package config

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

	"k8s.io/client-go/util/homedir"
)

var (
	// These values are globals to reduce the size of the refactor.
	// These should be passed around
	home                               = homedir.HomeDir()
	defaultPorterConfigFileName string = "porter.yaml"
	defaultPorterConfigDir      string = filepath.Join(home, ".porter")
	porterConfigFilePath        string = filepath.Clean(filepath.Join(defaultPorterConfigDir, defaultPorterConfigFileName))
	// currentProfile is used to set the profile for which any applied setting should be read or set
	currentProfile string = "default"
)

// CLIConfig is the set of shared configuration options for the CLI commands.
// This config is used by viper: calling Set() function for any parameter will
// update the corresponding field in the viper config file.
type CLIConfig struct {
	// Driver can be either "docker" or "local", and represents which driver is
	// used to run an instance of the server.
	Driver     string `yaml:"driver" env:"PORTER_DRIVER"`
	Host       string `yaml:"host" env:"PORTER_HOST"`
	Project    uint   `yaml:"project" env:"PORTER_PROJECT"`
	Cluster    uint   `yaml:"cluster" env:"PORTER_CLUSTER"`
	Token      string `yaml:"token" env:"PORTER_TOKEN"`
	Registry   uint   `yaml:"registry" env:"PORTER_REGISTRY"`
	HelmRepo   uint   `yaml:"helm_repo" env:"PORTER_HELM_REPO"`
	Kubeconfig string `yaml:"kubeconfig" env:"PORTER_KUBECONFIG"`
}

// FeatureFlags are any flags that are relevant to the feature set of the CLI. This should not include all feature flags, only those relevant to client-side CLI operations
type FeatureFlags struct {
	// ValidateApplyV2Enabled is a project-wide flag for checking if `porter apply` with porter.yaml is enabled
	ValidateApplyV2Enabled bool
}

// InitAndLoadConfig populates the config object with the following precedence rules:
// 1. flag
// 2. env
// 3. config
// 4. default
// If flagsConfig and envConfig are empty, then the default values or config file values will be preferred.
// This returns the config which should be applied to all subsequent requests, as well as the current profile that the command was run with.
// If no flagsProfile and flagsConfig are provided, this will follow the above precendence order to find values.
func InitAndLoadConfig(ctx context.Context, flagsProfile string, flagsConfig CLIConfig) (CLIConfig, string, error) {
	var config CLIConfig

	err := ensurePorterConfigDirectoryExists()
	if err != nil {
		return config, "", fmt.Errorf("unable to get or create porter directory: %w", err)
	}
	err = ensurePorterConfigFileExists()
	if err != nil {
		return config, "", fmt.Errorf("unable to get or create porter config file: %w", err)
	}

	defaultConfig := defaultCLIConfig()
	currentProfile := defaultProfileName
	if currentProfile != "" {
		currentProfile = flagsProfile
	}

	currentProfileConfig, configFileProfile, err := configForProfileFromConfigFile(currentProfile, porterConfigFilePath)
	if err != nil {
		return config, currentProfile, fmt.Errorf("unable to read profile variables from config file")
	}

	if currentProfile != "" {
		currentProfile = flagsProfile
	}

	envProfile := os.Getenv("PORTER_PROFILE")
	if envProfile != "" {
		currentProfile = envProfile
	}
	if flagsProfile != "" {
		currentProfile = flagsProfile
	}

	overlayedCurrentProfileConfig, err := overlayProfiles(defaultConfig, currentProfileConfig)
	if err != nil {
		return config, currentProfile, fmt.Errorf("unable to overlay profile onto default values")
	}
	fmt.Println(currentProfile, configFileProfile, flagsProfile, overlayedCurrentProfileConfig.Host, currentProfileConfig.Host)

	envVarsConfig, err := profileConfigFromEnvVars(ctx)
	if err != nil {
		return config, currentProfile, fmt.Errorf("unable to read profile variables from env vars")
	}

	overlayedEnvVarsConfig, err := overlayProfiles(overlayedCurrentProfileConfig, envVarsConfig)
	if err != nil {
		return config, currentProfile, fmt.Errorf("unable to overlay env vars profile onto values in porter config file")
	}

	configWithAllOverlays, err := overlayProfiles(overlayedEnvVarsConfig, flagsConfig)
	if err != nil {
		return config, currentProfile, fmt.Errorf("unable to overlay onto env vars config values onto flag values values")
	}

	return configWithAllOverlays, currentProfile, nil
}