package workflow

import (
	"context"
	"encoding/json"
	"fmt"
	"html"
	"reflect"
	"regexp"
	"strconv"
	"strings"
	"time"

	"agent-desk/internal/ai"
	"agent-desk/internal/ai/runtime/graphs"
	"agent-desk/internal/ai/runtime/internal/impl/retrievers"
	"agent-desk/internal/ai/workflow/dsl"
	workflowregistry "agent-desk/internal/ai/workflow/registry"
	"agent-desk/internal/models"
	"agent-desk/internal/pkg/dto"
	"agent-desk/internal/pkg/dto/request"
	"agent-desk/internal/pkg/enums"
	"agent-desk/internal/pkg/utils"
	"agent-desk/internal/services"
)

const maxWorkflowSteps = 128

var workflowHTMLTagPattern = regexp.MustCompile(`<[^>]+>`)

type Input struct {
	Definition   dsl.Definition
	Conversation models.Conversation
	UserMessage  models.Message
	AIAgent      models.AIAgent
	AIConfig     models.AIConfig
}

type Result struct {
	Status           string
	ReplyText        string
	NodePath         []string
	NodeTraces       []NodeTrace
	PromptTokens     int
	CompletionTokens int
	RetrieverCount   int
	TraceData        string
	CheckPointID     string
	CheckPointData   string
	Interrupted      bool
	Interrupts       []InterruptSummary
}

type NodeTrace struct {
	NodeID        string
	NodeType      string
	Status        string
	InputPreview  string
	OutputPreview string
	ErrorMessage  string
	DurationMS    int
}

type InterruptSummary struct {
	Type        string
	ID          string
	InfoPreview string
}

type Executor struct{}

func NewExecutor() *Executor {
	return &Executor{}
}

type runState struct {
	input           Input
	nodesByID       map[string]dsl.Node
	outgoing        map[string][]dsl.Edge
	vars            map[string]map[string]any
	branchDecisions map[string]branchDecision
	result          Result
}

type workflowCheckPoint struct {
	Definition    dsl.Definition            `json:"definition"`
	ConfirmNodeID string                    `json:"confirmNodeId"`
	Vars          map[string]map[string]any `json:"vars"`
}

type branchDecision struct {
	SelectedEdgeID       string                `json:"selectedEdgeId,omitempty"`
	SelectedBranchID     string                `json:"selectedBranchId,omitempty"`
	SelectedBranchName   string                `json:"selectedBranchName,omitempty"`
	SelectedTargetNodeID string                `json:"selectedTargetNodeId,omitempty"`
	Reason               string                `json:"reason"`
	Evaluations          []conditionEvaluation `json:"evaluations,omitempty"`
}

type conditionEvaluation struct {
	EdgeID       string `json:"edgeId"`
	BranchID     string `json:"branchId,omitempty"`
	BranchName   string `json:"branchName,omitempty"`
	TargetNodeID string `json:"targetNodeId"`
	SourceNodeID string `json:"sourceNodeId,omitempty"`
	SourceField  string `json:"sourceField,omitempty"`
	Operator     string `json:"operator,omitempty"`
	LeftValue    any    `json:"leftValue,omitempty"`
	RightValue   any    `json:"rightValue,omitempty"`
	Matched      bool   `json:"matched"`
}

func (e *Executor) Execute(ctx context.Context, input Input) (*Result, error) {
	state := newRunState(input)
	currentID := strings.TrimSpace(input.Definition.EntryNodeID)
	if currentID == "" {
		return nil, fmt.Errorf("workflow entry node is required")
	}
	return e.executeFrom(ctx, state, currentID)
}

func (e *Executor) Resume(ctx context.Context, input Input, checkPointData string, resumeText string) (*Result, error) {
	var checkpoint workflowCheckPoint
	if err := json.Unmarshal([]byte(strings.TrimSpace(checkPointData)), &checkpoint); err != nil {
		return nil, fmt.Errorf("invalid workflow checkpoint: %w", err)
	}
	if len(checkpoint.Definition.Nodes) > 0 {
		input.Definition = checkpoint.Definition
	}
	state := newRunState(input)
	state.vars = checkpoint.Vars
	if state.vars == nil {
		state.vars = make(map[string]map[string]any)
	}
	confirmNodeID := strings.TrimSpace(checkpoint.ConfirmNodeID)
	if confirmNodeID == "" {
		return nil, fmt.Errorf("workflow checkpoint confirm node is required")
	}
	decision := graphs.ParseConfirmationDecision(resumeText)
	if decision == "" {
		node, ok := state.nodesByID[confirmNodeID]
		if !ok {
			return nil, fmt.Errorf("workflow node does not exist: %s", confirmNodeID)
		}
		if err := e.executeHumanConfirm(state, node); err != nil {
			return nil, err
		}
		state.result.Status = "interrupted"
		return &state.result, nil
	}
	state.setNodeVars(confirmNodeID, map[string]any{
		"confirmed":    decision == graphs.ConfirmationDecisionConfirm,
		"responseText": strings.TrimSpace(resumeText),
	})
	nextID, ok, err := state.nextNodeID(confirmNodeID)
	if err != nil {
		return nil, err
	}
	if !ok {
		state.result.Status = "completed"
		return &state.result, nil
	}
	return e.executeFrom(ctx, state, nextID)
}

