package importKey

import (
	"context"
	"encoding/base64"
	"encoding/json"
	"fmt"

	"github.com/stackitcloud/stackit-cli/internal/pkg/types"

	"github.com/goccy/go-yaml"
	"github.com/spf13/cobra"
	"github.com/stackitcloud/stackit-cli/internal/pkg/args"
	cliErr "github.com/stackitcloud/stackit-cli/internal/pkg/errors"
	"github.com/stackitcloud/stackit-cli/internal/pkg/services/kms/client"
	kmsUtils "github.com/stackitcloud/stackit-cli/internal/pkg/services/kms/utils"
	"github.com/stackitcloud/stackit-cli/internal/pkg/utils"

	"github.com/stackitcloud/stackit-cli/internal/pkg/examples"
	"github.com/stackitcloud/stackit-cli/internal/pkg/flags"
	"github.com/stackitcloud/stackit-cli/internal/pkg/globalflags"
	"github.com/stackitcloud/stackit-cli/internal/pkg/print"
	"github.com/stackitcloud/stackit-sdk-go/services/kms"
)

const (
	keyIdArg = "KEY_ID"

	keyRingIdFlag     = "keyring-id"
	wrappedKeyFlag    = "wrapped-key"
	wrappingKeyIdFlag = "wrapping-key-id"
)

type inputModel struct {
	*globalflags.GlobalFlagModel
	KeyRingId     string
	KeyId         string
	WrappedKey    *string
	WrappingKeyId *string
}

func NewCmd(params *types.CmdParams) *cobra.Command {
	cmd := &cobra.Command{
		Use:   fmt.Sprintf("import %s", keyIdArg),
		Short: "Import a KMS key",
		Long:  "After encrypting the secret with the wrapping key’s public key and Base64-encoding it, import it as a new version of the specified KMS key.",
		Args:  args.SingleArg(keyIdArg, utils.ValidateUUID),
		Example: examples.Build(
			examples.NewExample(
				`Import a new version for the given KMS key "MY_KEY_ID" from literal value`,
				`$ stackit beta kms key import "MY_KEY_ID" --keyring-id "my-keyring-id" --wrapped-key "BASE64_VALUE" --wrapping-key-id "MY_WRAPPING_KEY_ID"`),
			examples.NewExample(
				`Import from a file`,
				`$ stackit beta kms key import "MY_KEY_ID" --keyring-id "my-keyring-id" --wrapped-key "@path/to/wrapped.key.b64" --wrapping-key-id "MY_WRAPPING_KEY_ID"`,
			),
		),

		RunE: func(cmd *cobra.Command, args []string) error {
			ctx := context.Background()
			model, err := parseInput(params.Printer, cmd, args)
			if err != nil {
				return err
			}

			// Configure API client
			apiClient, err := client.ConfigureClient(params.Printer, params.CliVersion)
			if err != nil {
				return err
			}

			keyName, err := kmsUtils.GetKeyName(ctx, apiClient, model.ProjectId, model.Region, model.KeyRingId, model.KeyId)
			if err != nil {
				params.Printer.Debug(print.ErrorLevel, "get key name: %v", err)
				keyName = model.KeyId
			}
			keyRingName, err := kmsUtils.GetKeyRingName(ctx, apiClient, model.ProjectId, model.KeyRingId, model.Region)
			if err != nil {
				params.Printer.Debug(print.ErrorLevel, "get key ring name: %v", err)
				keyRingName = model.KeyRingId
			}

			prompt := fmt.Sprintf("Are you sure you want to import a new version for the KMS Key %q inside the key ring %q?", keyName, keyRingName)
			err = params.Printer.PromptForConfirmation(prompt)
			if err != nil {
				return err
			}

			// Call API
			req, _ := buildRequest(ctx, model, apiClient)
			resp, err := req.Execute()
			if err != nil {
				return fmt.Errorf("import KMS key: %w", err)
			}

			return outputResult(params.Printer, model.OutputFormat, keyRingName, keyName, resp)
		},
	}
	configureFlags(cmd)
	return cmd
}

func parseInput(p *print.Printer, cmd *cobra.Command, inputArgs []string) (*inputModel, error) {
	keyId := inputArgs[0]

	globalFlags := globalflags.Parse(p, cmd)
	if globalFlags.ProjectId == "" {
		return nil, &cliErr.ProjectIdError{}
	}

	// WrappedKey needs to be base64 encoded
	var wrappedKey = flags.FlagToStringPointer(p, cmd, wrappedKeyFlag)
	_, err := base64.StdEncoding.DecodeString(*wrappedKey)
	if err != nil || *wrappedKey == "" {
		return nil, &cliErr.FlagValidationError{
			Flag:    wrappedKeyFlag,
			Details: "The 'wrappedKey' argument is required and needs to be base64 encoded (whether provided inline or via file).",
		}
	}

	model := inputModel{
		GlobalFlagModel: globalFlags,
		KeyId:           keyId,
		KeyRingId:       flags.FlagToStringValue(p, cmd, keyRingIdFlag),
		WrappedKey:      wrappedKey,
		WrappingKeyId:   flags.FlagToStringPointer(p, cmd, wrappingKeyIdFlag),
	}

	p.DebugInputModel(model)
	return &model, nil
}

type kmsKeyClient interface {
	ImportKey(ctx context.Context, projectId string, regionId string, keyRingId string, keyId string) kms.ApiImportKeyRequest
}

func buildRequest(ctx context.Context, model *inputModel, apiClient kmsKeyClient) (kms.ApiImportKeyRequest, error) {
	req := apiClient.ImportKey(ctx, model.ProjectId, model.Region, model.KeyRingId, model.KeyId)

	req = req.ImportKeyPayload(kms.ImportKeyPayload{
		WrappedKey:    model.WrappedKey,
		WrappingKeyId: model.WrappingKeyId,
	})
	return req, nil
}

func outputResult(p *print.Printer, outputFormat, keyRingName, keyName string, resp *kms.Version) error {
	if resp == nil {
		return fmt.Errorf("response is nil")
	}

	switch outputFormat {
	case print.JSONOutputFormat:
		details, err := json.MarshalIndent(resp, "", "  ")
		if err != nil {
			return fmt.Errorf("marshal KMS key: %w", err)
		}
		p.Outputln(string(details))

	case print.YAMLOutputFormat:
		details, err := yaml.MarshalWithOptions(resp, yaml.IndentSequence(true), yaml.UseJSONMarshaler())
		if err != nil {
			return fmt.Errorf("marshal KMS key: %w", err)
		}
		p.Outputln(string(details))

	default:
		p.Outputf("Imported a new version for the key %q inside the key ring %q\n", keyName, keyRingName)
	}

	return nil
}

func configureFlags(cmd *cobra.Command) {
	cmd.Flags().Var(flags.UUIDFlag(), keyRingIdFlag, "ID of the KMS key ring")
	cmd.Flags().Var(flags.ReadFromFileFlag(), wrappedKeyFlag, "The wrapped key material to be imported. Base64-encoded. Pass the value directly or a file path (e.g. @path/to/wrapped.key.b64)")
	cmd.Flags().Var(flags.UUIDFlag(), wrappingKeyIdFlag, "The unique id of the wrapping key the key material has been wrapped with")

	err := flags.MarkFlagsRequired(cmd, keyRingIdFlag, wrappedKeyFlag, wrappingKeyIdFlag)
	cobra.CheckErr(err)
}
