package chat

import (
	"context"
	"fmt"
	"strconv"
	"strings"
	"time"

	"chat-agent-system/internal/bizdev"
	"chat-agent-system/internal/coordinator"
	"chat-agent-system/internal/docgov"
	"chat-agent-system/internal/taskrun"
)

// ActionServices 对话层执行 PendingAction 所需的后端服务。
type ActionServices struct {
	DocGov   *docgov.GovernanceEngine
	Bizdev   bizdev.BizdevService
	TaskRuns *taskrun.Manager
}

// ActionExecResult 动作执行结果摘要。
type ActionExecResult struct {
	DocState string
	RunID    string
	Message  string
}

func parseUserID(userID string) int64 {
	id, _ := strconv.ParseInt(strings.TrimSpace(userID), 10, 64)
	return id
}

func actorName(userCtx *coordinator.UserProjectContext) string {
	if userCtx == nil {
		return "用户"
	}
	if userCtx.User.Name != "" {
		return userCtx.User.Name
	}
	return "用户"
}

func (s *Session) executeAction(ctx context.Context, action *coordinator.PendingAction, userCtx *coordinator.UserProjectContext) (*ActionExecResult, error) {
	if action == nil || s.Actions == nil {
		return nil, fmt.Errorf("action services not configured")
	}
	uid := s.UserID
	if uid <= 0 {
		uid = parseUserID(userCtx.User.ID)
	}
	name := actorName(userCtx)

	switch action.Kind {
	case "docgov.review_approve":
		if s.Actions.DocGov == nil {
			return nil, fmt.Errorf("docgov engine not available")
		}
		doc, err := s.Actions.DocGov.ReviewApprove(ctx, action.DocID, uid, docgov.RoleReviewer, name, action.Comment)
		if err != nil {
			return nil, err
		}
		return &ActionExecResult{DocState: string(doc.CurrentState), Message: "审核通过"}, nil

	case "docgov.approver_approve":
		if s.Actions.DocGov == nil {
			return nil, fmt.Errorf("docgov engine not available")
		}
		doc, err := s.Actions.DocGov.ApproverApprove(ctx, action.DocID, uid, docgov.RoleApprover, name, action.Comment)
		if err != nil {
			return nil, err
		}
		return &ActionExecResult{DocState: string(doc.CurrentState), Message: "终审批准"}, nil

	case "docgov.reject":
		if s.Actions.DocGov == nil {
			return nil, fmt.Errorf("docgov engine not available")
		}
		reason := action.Reason
		if reason == "" {
			reason = "用户确认驳回"
		}
		doc, err := s.Actions.DocGov.ReviewReject(ctx, action.DocID, uid, docgov.RoleReviewer, name, reason)
		if err != nil {
			rollback := action.Rollback
			if rollback == "" {
				rollback = docgov.StateDrafting
			}
			doc, err = s.Actions.DocGov.ApproverReject(ctx, action.DocID, uid, docgov.RoleApprover, name, reason, rollback)
			if err != nil {
				return nil, err
			}
		}
		return &ActionExecResult{DocState: string(doc.CurrentState), Message: "驳回完成"}, nil

	case "taskrun.resume", "taskrun.restart":
		if s.Actions.TaskRuns == nil || s.Actions.Bizdev == nil {
			return nil, fmt.Errorf("task run services not available")
		}
		taskKey := action.TaskKey
		if taskKey == "" {
			taskKey = "intake"
		}
		runID := fmt.Sprintf("run_%d", time.Now().UnixNano())
		resumeDir := ""
		if action.Kind == "taskrun.resume" {
			resumeDir = action.WorkDir
		}
		taskReq := bizdev.TaskRunRequest{
			TaskKey:     taskKey,
			ProjectName: userCtx.Project.Name,
			UserID:      uid,
			ProjectID:   s.ProjectID,
			SessionID:   s.ID,
		}
		record := &taskrun.RunRecord{
			RunID:     runID,
			SessionID: s.ID,
			ProjectID: s.ProjectID,
			UserID:    uid,
			TaskKey:   taskKey,
			Status:    "running",
		}
		created, err := s.Actions.TaskRuns.CreateAndStart(ctx, runID, record, taskReq, bizdev.StageRunRequest{}, resumeDir)
		if err != nil {
			return nil, err
		}
		return &ActionExecResult{RunID: created.RunID, Message: "任务已启动"}, nil

	default:
		return nil, fmt.Errorf("unsupported pending action: %s", action.Kind)
	}
}

func renderActionReply(action *coordinator.PendingAction, result *ActionExecResult, execErr error) string {
	docName := action.DocID
	if docName == "" {
		docName = "当前任务"
	}
	if execErr != nil {
		return fmt.Sprintf("操作未能完成：%s", execErr.Error())
	}
	if result == nil {
		return "操作已完成。"
	}
	switch action.Kind {
	case "docgov.review_approve":
		return fmt.Sprintf("已确认审核通过！《%s》已流转至批准环节（当前状态：%s）。", docName, result.DocState)
	case "docgov.approver_approve":
		return fmt.Sprintf("已确认终审批准！《%s》已被法定受控锁定并正式归档生效（当前状态：%s）。", docName, result.DocState)
	case "docgov.reject":
		return fmt.Sprintf("已确认执行驳回操作！《%s》已退回（当前状态：%s），驳回意见已同步下发。", docName, result.DocState)
	case "taskrun.resume":
		return fmt.Sprintf("续跑任务已启动（run_id=%s）。您可在任务面板查看进度。", result.RunID)
	case "taskrun.restart":
		return fmt.Sprintf("任务已重新启动（run_id=%s）。您可在任务面板查看进度。", result.RunID)
	default:
		if result.Message != "" {
			return result.Message
		}
		return "操作已完成。"
	}
}