func (e *Executor) executeFrom(ctx context.Context, state *runState, currentID string) (*Result, error) {
	for step := 0; step < maxWorkflowSteps; step++ {
		node, ok := state.nodesByID[currentID]
		if !ok {
			err := fmt.Errorf("workflow node does not exist: %s", currentID)
			state.result.Status = "error"
			return &state.result, err
		}
		state.result.NodePath = append(state.result.NodePath, node.ID)
		trace := NodeTrace{
			NodeID:       node.ID,
			NodeType:     node.Type,
			Status:       "running",
			InputPreview: workflowPreviewJSON(state.nodeInputPreview(node)),
		}
		startedAt := time.Now()
		if err := e.executeNode(ctx, state, node); err != nil {
			trace.Status = "failed"
			trace.ErrorMessage = err.Error()
			trace.DurationMS = int(time.Since(startedAt).Milliseconds())
			state.result.NodeTraces = append(state.result.NodeTraces, trace)
			state.result.Status = "error"
			return &state.result, err
		}
		trace.DurationMS = int(time.Since(startedAt).Milliseconds())
		if state.result.Interrupted {
			trace.OutputPreview = workflowPreviewJSON(state.nodeOutputPreview(node.ID))
			trace.Status = "interrupted"
			state.result.NodeTraces = append(state.result.NodeTraces, trace)
			state.result.Status = "interrupted"
			return &state.result, nil
		}
		if node.Type == workflowregistry.NodeTypeEnd {
			trace.OutputPreview = workflowPreviewJSON(state.nodeOutputPreview(node.ID))
			trace.Status = "completed"
			state.result.NodeTraces = append(state.result.NodeTraces, trace)
			state.result.Status = "completed"
			return &state.result, nil
		}
		nextID, ok, err := state.nextNodeID(node.ID)
		if err != nil {
			trace.OutputPreview = workflowPreviewJSON(state.nodeOutputPreview(node.ID))
			trace.Status = "failed"
			trace.ErrorMessage = err.Error()
			trace.DurationMS = int(time.Since(startedAt).Milliseconds())
			state.result.NodeTraces = append(state.result.NodeTraces, trace)
			state.result.Status = "error"
			return &state.result, err
		}
		trace.OutputPreview = workflowPreviewJSON(state.nodeOutputPreview(node.ID))
		trace.Status = "completed"
		state.result.NodeTraces = append(state.result.NodeTraces, trace)
		if !ok {
			state.result.Status = "completed"
			return &state.result, nil
		}
		currentID = nextID
	}
	err := fmt.Errorf("workflow exceeded max steps")
	state.result.Status = "error"
	return &state.result, err
}

func newRunState(input Input) *runState {
	state := &runState{
		input:           input,
		nodesByID:       make(map[string]dsl.Node, len(input.Definition.Nodes)),
		outgoing:        make(map[string][]dsl.Edge),
		vars:            make(map[string]map[string]any),
		branchDecisions: make(map[string]branchDecision),
		result: Result{
			Status:     "started",
			NodePath:   make([]string, 0),
			NodeTraces: make([]NodeTrace, 0),
		},
	}
	for _, node := range input.Definition.Nodes {
		node.ID = strings.TrimSpace(node.ID)
		node.Type = strings.TrimSpace(node.Type)
		if node.ID != "" {
			state.nodesByID[node.ID] = node
		}
	}
	for _, edge := range input.Definition.Edges {
		state.outgoing[edge.Source] = append(state.outgoing[edge.Source], edge)
	}
	return state
}

func (e *Executor) executeNode(ctx context.Context, state *runState, node dsl.Node) error {
	switch node.Type {
	case workflowregistry.NodeTypeStart:
		state.setNodeVars(node.ID, map[string]any{
			"conversationId":    state.input.Conversation.ID,
			"messageId":         state.input.UserMessage.ID,
			"aiAgentId":         state.input.AIAgent.ID,
			"userMessage":       strings.TrimSpace(state.input.UserMessage.Content),
			"knowledgeBaseIds":  utils.SplitInt64s(state.input.AIAgent.KnowledgeIDs),
			"conversationState": state.input.Conversation.Status,
		})
	case workflowregistry.NodeTypeConversationUnderstanding:
		return e.executeConversationUnderstanding(state, node)
	case workflowregistry.NodeTypeReplyPolicy:
		return e.executeReplyPolicy(state, node)
	case workflowregistry.NodeTypeKnowledgeRetrieve:
		return e.executeKnowledgeRetrieve(ctx, state, node)
	case workflowregistry.NodeTypeAnswerabilityGate:
		return e.executeAnswerabilityGate(state, node)
	case workflowregistry.NodeTypeCondition:
		state.setNodeVars(node.ID, map[string]any{"matched": true})
	case workflowregistry.NodeTypeAnalyzeConversation:
		return e.executeAnalyzeConversation(ctx, state, node)
	case workflowregistry.NodeTypePrepareTicketDraft:
		return e.executePrepareTicketDraft(ctx, state, node)
	case workflowregistry.NodeTypeHumanConfirm:
		return e.executeHumanConfirm(state, node)
	case workflowregistry.NodeTypeCreateTicket:
		return e.executeCreateTicket(state, node)
	case workflowregistry.NodeTypeLLMReply:
		return e.executeLLMReply(ctx, state, node)
	case workflowregistry.NodeTypeSendReply:
		replyText := strings.TrimSpace(toString(state.resolveInput(node, "replyText")))
		state.result.ReplyText = replyText
		state.setNodeVars(node.ID, map[string]any{
			"sent":           replyText != "",
			"replyMessageId": int64(0),
		})
	case workflowregistry.NodeTypeHandoffToHuman:
		return e.executeHandoffToHuman(state, node)
	case workflowregistry.NodeTypeEnd:
		state.setNodeVars(node.ID, map[string]any{"status": "completed"})
	default:
		return fmt.Errorf("unsupported workflow node type: %s", node.Type)
	}
	return nil
}

