from __future__ import  absolute_import
# though cupy is not used but without this line, it raise errors...
import cupy as cp
import os

import ipdb
import matplotlib
from tqdm import tqdm

from utils.config import opt
from data.dataset import Dataset, TestDataset, inverse_normalize
from model import FasterRCNNVGG16
from torch.utils import data as data_
from trainer import FasterRCNNTrainer
from utils import array_tool as at
from utils.vis_tool import visdom_bbox
from utils.eval_tool import eval_detection_voc

# fix for ulimit
# https://github.com/pytorch/pytorch/issues/973#issuecomment-346405667
import resource

rlimit = resource.getrlimit(resource.RLIMIT_NOFILE)
resource.setrlimit(resource.RLIMIT_NOFILE, (20480, rlimit[1]))

matplotlib.use('agg')


def eval(dataloader, faster_rcnn, test_num=10000):
    pred_bboxes, pred_labels, pred_scores = list(), list(), list()
    gt_bboxes, gt_labels, gt_difficults = list(), list(), list()
    for ii, (imgs, sizes, gt_bboxes_, gt_labels_, gt_difficults_) in tqdm(enumerate(dataloader)):
        sizes = [sizes[0][0].item(), sizes[1][0].item()]
        pred_bboxes_, pred_labels_, pred_scores_ = faster_rcnn.predict(imgs, [sizes])
        gt_bboxes += list(gt_bboxes_.numpy())
        gt_labels += list(gt_labels_.numpy())
        gt_difficults += list(gt_difficults_.numpy())
        pred_bboxes += pred_bboxes_
        pred_labels += pred_labels_
        pred_scores += pred_scores_
        if ii == test_num: break

    result = eval_detection_voc(
        pred_bboxes, pred_labels, pred_scores,
        gt_bboxes, gt_labels, gt_difficults,
        use_07_metric=True)
    return result


def train(**kwargs):
    opt._parse(kwargs)

    dataset = Dataset(opt)
    print('load data')
    dataloader = data_.DataLoader(dataset, \
                                  batch_size=1, \
                                  shuffle=True, \
                                  # pin_memory=True,
                                  num_workers=opt.num_workers)
    testset = TestDataset(opt)
    test_dataloader = data_.DataLoader(testset,
                                       batch_size=1,
                                       num_workers=opt.test_num_workers,
                                       shuffle=False, \
                                       pin_memory=True
                                       )
    faster_rcnn = FasterRCNNVGG16()
    print('model construct completed')
    trainer = FasterRCNNTrainer(faster_rcnn).cuda()
    if opt.load_path:
        trainer.load(opt.load_path)
        print('load pretrained model from %s' % opt.load_path)
    trainer.vis.text(dataset.db.label_names, win='labels')
    best_map = 0
    lr_ = opt.lr
    for epoch in range(opt.epoch):
        trainer.reset_meters()
        for ii, (img, bbox_, label_, scale) in tqdm(enumerate(dataloader)):
            scale = at.scalar(scale)
            img, bbox, label = img.cuda().float(), bbox_.cuda(), label_.cuda()
            trainer.train_step(img, bbox, label, scale)

            if (ii + 1) % opt.plot_every == 0:
                if os.path.exists(opt.debug_file):
                    ipdb.set_trace()

                # plot loss
                trainer.vis.plot_many(trainer.get_meter_data())

                # plot groud truth bboxes
                ori_img_ = inverse_normalize(at.tonumpy(img[0]))
                gt_img = visdom_bbox(ori_img_,
                                     at.tonumpy(bbox_[0]),
                                     at.tonumpy(label_[0]))
                trainer.vis.img('gt_img', gt_img)

                # plot predicti bboxes
                _bboxes, _labels, _scores = trainer.faster_rcnn.predict([ori_img_], visualize=True)
                pred_img = visdom_bbox(ori_img_,
                                       at.tonumpy(_bboxes[0]),
                                       at.tonumpy(_labels[0]).reshape(-1),
                                       at.tonumpy(_scores[0]))
                trainer.vis.img('pred_img', pred_img)

                # rpn confusion matrix(meter)
                trainer.vis.text(str(trainer.rpn_cm.value().tolist()), win='rpn_cm')
                # roi confusion matrix
                trainer.vis.img('roi_cm', at.totensor(trainer.roi_cm.conf, False).float())
        eval_result = eval(test_dataloader, faster_rcnn, test_num=opt.test_num)
        trainer.vis.plot('test_map', eval_result['map'])
        lr_ = trainer.faster_rcnn.optimizer.param_groups[0]['lr']
        log_info = 'lr:{}, map:{},loss:{}'.format(str(lr_),
                                                  str(eval_result['map']),
                                                  str(trainer.get_meter_data()))
        trainer.vis.log(log_info)

        if eval_result['map'] > best_map:
            best_map = eval_result['map']
            best_path = trainer.save(best_map=best_map)
        if epoch == 9:
            trainer.load(best_path)
            trainer.faster_rcnn.scale_lr(opt.lr_decay)
            lr_ = lr_ * opt.lr_decay

        if epoch == 13: 
            break


if __name__ == '__main__':
    import fire

    fire.Fire()