package agent

import (
	"fmt"
	"os"

	"github.com/VictorVargas/rony-llm-agent/pkg/llm"
	"github.com/VictorVargas/rony-llm-agent/pkg/llm/providers/anthropic"
	"github.com/VictorVargas/rony-llm-agent/pkg/llm/providers/llamacpp"
	"github.com/VictorVargas/rony-llm-agent/pkg/llm/providers/openai"

	"github.com/VictorVargas/rony-chat-bot/internal/config"
)

// NewClient constructs the upstream LLMClient for a given provider config.
// "ollama" is handled via the openai-compat adapter: Ollama exposes
// /v1/chat/completions on its own port, so the provider list stays small.
func NewClient(p config.Provider) (llm.LLMClient, error) {
	switch p.Type {
	case "llamacpp":
		return llamacpp.New(llamacpp.Config{
			BaseURL:       defaultIfEmpty(p.Endpoint, "http://localhost:8080/v1"),
			Model:         p.Model,
			ContextWindow: p.ContextSize,
			MaxTokens:     p.MaxTokens,
			Temperature:   p.Temperature,
		})
	case "ollama", "openai":
		return openai.New(openai.Config{
			BaseURL: defaultIfEmpty(p.Endpoint, "http://localhost:11434/v1"),
			Model:   p.Model,
		})
	case "anthropic":
		apiKey := ""
		if p.APIKeyEnv != "" {
			apiKey = os.Getenv(p.APIKeyEnv)
		}
		return anthropic.New(anthropic.Config{
			APIKey: apiKey,
			Model:  p.Model,
		})
	default:
		return nil, fmt.Errorf("unknown provider type %q (supported: llamacpp, ollama, openai, anthropic)", p.Type)
	}
}

func defaultIfEmpty(s, def string) string {
	if s == "" {
		return def
	}
	return s
}