import bpy
from mathutils import Vector, Euler
from math import pi, sqrt
import json
import os
import pathlib
import bmesh

def get_bounds(objects):
    xl = []
    yl = []
    zl = []
    
    for obj in objects:
        for bounds in obj.bound_box:
            v = obj.matrix_world @ Vector(bounds)
            xl += [v[0] for c in obj.bound_box]
            yl += [v[1] for c in obj.bound_box]
            zl += [v[2] for c in obj.bound_box]
            
    return (
        Vector([min(xl), min(yl), min(zl)]),
        Vector([max(xl), max(yl), max(zl)])
    )
    

GROUP_NAME = "Billboards"
GROUP_KIND = "buildings"

path_info = pathlib.Path(bpy.data.filepath).parent.joinpath("macrovision-directory.txt")
config_path = pathlib.Path(open(path_info).read())

json_path = config_path.joinpath("config.json")
config = json.load(open(json_path.resolve(), encoding="utf-8"))

parent_workdir = config["work-directory"]
workdir = pathlib.Path(parent_workdir).joinpath(GROUP_NAME)

c = bpy.data.objects["cam"]
c.data.type = "ORTHO"

bpy.data.scenes["Scene"].render.resolution_x = 1000
bpy.data.scenes["Scene"].render.resolution_y = 1000
bpy.data.scenes["Scene"].render.film_transparent = True
bpy.data.scenes["Scene"].view_settings.view_transform = "Raw"

bpy.data.worlds["World"].node_tree.nodes["Background"].inputs[1].default_value = 0

collections = bpy.data.collections["Macrovision"].children

all_data = {}

all_data["name"] = GROUP_NAME
all_data["kind"] = GROUP_KIND
all_data["forms"] = []

VOLUME = False

os.makedirs(workdir, exist_ok=True)

VIEW_DATA = {
    "Front": [0, 1, 2, "Front"],
    "Angled": [0.5, 1, 2, "Angled"],
    "Side": [1, 1, 2, "Side"],
    "Back": [2, 1, 2, "Back"],
    "Top": [0, 0, 1, "Top"]
}

for coll in collections:
    coll.hide_render = True

for coll in collections:
        
    coll.hide_render = False
    
    bpy.ops.object.select_all(action='DESELECT')
    
    for obj in coll.objects:
        obj.select_set(True)

    data = {}
    
    data["name"] = coll.name
    data["views"] = []

    bound_min, bound_max = get_bounds(coll.objects)
    dimensions = bound_max - bound_min
    size = max(dimensions)
    global_bbox_center = 0.5 * (bound_min + bound_max)
    
    view_list = []
    
    if "Views" in coll:
        for view in coll["Views"].split(","):
            view_list.append(VIEW_DATA[view])
    else:
        view_list = [VIEW_DATA["Front"]]            

    for angles in view_list:
        c.location = global_bbox_center
        largest = size
        c.data.ortho_scale = largest * 1.2
        if angles[0] % 1 != 0:
            c.data.ortho_scale *= sqrt(2)
        c.rotation_euler = Euler([angles[1] * pi / 2, 0, angles[0] * pi / 2])
        rot = c.rotation_euler.to_matrix()
        rot.invert()
        c.location = c.location + Vector([0, 0, largest * 2]) @ rot
        c.data.clip_start = largest / 4
        c.data.clip_end = largest * 4
        data["views"].append({
            "name": angles[3],
            "height": dimensions[angles[2]]
        })
        #s.rotation_euler = c.rotation_euler
        filename = f"{coll.name}-{angles[3]}.png"
        bpy.context.scene.render.filepath = workdir.joinpath(filename).resolve().__str__()
        bpy.ops.render.render(write_still = True)
        
    all_data["forms"].append(data)
    coll.hide_render = True

with open(workdir.joinpath("data.json"), "w") as file:
    json.dump(all_data, file)