import numpy as np
import h5py
from util.util import get_grid_values, is_day
import glob

# target_param = 'cloud_probability'
# target_param = 'cld_opd_dcomp'
target_param = 'cld_opd_dcomp_1'
# target_param = 'cld_opd_dcomp_2'
# target_param = 'cld_opd_dcomp_3'

group_name_i = 'super/'
group_name_m = 'orig/'

solzen_name = group_name_m + 'solar_zenith'
snow_class_name = group_name_m + 'snow_class'

# params_i = [group_name_i+'temp_ch38', group_name_i+'refl_ch01', group_name_i+target_param]
params_i = [group_name_i+'temp_ch38', group_name_i+'refl_ch01', group_name_i+'temp_stddev3x3_ch31', group_name_i+'refl_stddev3x3_ch01', group_name_i+target_param]
params_m = [group_name_m+'temp_ch38', group_name_m+'refl_ch01', group_name_m+'refl_submin_ch01', group_name_m+'refl_submax_ch01', group_name_m+'refl_substddev_ch01', group_name_m+'temp_stddev3x3_ch31', group_name_m+'refl_stddev3x3_ch01', group_name_m+target_param]
            # group_name_m+'refl_submax_ch01', group_name_m+'refl_substddev_ch01', group_name_m+target_param]

param_idx_m = params_m.index(group_name_m + target_param)
param_idx_i = params_i.index(group_name_i + target_param)


def snow_covered(tile):
    return np.any(tile > 1)


def is_missing(p_idx, tile):
    keep = np.invert(np.isnan(tile[p_idx, ]))
    if np.sum(keep) / keep.size < 0.98:
        return True


def keep_tile(p_idx, tile):
    grd_k = tile[p_idx, ].copy()

    if target_param == 'cloud_probability':
        grd_k = process_cld_prob(grd_k)
    elif 'cld_opd_dcomp' in target_param:
        grd_k = process_cld_opd(grd_k)

    if grd_k is not None:
        tile[p_idx, ] = grd_k
        return tile
    else:
        return None


def process_cld_prob(grd_k):
    keep = np.invert(np.isnan(grd_k))
    num_keep = np.sum(keep)
    # keep_clr = np.where(keep, grd_k < 0.30, False)
    keep_cld = np.where(keep, grd_k > 0.70, False)
    # frac_clr = np.sum(keep_clr)/num_keep
    frac_cld = np.sum(keep_cld)/num_keep
    if not (0.10 <= frac_cld <= 0.90):
        return None
    grd_k = np.where(np.invert(keep), 0, grd_k)  # Convert NaN to 0
    return grd_k


def process_cld_opd(grd_k):
    keep = np.invert(np.isnan(grd_k))
    num_keep = np.sum(keep)
    keep_cld = np.where(keep, np.logical_and(2.0 < grd_k, grd_k < 158.0), False)
    # keep_cld = np.where(keep, 2.0 < grd_k, False)
    frac_cld = np.sum(keep_cld)/num_keep
    # if not (0.40 < frac_cld):
    if not (0.10 < frac_cld < 0.90):
        return None
    grd_k = np.where(np.invert(keep), 0, grd_k)  # Convert NaN to 0
    return grd_k


def run_all(directory, out_directory, day_night='ANY', pattern='clavrx_*.nc', start=10, is_snow_covered=None):
    cnt = start
    total_num_train_samples = 0
    total_num_valid_samples = 0

    # path = directory + '**' + '/' + pattern
    path = directory + '*_v3/2020/' + '**' + '/' + pattern

    all_files = glob.glob(path, recursive=True)
    valid_files = glob.glob(directory + '*_v3/2020/*/0[1-5]/*/*.nc', recursive=True)
    train_files = [f for f in all_files if f not in valid_files]

    data_tiles_i = []
    data_tiles_m = []
    f_cnt = 0

    num_files = len(valid_files)
    print('Start, number of valid files: ', num_files)

    total_num_not_missing = 0
    num_skip = 4

    param_train_hist = np.zeros([20], dtype=np.int64)
    param_valid_hist = np.zeros([20], dtype=np.int64)

