package wfcompile

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

	"git-ssh.u1680832.nyat.app/weichen/Agent-Native.git/runtime/codeorch"
	"git-ssh.u1680832.nyat.app/weichen/Agent-Native.git/runtime/gates"
	agentllm "git-ssh.u1680832.nyat.app/weichen/Agent-Native.git/runtime/llm"
	"git-ssh.u1680832.nyat.app/weichen/Agent-Squad.git/squad"
	"git-ssh.u1680832.nyat.app/weichen/Agent-System-Backend.git/internal/tools"
	"git-ssh.u1680832.nyat.app/weichen/Agent-System-Backend.git/internal/workflow"
	core "git-ssh.u1680832.nyat.app/weichen/Agent-System-Core.git"
)

// Host 是编译图执行所需的宿主窄端口（结构性接口；runtime.RunCtx 天然满足，
// 避免 wfcompile 反向依赖 runtime 形成环）。
type Host interface {
	Context() context.Context
	Run() core.Run
	Settings() core.EffectiveSettings
	Emit(typ core.StreamEventType, payload any) error
	AskHITL(card core.HITLCard) (core.HITLResponse, error)
	UpdatePlan(p core.PlanSnapshot) error
	WriteArtifact(name, kind, mime string, content []byte) (core.Artifact, error)
	ExecuteTool(call core.ToolCallRequest) core.ToolCallResult
	CreateCard(card core.ActivityCard) (core.ActivityCard, error)
	ConversationSandbox() string
	Tools() []core.ToolDesc
}

// Spawner 可选子代理派发能力（脚本回调 agent.spawn 用）。
type Spawner interface {
	SpawnAgent(agentID, name, task, hint string) (core.AgentResultPayload, error)
	SpawnSubagent(name, task string, hint string) (core.AgentResultPayload, error)
}

// PlanGetter 可选当前计划读取（脚本回调 step 用）。
type PlanGetter interface {
	Plan() (core.PlanSnapshot, bool)
}

// Deps 是编译图执行的装配依赖。
type Deps struct {
	// DataDir 小队运行数据根（运行目录 = DataDir/wf/<runID>）。
	DataDir string
	// Backends 步骤后端解析器（WF1 期由调用方装配 agent-system；WP2 切 agent-native）。
	Backends *squad.BackendResolver
	// DefaultBackend 角色未声明后端时的缺省（空 = agent-system）。
	DefaultBackend string
	// JudgeStream 验收模型流（nil = 验证器不可用，判定 fail-closed 不通过）。
	JudgeStream agentllm.StreamFunc
	// ScriptTimeout 覆盖脚本墙钟超时（0 = 600s；上限 1800s 由 codeorch 持有）。
	ScriptTimeout time.Duration
}

// 脚本宿主限额（P4：回调 ≤50、单行 ≤1MB、超时 600/1800s）。
const (
	scriptDefaultTimeout = 600 * time.Second
	scriptMaxTimeout     = 1800 * time.Second
	scriptMaxCalls       = 50
	scriptMaxLine        = 1 << 20
	scriptModelPreview   = 4000
	// outFieldCap 宿主步产出回填黑板 out_<id> 字段的截断上限。
	outFieldCap = 2000
)

// hostRunner 宿主 intent 步执行器（squad.IntentRunner 实现）。
type hostRunner struct {
	rc      Host
	deps    Deps
	scripts map[string]string
	subOf   map[string]string

	mu       sync.Mutex
	verdicts map[string]string   // verdict 字段 → 最近一次判定
	fails    map[string]int      // verdict 字段 → 累计不通过次数（触顶即败）
	lastWhy  map[string]string   // 原步 ID → 最近一次不通过原因
	drops    []string            // 丢弃记录（legacy drops 同款 "stepID：why"）
	arts     []*core.ArtifactRef // 收集到的工件引用
}

