"""
通用性参数

目前只包含 SMAP L4 数据的相关的坐标参数

Reference: 
- https://github.com/arthur-e/pyl4c
"""

EPSG = {
    # EPSG:6933 圆柱等面积投影坐标系可用于全球范围数据, 如 SMAP L4 数据
    6933: """PROJCS["WGS 84 / NSIDC EASE-Grid 2.0 Global",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563,
                AUTHORITY["EPSG","7030"]],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Cylindrical_Equal_Area"],
    PARAMETER["standard_parallel_1",30],
    PARAMETER["central_meridian",0],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    UNIT["metre",1,AUTHORITY["EPSG","9001"]],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    AUTHORITY["EPSG","6933"]]""",
}

EASE2_GRID_PARAMS = {
    # A GeoTransform for a north-up raster is:
    # (x_min, pixel_width, 0, y_max, 0, -pixel_height)
    "M09": {
        "epsg": 6933,
        "geotransform": (-17367530.45, 9000, 0, 7314540.83, 0, -9000),
        "resolution": 9008.055210146,  # From Brodzik et al.
        "shape": (1624, 3856),
        "size": 1624 * 3856,
    },
}