# Grouper: closed regions of the sheet by flood fill from a seed through non-line pixels (plain Python).
# region(seed, box) -> mask; describe() -> bbox, area, per-row extents. Used to read windows, door, porthole, panels.
import numpy as np
from PIL import Image
import os, json, sys
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from gr_trace import R, dilate, propagate, LINE_T

def region(seed, box, thr=LINE_T, grow=0):
    x0, y0, x1, y1 = box
    line = R[y0:y1, x0:x1] > thr
    if grow:
        line = dilate(line, grow)
    s = np.zeros_like(line)
    s[seed[1] - y0, seed[0] - x0] = True
    m = propagate(s, ~line)
    full = np.zeros(R.shape, bool)
    full[y0:y1, x0:x1] = m
    return full

def describe(m, step=2, axis="rows"):
    ys, xs = np.where(m)
    d = {"bbox": [int(xs.min()), int(ys.min()), int(xs.max()), int(ys.max())], "area": int(m.sum()),
         "centroid": [round(float(xs.mean()), 1), round(float(ys.mean()), 1)]}
    if axis == "rows":
        d["rows"] = [(int(y), int(xs[ys == y].min()), int(xs[ys == y].max())) for y in range(ys.min(), ys.max() + 1, step) if (ys == y).any()]
    else:
        d["cols"] = [(int(x), int(ys[xs == x].min()), int(ys[xs == x].max())) for x in range(xs.min(), xs.max() + 1, step) if (xs == x).any()]
    return d

if __name__ == "__main__":
    SEEDS = json.loads(sys.argv[1])
    for name, (sx, sy, x0, y0, x1, y1, axis, step, grow) in SEEDS.items():
        m = region((sx, sy), (x0, y0, x1, y1), grow=grow)
        print(name, json.dumps(describe(m, step, axis)))