    for idx, data_f in enumerate(valid_files):
        if idx % num_skip == 0:  # if we want to skip some files
            try:
                h5f = h5py.File(data_f, 'r')
            except:
                print('cant open file: ', data_f)
                continue

            try:
                num_not_missing, num_snow_covered = \
                    run(h5f, params_m, data_tiles_m, params_i, data_tiles_i,
                        # tile_width=16, kernel_size=4, factor=4,
                        tile_width=64, kernel_size=7, factor=2,
                        day_night=day_night, is_snow_covered=is_snow_covered)
            except Exception as e:
                print(e)
                h5f.close()
                continue
            print(data_f)
            f_cnt += 1
            h5f.close()

            total_num_not_missing += num_not_missing

            if len(data_tiles_m) == 0:
                continue

            if (f_cnt % 100) == 0:
                num_valid_samples = 0
                if len(data_tiles_m) > 0:
                    valid_i = np.stack(data_tiles_i)
                    valid_m = np.stack(data_tiles_m)
                    np.save(out_directory + 'valid_mres_' + str(cnt), valid_m)
                    np.save(out_directory + 'valid_ires_' + str(cnt), valid_i)
                    num_valid_samples = valid_m.shape[0]

                    param_valid_hist += np.histogram(valid_m[param_idx_m, ], bins=20, range=[0.0, 160.0])[0]

                data_tiles_i = []
                data_tiles_m = []

                print('  num_valid_samples, progress % : ', num_valid_samples, int((f_cnt/(num_files/num_skip))*100))
                total_num_valid_samples += num_valid_samples
                print('total_num_valid_samples, total_num_not_missing: ', total_num_valid_samples, total_num_not_missing)
                print('--------------------------------------------------')

                cnt += 1

    # Write out leftover, if any. Maybe make this better someday
    num_valid_samples = 0
    if len(data_tiles_m) > 0:
        valid_i = np.stack(data_tiles_i)
        valid_m = np.stack(data_tiles_m)
        np.save(out_directory + 'valid_mres_' + str(cnt), valid_m)
        np.save(out_directory + 'valid_ires_' + str(cnt), valid_i)
        num_valid_samples = valid_m.shape[0]
        param_valid_hist += np.histogram(valid_m[param_idx_m, ], bins=20, range=[0.0, 160.0])[0]
    total_num_valid_samples += num_valid_samples
    print('total_num_valid_samples, total_num_not_missing: ', total_num_valid_samples, total_num_not_missing)
    print(param_valid_hist)
    print('--------------------------------------------------')
    print('----------------------------------------------------------------')

    data_tiles_i = []
    data_tiles_m = []
    f_cnt = 0
    total_num_not_missing = 0
    num_files = len(train_files)
    print('Start, number of train files: ', num_files)

    for idx, data_f in enumerate(train_files):
        if idx % num_skip == 0:  # if we want to skip some files
            try:
                h5f = h5py.File(data_f, 'r')
            except:
                print('cant open file: ', data_f)
                continue

            try:
                num_not_missing, num_snow_covered = \
                    run(h5f, params_m, data_tiles_m, params_i, data_tiles_i,
                        # tile_width=16, kernel_size=4, factor=4,
                        tile_width=64, kernel_size=7, factor=2,
                        day_night=day_night, is_snow_covered=is_snow_covered)
            except Exception as e:
                print(e)
                h5f.close()
                continue
            print(data_f)
            f_cnt += 1
            h5f.close()

            total_num_not_missing += num_not_missing

            if len(data_tiles_m) == 0:
                continue

            if (f_cnt % 100) == 0:
                num_train_samples = 0
                if len(data_tiles_m) > 0:
                    train_i = np.stack(data_tiles_i)
                    train_m = np.stack(data_tiles_m)
                    np.save(out_directory + 'train_ires_' + str(cnt), train_i)
                    np.save(out_directory + 'train_mres_' + str(cnt), train_m)
                    num_train_samples = train_m.shape[0]

                    param_train_hist += np.histogram(train_m[param_idx_m, ], bins=20, range=[0.0, 160.0])[0]

                data_tiles_i = []
                data_tiles_m = []