func (r *hostRunner) Run(ctx context.Context, step squad.IntentStep) (*squad.ExecResult, error) {
	var content string
	var fields map[string]string
	var err error
	switch step.IntentID {
	case IntentHitl:
		content, fields, err = r.doHitl(step)
	case IntentTool:
		content, fields, err = r.doTool(ctx, step)
	case IntentArtifact:
		content, fields, err = r.doArtifact(step)
	case IntentCard:
		content, fields, err = r.doCard(step)
	case IntentScript:
		content, fields, err = r.doScript(ctx, step)
	case IntentCritic:
		content, fields, err = r.doCritic(ctx, step)
	default:
		err = fmt.Errorf("workflow: 未知宿主意图 %s", step.IntentID)
	}
	if err != nil {
		return &squad.ExecResult{Success: false, ErrorReason: err.Error()}, nil
	}
	patches := map[string][]byte{}
	main := "output.md"
	if len(step.Targets) > 0 {
		main = step.Targets[0]
	}
	// squad 交付物契约拒收空白文件（MaterializeTargets）；legacy 允许空产出，
	// 编译图用占位文本保持流转（out_ 字段仍按原始内容判空）。
	body := content
	if strings.TrimSpace(body) == "" {
		body = "（本步无文本产出）"
	}
	patches[main] = []byte(body + "\n")
	// 宿主步产出要点回填黑板（out_<step_id>），供后续步骤 TASK.md 快照引用。
	if fields == nil {
		fields = map[string]string{}
	}
	if sid := step.Slots["step_id"]; sid != "" && strings.TrimSpace(content) != "" {
		fields["out_"+sid] = truncate(content, outFieldCap)
	}
	// fields.json 是声明目标之一，恒写（空对象也写，避免交付物校验失败）。
	b, _ := json.Marshal(fields)
	patches["fields.json"] = b
	return &squad.ExecResult{Success: true, Patches: patches}, nil
}

// doHitl 人工问答步（legacy runWorkflowStep case "hitl" 同款）。
func (r *hostRunner) doHitl(step squad.IntentStep) (string, map[string]string, error) {
	kind := core.HITLKind(step.Slots["kind"])
	if kind == "" {
		kind = core.HITLKindInput
	}
	card := core.HITLCard{
		Question:       step.Slots["question"],
		Kind:           kind,
		AllowFreeInput: step.Slots["allow_free_input"] == "true",
		FreeInputHint:  step.Slots["free_input_hint"],
	}
	if raw := step.Slots["choices"]; strings.TrimSpace(raw) != "" {
		_ = json.Unmarshal([]byte(raw), &card.Choices)
	}
	resp, err := r.rc.AskHITL(card)
	if err != nil {
		return "", nil, err
	}
	if strings.TrimSpace(resp.FreeText) != "" {
		return strings.TrimSpace(resp.FreeText), nil, nil
	}
	return resp.ChoiceID, nil, nil
}

// doTool 宿主工具步（DeniedTools 已在编译期 Validate 拦截）。
func (r *hostRunner) doTool(_ context.Context, step squad.IntentStep) (string, map[string]string, error) {
	name := step.Slots["tool"]
	args := r.renderRefs(step.Slots["args"], step.WorkDir)
	res := r.rc.ExecuteTool(core.ToolCallRequest{Name: name, Arguments: json.RawMessage(args)})
	if res.Status == "error" {
		return "", nil, fmt.Errorf("workflow: 工具 %s 失败：%s", name, res.Output)
	}
	if res.Artifact != nil {
		r.track(&core.ArtifactRef{ArtifactID: res.Artifact.ID, Name: res.Artifact.Name, Kind: res.Artifact.Kind})
	}
	return res.Output, nil, nil
}

