package chain

import (
	"fmt"
	"io"
	"os"
	"path/filepath"
	"strings"

	"gopkg.in/yaml.v3"

	v0 "git.cw.tr/mukan-network/mukan-ignite/ignite/config/chain/v0"
	v1 "git.cw.tr/mukan-network/mukan-ignite/ignite/config/chain/v1"
	"git.cw.tr/mukan-network/mukan-ignite/ignite/config/chain/version"
)

var (
	// ConfigFilenames is a list of recognized names as Ignite's chain config file.
	ConfigFilenames = []string{"config.yml", "config.yaml"}

	// DefaultTSClientPath defines the default relative path to use when generating the TS client.
	// The path is relative to the app's directory.
	DefaultTSClientPath = "ts-client"

	// DefaultVuePath defines the default relative path to use when scaffolding a Vue app.
	// The path is relative to the app's directory.
	DefaultVuePath = "vue"

	// DefaultComposablesPath defines the default relative path to use when generating useQuery composables for a Vue app.
	// The path is relative to the app's directory.
	DefaultComposablesPath = "vue/src/composables"

	// DefaultVueTypesPath defines the default vue types path.
	DefaultVueTypesPath = "vue/src/views/Types.vue"

	// DefaultOpenAPIPath defines the default relative path to use when generating an OpenAPI schema.
	// The path is relative to the app's directory.
	DefaultOpenAPIPath = "docs/static/openapi.json"

	// LatestVersion defines the latest version of the config.
	LatestVersion version.Version = 1

	// Versions holds config types for the supported versions.
	Versions = map[version.Version]version.Converter{
		0: &v0.Config{},
		1: &v1.Config{},
	}
)

type (
	// Config defines the latest chain config.
	Config = v1.Config

	// Validator defines the latest validator settings.
	Validator = v1.Validator
)

// DefaultChainConfig returns a config for the latest version initialized with default values.
func DefaultChainConfig() *Config {
	return v1.DefaultConfig()
}

// FaucetHost returns the faucet host to use.
func FaucetHost(cfg *Config) string {
	// We keep supporting Port option for backward compatibility
	// TODO: drop this option in the future
	host := cfg.Faucet.Host
	if cfg.Faucet.Port != uint(0) {
		host = fmt.Sprintf(":%d", cfg.Faucet.Port)
	}

	return host
}

// TSClientPath returns the relative path to the Typescript client directory.
// Path is relative to the app's directory.
func TSClientPath(conf Config) string {
	if path := strings.TrimSpace(conf.Client.Typescript.Path); path != "" {
		return filepath.Clean(path)
	}

	return DefaultTSClientPath
}

// ComposablesPath returns the relative path to the Vue useQuery composables directory.
// Path is relative to the app's directory.
func ComposablesPath(conf *Config) string {
	if path := strings.TrimSpace(conf.Client.Composables.Path); path != "" {
		return filepath.Clean(path)
	}

	return DefaultComposablesPath
}

// LocateDefault locates the default path for the config file.
// Returns ErrConfigNotFound when no config file found.
func LocateDefault(root string) (path string, err error) {
	for _, name := range ConfigFilenames {
		path = filepath.Join(root, name)
		if _, err := os.Stat(path); err == nil {
			return path, nil
		} else if !os.IsNotExist(err) {
			return "", err
		}
	}

	return "", ErrConfigNotFound
}

// CheckVersion checks that the config version is the latest
// and if not a VersionError is returned.
func CheckVersion(configFile io.Reader) error {
	version, err := ReadConfigVersion(configFile)
	if err != nil {
		return err
	}

	if version != LatestVersion {
		return VersionError{version}
	}

	return nil
}

// Save saves a config to a YAML file.
func Save(c Config, path string) error {
	file, err := os.OpenFile(path, os.O_WRONLY|os.O_TRUNC, 0o755)
	if err != nil {
		return err
	}

	defer file.Close()

	return yaml.NewEncoder(file).Encode(c)
}

// FirstValidator returns the first validator from the validators list.
// An error is returned when there are no validators defined in the config.
func FirstValidator(conf *Config) (Validator, error) {
	if len(conf.Validators) == 0 {
		return Validator{}, &ValidationError{"at least one validator is required"}
	}

	return conf.Validators[0], nil
}