                print('  num_train_samples, progress % : ', num_train_samples, int((f_cnt/(num_files/num_skip))*100))
                total_num_train_samples += num_train_samples
                print('total_num_train_samples, total_num_not_missing: ', total_num_train_samples, total_num_not_missing)
                print('--------------------------------------------------')

                cnt += 1

    # Write out leftover, if any. Maybe make this better someday
    num_train_samples = 0
    if len(data_tiles_m) > 0:
        train_i = np.stack(data_tiles_i)
        train_m = np.stack(data_tiles_m)
        np.save(out_directory + 'train_ires_' + str(cnt), train_i)
        np.save(out_directory + 'train_mres_' + str(cnt), train_m)
        num_train_samples = train_m.shape[0]
        param_train_hist += np.histogram(train_m[param_idx_m, ], bins=20, range=[0.0, 160.0])[0]
    total_num_train_samples += num_train_samples
    print('total_num_train_samples,  total_num_not_missing: ', total_num_train_samples, total_num_not_missing)
    print(param_train_hist)
    print('--------------------------------------------------')

    print('*** total_num_train_samples, total_num_valid_samples: ', total_num_train_samples, total_num_valid_samples)


#  tile_width: Must be even!
#  kernel_size: Must be odd!
def run(h5f, params_m, data_tiles_m, params_i, data_tiles_i, tile_width=64, kernel_size=3, factor=2,
        day_night='ANY', is_snow_covered=None):

    border = int((kernel_size - 1)/2) + 1  # Need to add for interpolation with no edge effects

    param_name = params_m[0]

    num_lines = h5f[param_name].shape[0]
    num_pixels = h5f[param_name].shape[1]  # Must be even

    if day_night != 'ANY':
        solzen = get_grid_values(h5f, solzen_name, 0, 0, None, num_lines, num_pixels)

    if is_snow_covered is not None:
        snow = get_grid_values(h5f, snow_class_name, 0, 0, None, num_lines, num_pixels)

    grd_s = []
    for param in params_m:
        try:
            grd = get_grid_values(h5f, param, 0, 0, None, num_lines, num_pixels)
            grd_s.append(grd)
        except Exception as e:
            print(e)
            return
    data_m = np.stack(grd_s)

    grd_s = []
    for param in params_i:
        try:
            grd = get_grid_values(h5f, param, 0, 0, None, num_lines*factor, num_pixels*factor)
            grd_s.append(grd)
        except Exception as e:
            print(e)
            return
    data_i = np.stack(grd_s)

    tile_width += 2 * border

    i_skip = tile_width
    j_skip = tile_width
    i_start = border - 1  # zero-based
    j_start = border - 1  # zero-based

    num_y_tiles = int(num_lines / tile_width)
    num_x_tiles = int(num_pixels / tile_width)

    num_not_missing = 0
    num_snow_covered = 0

    for j in range(num_y_tiles):
        j_a = j_start + j * j_skip
        j_b = j_a + tile_width

        for i in range(num_x_tiles):
            i_a = i_start + i * i_skip
            i_b = i_a + tile_width

            if is_snow_covered is not None:
                if is_snow_covered:
                    if not snow_covered(snow[j_a:j_b, i_a:i_b]):
                        continue
                    num_snow_covered += 1
                else:
                    if snow_covered(snow[j_a:j_b, i_a:i_b]):
                        num_snow_covered += 1
                        continue

            if day_night == 'DAY' and not is_day(solzen[j_a:j_b, i_a:i_b]):
                continue
            elif day_night == 'NIGHT' and is_day(solzen[j_a:j_b, i_a:i_b]):
                continue

            nda_m = data_m[:, j_a:j_b, i_a:i_b]
            nda_i = data_i[:, j_a*factor:j_b*factor, i_a*factor:i_b*factor]
            if is_missing(param_idx_i, nda_i):
                continue
            num_not_missing += 1

            nda_i = keep_tile(param_idx_i, nda_i)
            if nda_i is not None:
                data_tiles_m.append(nda_m)
                data_tiles_i.append(nda_i)

    return num_not_missing, num_snow_covered