// doArtifact 工件步（空正文回退 content_ref 指向步骤的产出，legacy prev 语义）。
func (r *hostRunner) doArtifact(step squad.IntentStep) (string, map[string]string, error) {
	content := r.renderRefs(step.Slots["content"], step.WorkDir)
	if strings.TrimSpace(content) == "" {
		if ref := step.Slots["content_ref"]; ref != "" {
			content = r.readStepOutput(step.WorkDir, ref)
		}
	}
	name := step.Slots["name"]
	if strings.TrimSpace(name) == "" {
		name = step.Slots["step_id"] + ".md"
	}
	art, err := r.rc.WriteArtifact(name, "document", "text/markdown", []byte(content))
	if err != nil {
		return "", nil, err
	}
	r.track(&core.ArtifactRef{ArtifactID: art.ID, Name: art.Name, Kind: art.Kind})
	return string(art.ID), nil, nil
}

// doCard 收件箱卡步。
func (r *hostRunner) doCard(step squad.IntentStep) (string, map[string]string, error) {
	var tmpl core.ActivityCardTemplate
	if err := json.Unmarshal([]byte(step.Slots["template"]), &tmpl); err != nil {
		return "", nil, fmt.Errorf("workflow: 卡片模板不合法: %v", err)
	}
	card := core.ActivityCard{Title: tmpl.Title, Kind: tmpl.Kind, Tone: tmpl.Tone, Body: tmpl.Body, Actions: tmpl.Actions}
	if card.Kind == "" {
		card.Kind = core.CardKindResult
	}
	created, err := r.rc.CreateCard(card)
	if err != nil {
		return "", nil, err
	}
	return string(created.ID), nil, nil
}

// doScript 脚本步：插件脚本免确认；模型脚本（model=true）必须先过 HITL 确认；
// runtime.workflowScripts 开关默认关（P4）。执行走 codeorch 宿主（限额同款）。
func (r *hostRunner) doScript(ctx context.Context, step squad.IntentStep) (string, map[string]string, error) {
	path := step.Slots["path"]
	body := r.scripts[path]
	if strings.TrimSpace(body) == "" {
		return "", nil, fmt.Errorf("workflow: 脚本 %s 不在启动副本里", path)
	}
	if step.Slots["model"] == "true" {
		if !r.scriptsEnabled() {
			return "", nil, fmt.Errorf("workflow: 工作流脚本未开启")
		}
		preview := body
		if len(preview) > scriptModelPreview {
			preview = preview[:scriptModelPreview] + "\n…（脚本超长，已截断展示）"
		}
		resp, err := r.rc.AskHITL(core.HITLCard{
			Question: "运行这段脚本？\n" + preview, Kind: core.HITLKindConfirm, AllowFreeInput: false,
			Choices: []core.HITLChoice{
				{ID: "yes", Label: "运行", Description: "在会话沙箱里执行", Impact: "会调用工具并可能写入工件"},
				{ID: "no", Label: "取消", Description: "不执行", Impact: "不会改动任何东西"},
			},
		})
		if err != nil {
			return "", nil, err
		}
		if resp.ChoiceID != "yes" {
			return "未确认，未执行", nil, nil
		}
	}
	sandbox := strings.TrimSpace(r.rc.ConversationSandbox())
	if sandbox == "" {
		return "", nil, fmt.Errorf("workflow: 没有会话沙箱")
	}
	file, err := r.writeScriptFile(sandbox, "step-"+step.Slots["step_id"], body)
	if err != nil {
		return "", nil, err
	}
	return r.runScriptFile(ctx, sandbox, file)
}

func (r *hostRunner) scriptsEnabled() bool {
	return r.rc.Settings().GetBool("runtime.workflowScripts", false)
}

func (r *hostRunner) writeScriptFile(sandbox, prefix, body string) (string, error) {
	dir := filepath.Join(sandbox, ".agent")
	if err := os.MkdirAll(dir, 0o755); err != nil {
		return "", err
	}
	path := filepath.Join(dir, fmt.Sprintf("wf-%s-%d.py", prefix, time.Now().UnixNano()))
	if err := os.WriteFile(path, []byte(body), 0o600); err != nil {
		return "", err
	}
	return path, nil
}

