import rhinoscriptsyntax as rs
import math

rs.DeleteObjects(rs.AllObjects())

# Staircase parameters
thick = 0.2          # Step thickness
s_width = 3.5        # Stair width
tt = 0.45            # Tread depth
th = 0.18            # Step height
steps = 300          # Total number of steps
loops = 6            # Number of loops
radius = 6           # Radius of the helix
height = 30          # Total height of the staircase
DC = 80              # Direction change interval
P = 40               # Landing interval

# Function to create a helical curve
def make_helix(radius, height, loops, steps):
    points = []
    for i in range(steps + 1):
        angle = (360 * loops / steps) * i  # Angle in degrees
        x = radius * math.cos(math.radians(angle))
        y = radius * math.sin(math.radians(angle))
        z = (height / steps) * i
        points.append([x, y, z])
    return rs.AddInterpCurve(points)

# Function to create the staircase
def make_curved_podeststair(curve, th=th, tt=tt, steps=steps, thick=thick, s_width=s_width, DC=DC, P=P):
    pts = [[0, 0, 0]]
    for i in range(1, steps):
        if not (i % DC):   # Direction change
            th = -th
            pts.append([pts[-1][0] + tt, pts[-1][1], pts[-1][2]])
        elif not (i % P):  # Landing
            pts.append([pts[-1][0] + s_width, pts[-1][1], pts[-1][2]])
            pts.append([pts[-1][0] + tt, pts[-1][1], pts[-1][2]])
        else:              # Regular step
            pts.append([pts[-1][0], pts[-1][1], pts[-1][2] + th])
            pts.append([pts[-1][0] + tt, pts[-1][1], pts[-1][2]])
    
    if th < 0:  # Final adjustment for downward step
        pts.append([pts[-1][0], pts[-1][1], pts[-1][2] + th])

    # Create the closed polyline for the step outline
    return_list = []
    for i in range(-1, -len(pts), -2):
        return_list.append([pts[i][0], pts[i][1], pts[i][2] - thick])
    pts.extend(return_list)
    pts.append([pts[0][0], pts[0][1], pts[0][2] - thick])
    pts.append(pts[0])
    
    s_outline = rs.AddPolyline(pts)
    path = rs.AddLine(pts[0], [pts[0][0], pts[0][1] + s_width, pts[0][2]])
    shadow = rs.AddLine(pts[0], [return_list[0][0], return_list[0][1], pts[0][2]])
    s_surf = rs.AddPlanarSrf(s_outline)
    
    rs.Command("_Flow _selID {} _Enter _selID {} _selID {} _Enter".format(s_surf[0], shadow, curve), False)
    profile = rs.FirstObject()
    stair = rs.OffsetSurface(profile, s_width / 4, both_sides=True, create_solid=True)
    rs.DeleteObjects([s_surf[0], shadow, curve, path, s_outline, profile])
    return stair

# Disable redraw for better performance
rs.EnableRedraw(False)

# Create the helical curve
curve = make_helix(radius, height, loops, steps)

# Create the staircase along the helical curve
staircase = make_curved_podeststair(curve, th=th, tt=tt, steps=steps, thick=thick, s_width=s_width, DC=DC, P=P)

rs.EnableRedraw(True)