func (e *Executor) executeConversationUnderstanding(state *runState, node dsl.Node) error {
	rawMessage := strings.TrimSpace(toString(state.resolveInput(node, "userMessage")))
	if rawMessage == "" {
		rawMessage = state.input.UserMessage.Content
	}
	understanding := understandConversationMessage(rawMessage)
	state.setNodeVars(node.ID, map[string]any{
		"normalizedMessage": understanding.NormalizedMessage,
		"messageIntent":     understanding.MessageIntent,
		"answerScope":       understanding.AnswerScope,
		"confidence":        understanding.Confidence,
		"riskSignals":       understanding.RiskSignals,
		"reason":            understanding.Reason,
	})
	return nil
}

func (e *Executor) executeReplyPolicy(state *runState, node dsl.Node) error {
	intent := strings.TrimSpace(toString(state.resolveInput(node, "messageIntent")))
	scope := strings.TrimSpace(toString(state.resolveInput(node, "answerScope")))
	userMessage := normalizeWorkflowUserMessage(toString(state.resolveInput(node, "userMessage")))
	decision := decideWorkflowReplyPolicy(state.input.AIAgent, workflowReplyPolicyInput{
		MessageIntent: intent,
		AnswerScope:   scope,
		UserMessage:   userMessage,
		Answerability: strings.TrimSpace(toString(state.resolveInput(node, "answerability"))),
	})
	state.setNodeVars(node.ID, map[string]any{
		"action":           decision.Action,
		"replyText":        decision.ReplyText,
		"reason":           decision.Reason,
		"requiresFlow":     decision.RequiresFlow,
		"targetFlow":       decision.TargetFlow,
		"finalReplySource": decision.FinalReplySource,
	})
	return nil
}

func (e *Executor) executeCreateTicket(state *runState, node dsl.Node) error {
	confirmed := truthy(state.resolveInput(node, "confirmed"))
	if !confirmed {
		state.setNodeVars(node.ID, map[string]any{
			"ticketId": int64(0),
			"created":  false,
		})
		return nil
	}
	draft := asMap(state.resolveInput(node, "ticketDraft"))
	title := strings.TrimSpace(toString(draft["title"]))
	description := strings.TrimSpace(toString(draft["description"]))
	item, err := services.TicketService.CreateFromConversation(request.CreateTicketFromConversationRequest{
		ConversationID: state.input.Conversation.ID,
		Title:          title,
		Description:    description,
	}, workflowAIPrincipal(state.input.AIAgent))
	if err != nil {
		return err
	}
	state.setNodeVars(node.ID, map[string]any{
		"ticketId": item.ID,
		"ticketNo": item.TicketNo,
		"created":  true,
		"message":  buildTicketCreatedMessage(item),
	})
	return nil
}

func buildTicketCreatedMessage(item *models.Ticket) string {
	if item == nil {
		return "工单已创建。"
	}
	ticketNo := strings.TrimSpace(item.TicketNo)
	if ticketNo == "" {
		return fmt.Sprintf("工单已创建，工单 ID：%d。", item.ID)
	}
	return "工单已创建，工单号：" + ticketNo + "。"
}

func workflowAIPrincipal(aiAgent models.AIAgent) *dto.AuthPrincipal {
	username := strings.TrimSpace(aiAgent.Name)
	if username == "" {
		username = "AI"
	}
	return &dto.AuthPrincipal{
		UserID:   0,
		Username: username,
		Nickname: username,
	}
}

type workflowConversationUnderstanding struct {
	NormalizedMessage string
	MessageIntent     string
	AnswerScope       string
	Confidence        float64
	RiskSignals       []string
	Reason            string
}

type workflowReplyPolicyInput struct {
	MessageIntent string
	AnswerScope   string
	UserMessage   string
	Answerability string
}

type workflowReplyPolicyDecision struct {
	Action           string
	ReplyText        string
	Reason           string
	RequiresFlow     bool
	TargetFlow       string
	FinalReplySource string
}

