Agent-Squad/squad/leader.go

package squad

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"time"

	"agent-native/exec"
)

// leaderExecRequest 构造 leader 轮次的执行请求：与标准步骤同等装配
// （过程事件桥、ToolProfile/Skills/工具白名单、执行标识与预算）——
// 修平此前 leader 轮丢弃 OnEvent 与 ToolProfile 的缺口。
func leaderExecRequest(drv *flowDriver, st *runState, leader RoleSpec, workDir, prompt, instructions string, targets []string, timeout time.Duration) exec.Request {
	stepID := fmt.Sprintf("leader_turn_%d", st.Leader.Turns)
	var budget *exec.Budget
	if timeout > 0 {
		budget = &exec.Budget{Deadline: time.Now().Add(timeout)}
	}
	return exec.Request{
		WorkDir:       workDir,
		Prompt:        prompt,
		Instructions:  instructions,
		Targets:       targets,
		Timeout:       timeout,
		ToolProfile:   orDefault(leader.ToolProfile, exec.ToolProfileWorkspace),
		ToolAllowlist: leader.Tools,
		Skills:        leader.Skills,
		SessionScope:  st.Meta.ID + "/" + stepID,
		ExecutionID:   st.Meta.ID + "-" + stepID,
		Budget:        budget,
		OnEvent: func(ev exec.ProcessEvent) {
			drv.emit(st, Event{Type: EvDetail, StepID: stepID, Role: leader.Role, Text: ev.Text,
				Data: marshalJSON(map[string]string{"process_type": ev.Type, "tool": ev.Tool, "detail": ev.Detail})})
		},
	}
}

// leader-delegation 模式（机制参考 Multica Squad Leader 协议，原创实现）：
// leader 是注册表中的普通角色，被引擎在每轮激活——读目标、按成员 skills
// 挑人、产出一份结构化委派决策（delegation.json），引擎按决策执行成员步骤、
// 把成员产出并回黑板、再唤醒 leader 评估下一步。leader 只协调不实现；
// 委派不了就升级问人；轮次有上限防失控。

// DefaultMaxLeaderTurns leader 模式每运行的 leader 轮次上限。
const DefaultMaxLeaderTurns = 8

// LeaderState leader 循环状态（workspace leader.json 持久化，重启可恢复）。
type LeaderState struct {
	Turns       int                `json:"turns"`
	MaxTurns    int                `json:"max_turns"`
	LeaderRole  string             `json:"leader_role"`
	Delegations []DelegationRecord `json:"delegations"`
}

// DelegationRecord 一次已执行的委派（历史注入下一轮 leader 上下文）。
type DelegationRecord struct {
	Turn    int      `json:"turn"`
	Member  string   `json:"member"`
	Title   string   `json:"title"`
	Targets []string `json:"targets,omitempty"`
	Status  string   `json:"status"` // completed / failed / degraded
	Error   string   `json:"error,omitempty"`
}

// delegation leader 单轮产出的结构化决策。
type delegation struct {
	Action   string   `json:"action"` // delegate | escalate | close | failed
	Member   string   `json:"member,omitempty"`
	Title    string   `json:"title,omitempty"`
	Targets  []string `json:"targets,omitempty"`
	Briefing string   `json:"briefing,omitempty"` // 给成员的补充指令
	Question string   `json:"question,omitempty"` // escalate 时的问题
	Reason   string   `json:"reason,omitempty"`
}

const leaderSubWorkspace = "tasks/00_leader"

func (st *runState) loadLeader() {
	if st.Leader != nil {
		return
	}
	st.Leader = &LeaderState{MaxTurns: DefaultMaxLeaderTurns}
	data, err := os.ReadFile(filepath.Join(st.Meta.WorkDir, "leader.json"))
	if err == nil {
		_ = json.Unmarshal(data, st.Leader)
	}
}

func (st *runState) saveLeader() {
	if st.Leader == nil {
		return
	}
	_ = writeJSON(filepath.Join(st.Meta.WorkDir, "leader.json"), st.Leader)
}

