package workflows

import (
	"context"
	"fmt"
	"log/slog"

	"go.temporal.io/sdk/client"
)

// ClientConfig holds configuration for the Temporal client.
type ClientConfig struct {
	HostPort           string
	Namespace          string
	Logger             *slog.Logger
	OAuthTokenProvider *OAuthTokenProviderConfig
}

// DefaultClientConfig returns a ClientConfig with sensible defaults.
func DefaultClientConfig() ClientConfig {
	return ClientConfig{
		HostPort:  "localhost:7233",
		Namespace: "default",
	}
}

// NewClient creates a new Temporal client.
func NewClient(ctx context.Context, cfg ClientConfig) (client.Client, error) {
	if cfg.HostPort == "" {
		cfg.HostPort = "localhost:7233"
	}
	if cfg.Namespace == "" {
		cfg.Namespace = "default"
	}

	opts := client.Options{
		HostPort:  cfg.HostPort,
		Namespace: cfg.Namespace,
	}

	if cfg.OAuthTokenProvider != nil {
		headersProvider, err := NewOAuthTokenProvider(*cfg.OAuthTokenProvider)
		if err != nil {
			return nil, fmt.Errorf("failed to configure Temporal auth: %w", err)
		}
		opts.HeadersProvider = headersProvider
	}

	if cfg.Logger != nil {
		opts.Logger = newSlogAdapter(cfg.Logger)
	}

	c, err := client.Dial(opts)
	if err != nil {
		return nil, fmt.Errorf("failed to create Temporal client: %w", err)
	}

	if cfg.Logger != nil {
		cfg.Logger.Info("connected to Temporal server",
			slog.String("host", cfg.HostPort),
			slog.String("namespace", cfg.Namespace))
	}

	return c, nil
}

// slogAdapter adapts slog.Logger to Temporal's log.Logger interface.
type slogAdapter struct {
	logger *slog.Logger
}

func newSlogAdapter(logger *slog.Logger) *slogAdapter {
	return &slogAdapter{logger: logger}
}

func (s *slogAdapter) Debug(msg string, keyvals ...interface{}) {
	s.logger.Debug(msg, keyvals...)
}

func (s *slogAdapter) Info(msg string, keyvals ...interface{}) {
	s.logger.Info(msg, keyvals...)
}

func (s *slogAdapter) Warn(msg string, keyvals ...interface{}) {
	s.logger.Warn(msg, keyvals...)
}

func (s *slogAdapter) Error(msg string, keyvals ...interface{}) {
	s.logger.Error(msg, keyvals...)
}