Merge pull request #131 from Leeaandrob/feat/multi-agent-routing

feat: model fallback chain + multi-agent routing

Author: Leeaandrob

pkg/agent/instance.go

@@ -0,0 +1,145 @@
+package agent
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/sipeed/picoclaw/pkg/config"
+	"github.com/sipeed/picoclaw/pkg/providers"
+	"github.com/sipeed/picoclaw/pkg/routing"
+	"github.com/sipeed/picoclaw/pkg/session"
+	"github.com/sipeed/picoclaw/pkg/tools"
+)
+
+// AgentInstance represents a fully configured agent with its own workspace,
+// session manager, context builder, and tool registry.
+type AgentInstance struct {
+	ID             string
+	Name           string
+	Model          string
+	Fallbacks      []string
+	Workspace      string
+	MaxIterations  int
+	ContextWindow  int
+	Provider       providers.LLMProvider
+	Sessions       *session.SessionManager
+	ContextBuilder *ContextBuilder
+	Tools          *tools.ToolRegistry
+	Subagents      *config.SubagentsConfig
+	SkillsFilter   []string
+	Candidates     []providers.FallbackCandidate
+}
+
+// NewAgentInstance creates an agent instance from config.
+func NewAgentInstance(
+	agentCfg *config.AgentConfig,
+	defaults *config.AgentDefaults,
+	cfg *config.Config,
+	provider providers.LLMProvider,
+) *AgentInstance {
+	workspace := resolveAgentWorkspace(agentCfg, defaults)
+	os.MkdirAll(workspace, 0755)
+
+	model := resolveAgentModel(agentCfg, defaults)
+	fallbacks := resolveAgentFallbacks(agentCfg, defaults)
+
+	restrict := defaults.RestrictToWorkspace
+	toolsRegistry := tools.NewToolRegistry()
+	toolsRegistry.Register(tools.NewReadFileTool(workspace, restrict))
+	toolsRegistry.Register(tools.NewWriteFileTool(workspace, restrict))
+	toolsRegistry.Register(tools.NewListDirTool(workspace, restrict))
+	toolsRegistry.Register(tools.NewExecToolWithConfig(workspace, restrict, cfg))
+	toolsRegistry.Register(tools.NewEditFileTool(workspace, restrict))
+	toolsRegistry.Register(tools.NewAppendFileTool(workspace, restrict))
+
+	sessionsDir := filepath.Join(workspace, "sessions")
+	sessionsManager := session.NewSessionManager(sessionsDir)
+
+	contextBuilder := NewContextBuilder(workspace)
+	contextBuilder.SetToolsRegistry(toolsRegistry)
+
+	agentID := routing.DefaultAgentID
+	agentName := ""
+	var subagents *config.SubagentsConfig
+	var skillsFilter []string
+
+	if agentCfg != nil {
+		agentID = routing.NormalizeAgentID(agentCfg.ID)
+		agentName = agentCfg.Name
+		subagents = agentCfg.Subagents
+		skillsFilter = agentCfg.Skills
+	}
+
+	maxIter := defaults.MaxToolIterations
+	if maxIter == 0 {
+		maxIter = 20
+	}
+
+	// Resolve fallback candidates
+	modelCfg := providers.ModelConfig{
+		Primary:   model,
+		Fallbacks: fallbacks,
+	}
+	candidates := providers.ResolveCandidates(modelCfg, defaults.Provider)
+
+	return &AgentInstance{
+		ID:             agentID,
+		Name:           agentName,
+		Model:          model,
+		Fallbacks:      fallbacks,
+		Workspace:      workspace,
+		MaxIterations:  maxIter,
+		ContextWindow:  defaults.MaxTokens,
+		Provider:       provider,
+		Sessions:       sessionsManager,
+		ContextBuilder: contextBuilder,
+		Tools:          toolsRegistry,
+		Subagents:      subagents,
+		SkillsFilter:   skillsFilter,
+		Candidates:     candidates,
+	}
+}
+
+// resolveAgentWorkspace determines the workspace directory for an agent.
+func resolveAgentWorkspace(agentCfg *config.AgentConfig, defaults *config.AgentDefaults) string {
+	if agentCfg != nil && strings.TrimSpace(agentCfg.Workspace) != "" {
+		return expandHome(strings.TrimSpace(agentCfg.Workspace))
+	}
+	if agentCfg == nil || agentCfg.Default || agentCfg.ID == "" || routing.NormalizeAgentID(agentCfg.ID) == "main" {
+		return expandHome(defaults.Workspace)
+	}
+	home, _ := os.UserHomeDir()
+	id := routing.NormalizeAgentID(agentCfg.ID)
+	return filepath.Join(home, ".picoclaw", "workspace-"+id)
+}
+
+// resolveAgentModel resolves the primary model for an agent.
+func resolveAgentModel(agentCfg *config.AgentConfig, defaults *config.AgentDefaults) string {
+	if agentCfg != nil && agentCfg.Model != nil && strings.TrimSpace(agentCfg.Model.Primary) != "" {
+		return strings.TrimSpace(agentCfg.Model.Primary)
+	}
+	return defaults.Model
+}
+
+// resolveAgentFallbacks resolves the fallback models for an agent.
+func resolveAgentFallbacks(agentCfg *config.AgentConfig, defaults *config.AgentDefaults) []string {
+	if agentCfg != nil && agentCfg.Model != nil && agentCfg.Model.Fallbacks != nil {
+		return agentCfg.Model.Fallbacks
+	}
+	return defaults.ModelFallbacks
+}
+
+func expandHome(path string) string {
+	if path == "" {
+		return path
+	}
+	if path[0] == '~' {
+		home, _ := os.UserHomeDir()
+		if len(path) > 1 && path[1] == '/' {
+			return home + path[1:]
+		}
+		return home
+	}
+	return path
+}