// leaderPrompt 组装 leader 的系统指令（协调契约 + 通用守则）。
func leaderPrompt(members []RoleSpec, catalogMd string) string {
	var b strings.Builder
	b.WriteString(`你是本小队的 LEADER。你被激活的唯一职责是协调，不是自己实现。

每轮你必须做且只做一件事：评估当前进展，然后输出一份委派决策文件 delegation.json 到本子目录（用工具写入，不要输出到对话里）：
{"action":"delegate","member":"成员role","title":"给成员的子任务标题","targets":["output.md"],"briefing":"给成员的补充指令/验收标准","reason":"为什么派给这个人"}
{"action":"escalate","question":"要向人提出的问题","reason":"为什么需要人拍板"}
{"action":"close","reason":"目标已达成，收口"}
{"action":"failed","reason":"无法达成的原因"}

硬规则：
1. 按成员的能力（skills/职责）挑人，不按头衔；没有合适成员就 escalate 说明缺口，而不是自己动手或乱派。
2. 一轮只委派一个子任务；子任务要小到可以一次完成并产出明确文件。
3. 委派的子任务标题里写清验收标准；不要复述目标全文。
4. 交付受阻时如实 escalate/failed，严禁假装完成或声称"基本完成"。
5. 所有成员子任务完成且交付物满足目标才 close；close 不等于人工终审。
6. 缺失的信息若会实质改变结果、执行路径、权限或安全，就 escalate 问人；否则自己决定并在 reason 里说明你决定了什么。

成员交付核实：每个成员完成后，其交付文件会自动快照到本目录 inbox/<步骤id>/ 下——请用工具查看该目录核实交付，不要凭空假设文件是否存在。

可用成员（role — 名称 — 技能 — 职责）：
`)
	for _, m := range members {
		fmt.Fprintf(&b, "- %s — %s — skills=%v — %v\n", m.Role, m.Name, m.Skills, m.Responsibilities)
	}
	if catalogMd != "" {
		b.WriteString("\n系统能力目录（供你判断哪些子任务不必派成员、以及该向用户收集什么信息；缺失必填信息时 escalate 并使用提问建议）：\n")
		b.WriteString(catalogMd)
	}
	return b.String()
}

// leaderTaskBrief 组装 leader 本轮的 TASK.md（目标 + 黑板 + 委派历史）。
func leaderTaskBrief(st *runState) string {
	var b strings.Builder
	b.WriteString("# Leader 轮次：评估并委派\n\n")
	fmt.Fprintf(&b, "## 运行目标\n%s\n\n", st.Meta.Goal.Text)
	if len(st.Clarifications) > 0 {
		b.WriteString("## 已澄清问答\n")
		for _, c := range st.Clarifications {
			fmt.Fprintf(&b, "- %s\n", c)
		}
		b.WriteString("\n")
	}
	if len(st.BB.Fields) > 0 {
		b.WriteString("## 黑板字段\n")
		for k, v := range st.BB.Fields {
			fmt.Fprintf(&b, "- %s = %s\n", k, v)
		}
		b.WriteString("\n")
	}
	if gaps := st.BB.UnresolvedBlockingGaps(); len(gaps) > 0 {
		b.WriteString("## 未解决缺口\n")
		for _, g := range gaps {
			fmt.Fprintf(&b, "- [%s] %s\n", g.ID, g.Item)
		}
		b.WriteString("\n")
	}
	if len(st.Leader.Delegations) > 0 {
		b.WriteString("## 委派历史\n")
		for _, d := range st.Leader.Delegations {
			fmt.Fprintf(&b, "- 第%d轮 → %s：%s（%s）\n", d.Turn, d.Member, d.Title, d.Status)
			if d.Error != "" {
				fmt.Fprintf(&b, "  - 错误：%s\n", d.Error)
			}
		}
		b.WriteString("\n")
	} else {
		b.WriteString("（尚无委派，这是第一轮。）\n\n")
	}
	b.WriteString("## 本轮产出要求\n\n写 delegation.json（结构见你的指令）到本子目录。\n")
	return b.String()
}

