import base64
import os
import sqlite3


def get_tileset_info(tileset):
    if not os.path.isfile(tileset):
        return {"error": "Tileset info is not available!"}

    db = sqlite3.connect(tileset)

    res = db.execute("SELECT * FROM tileset_info").fetchone()

    o = {"tile_size": res[5], "max_zoom": res[6], "max_size": res[7]}

    try:
        o["width"] = res[8]
        o["height"] = res[9]
    except IndexError:
        pass

    try:
        o["dtype"] = res[10]
    except IndexError:
        pass

    return o


def get_tiles(filename, tile_ids, raw):
    """
    Generate tiles from a imtiles file.
    Parameters
    ----------
    tileset: tilesets.models.Tileset object
        The tileset that the tile ids should be retrieved from
    tile_ids: [str,...]
        A list of tile_ids (e.g. xyx.0.0.1) identifying the tiles
        to be retrieved
    Returns
    -------
    generated_tiles: [(tile_id, tile_data),...]
        A list of tile_id, tile_data tuples
    """
    # Connect to SQLite db
    db = sqlite3.connect(filename)

    generate_tiles = []

    generate_image = raw and len(tile_ids)

    for tile_id in tile_ids:
        id = tile_id[tile_id.find(".") + 1 :].split(".")

        sql = "SELECT image FROM tiles WHERE z = :z AND y = :y AND x = :x"
        param = {"z": int(id[0]), "y": int(id[1]), "x": int(id[2])}
        res = db.execute(sql, param).fetchone()

        if res:
            image_blob = res[0]

            if generate_image:
                tile_data = {"image": image_blob}
            else:
                tile_data = {"dense": base64.b64encode(image_blob).decode("latin-1")}

            generate_tiles.append((tile_id, tile_data))

    return generate_tiles