// runScriptFile codeorch 宿主执行（legacy runScriptFile 同款限额与回调分发）。
func (r *hostRunner) runScriptFile(ctx context.Context, sandbox, path string) (string, map[string]string, error) {
	if !r.scriptsEnabled() {
		return "", nil, fmt.Errorf("workflow: 工作流脚本未开启")
	}
	timeout := r.deps.ScriptTimeout
	if timeout <= 0 {
		timeout = scriptDefaultTimeout
	}
	out := codeorch.RunFile(ctx, sandbox, path, codeorch.Limits{
		Timeout:        timeout,
		MaxTimeout:     scriptMaxTimeout,
		MaxCalls:       scriptMaxCalls,
		MaxResultBytes: scriptMaxLine,
		MaxModelChars:  16000,
		FullDir:        sandbox,
	}, func(c context.Context, dir, scriptPath string) (*exec.Cmd, error) {
		return tools.ScriptCommand(c, dir, scriptPath)
	}, func(_ context.Context, call codeorch.Call) (string, error) {
		output, got, err := r.dispatchScript(call)
		r.trackAll(got)
		return output, err
	})
	return out.ModelText(), nil, out.Err
}

// dispatchScript 脚本回调分发（legacy dispatchScript 同款语义与文案）。
func (r *hostRunner) dispatchScript(req codeorch.Call) (string, []*core.ArtifactRef, error) {
	switch req.Op {
	case "tool.call":
		if _, denied := workflow.DeniedTools[req.Name]; denied {
			return "", nil, fmt.Errorf("不能调用 %s", req.Name)
		}
		res := r.rc.ExecuteTool(core.ToolCallRequest{Name: req.Name, Arguments: req.Args})
		if res.Status == "error" {
			return "", nil, fmt.Errorf("%s", res.Output)
		}
		var arts []*core.ArtifactRef
		if res.Artifact != nil {
			arts = append(arts, &core.ArtifactRef{ArtifactID: res.Artifact.ID, Name: res.Artifact.Name, Kind: res.Artifact.Kind})
		}
		return res.Output, arts, nil
	case "hitl.ask":
		var choices []core.HITLChoice
		if len(req.Choices) > 0 {
			_ = json.Unmarshal(req.Choices, &choices)
		}
		card := core.HITLCard{Question: req.Question, Kind: core.HITLKindInput, AllowFreeInput: true}
		if len(choices) > 0 {
			card.Kind = core.HITLKindChoice
			card.AllowFreeInput = false
			card.Choices = choices
			for i := range card.Choices {
				if card.Choices[i].Impact == "" {
					card.Choices[i].Impact = "会按这个选择继续"
				}
			}
		}
		resp, err := r.rc.AskHITL(card)
		if err != nil {
			return "", nil, err
		}
		if strings.TrimSpace(resp.FreeText) != "" {
			return strings.TrimSpace(resp.FreeText), nil, nil
		}
		return resp.ChoiceID, nil, nil
	case "agent.spawn":
		sp, ok := r.rc.(Spawner)
		if !ok {
			return "", nil, fmt.Errorf("当前运行不能派发子代理")
		}
		agent := req.Agent
		if strings.TrimSpace(agent) == "" {
			agent = "general"
		}
		res, err := sp.SpawnAgent("agent.sub."+agent, req.Title, req.Task, "")
		if err != nil {
			return "", nil, err
		}
		text := res.Text
		if text == "" {
			text = res.Summary
		}
		return text, nil, nil
	case "artifact.register":
		name := req.Name
		if name == "" {
			name = "script.md"
		}
		art, err := r.rc.WriteArtifact(name, "document", "text/markdown", []byte(req.Content))
		if err != nil {
			return "", nil, err
		}
		return string(art.ID), []*core.ArtifactRef{{ArtifactID: art.ID, Name: art.Name, Kind: art.Kind}}, nil
	case "card.create":
		kind := core.CardKind(req.Kind)
		if kind == "" {
			kind = core.CardKindResult
		}
		title := req.Title
		if title == "" {
			title = req.Name
		}
		created, err := r.rc.CreateCard(core.ActivityCard{Title: title, Kind: kind})
		if err != nil {
			return "", nil, err
		}
		return string(created.ID), nil, nil
	case "step":
		r.applyScriptPlan(req.StepID, req.Title, req.Status)
		return req.Status, nil, nil
	default:
		return "", nil, fmt.Errorf("未知回调 %s", req.Op)
	}
}

