"""Headless runner for dra_ship_install on a ship file (a work copy beside the real one, so relative paths hold).

blender -b --factory-startup -t 8 <ship copy .blend> --python run_ship_install.py -- --stage install --report <json>
    install: apply(), check(), save the file in place (only when the check has no clash)
blender ... -- --stage render --out <folder>      Workbench pictures of both arms over the timeline (file not saved)
blender ... -- --stage check --report <json>      check() only (file not saved)
"""
import json
import math
import os
import sys
import time

import bpy
from mathutils import Vector

HERE = os.path.dirname(os.path.abspath(__file__))
if HERE not in sys.path:
    sys.path.insert(0, HERE)
import dra_ship_install as inst

argv = sys.argv[sys.argv.index("--") + 1:]


def arg(name, default=None):
    return argv[argv.index(name) + 1] if name in argv else default


stage = arg("--stage")
t0 = time.time()

if stage in ("install", "check"):
    out = {"file": bpy.data.filepath, "stage": stage}
    if stage == "install":
        out["apply"] = inst.apply()
    out["check"] = inst.check(step=int(arg("--step", "1")))
    out["seconds"] = round(time.time() - t0, 1)
    ok = not out["check"]["clashes"] and all(
        p["plate_to_pad_mm"] < 0.5 and p["plate_to_pad_deg"] < 0.05 and p["pad_to_door_mm"] < 0.5 for p in out["check"]["pose"].values())
    if stage == "install":
        ok = ok and not out["apply"]["drivers_bad"]
    out["ok"] = ok
    if stage == "install" and ok:
        scn = bpy.data.scenes[inst.SCENE]
        scn.frame_set(1)
        bpy.ops.wm.save_mainfile()
        out["saved"] = bpy.data.filepath
    json.dump(out, open(arg("--report"), "w"), indent=1)
    print("RESULT ok=%s clashes=%d seconds=%.0f" % (ok, len(out["check"]["clashes"]), out["seconds"]))

elif stage == "render":
    folder = arg("--out")
    os.makedirs(folder, exist_ok=True)
    scn = bpy.data.scenes[inst.SCENE]
    r = scn.render
    r.engine = 'BLENDER_WORKBENCH'
    r.resolution_x, r.resolution_y, r.resolution_percentage = 1280, 720, 100
    r.film_transparent = False
    sh = scn.display.shading
    sh.light = 'STUDIO'
    sh.color_type = 'MATERIAL'
    sh.show_cavity = True
    sh.cavity_type = 'BOTH'
    sh.show_object_outline = True
    sh.show_shadows = True
    scn.display.shadow_focus = 0.5
    cam_data = bpy.data.cameras.new("tmp cam")
    cam_data.lens = 20
    cam_data.clip_start = 0.05
    cam = bpy.data.objects.new("tmp cam", cam_data)
    scn.collection.objects.link(cam)
    scn.camera = cam

    def look(eye, target):
        cam.location = Vector(eye)
        d = Vector(target) - Vector(eye)
        cam.rotation_euler = d.to_track_quat('-Z', 'Y').to_euler()

    # the carriage's x at a frame, from the arm itself (follows the door)
    def carriage_x(d):
        dg = scn.view_layers[0].depsgraph
        dg.update()
        return bpy.data.objects["DoorArm_%s_B | carriage" % d].evaluated_get(dg).matrix_world.translation.x

    shots = []
    for d, frames in (("AFT", (1, 12, 30, 48, 90)), ("FORE", (1, 48))):
        s = 1.0 if d == "AFT" else -1.0      # AFT pocket toward -x
        for f in frames:
            shots.append((d, f, "inboard"))
            shots.append((d, f, "along"))
    done = []
    for d, f, view in shots:
        scn.frame_set(f)
        x = carriage_x(d)
        s = 1.0 if d == "AFT" else -1.0
        if view == "inboard":    # from the basin side under the deck, looking outboard at the arm and its door
            look((x + s * 1.6, -1.2, -5.0), (x + s * 0.6, -6.9, -5.6))
        else:                    # from the moon pool end of the pocket, along the rail
            look((x + s * 4.2, -3.6, -4.6), (x - s * 0.2, -6.4, -5.3))
        bpy.context.view_layer.update()
        fn = os.path.join(folder, "ship_%s_B_f%03d_%s.png" % (d, f, view))
        r.filepath = fn
        bpy.ops.render.render(write_still=True, scene=scn.name)
        done.append(os.path.basename(fn))
    print("RENDERED", len(done), round(time.time() - t0, 1))