func understandConversationMessage(rawMessage string) workflowConversationUnderstanding {
	message := normalizeWorkflowUserMessage(rawMessage)
	ret := workflowConversationUnderstanding{
		NormalizedMessage: message,
		MessageIntent:     "unknown",
		AnswerScope:       "needs_clarification",
		Confidence:        0.5,
		Reason:            "message intent is unclear",
	}
	if message == "" {
		ret.MessageIntent = "unknown"
		ret.AnswerScope = "needs_clarification"
		ret.Confidence = 0.9
		ret.Reason = "empty message"
		return ret
	}
	lower := strings.ToLower(message)
	switch {
	case isGreetingMessage(lower):
		ret.MessageIntent = "greeting"
		ret.AnswerScope = "direct_reply"
		ret.Confidence = 0.98
		ret.Reason = "matched greeting phrase"
	case containsAnyWorkflowText(lower, "谢谢", "感谢", "多谢", "辛苦了", "thank"):
		ret.MessageIntent = "thanks"
		ret.AnswerScope = "direct_reply"
		ret.Confidence = 0.95
		ret.Reason = "matched thanks phrase"
	case containsAnyWorkflowText(lower, "再见", "拜拜", "不用了", "没事了", "结束"):
		ret.MessageIntent = "end_conversation"
		ret.AnswerScope = "direct_reply"
		ret.Confidence = 0.9
		ret.Reason = "matched ending phrase"
	case containsAnyWorkflowText(lower, "人工", "转人工", "真人", "客服"):
		ret.MessageIntent = "handoff_request"
		ret.AnswerScope = "needs_handoff"
		ret.Confidence = 0.95
		ret.RiskSignals = append(ret.RiskSignals, "handoff_requested")
		ret.Reason = "matched handoff phrase"
	case containsAnyWorkflowText(lower, "投诉", "举报", "差评", "曝光", "起诉", "律师", "12315"):
		ret.MessageIntent = "complaint"
		ret.AnswerScope = "needs_handoff"
		ret.Confidence = 0.92
		ret.RiskSignals = append(ret.RiskSignals, "complaint_escalation")
		ret.Reason = "matched complaint phrase"
	case containsAnyWorkflowText(lower, "工单", "报障", "售后", "登记问题", "记录问题"):
		ret.MessageIntent = "ticket_request"
		ret.AnswerScope = "needs_ticket"
		ret.Confidence = 0.9
		ret.RiskSignals = append(ret.RiskSignals, "ticket_expected")
		ret.Reason = "matched ticket phrase"
	case containsAnyWorkflowText(lower, "确认", "可以", "好的", "好", "是的", "取消"):
		ret.MessageIntent = "confirmation"
		ret.AnswerScope = "direct_reply"
		ret.Confidence = 0.8
		ret.Reason = "matched confirmation phrase"
	case isAmbiguousWorkflowQuestion(lower):
		ret.MessageIntent = "ambiguous_question"
		ret.AnswerScope = "needs_clarification"
		ret.Confidence = 0.82
		ret.Reason = "message lacks a concrete business object"
	default:
		ret.MessageIntent = "business_question"
		ret.AnswerScope = "needs_knowledge"
		ret.Confidence = 0.7
		ret.Reason = "default business question policy"
	}
	return ret
}

func decideWorkflowReplyPolicy(aiAgent models.AIAgent, input workflowReplyPolicyInput) workflowReplyPolicyDecision {
	intent := strings.TrimSpace(input.MessageIntent)
	scope := strings.TrimSpace(input.AnswerScope)
	if answerability := strings.TrimSpace(input.Answerability); answerability != "" && answerability != "answerable" {
		return workflowReplyPolicyDecision{
			Action:           "knowledge_fallback",
			ReplyText:        workflowKnowledgeFallbackReply(aiAgent),
			Reason:           "knowledge is not sufficient for business answer",
			FinalReplySource: "knowledge_fallback",
		}
	}
	switch {
	case intent == "greeting":
		return workflowReplyPolicyDecision{Action: "direct_reply", ReplyText: "您好，请问有什么可以帮您？", Reason: "greeting can be answered directly", FinalReplySource: "direct_reply"}
	case intent == "thanks":
		return workflowReplyPolicyDecision{Action: "direct_reply", ReplyText: "不客气，如有其他问题可以继续告诉我。", Reason: "thanks can be answered directly", FinalReplySource: "direct_reply"}
	case intent == "end_conversation":
		return workflowReplyPolicyDecision{Action: "end_conversation", ReplyText: "好的，如后续还有问题可以随时联系。", Reason: "conversation ending phrase", FinalReplySource: "direct_reply"}
	case intent == "confirmation":
		return workflowReplyPolicyDecision{Action: "direct_reply", ReplyText: "好的，请继续补充需要处理的问题。", Reason: "confirmation without pending interrupt", FinalReplySource: "direct_reply"}
	case intent == "handoff_request" || scope == "needs_handoff":
		return workflowReplyPolicyDecision{Action: "handoff_to_human", Reason: "user requested human support or risk requires handoff", RequiresFlow: true, TargetFlow: "handoff_to_human", FinalReplySource: "handoff_notice"}
	case intent == "ticket_request" || scope == "needs_ticket":
		return workflowReplyPolicyDecision{Action: "prepare_ticket", Reason: "user requested ticket handling", RequiresFlow: true, TargetFlow: "prepare_ticket", FinalReplySource: "ticket_result"}
	case intent == "ambiguous_question" || scope == "needs_clarification":
		return workflowReplyPolicyDecision{Action: "clarify", ReplyText: "请补充具体的产品、场景、报错信息或你希望处理的结果，我再继续帮你确认。", Reason: "message needs clarification", FinalReplySource: "clarification"}
	case scope == "needs_knowledge":
		return workflowReplyPolicyDecision{Action: "retrieve_knowledge", Reason: "business question should be answered with knowledge evidence", RequiresFlow: true, TargetFlow: "knowledge", FinalReplySource: "knowledge_answer"}
	default:
		return workflowReplyPolicyDecision{Action: "clarify", ReplyText: "请补充更具体的问题，我再继续帮你处理。", Reason: "fallback to clarification for unclear policy input", FinalReplySource: "clarification"}
	}
}

