;;; ------------------------------------------------------------
;;; AutoCATS 리습 자료실
;; 명령: LLABEL
;; 기능: 선택한 곡선 중점에 길이를 접선 방향 문자로 표기
;; 출처: https://www.autocats.co.kr/lisp/length-label
;; 버전: 1.0 (2026-07-23)
;; 라이선스: 자유 사용·수정, 재배포 시 출처(autocats.co.kr) 표기
;; 안전: *error* 핸들러 + UNDO 그룹, 원본 곡선 수정 없음
;;; ------------------------------------------------------------

(vl-load-com)

(defun autocats-llabel-length (ent / result)
  (setq result
        (vl-catch-all-apply
          '(lambda ()
             (vlax-curve-getDistAtParam ent (vlax-curve-getEndParam ent)))))
  (if (vl-catch-all-error-p result) nil result))

(defun autocats-llabel-readable-angle (radians)
  (if (and (> radians (/ pi 2.0)) (< radians (* 1.5 pi)))
    (+ radians pi)
    radians))

(defun autocats-llabel-create (ent precision height / length distance point param deriv angle result)
  (setq length (autocats-llabel-length ent))
  (if length
    (progn
      (setq distance (/ length 2.0)
            point (vlax-curve-getPointAtDist ent distance)
            param (vlax-curve-getParamAtPoint ent point)
            deriv (vlax-curve-getFirstDeriv ent param)
            angle (autocats-llabel-readable-angle
                    (atan (cadr deriv) (car deriv)))
            result
            (entmakex
              (list
                (cons 0 "TEXT")
                (cons 10 point)
                (cons 40 height)
                (cons 1 (rtos length 2 precision))
                (cons 7 (getvar "TEXTSTYLE"))
                (cons 50 angle))))
      result)
    nil))

(defun c:LLABEL (/ *error* doc undo-open ss idx ent precision height created skipped result)
  (defun *error* (msg)
    (if undo-open
      (progn (vla-EndUndoMark doc) (setq undo-open nil)))
    (if (and msg (not (wcmatch (strcase msg) "*CANCEL*,*QUIT*,*EXIT*,*취소*")))
      (princ (strcat "\n[LLABEL] 중단: " msg)))
    (princ))

  (setq precision (getint (strcat "\n[LLABEL] 소수 자릿수 <" (itoa (getvar "DIMDEC")) ">: ")))
  (if (or (null precision) (< precision 0) (> precision 8))
    (setq precision (getvar "DIMDEC")))
  (setq height (getreal (strcat "\n문자 높이 <" (rtos (getvar "TEXTSIZE") 2 precision) ">: ")))
  (if (or (null height) (<= height 0.0)) (setq height (getvar "TEXTSIZE")))
  (princ "\n[LLABEL] 길이를 표기할 곡선을 선택하세요.")
  (setq ss (ssget '((0 . "LINE,LWPOLYLINE,POLYLINE,ARC,CIRCLE,SPLINE,ELLIPSE"))))
  (if ss
    (progn
      (setq doc (vla-get-ActiveDocument (vlax-get-acad-object))
            idx 0 created 0 skipped 0)
      (vla-StartUndoMark doc)
      (setq undo-open T)
      (while (< idx (sslength ss))
        (setq ent (ssname ss idx)
              result
              (vl-catch-all-apply
                'autocats-llabel-create
                (list ent precision height)))
        (if (or (vl-catch-all-error-p result) (null result))
          (setq skipped (1+ skipped))
          (setq created (1+ created)))
        (setq idx (1+ idx)))
      (vla-EndUndoMark doc)
      (setq undo-open nil)
      (princ (strcat "\n[LLABEL] 완료: " (itoa created)
                     "개 표기 / " (itoa skipped) "개 건너뜀")))
    (princ "\n[LLABEL] 선택된 곡선이 없습니다."))
  (princ))

(princ "\n[AutoCATS] LLABEL 로드 완료 - 명령행에 LLABEL 를 입력하세요.")
(princ)