// runLeaderLoop leader-delegation 主循环：委派→执行→唤醒，直到
// close/failed/上限/挂起（escalation/gap/权限等由 HITL 处理后重入本函数）。
func (e *SquadEngine) runLeaderLoop(ctx context.Context, st *runState) (*RunResult, *hitlGate, error) {
	st.loadLeader()
	drv := &flowDriver{opts: e.deps}
	leader, ok := findAgent(st.Plan.Squad.Agents, st.Leader.LeaderRole)
	if !ok {
		if spec, exists := e.opts.Registry.Get(st.Leader.LeaderRole); exists {
			leader = spec
		} else {
			return &RunResult{RunID: st.Meta.ID, Status: RunFailed, Plan: planPtr(st),
				Error: "leader role not found: " + st.Leader.LeaderRole, WorkDir: st.Meta.WorkDir}, nil, nil
		}
	}
	var members []RoleSpec
	for _, a := range st.Plan.Squad.Agents {
		if a.Role != leader.Role {
			members = append(members, a)
		}
	}
	if len(members) == 0 {
		return &RunResult{RunID: st.Meta.ID, Status: RunFailed, Plan: planPtr(st),
			Error: "leader mode requires at least one member role besides the leader", WorkDir: st.Meta.WorkDir}, nil, nil
	}

	subDir := filepath.Join(st.Meta.WorkDir, filepath.FromSlash(leaderSubWorkspace))
	if err := os.MkdirAll(subDir, 0o755); err != nil {
		return nil, nil, err
	}
	_ = snapshotContextInto(st.Meta.WorkDir, subDir)

	for st.Leader.Turns < st.Leader.MaxTurns {
		// HITL：leader 角色权限升级（与标准模式同语义）。
		if leader.BashPermission == "ask" && !st.Approved["role:"+leader.Role] {
			if drv.policy(st).mode() != HitlInteractive {
				return &RunResult{RunID: st.Meta.ID, Status: RunFailed, Plan: planPtr(st),
					Error:   "leader role requires bash approval but hitl mode is " + string(drv.policy(st).mode()),
					WorkDir: st.Meta.WorkDir}, nil, nil
			}
			req := &HumanRequest{
				ID: newRequestID(), RunID: st.Meta.ID, Kind: HitlPermission, Severity: SeverityActionRequired,
				Question: fmt.Sprintf("leader 角色 %s 声明 bash_permission=ask，是否授权其在本次运行中使用更高权限？", leader.Name),
				Options: []HumanOption{
					{Value: "approve", Label: "授权本次运行"}, {Value: "reject", Label: "拒绝"}, {Value: "abort", Label: "中止"},
				},
				CreatedAt: time.Now(), Status: "pending",
			}
			gate := &hitlGate{Request: *req, PrevStatus: RunExecuting}
			if err := st.saveGate(gate); err == nil {
				st.Meta.Status = string(RunWaitingHuman)
				_ = st.save()
				drv.emitHuman(st, req)
			}
			return heldResult(st, gate), gate, nil
		}

		// 每轮重写 leader 上下文（黑板/委派历史已变化）。
		if err := os.WriteFile(filepath.Join(subDir, "TASK.md"), []byte(leaderTaskBrief(st)), 0o644); err != nil {
			return nil, nil, err
		}
		if err := os.WriteFile(filepath.Join(subDir, "AGENTS.md"), []byte(leaderPrompt(members, e.opts.IntentCatalog.intentCatalogMd())), 0o644); err != nil {
			return nil, nil, err
		}

		st.Leader.Turns++
		st.saveLeader()
		drv.emit(st, Event{Type: EvStepStarted, StepID: fmt.Sprintf("leader_turn_%d", st.Leader.Turns),
			Role: leader.Role, Text: "leader 评估并委派"})