func normalizeWorkflowUserMessage(value string) string {
	value = strings.TrimSpace(value)
	if value == "" {
		return ""
	}
	value = workflowHTMLTagPattern.ReplaceAllString(value, " ")
	value = html.UnescapeString(value)
	value = strings.Join(strings.Fields(value), " ")
	return strings.TrimSpace(value)
}

func isGreetingMessage(value string) bool {
	trimmed := strings.Trim(value, " 	\r\n。.!！?？~～")
	return containsAnyWorkflowText(trimmed, "你好", "您好", "在吗", "在不在") || trimmed == "hello" || trimmed == "hi"
}

func isAmbiguousWorkflowQuestion(value string) bool {
	trimmed := strings.Trim(value, " 	\r\n。.!！?？~～")
	return containsAnyWorkflowText(trimmed, "怎么弄", "怎么办", "怎么处理", "帮我看看", "有问题") || len([]rune(trimmed)) <= 3
}

func containsAnyWorkflowText(value string, needles ...string) bool {
	for _, needle := range needles {
		if strings.Contains(value, needle) {
			return true
		}
	}
	return false
}

func (e *Executor) executeHumanConfirm(state *runState, node dsl.Node) error {
	prompt := strings.TrimSpace(toString(state.resolveInput(node, "prompt")))
	if prompt == "" {
		prompt = "请确认是否继续。"
	}
	infoPreview, err := json.Marshal(map[string]string{"message": prompt})
	if err != nil {
		return err
	}
	state.result.Interrupted = true
	state.result.CheckPointID = buildWorkflowCheckPointID(state.input, node.ID)
	checkpoint, err := json.Marshal(workflowCheckPoint{
		Definition:    state.input.Definition,
		ConfirmNodeID: node.ID,
		Vars:          state.vars,
	})
	if err != nil {
		return err
	}
	state.result.CheckPointData = string(checkpoint)
	state.result.Interrupts = []InterruptSummary{
		{
			Type:        workflowregistry.NodeTypeHumanConfirm,
			ID:          node.ID,
			InfoPreview: string(infoPreview),
		},
	}
	return nil
}

func buildWorkflowCheckPointID(input Input, nodeID string) string {
	return fmt.Sprintf("workflow:%d:%d:%s", input.Conversation.ID, input.UserMessage.ID, strings.TrimSpace(nodeID))
}

func (e *Executor) executePrepareTicketDraft(ctx context.Context, state *runState, node dsl.Node) error {
	issue := strings.TrimSpace(toString(state.resolveInput(node, "issue")))
	input := graphs.PrepareTicketDraftInput{
		Issue: issue,
	}
	if title := strings.TrimSpace(readStringConfig(node.Config, "title")); title != "" {
		input.Title = title
	}
	if description := strings.TrimSpace(readStringConfig(node.Config, "description")); description != "" {
		input.Description = description
	}
	if impact := strings.TrimSpace(readStringConfig(node.Config, "impact")); impact != "" {
		input.Impact = impact
	}
	if expectedOutcome := strings.TrimSpace(readStringConfig(node.Config, "expectedOutcome")); expectedOutcome != "" {
		input.ExpectedOutcome = expectedOutcome
	}
	if currentAttempt := strings.TrimSpace(readStringConfig(node.Config, "currentAttempt")); currentAttempt != "" {
		input.CurrentAttempt = currentAttempt
	}
	args, err := json.Marshal(input)
	if err != nil {
		return err
	}
	raw, err := graphs.NewPrepareTicketDraftGraph(state.input.Conversation).Run(ctx, string(args))
	if err != nil {
		return err
	}
	var result graphs.PrepareTicketDraftResult
	if err := json.Unmarshal([]byte(raw), &result); err != nil {
		return err
	}
	state.setNodeVars(node.ID, map[string]any{
		"ticketDraft": map[string]any{
			"ready":             result.Ready,
			"title":             strings.TrimSpace(result.Title),
			"description":       strings.TrimSpace(result.Description),
			"missingFields":     result.MissingFields,
			"followUpQuestions": result.FollowUpQuestions,
			"conversationFacts": result.ConversationFacts,
		},
	})
	return nil
}