// applyScriptPlan 脚本回调 step：更新右栏计划步态（legacy 同款）。
func (r *hostRunner) applyScriptPlan(id, title, status string) {
	switch status {
	case "pending", "in_progress", "done", "skipped":
	default:
		status = "done"
	}
	snap := core.PlanSnapshot{}
	if src, ok := r.rc.(PlanGetter); ok {
		if cur, found := src.Plan(); found {
			snap = cur
			snap.Steps = append([]core.PlanStep(nil), cur.Steps...)
		}
	}
	found := false
	for i := range snap.Steps {
		if snap.Steps[i].ID == id {
			snap.Steps[i].Status = status
			if title != "" {
				snap.Steps[i].Text = title
			}
			found = true
			break
		}
	}
	if !found {
		snap.Steps = append(snap.Steps, core.PlanStep{ID: id, Text: title, Status: status})
	}
	_ = r.rc.UpdatePlan(snap)
}

// doCritic 步骤验收（legacy judgeStep 同款提示词与 fail-closed 判定）：
// verdict 字段写 pass/fail 驱动 Loop 再武装；不通过记 drops 与原因。
func (r *hostRunner) doCritic(ctx context.Context, step squad.IntentStep) (string, map[string]string, error) {
	target := step.Slots["target_step"]
	field := step.Slots["verdict_field"]
	output := r.readStepOutput(step.WorkDir, target)
	verdict := r.judge(ctx, step.Slots["goal"], step.Slots["criteria"], output)
	fields := map[string]string{}
	if verdict.Passed {
		fields[field] = "pass"
		r.recordVerdict(field, target, "pass", "")
		return "验收通过。" + verdict.Reason, fields, nil
	}
	why := verdict.Reason
	if verdict.NextAction != "" {
		why += "。下一步：" + verdict.NextAction
	}
	fields[field] = "fail"
	fields["reason_"+target] = truncate(why, outFieldCap)
	fails := r.recordVerdict(field, target, "fail", why)
	// 评审预算耗尽仍不通过 = 步骤失败（legacy runStepWithCritic 同款语义；
	// Loop 触顶只停循环不失败，须由宿主判定 fail-closed）。
	if maxAtt := parseIntSlot(step.Slots["max_attempts"], 1); fails >= maxAtt {
		return "", nil, fmt.Errorf("步骤 %s 未通过验收：%s", target, why)
	}
	return "验收不通过：" + why, fields, nil
}

func parseIntSlot(s string, def int) int {
	n := 0
	if strings.TrimSpace(s) == "" {
		return def
	}
	for _, c := range s {
		if c < '0' || c > '9' {
			return def
		}
		n = n*10 + int(c-'0')
	}
	if n <= 0 {
		return def
	}
	return n
}

// recordVerdict 记录判定；返回该字段的累计不通过次数。
func (r *hostRunner) recordVerdict(field, target, verdict, why string) int {
	r.mu.Lock()
	defer r.mu.Unlock()
	if r.verdicts == nil {
		r.verdicts = map[string]string{}
		r.lastWhy = map[string]string{}
		r.fails = map[string]int{}
	}
	r.verdicts[field] = verdict
	if verdict != "pass" {
		r.lastWhy[target] = why
		r.drops = append(r.drops, target+"："+why)
		r.fails[field]++
		return r.fails[field]
	}
	return r.fails[field]
}

