import os
import sys

import numpy as np
import matplotlib.image as mpimg

from . import raw_records
from ..core.data import Data
from ..util import tryremove
from ..core.input import frame_name_to_num


def exclude_test_and_train_images(kitti_dir, exclude_lists_dir, exclude_target_dir,
                                  remove=False):
    to_move = []

    def exclude_from_seq(day_name, seq_str, image, view, distance=10):
        # image is the first frame of each frame pair to exclude
        seq_dir_rel = os.path.join(day_name, seq_str, view, 'data')
        seq_dir_abs = os.path.join(kitti_dir, seq_dir_rel)
        target_dir_abs = os.path.join(exclude_target_dir, seq_dir_rel)
        if not os.path.isdir(seq_dir_abs):
            print("Not found: {}".format(seq_dir_abs))
            return
        try:
            os.makedirs(target_dir_abs)
        except:
            pass
        seq_files = sorted(os.listdir(seq_dir_abs))
        image_num = frame_name_to_num(image)
        try:
            image_index = seq_files.index(image)
        except ValueError:
            return
        # assume that some in-between files may be missing
        start = max(0, image_index - distance)
        stop = min(len(seq_files), image_index + distance + 2)
        start_num = image_num - distance
        stop_num = image_num + distance + 2
        for i in range(start, stop):
            filename = seq_files[i]
            num = frame_name_to_num(filename)
            if num < start_num or num >= stop_num:
                continue
            to_move.append((os.path.join(seq_dir_abs, filename),
                            os.path.join(target_dir_abs, filename)))

    for filename in os.listdir(exclude_lists_dir):
        exclude_list_path = os.path.join(exclude_lists_dir, filename)
        with open(exclude_list_path) as f:
            for line in f:
                line = line.rstrip('\n')
                if line.split(' ')[0].endswith('_10'):
                    splits = line.split(' ')[-1].split('\\')
                    image = splits[-1]
                    seq_str = splits[0]
                    day_name, seq_name = seq_str.split('_drive_')
                    seq_name = seq_name.split('_')[0] + '_extract'
                    seq_str = day_name + '_drive_' + seq_name
                    exclude_from_seq(day_name, seq_str, image, 'image_02')
                    exclude_from_seq(day_name, seq_str, image, 'image_03')
    if remove:
        print("Collected {} files. Deleting...".format(len(to_move)))
    else:
        print("Collected {} files. Moving...".format(len(to_move)))

    for i, data in enumerate(to_move):
        try:
            src, dst = data
            print("{} / {}: {}".format(i, len(to_move) - 1, src))
            if remove:
                os.remove(src)
            else:
                os.rename(src, dst)
        except: # Some ranges may overlap
            pass

    return len(to_move)


class KITTIData(Data):
    KITTI_RAW_URL = 'https://s3.eu-central-1.amazonaws.com/avg-kitti/raw_data/'
    KITTI_2012_URL = 'https://s3.eu-central-1.amazonaws.com/avg-kitti/data_stereo_flow.zip'
    KITTI_2015_URL = 'https://s3.eu-central-1.amazonaws.com/avg-kitti/data_scene_flow.zip'

    dirs = ['data_stereo_flow', 'data_scene_flow', 'kitti_raw']

    def __init__(self, data_dir, stat_log_dir=None,
                 development=True, fast_dir=None):
        super().__init__(data_dir, stat_log_dir,
                         development=development,
                         fast_dir=fast_dir)

    def _fetch_if_missing(self):
        self._maybe_get_kitti_raw()
        self._maybe_get_kitti_2012()
        self._maybe_get_kitti_2015()

    def get_raw_dirs(self):
       top_dir = os.path.join(self.current_dir, 'kitti_raw')
       dirs = []
       dates = os.listdir(top_dir)
       for date in dates:
           date_path = os.path.join(top_dir, date)
           extracts = os.listdir(date_path)
           for extract in extracts:
               extract_path = os.path.join(date_path, extract)
               image_02_folder = os.path.join(extract_path, 'image_02/data')
               image_03_folder = os.path.join(extract_path, 'image_03/data')
               dirs.extend([image_02_folder, image_03_folder])
       return dirs

    def _maybe_get_kitti_2012(self):
        local_path = os.path.join(self.data_dir, 'data_stereo_flow')
        if not os.path.isdir(local_path):
            self._download_and_extract(self.KITTI_2012_URL, local_path)

    def _maybe_get_kitti_2015(self):
        local_path = os.path.join(self.data_dir, 'data_scene_flow')
        if not os.path.isdir(local_path):
            self._download_and_extract(self.KITTI_2015_URL, local_path)

    def _maybe_get_kitti_raw(self):
        base_url = self.KITTI_RAW_URL
        local_dir = os.path.join(self.data_dir, 'kitti_raw')
        records = raw_records.get_kitti_records(self.development)
        downloaded_records = False
          
        for i, record in enumerate(records):
            date_str = record.split("_drive_")[0]
            foldername = record + "_extract"
            date_folder = os.path.join(local_dir, date_str)
            if not os.path.isdir(date_folder):
                os.makedirs(date_folder)
            local_path = os.path.join(date_folder, foldername)
            if not os.path.isdir(local_path):
                url = base_url + record + "/" + foldername + '.zip'
                print(url)
                self._download_and_extract(url, local_dir)
                downloaded_records = True

            # Remove unused directories
            tryremove(os.path.join(local_path, 'velodyne_points'))
            tryremove(os.path.join(local_path, 'oxts'))
            tryremove(os.path.join(local_path, 'image_00'))
            tryremove(os.path.join(local_path, 'image_01'))
            
        if downloaded_records:
            print("Downloaded all KITTI raw files.")
            exclude_target_dir = os.path.join(self.data_dir, 'exclude_target_dir')
            exclude_lists_dir = '../files/kitti_excludes'
            excluded = exclude_test_and_train_images(local_dir, exclude_lists_dir, exclude_target_dir,
                                                     remove=True)