package commands

import (
	"context"
	"fmt"
	"os"

	"github.com/fatih/color"
	api "github.com/porter-dev/porter/api/client"
	"github.com/porter-dev/porter/api/types"
	"github.com/porter-dev/porter/cli/cmd/config"
	"github.com/spf13/cobra"
)

var (
	appName      string
	envGroupName string
	envFilePath  string
)

type envVariables struct {
	Variables map[string]string `json:"variables"`
	Secrets   map[string]string `json:"secrets"`
}

func registerCommand_Env(cliConf config.CLIConfig) *cobra.Command {
	envCmd := &cobra.Command{
		Use:   "env",
		Args:  cobra.MinimumNArgs(1),
		Short: "Manage environment variables for a project",
		RunE: func(cmd *cobra.Command, args []string) error {
			return cmd.Help()
		},
	}

	pullCommand := &cobra.Command{
		Use:   "pull",
		Short: "Pull environment variables for an app or environment group",
		Long: `Pull environment variables for an app or environment group. 

Optionally, specify a file to write the environment variables to. Otherwise the environment variables will be written to stdout.`,
		Args: cobra.NoArgs,
		RunE: func(cmd *cobra.Command, args []string) error {
			return checkLoginAndRunWithConfig(cmd, cliConf, args, pullEnv)
		},
	}

	pullCommand.Flags().StringVarP(&appName, "app", "a", "", "app name")
	pullCommand.Flags().StringVarP(&envGroupName, "group", "g", "", "environment group name")
	pullCommand.Flags().StringVarP(&envFilePath, "file", "f", "", "file to write environment variables to")
	pullCommand.Flags().StringVarP(&deploymentTargetName, "target", "x", "", "the name of the deployment target for the app")

	envCmd.AddCommand(pullCommand)

	return envCmd
}

func pullEnv(ctx context.Context, user *types.GetAuthenticatedUserResponse, client api.Client, cliConf config.CLIConfig, featureFlags config.FeatureFlags, cmd *cobra.Command, args []string) error {
	if appName == "" && envGroupName == "" {
		return fmt.Errorf("must specify either --app or --group")
	}
	if appName != "" && envGroupName != "" {
		return fmt.Errorf("only one of --app or --group can be specified")
	}

	var envVars envVariables

	if appName != "" {
		color.New(color.FgGreen).Printf("Pulling environment variables for app %s...\n", appName) // nolint:errcheck,gosec

		envVarsResp, err := client.GetAppEnvVariables(ctx, cliConf.Project, cliConf.Cluster, appName, deploymentTargetName)
		if err != nil {
			return fmt.Errorf("could not get app env variables: %w", err)
		}
		if envVarsResp == nil {
			return fmt.Errorf("could not get app env variables: response was nil")
		}

		envVars = envVariables{
			Variables: envVarsResp.EnvVariables.Variables,
			Secrets:   envVarsResp.EnvVariables.Secrets,
		}
	}

	if envGroupName != "" {
		color.New(color.FgGreen).Printf("Pulling environment variables for environment group %s...\n", envGroupName) // nolint:errcheck,gosec

		envVarsResp, err := client.GetLatestEnvGroupVariables(ctx, cliConf.Project, cliConf.Cluster, envGroupName)
		if err != nil {
			return fmt.Errorf("could not get env group env variables: %w", err)
		}
		if envVarsResp == nil {
			return fmt.Errorf("could not get env group variables: response was nil")
		}

		envVars = envVariables{
			Variables: envVarsResp.Variables,
			Secrets:   envVarsResp.Secrets,
		}
	}

	if envFilePath != "" {
		err := writeEnvFile(envFilePath, envVars)
		if err != nil {
			return fmt.Errorf("could not write env file: %w", err)
		}
		color.New(color.FgGreen).Printf("Wrote environment variables to %s\n", envFilePath) // nolint:errcheck,gosec
	}

	if envFilePath == "" {
		err := exportEnvVars(envVars)
		if err != nil {
			return fmt.Errorf("could not export env vars: %w", err)
		}
	}

	return nil
}

func writeEnvFile(envFilePath string, envVars envVariables) error {
	// open existing file or create new file: https://pkg.go.dev/os#example-OpenFile-Append
	envFile, err := os.OpenFile(envFilePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o644) // nolint:gosec
	if err != nil {
		return err
	}
	defer envFile.Close() // nolint:errcheck

	_, err = envFile.WriteString("# Generated by Porter CLI\n")
	if err != nil {
		return err
	}

	for k, v := range envVars.Variables {
		_, err := envFile.WriteString(fmt.Sprintf("%s=%s\n", k, v))
		if err != nil {
			return err
		}
	}

	for k, v := range envVars.Secrets {
		_, err := envFile.WriteString(fmt.Sprintf("%s=%s\n", k, v))
		if err != nil {
			return err
		}
	}

	return nil
}

func exportEnvVars(envVars envVariables) error {
	for k, v := range envVars.Variables {
		_, err := os.Stdout.WriteString(fmt.Sprintf("%s=%s\n", k, v))
		if err != nil {
			return err
		}
	}

	for k, v := range envVars.Secrets {
		_, err := os.Stdout.WriteString(fmt.Sprintf("%s=%s\n", k, v))
		if err != nil {
			return err
		}
	}

	return nil
}