func (e *Executor) executeAnalyzeConversation(ctx context.Context, state *runState, node dsl.Node) error {
	userMessage := strings.TrimSpace(toString(state.resolveInput(node, "userMessage")))
	input := graphs.AnalyzeConversationInput{
		ObservedIssue: userMessage,
	}
	if strings.TrimSpace(readStringConfig(node.Config, "goal")) != "" {
		input.Goal = strings.TrimSpace(readStringConfig(node.Config, "goal"))
	}
	if readBoolConfig(node.Config, "needTicket") {
		input.NeedTicket = true
	}
	if readBoolConfig(node.Config, "needHumanHandoff") {
		input.NeedHumanHandoff = true
	}
	if readBoolConfig(node.Config, "needQualityCheck") {
		input.NeedQualityCheck = true
	}
	if strings.TrimSpace(readStringConfig(node.Config, "additionalContext")) != "" {
		input.AdditionalContext = strings.TrimSpace(readStringConfig(node.Config, "additionalContext"))
	}
	args, err := json.Marshal(input)
	if err != nil {
		return err
	}
	raw, err := graphs.NewAnalyzeConversationGraph(state.input.Conversation).Run(ctx, string(args))
	if err != nil {
		return err
	}
	var result graphs.AnalyzeConversationResult
	if err := json.Unmarshal([]byte(raw), &result); err != nil {
		return err
	}
	nextAction := strings.TrimSpace(result.RecommendedNextAction)
	state.setNodeVars(node.ID, map[string]any{
		"intent":           strings.TrimSpace(result.UserIntent),
		"riskLevel":        strings.TrimSpace(result.RiskLevel),
		"needTicket":       nextAction == "prepare_ticket",
		"needHumanHandoff": nextAction == "handoff_to_human",
	})
	return nil
}

func (e *Executor) executeHandoffToHuman(state *runState, node dsl.Node) error {
	if _, hasConfirmedInput := node.Inputs["confirmed"]; hasConfirmedInput && !truthy(state.resolveInput(node, "confirmed")) {
		state.setNodeVars(node.ID, map[string]any{
			"handoffId":  int64(0),
			"reason":     strings.TrimSpace(toString(state.resolveInput(node, "reason"))),
			"decision":   "cancelled",
			"teamId":     int64(0),
			"assigneeId": int64(0),
			"message":    "",
			"skipped":    true,
		})
		return nil
	}
	reason := strings.TrimSpace(toString(state.resolveInput(node, "reason")))
	result, err := services.ConversationHumanDispatchService.HandoffByAIWithRequestID(
		state.input.Conversation.ID,
		state.input.AIAgent,
		reason,
		strings.TrimSpace(state.input.UserMessage.RequestID),
	)
	if err != nil {
		return err
	}
	output := map[string]any{
		"handoffId":  int64(0),
		"reason":     reason,
		"decision":   "",
		"teamId":     int64(0),
		"assigneeId": int64(0),
		"message":    "",
	}
	if result != nil {
		output["decision"] = string(result.Decision)
		output["teamId"] = result.TeamID
		output["assigneeId"] = result.AssigneeID
		output["message"] = strings.TrimSpace(result.Message)
	}
	state.setNodeVars(node.ID, output)
	return nil
}

func (e *Executor) executeKnowledgeRetrieve(ctx context.Context, state *runState, node dsl.Node) error {
	query := strings.TrimSpace(toString(state.resolveInput(node, "query")))
	retriever := retrievers.NewKnowledgeRetriever(state.input.AIAgent)
	result, err := retriever.RetrieveContext(ctx, query)
	if err != nil {
		return err
	}
	items := make([]map[string]any, 0, len(result.ContextResults))
	for _, item := range result.ContextResults {
		items = append(items, map[string]any{
			"knowledgeBaseId": item.KnowledgeBaseID,
			"documentId":      item.DocumentID,
			"chunkId":         item.ChunkID,
			"content":         item.Content,
			"score":           item.Score,
		})
	}
	state.result.RetrieverCount = len(result.Hits)
	state.setNodeVars(node.ID, map[string]any{
		"items":   items,
		"summary": result.ContextText,
	})
	return nil
}

func (e *Executor) executeAnswerabilityGate(state *runState, node dsl.Node) error {
	items := state.resolveInput(node, "knowledgeItems")
	answerability := "unanswerable"
	reason := "no retrieved knowledge items"
	if hasItems(items) {
		answerability = "answerable"
		reason = "retrieved knowledge items are available"
	}
	state.setNodeVars(node.ID, map[string]any{
		"answerability": answerability,
		"reason":        reason,
	})
	return nil
}

func (e *Executor) executeLLMReply(ctx context.Context, state *runState, node dsl.Node) error {
	if staticReply := strings.TrimSpace(readStringConfig(node.Config, "staticReply")); staticReply != "" {
		state.setNodeVars(node.ID, map[string]any{"replyText": staticReply})
		return nil
	}
	userPrompt := strings.TrimSpace(toString(state.resolveInput(node, "userMessage")))
	if userPrompt == "" {
		userPrompt = strings.TrimSpace(state.input.UserMessage.Content)
	}
	knowledgeItems := toString(state.resolveInput(node, "knowledgeItems"))
	systemPrompt := strings.TrimSpace(state.input.AIAgent.SystemPrompt)
	if prompt := strings.TrimSpace(readStringConfig(node.Config, "prompt")); prompt != "" {
		systemPrompt = strings.TrimSpace(systemPrompt + "\n\n" + prompt)
	}
	if _, declaresKnowledge := node.Inputs["knowledgeItems"]; declaresKnowledge && len(utils.SplitInt64s(state.input.AIAgent.KnowledgeIDs)) > 0 && !hasItems(state.resolveInput(node, "knowledgeItems")) {
		state.setNodeVars(node.ID, map[string]any{"replyText": workflowKnowledgeFallbackReply(state.input.AIAgent)})
		return nil
	}
	if knowledgeItems != "" {
		userPrompt = userPrompt + "\n\nKnowledge context:\n" + knowledgeItems
	}
	result, err := ai.LLM.ChatWithConfig(ctx, state.input.AIConfig, systemPrompt, userPrompt)
	if err != nil {
		return err
	}
	state.result.PromptTokens += result.PromptTokens
	state.result.CompletionTokens += result.CompletionTokens
	state.setNodeVars(node.ID, map[string]any{"replyText": result.Content})
	return nil
}

