from pathlib import Path
from fractions import Fraction as Q
import re

def run(load,check):
 text=(Path(__file__).resolve().parent.parent/'sources/BILATERAL.md').read_text()
 parsed=re.findall(r'\| G([1-3]) (close|start) \| (\d+) \| (\d+) \| (\d+) \| (\d+) \|',text)
 check('six documented bilateral rows',len(parsed)==6)
 reg=load('C271_REGISTER.json');rows=[]
 for gear,kind,C,R,ON,MT in parsed:
  C,R,ON,MT=map(int,[C,R,ON,MT]);j=R-3103;S=-5890+j;A=-C
  match=[r for r in reg if r['branch']=='Flood' and r['source_event']['gear']==int(gear) and r['selector']==kind]
  check(f'bound endpoint j{j}',len(match)==1 and match[0]['source_event']['BC_Nisan']==R)
  check(f'triangle widths j{j}',A-S==598 and R-A==8395 and R-S==8993)
  for e in [Q(-1,4),Q(1,4)]:check(f'path component j{j} {e}',S+e+598+8395==S+e+8993==R+e)
  rows.append({'index_j':j,'Shem_signed':S,'Flood_partner_signed':A,'regular_id':match[0]['id'],'regular_reflected':R,'triangle':[598,8395,8993],'bilateral_ON_C':ON,'bilateral_MT_R':MT})
 check('all six endpoints retained',[r['index_j'] for r in rows]==list(range(2,8)))
 check('K and23 decomposition',8993==17*529 and 8395==23*365 and 8993-8395==598)
 return {'triangles':rows,'shared_endpoint_count':6,'composition':'T8395 after T598 equals T8993','no_regular_Noah_required_for_triangle':True,'source_path_status':'derived triangle of admitted endpoint comparisons; not six new stored C127 paths'}