymentTargetID, eventID, eventStatus, metadata)

		applyResp, err = client.ApplyPorterApp(ctx, cliConf.Project, cliConf.Cluster, "", "", applyResp.AppRevisionId)
		if err != nil {
			return fmt.Errorf("apply error post-predeploy: %w", err)
		}
	}

	if applyResp.CLIAction != porterv1.EnumCLIAction_ENUM_CLI_ACTION_NONE {
		return fmt.Errorf("unexpected CLI action: %s", applyResp.CLIAction)
	}

	color.New(color.FgGreen).Printf("Successfully applied new revision %s for app %s\n", applyResp.AppRevisionId, appName) // nolint:errcheck,gosec
	return nil
}

// checkPredeployTimeout is the maximum amount of time the CLI will wait for a predeploy to complete before calling apply again
const checkPredeployTimeout = 60 * time.Minute

// checkPredeployFrequency is the frequency at which the CLI will check the status of a predeploy
const checkPredeployFrequency = 10 * time.Second

func appNameFromB64AppProto(base64AppProto string) (string, error) {
	decoded, err := base64.StdEncoding.DecodeString(base64AppProto)
	if err != nil {
		return "", fmt.Errorf("unable to decode base64 app for revision: %w", err)
	}

	app := &porterv1.PorterApp{}
	err = helpers.UnmarshalContractObject(decoded, app)
	if err != nil {
		return "", fmt.Errorf("unable to unmarshal app for revision: %w", err)
	}

	if app.Name == "" {
		return "", fmt.Errorf("app does not contain name")
	}
	return app.Name, nil
}

func createPorterAppDbEntryInputFromProtoAndEnv(base64AppProto string) (api.CreatePorterAppDBEntryInput, error) {
	var input api.CreatePorterAppDBEntryInput

	decoded, err := base64.StdEncoding.DecodeString(base64AppProto)
	if err != nil {
		return input, fmt.Errorf("unable to decode base64 app for revision: %w", err)
	}

	app := &porterv1.PorterApp{}
	err = helpers.UnmarshalContractObject(decoded, app)
	if err != nil {
		return input, fmt.Errorf("unable to unmarshal app for revision: %w", err)
	}

	if app.Name == "" {
		return input, fmt.Errorf("app does not contain name")
	}
	input.AppName = app.Name

	if app.Build != nil {
		if os.Getenv("GITHUB_REPOSITORY_ID") == "" {
			input.Local = true
			return input, nil
		}
		gitRepoId, err := strconv.Atoi(os.Getenv("GITHUB_REPOSITORY_ID"))
		if err != nil {
			return input, fmt.Errorf("unable to parse GITHUB_REPOSITORY_ID to int: %w", err)
		}
		input.GitRepoID = uint(gitRepoId)
		input.GitRepoName = os.Getenv("GITHUB_REPOSITORY")
		input.GitBranch = os.Getenv("GITHUB_REF_NAME")
		input.PorterYamlPath = "porter.yaml"
		return input, nil
	}

	if app.Image != nil {
		input.ImageRepository = app.Image.Repository
		input.ImageTag = app.Image.Tag
		return input, nil
	}

	return input, fmt.Errorf("app does not contain build or image settings")
}

func buildSettingsFromBase64AppProto(base64AppProto string) (buildInput, error) {
	var buildSettings buildInput

	decoded, err := base64.StdEncoding.DecodeString(base64AppProto)
	if err != nil {
		return buildSettings, fmt.Errorf("unable to decode base64 app for revision: %w", err)
	}

	app := &porterv1.PorterApp{}
	err = helpers.UnmarshalContractObject(decoded, app)
	if err != nil {
		return buildSettings, fmt.Errorf("unable to unmarshal app for revision: %w", err)
	}

	if app.Name == "" {
		return buildSettings, fmt.Errorf("app does not contain name")
	}

	if app.Build == nil {
		return buildSettings, fmt.Errorf("app does not contain build settings")
	}

	if app.Image == nil {
		return buildSettings, fmt.Errorf("app does not contain image settings")
	}

	return buildInput{
		AppName:       app.Name,
		BuildContext:  app.Build.Context,
		Dockerfile:    app.Build.Dockerfile,
		BuildMethod:   app.Build.Method,
		Builder:       app.Build.Builder,
		BuildPacks:    app.Build.Buildpacks,
		ImageTag:      app.Image.Tag,
		RepositoryURL: app.Image.Repository,
	}, nil
}

func imageTagFromBase64AppProto(base64AppProto string) (string, error) {
	var image string

	decoded, err := base64.StdEncoding.DecodeString(base64AppProto)
	if err != nil {
		return image, fmt.Errorf("unable to decode base64 app for revision: %w", err)
	}

	app := &porterv1.PorterApp{}
	err = helpers.UnmarshalContractObject(decoded, app)
	if err != nil {
		return image, fmt.Errorf("unable to unmarshal app for revision: %w", err)
	}

	if app.Image == nil {
		return image, fmt.Errorf("app does not contain image settings")
	}

	if app.Image.Tag == "" {
		return image, fmt.Errorf("app does not contain image tag")
	}

	return app.Image.Tag, nil
}