		backend, backendName, err := e.deps.Backends.Resolve(leader, st.Meta.Backend)
		if err != nil {
			return e.leaderFail(st, err.Error()), nil, nil
		}
		prompt := readFileOr(filepath.Join(subDir, "TASK.md"), leaderTaskBrief(st))
		prompt = st.injectSteering(prompt)
		instructions := readFileOr(filepath.Join(subDir, "AGENTS.md"), leaderPrompt(members, e.opts.IntentCatalog.intentCatalogMd()))
		result, execErr := backend.Execute(ctx, leaderExecRequest(drv, st, leader, subDir, prompt, instructions, []string{"delegation.json"}, e.deps.StepTimeout))
		if execErr != nil || result == nil || !result.Success {
			reason := "leader execution failed"
			if execErr != nil {
				reason = execErr.Error()
			} else if result != nil && result.ErrorReason != "" {
				reason = result.ErrorReason
			}
			_ = os.Remove(filepath.Join(subDir, "delegation.json"))
			return e.leaderFail(st, fmt.Sprintf("leader turn %d: %s (backend=%s)", st.Leader.Turns, reason, backendName)), nil, nil
		}
		dec, perr := parseDelegation(subDir)
		if perr != nil {
			return e.leaderFail(st, fmt.Sprintf("leader turn %d: %v", st.Leader.Turns, perr)), nil, nil
		}
		_ = os.Remove(filepath.Join(subDir, "delegation.json")) // 每轮只消费一次

		switch dec.Action {
		case "close":
			drv.emit(st, Event{Type: EvStepCompleted, StepID: "leader_close", Role: leader.Role, Text: dec.Reason})
			st.saveLeader()
			out, gate, err := drv.finalize(ctx, st)
			if err != nil {
				return nil, nil, err
			}
			e.finalizeEvent(out)
			return out, gate, nil
		case "failed":
			return e.leaderFail(st, "leader 报告无法达成："+dec.Reason), nil, nil
		case "escalate":
			if drv.policy(st).mode() != HitlInteractive {
				return e.leaderFail(st, "leader 请求升级问人，但 hitl mode="+string(drv.policy(st).mode())), nil, nil
			}
			req := &HumanRequest{
				ID: newRequestID(), RunID: st.Meta.ID, Kind: HitlEscalation, Severity: SeverityActionRequired,
				StepID:   fmt.Sprintf("leader_turn_%d", st.Leader.Turns),
				Question: firstNonEmpty(dec.Question, "leader 需要人工拍板：") + "（原因：" + dec.Reason + "）",
				Options: []HumanOption{
					{Value: "continue", Label: "已在回答中给出决定，leader 继续"},
					{Value: "abort", Label: "中止运行"},
				},
				CreatedAt: time.Now(), Status: "pending",
			}
			gate := &hitlGate{Request: *req, PrevStatus: RunExecuting}
			if err := st.saveGate(gate); err == nil {
				st.Meta.Status = string(RunWaitingHuman)
				_ = st.save()
				drv.emitHuman(st, req)
			}
			return heldResult(st, gate), gate, nil
		case "delegate":
			member, ok := findAgent(members, dec.Member)
			if !ok {
				return e.leaderFail(st, fmt.Sprintf("leader 委派了编制外成员 %q", dec.Member)), nil, nil
			}
			step := StepSpec{
				ID:           fmt.Sprintf("m_%02d_%s", st.Leader.Turns, member.Role),
				Role:         member.Role,
				Title:        firstNonEmpty(dec.Title, "子任务"),
				SubWorkspace: fmt.Sprintf("tasks/%02d_%s", st.Leader.Turns, member.Role),
				Status:       "pending",
			}
			if len(dec.Targets) > 0 {
				step.Targets = dec.Targets
			} else {
				step.Targets = []string{"output.md"}
			}
			st.Plan.Workflow.Steps = append(st.Plan.Workflow.Steps, step)
			_ = st.save()