func workflowKnowledgeFallbackReply(aiAgent models.AIAgent) string {
	if reply := strings.TrimSpace(aiAgent.FallbackMessage); reply != "" {
		return reply
	}
	if aiAgent.FallbackMode == enums.AIAgentFallbackModeSuggestRetry {
		return "当前知识库里没有找到足够明确的信息，你可以换个更具体的问法再试一次。"
	}
	return "当前知识库暂无明确信息。"
}

func (s *runState) nextNodeID(sourceNodeID string) (string, bool, error) {
	edges := s.outgoing[sourceNodeID]
	if len(edges) == 0 {
		return "", false, nil
	}
	node := s.nodesByID[sourceNodeID]
	if strings.TrimSpace(node.Type) != workflowregistry.NodeTypeCondition {
		return strings.TrimSpace(edges[0].Target), true, nil
	}
	config := dsl.ConditionConfig{}
	if len(node.Config) > 0 {
		if err := json.Unmarshal(node.Config, &config); err != nil {
			return "", false, fmt.Errorf("invalid condition node config: %w", err)
		}
	}
	evaluations := make([]conditionEvaluation, 0)
	for _, branch := range config.Branches {
		if branch.Default {
			continue
		}
		matched, evaluation, err := s.evaluateConditionBranch(sourceNodeID, branch)
		if err != nil {
			return "", false, err
		}
		evaluations = append(evaluations, evaluation)
		if matched {
			targetNodeID := strings.TrimSpace(branch.TargetNodeID)
			s.branchDecisions[sourceNodeID] = branchDecision{
				SelectedEdgeID:       s.edgeIDForTarget(sourceNodeID, targetNodeID),
				SelectedBranchID:     strings.TrimSpace(branch.ID),
				SelectedBranchName:   strings.TrimSpace(branch.Name),
				SelectedTargetNodeID: targetNodeID,
				Reason:               "condition branch matched",
				Evaluations:          evaluations,
			}
			return targetNodeID, true, nil
		}
	}
	for _, branch := range config.Branches {
		if !branch.Default {
			continue
		}
		targetNodeID := strings.TrimSpace(branch.TargetNodeID)
		s.branchDecisions[sourceNodeID] = branchDecision{
			SelectedEdgeID:       s.edgeIDForTarget(sourceNodeID, targetNodeID),
			SelectedBranchID:     strings.TrimSpace(branch.ID),
			SelectedBranchName:   strings.TrimSpace(branch.Name),
			SelectedTargetNodeID: targetNodeID,
			Reason:               "no condition branch matched; selected default branch",
			Evaluations:          evaluations,
		}
		return targetNodeID, true, nil
	}
	s.branchDecisions[sourceNodeID] = branchDecision{
		Reason:      "no condition branch matched and no default branch exists",
		Evaluations: evaluations,
	}
	return "", false, nil
}

func (s *runState) evaluateConditionBranch(sourceNodeID string, branch dsl.ConditionBranch) (bool, conditionEvaluation, error) {
	condition := branch.Condition
	targetNodeID := strings.TrimSpace(branch.TargetNodeID)
	evaluation := conditionEvaluation{
		EdgeID:       s.edgeIDForTarget(sourceNodeID, targetNodeID),
		BranchID:     strings.TrimSpace(branch.ID),
		BranchName:   strings.TrimSpace(branch.Name),
		TargetNodeID: targetNodeID,
	}
	if condition == nil {
		evaluation.Matched = true
		return true, evaluation, nil
	}
	left := s.resolveSelector(condition.Left)
	operator := strings.TrimSpace(condition.Operator)
	if condition.Left != nil {
		evaluation.SourceNodeID = strings.TrimSpace(condition.Left.NodeID)
		evaluation.SourceField = strings.TrimSpace(condition.Left.Field)
	}
	evaluation.Operator = operator
	evaluation.LeftValue = left
	evaluation.RightValue = condition.Right
	if operator == "" && strings.TrimSpace(condition.Expression) != "" {
		return false, evaluation, fmt.Errorf("free-form workflow condition expressions are not supported")
	}
	var matched bool
	switch operator {
	case "eq", "equals":
		matched = compareString(left, condition.Right) == 0
	case "neq", "not_equals":
		matched = compareString(left, condition.Right) != 0
	case "contains":
		matched = strings.Contains(toString(left), toString(condition.Right))
	case "exists":
		matched = exists(left)
	case "not_exists":
		matched = !exists(left)
	case "truthy", "is_true":
		matched = truthy(left)
	case "falsy", "is_false":
		matched = !truthy(left)
	case "gt":
		matched = compareNumber(left, condition.Right) > 0
	case "gte":
		matched = compareNumber(left, condition.Right) >= 0
	case "lt":
		matched = compareNumber(left, condition.Right) < 0
	case "lte":
		matched = compareNumber(left, condition.Right) <= 0
	default:
		return false, evaluation, fmt.Errorf("unsupported workflow condition operator: %s", operator)
	}
	evaluation.Matched = matched
	return matched, evaluation, nil
}