// judge 验收判定（legacy judgeStep 移植；JudgeStream 缺席 = 验证器不可用，
// 无法解析 = 不通过，均 fail-closed）。
func (r *hostRunner) judge(ctx context.Context, goal, criteria, output string) gates.Verdict {
	stream := r.deps.JudgeStream
	if stream == nil {
		return gates.Verdict{Passed: false, Reason: "验证器不可用", NextAction: "检查轻量模型配置"}
	}
	prompt := fmt.Sprintf("你是验收员。目标：%s\n验收标准：%s\n这一步的产出：\n%s\n标准里要求出现的句子，产出里必须逐字包含，否则 passed 必须为 false，nextAction 写出要补上的原句。只输出一个 JSON 对象，字段为 passed、reason、nextAction。", goal, criteria, output)
	var b strings.Builder
	for ev := range stream(ctx, "verify", []agentllm.Message{{Role: agentllm.RoleUser, Content: prompt}}, nil, agentllm.StreamOptions{}) {
		switch ev.Kind {
		case agentllm.KindTextDelta:
			b.WriteString(ev.Text)
		case agentllm.KindError:
			return gates.Verdict{Passed: false, Reason: "验证器不可用", NextAction: "稍后再试"}
		case agentllm.KindMessageEnd:
			if b.Len() == 0 {
				b.WriteString(ev.Message.Content)
			}
		}
	}
	verdict, err := gates.ParseVerdict(b.String())
	if err != nil {
		return gates.Verdict{Passed: false, Reason: "无法解析", NextAction: "按验收标准重做"}
	}
	return verdict
}

// readStepOutput 读取某步的主产出（相对本步子工作区回到运行根）。
func (r *hostRunner) readStepOutput(workDir, stepID string) string {
	sub, ok := r.subOf[stepID]
	if !ok {
		return ""
	}
	wsDir := filepath.Dir(filepath.Dir(workDir))
	data, err := os.ReadFile(filepath.Join(wsDir, filepath.FromSlash(sub), "output.md"))
	if err != nil {
		return ""
	}
	return string(data)
}

// renderRefs 运行期解析残留的 {{steps.X.output}} 占位符（宿主步实参/正文；
// workDir 为本步子工作区，经其上两级回到运行根再定位目标步产出）。
func (r *hostRunner) renderRefs(s, workDir string) string {
	if !strings.Contains(s, "{{steps.") {
		return s
	}
	var b strings.Builder
	for {
		i := strings.Index(s, "{{steps.")
		if i < 0 {
			b.WriteString(s)
			return b.String()
		}
		j := strings.Index(s[i:], "}}")
		if j < 0 {
			b.WriteString(s)
			return b.String()
		}
		token := s[i : i+j+2]
		id := strings.TrimSuffix(strings.TrimPrefix(token, "{{steps."), ".output}}")
		b.WriteString(s[:i])
		b.WriteString(r.readStepOutput(workDir, id))
		s = s[i+j+2:]
	}
}

func (r *hostRunner) track(art *core.ArtifactRef) {
	r.mu.Lock()
	r.arts = append(r.arts, art)
	r.mu.Unlock()
}

func (r *hostRunner) trackAll(arts []*core.ArtifactRef) {
	if len(arts) == 0 {
		return
	}
	r.mu.Lock()
	r.arts = append(r.arts, arts...)
	r.mu.Unlock()
}

func (r *hostRunner) snapshot() (arts []*core.ArtifactRef, drops []string, verdicts map[string]string, why map[string]string) {
	r.mu.Lock()
	defer r.mu.Unlock()
	arts = append([]*core.ArtifactRef(nil), r.arts...)
	drops = append([]string(nil), r.drops...)
	verdicts = map[string]string{}
	for k, v := range r.verdicts {
		verdicts[k] = v
	}
	why = map[string]string{}
	for k, v := range r.lastWhy {
		why[k] = v
	}
	return
}

func truncate(s string, n int) string {
	if len(s) <= n {
		return s
	}
	return s[:n] + "…（截断）"
}