			// 构建成员子工作区并执行（复用标准驱动器单步执行）。
			idx := len(st.Plan.Workflow.Steps) - 1
			if err := e.ws.BuildSubWorkspaces(st.Meta.WorkDir, &st.Plan, &st.BB); err != nil {
				return nil, nil, err
			}
			memberBrief := readFileOr(filepath.Join(st.Meta.WorkDir, filepath.FromSlash(step.SubWorkspace), "TASK.md"), step.Title)
			if strings.TrimSpace(dec.Briefing) != "" {
				memberBrief += "\n\n## Leader 补充指令\n" + dec.Briefing
				_ = os.WriteFile(filepath.Join(st.Meta.WorkDir, filepath.FromSlash(step.SubWorkspace), "TASK.md"), []byte(memberBrief), 0o644)
			}
			out, gate, err := drv.runOneStep(ctx, st, idx)
			if err != nil {
				return nil, nil, err
			}
			rec := DelegationRecord{Turn: st.Leader.Turns, Member: member.Role, Title: step.Title,
				Targets: step.Targets, Status: "completed"}
			if out != nil { // 关键失败或挂起
				rec.Status = "failed"
				rec.Error = firstNonEmpty(out.Error, string(out.Status))
				st.Leader.Delegations = append(st.Leader.Delegations, rec)
				st.saveLeader()
				if out.Status == RunFailed {
					return out, nil, nil
				}
				return out, gate, nil // 挂起（gap/权限等），Respond 后重入循环
			}
			st.Leader.Delegations = append(st.Leader.Delegations, rec)
			st.saveLeader()
			// 成员交付快照进 leader inbox（leader 工具沙箱看不到成员目录，
			// 须物化到 leader 工作区才能自查交付——InputLayoutSnapshot 的对称应用）。
			snapshotDeliverablesToLeader(st, step)
			// 成员产出后检查阻塞缺口（等待条件挂起在标准 gap 通道上）。
			if g2 := drv.checkBlockingGaps(st); g2 != nil {
				return heldResult(st, g2), g2, nil
			}
			// 唤醒 leader：进入下一轮。
			continue
		default:
			return e.leaderFail(st, fmt.Sprintf("leader 输出了未知 action %q", dec.Action)), nil, nil
		}
	}
	return e.leaderFail(st, fmt.Sprintf("leader 轮次达上限 %d（防失控护栏），运行停止；可提高 MaxLeaderTurns 或人工介入", st.Leader.MaxTurns)), nil, nil
}

// leaderFail 统一的 leader 模式失败收口。
func (e *SquadEngine) leaderFail(st *runState, reason string) *RunResult {
	now := time.Now()
	st.Meta.Status = string(RunFailed)
	st.Meta.CompletedAt = &now
	wf := st.Workflow()
	wf.Status = "failed"
	st.setWorkflow(wf)
	_ = st.save()
	e.deps.Sink.Emit(Event{Type: EvRunFailed, RunID: st.Meta.ID, Text: reason, At: time.Now()})
	return &RunResult{RunID: st.Meta.ID, Status: RunFailed, Plan: planPtr(st),
		Error: reason, WorkDir: st.Meta.WorkDir, Usage: st.usageSnapshot()}
}

// snapshotDeliverablesToLeader 把成员交付文件复制进 leader 工作区 inbox/<步骤id>/。
func snapshotDeliverablesToLeader(st *runState, step StepSpec) {
	srcDir := filepath.Join(st.Meta.WorkDir, filepath.FromSlash(step.SubWorkspace))
	dstDir := filepath.Join(st.Meta.WorkDir, filepath.FromSlash(leaderSubWorkspace), "inbox", step.ID)
	for _, t := range step.Targets {
		data, err := os.ReadFile(filepath.Join(srcDir, filepath.FromSlash(t)))
		if err != nil || len(data) == 0 {
			continue
		}
		dst := filepath.Join(dstDir, filepath.Base(filepath.FromSlash(t)))
		_ = os.MkdirAll(filepath.Dir(dst), 0o755)
		_ = os.WriteFile(dst, data, 0o644)
	}
}

// parseDelegation 解析 leader 产出的 delegation.json。
func parseDelegation(subDir string) (*delegation, error) {
	data, err := os.ReadFile(filepath.Join(subDir, "delegation.json"))
	if err != nil {
		return nil, fmt.Errorf("leader 未产出 delegation.json: %w", err)
	}
	dec := &delegation{}
	if err := json.Unmarshal(data, dec); err != nil {
		return nil, fmt.Errorf("delegation.json 解析失败: %w", err)
	}
	if dec.Action == "" {
		return nil, fmt.Errorf("delegation.json 缺少 action")
	}
	return dec, nil
}