package main

import (
	"encoding/json"
	"io/ioutil"
	"log"
	"os"

	"github.com/a8m/envsubst"
	"github.com/asaskevich/govalidator"
	"github.com/caarlos0/env/v6"
	"github.com/urfave/cli/v2"
)

func init() {
	log.SetFlags(log.LstdFlags | log.Lshortfile)
}

func parseManifest(manifestPath string) (*Manifest, error) {
	rawManifest, err := ioutil.ReadFile(manifestPath)
	if err != nil {
		log.Fatalf("\nErr: %v", err)
		return nil, err
	}

	//Do Environment substitution
	manifestWithEnvironment, err := envsubst.Bytes(rawManifest)
	if err != nil {
		log.Fatalf("\nErr: %v", err)
		return nil, err
	}

	var manifest Manifest
	err = json.Unmarshal(manifestWithEnvironment, &manifest)
	if err != nil {
		log.Fatalf("\nErr: %v", err)
		return nil, err
	}

	err = env.Parse(&manifest)
	if err != nil {
		log.Fatalf("\nErr: %v", err)
		return nil, err
	}

	_, err = govalidator.ValidateStruct(manifest)
	if err != nil {
		log.Fatalf("\nErr: %v", err.Error())
		return nil, err
	}

	if manifest.ExtraResources.Environment == "" {
		manifest.ExtraResources.Environment = manifest.Environment
	}
	if manifest.ExtraResources.Workspace == "" {
		manifest.ExtraResources.Workspace = workspaceMap[manifest.ExtraResources.Environment]
	}

	if manifest.Deployment == nil {
		manifest.Deployment = &Deployment{}
	}
	manifest.Deployment.NameSuffix = DeploymentNameSuffix

	//Fix: Required for templating storage backend
	var stateStoreBucketName = storageBackendBucketMap[manifest.ExtraResources.Environment]
	manifest.StateStoreBackend = &StateStoreBackend{
		BucketName: stateStoreBucketName,
		AWSProfile: storageBackendAWSProfileMap[stateStoreBucketName],
	}
	return &manifest, nil
}

func main() {
	app := &cli.App{
		Name:    "infra-provisioner",
		Version: "0.0.1",

		//Common flags for all subcommands
		Flags: []cli.Flag{
			&cli.StringFlag{
				Name:     "manifest",
				Usage:    "Path of the manifest file",
				Aliases:  []string{"m"},
				Required: true,
			},
			&cli.BoolFlag{
				Name:    "template-only",
				Usage:   "Provisions just the template for given resource",
				Aliases: []string{"t"},
			},
			&cli.BoolFlag{
				Name:    "plan",
				Usage:   "Run plan for the given resources",
				Aliases: []string{"p"},
			},
		},

		Commands: []*cli.Command{
			{
				Name:  "database",
				Usage: "Provision database instance",
				Action: func(c *cli.Context) error {
					manifest, err := parseManifest(c.String("manifest"))
					if err != nil {
						log.Fatalf("\nErr: %v", err)
						return err
					}
					err = provisionResource("rds", "rds-tf", manifest, c.Bool("template-only"), c.Bool("plan"))
					if err != nil {
						log.Fatalf("\nErr: %v", err)
						return err
					}
					return nil
				},
			},
			{
				Name:  "iam-roles",
				Usage: "Provision iam service roles",
				Action: func(c *cli.Context) error {
					manifest, err := parseManifest(c.String("manifest"))
					if err != nil {
						log.Fatalf("\nErr: %v", err)
						return err
					}
					err = provisionResource("roles", "aws-roles-tf", manifest, c.Bool("template-only"), c.Bool("plan"))
					if err != nil {
						log.Fatalf("\nErr: %v", err)
						return err
					}
					return nil
				},
			},
			{
				Name:  "s3-buckets",
				Usage: "Provision s3 buckets",
				Action: func(c *cli.Context) error {
					manifest, err := parseManifest(c.String("manifest"))
					if err != nil {
						log.Fatalf("\nErr: %v", err)
						return err
					}
					err = provisionResource("s3", "aws-s3-bucket-tf", manifest, c.Bool("template-only"), c.Bool("plan"))
					if err != nil {
						log.Fatalf("\nErr: %v", err)
						return err
					}
					return nil
				},
			},
		},
	}

	app.Run(os.Args)
}