Scaffold project

internal/providers/providers.go

@@ -0,0 +1,78 @@
+package providers
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/yourusername/go-llm-gateway/internal/api"
+	"github.com/yourusername/go-llm-gateway/internal/config"
+	anthropicprovider "github.com/yourusername/go-llm-gateway/internal/providers/anthropic"
+	googleprovider "github.com/yourusername/go-llm-gateway/internal/providers/google"
+	openaiprovider "github.com/yourusername/go-llm-gateway/internal/providers/openai"
+)
+
+// Provider represents a unified interface that each LLM provider must implement.
+type Provider interface {
+	Name() string
+	Generate(ctx context.Context, req *api.ResponseRequest) (*api.Response, error)
+	GenerateStream(ctx context.Context, req *api.ResponseRequest) (<-chan *api.StreamChunk, <-chan error)
+}
+
+// Registry keeps track of registered providers by key (e.g. "openai").
+type Registry struct {
+	providers map[string]Provider
+}
+
+// NewRegistry constructs provider implementations from configuration.
+func NewRegistry(cfg config.ProvidersConfig) (*Registry, error) {
+	reg := &Registry{providers: make(map[string]Provider)}
+
+	if cfg.Google.APIKey != "" {
+		reg.providers[googleprovider.Name] = googleprovider.New(cfg.Google)
+	}
+	if cfg.Anthropic.APIKey != "" {
+		reg.providers[anthropicprovider.Name] = anthropicprovider.New(cfg.Anthropic)
+	}
+	if cfg.OpenAI.APIKey != "" {
+		reg.providers[openaiprovider.Name] = openaiprovider.New(cfg.OpenAI)
+	}
+
+	if len(reg.providers) == 0 {
+		return nil, fmt.Errorf("no providers configured")
+	}
+
+	return reg, nil
+}
+
+// Get returns provider by key.
+func (r *Registry) Get(name string) (Provider, bool) {
+	p, ok := r.providers[name]
+	return p, ok
+}
+
+// Default returns provider based on inferred name.
+func (r *Registry) Default(model string) (Provider, error) {
+	if model != "" {
+		switch {
+		case strings.HasPrefix(model, "gpt") || strings.HasPrefix(model, "o1"):
+			if p, ok := r.providers[openaiprovider.Name]; ok {
+				return p, nil
+			}
+		case strings.HasPrefix(model, "claude"):
+			if p, ok := r.providers[anthropicprovider.Name]; ok {
+				return p, nil
+			}
+		case strings.HasPrefix(model, "gemini"):
+			if p, ok := r.providers[googleprovider.Name]; ok {
+				return p, nil
+			}
+		}
+	}
+
+	for _, p := range r.providers {
+		return p, nil
+	}
+
+	return nil, fmt.Errorf("no providers available")
+}