func (s *runState) edgeIDForTarget(sourceNodeID string, targetNodeID string) string {
	for _, edge := range s.outgoing[sourceNodeID] {
		if strings.TrimSpace(edge.Target) == targetNodeID {
			return strings.TrimSpace(edge.ID)
		}
	}
	return ""
}

func (s *runState) setNodeVars(nodeID string, values map[string]any) {
	s.vars[nodeID] = values
}

func (s *runState) resolveInput(node dsl.Node, inputName string) any {
	selector, ok := node.Inputs[inputName]
	if !ok {
		return nil
	}
	return s.resolveSelector(&selector)
}

func (s *runState) nodeInputPreview(node dsl.Node) map[string]any {
	inputs := make(map[string]any, len(node.Inputs))
	for name, selector := range node.Inputs {
		inputs[name] = s.resolveSelector(&selector)
	}
	ret := map[string]any{
		"inputs": inputs,
	}
	if len(node.Config) > 0 {
		var cfg any
		if err := json.Unmarshal(node.Config, &cfg); err == nil {
			ret["config"] = cfg
		} else {
			ret["config"] = string(node.Config)
		}
	}
	return ret
}

func (s *runState) nodeOutputPreview(nodeID string) map[string]any {
	ret := map[string]any{
		"outputs": s.vars[nodeID],
	}
	if decision, ok := s.branchDecisions[nodeID]; ok {
		ret["branchDecision"] = decision
	}
	return ret
}

func workflowPreviewJSON(value any) string {
	raw, err := json.Marshal(value)
	if err != nil {
		return ""
	}
	const maxPreviewBytes = 2000
	if len(raw) <= maxPreviewBytes {
		return string(raw)
	}
	return string(raw[:maxPreviewBytes])
}

func (s *runState) resolveSelector(selector *dsl.VariableSelector) any {
	if selector == nil {
		return nil
	}
	fields := s.vars[strings.TrimSpace(selector.NodeID)]
	if fields == nil {
		return nil
	}
	return fields[strings.TrimSpace(selector.Field)]
}

func readStringConfig(raw json.RawMessage, key string) string {
	if len(raw) == 0 {
		return ""
	}
	var cfg map[string]any
	if err := json.Unmarshal(raw, &cfg); err != nil {
		return ""
	}
	return toString(cfg[key])
}

func readBoolConfig(raw json.RawMessage, key string) bool {
	if len(raw) == 0 {
		return false
	}
	var cfg map[string]any
	if err := json.Unmarshal(raw, &cfg); err != nil {
		return false
	}
	return truthy(cfg[key])
}

func compareString(left any, right any) int {
	return strings.Compare(toString(left), toString(right))
}

func compareNumber(left any, right any) int {
	leftNum := toFloat(left)
	rightNum := toFloat(right)
	switch {
	case leftNum > rightNum:
		return 1
	case leftNum < rightNum:
		return -1
	default:
		return 0
	}
}

func toString(value any) string {
	switch v := value.(type) {
	case nil:
		return ""
	case string:
		return v
	case fmt.Stringer:
		return v.String()
	case []map[string]any:
		buf, _ := json.Marshal(v)
		return string(buf)
	default:
		return strings.TrimSpace(fmt.Sprint(v))
	}
}

func toFloat(value any) float64 {
	switch v := value.(type) {
	case int:
		return float64(v)
	case int64:
		return float64(v)
	case float64:
		return v
	case float32:
		return float64(v)
	case json.Number:
		f, _ := v.Float64()
		return f
	case string:
		f, _ := strconv.ParseFloat(strings.TrimSpace(v), 64)
		return f
	default:
		return 0
	}
}

func asMap(value any) map[string]any {
	switch v := value.(type) {
	case map[string]any:
		return v
	case map[string]string:
		ret := make(map[string]any, len(v))
		for key, item := range v {
			ret[key] = item
		}
		return ret
	case string:
		var ret map[string]any
		if err := json.Unmarshal([]byte(strings.TrimSpace(v)), &ret); err == nil {
			return ret
		}
	}
	return map[string]any{}
}

func truthy(value any) bool {
	switch v := value.(type) {
	case nil:
		return false
	case bool:
		return v
	case string:
		normalized := strings.ToLower(strings.TrimSpace(v))
		return normalized != "" && normalized != "false" && normalized != "0"
	default:
		return !reflect.ValueOf(value).IsZero()
	}
}

func exists(value any) bool {
	if value == nil {
		return false
	}
	switch v := value.(type) {
	case string:
		return strings.TrimSpace(v) != ""
	default:
		return true
	}
}

func hasItems(value any) bool {
	if value == nil {
		return false
	}
	rv := reflect.ValueOf(value)
	switch rv.Kind() {
	case reflect.Array, reflect.Slice, reflect.Map:
		return rv.Len() > 0
	default:
		return exists(value)
	}
}