⚙️ API reference

def count_overlaps(
    df1: Union[str, pl.DataFrame, pl.LazyFrame, pd.DataFrame],
    df2: Union[str, pl.DataFrame, pl.LazyFrame, pd.DataFrame],
    overlap_filter: FilterOp = FilterOp.Strict,
    suffixes: tuple[str, str] = ("", "_"),
    cols1: Union[list[str], None] = ["chrom", "start", "end"],
    cols2: Union[list[str], None] = ["chrom", "start", "end"],
    on_cols: Union[list[str], None] = None,
    output_type: str = "polars.LazyFrame",
    streaming: bool = False,
    naive_query: bool = True,
) -> Union[pl.LazyFrame, pl.DataFrame, pd.DataFrame, datafusion.DataFrame]:
    """
    Count pairs of overlapping genomic intervals.
    Bioframe inspired API.

    Parameters:
        df1: Can be a path to a file, a polars DataFrame, or a pandas DataFrame or a registered table (see [register_vcf](api.md#polars_bio.register_vcf)). CSV with a header, BED and Parquet are supported.
        df2: Can be a path to a file, a polars DataFrame, or a pandas DataFrame or a registered table. CSV with a header, BED  and Parquet are supported.
        overlap_filter: FilterOp, optional. The type of overlap to consider(Weak or Strict). Strict for **0-based**, Weak for **1-based** coordinate systems.
        suffixes: Suffixes for the columns of the two overlapped sets.
        cols1: The names of columns containing the chromosome, start and end of the
            genomic intervals, provided separately for each set.
        cols2:  The names of columns containing the chromosome, start and end of the
            genomic intervals, provided separately for each set.
        on_cols: List of additional column names to join on. default is None.
        output_type: Type of the output. default is "polars.LazyFrame", "polars.DataFrame", or "pandas.DataFrame" or "datafusion.DataFrame" are also supported.
        naive_query: If True, use naive query for counting overlaps based on overlaps.
        streaming: **EXPERIMENTAL** If True, use Polars [streaming](features.md#streaming) engine.
    Returns:
        **polars.LazyFrame** or polars.DataFrame or pandas.DataFrame of the overlapping intervals.

    Example:
        ```python
        import polars_bio as pb
        import pandas as pd

        df1 = pd.DataFrame([
            ['chr1', 1, 5],
            ['chr1', 3, 8],
            ['chr1', 8, 10],
            ['chr1', 12, 14]],
        columns=['chrom', 'start', 'end']
        )

        df2 = pd.DataFrame(
        [['chr1', 4, 8],
         ['chr1', 10, 11]],
        columns=['chrom', 'start', 'end' ]
        )
        counts = pb.count_overlaps(df1, df2, output_type="pandas.DataFrame")

        counts

        chrom  start  end  count
        0  chr1      1    5      1
        1  chr1      3    8      1
        2  chr1      8   10      0
        3  chr1     12   14      0
        ```

    Todo:
         Support return_input.
    """
    _validate_overlap_input(cols1, cols2, on_cols, suffixes, output_type, how="inner")
    my_ctx = get_py_ctx()
    on_cols = [] if on_cols is None else on_cols
    cols1 = DEFAULT_INTERVAL_COLUMNS if cols1 is None else cols1
    cols2 = DEFAULT_INTERVAL_COLUMNS if cols2 is None else cols2
    if naive_query:
        range_options = RangeOptions(
            range_op=RangeOp.CountOverlapsNaive,
            filter_op=overlap_filter,
            suffixes=suffixes,
            columns_1=cols1,
            columns_2=cols2,
            streaming=streaming,
        )
        return range_operation(df2, df1, range_options, output_type, ctx)
    df1 = read_df_to_datafusion(my_ctx, df1)
    df2 = read_df_to_datafusion(my_ctx, df2)

    # TODO: guarantee no collisions
    s1start_s2end = "s1starts2end"
    s1end_s2start = "s1ends2start"
    contig = "contig"
    count = "count"
    starts = "starts"
    ends = "ends"
    is_s1 = "is_s1"
    suff, _ = suffixes
    df1, df2 = df2, df1
    df1 = df1.select(
        *(
            [
                literal(1).alias(is_s1),
                col(cols1[1]).alias(s1start_s2end),
                col(cols1[2]).alias(s1end_s2start),
                col(cols1[0]).alias(contig),
            ]
            + on_cols
        )
    )
    df2 = df2.select(
        *(
            [
                literal(0).alias(is_s1),
                col(cols2[2]).alias(s1end_s2start),
                col(cols2[1]).alias(s1start_s2end),
                col(cols2[0]).alias(contig),
            ]
            + on_cols
        )
    )

    df = df1.union(df2)

    partitioning = [col(contig)] + [col(c) for c in on_cols]
    df = df.select(
        *(
            [
                s1start_s2end,
                s1end_s2start,
                contig,
                is_s1,
                datafusion.functions.sum(col(is_s1))
                .over(
                    datafusion.expr.Window(
                        partition_by=partitioning,
                        order_by=[
                            col(s1start_s2end).sort(),
                            col(is_s1).sort(
                                ascending=(overlap_filter == FilterOp.Strict)
                            ),
                        ],
                    )
                )
                .alias(starts),
                datafusion.functions.sum(col(is_s1))
                .over(
                    datafusion.expr.Window(
                        partition_by=partitioning,
                        order_by=[
                            col(s1end_s2start).sort(),
                            col(is_s1).sort(
                                ascending=(overlap_filter == FilterOp.Weak)
                            ),
                        ],
                    )
                )
                .alias(ends),
            ]
            + on_cols
        )
    )
    df = df.filter(col(is_s1) == 0)
    df = df.select(
        *(
            [
                col(contig).alias(cols1[0] + suff),
                col(s1end_s2start).alias(cols1[1] + suff),
                col(s1start_s2end).alias(cols1[2] + suff),
            ]
            + on_cols
            + [(col(starts) - col(ends)).alias(count)]
        )
    )

    return convert_result(df, output_type, streaming)

def coverage(
    df1: Union[str, pl.DataFrame, pl.LazyFrame, pd.DataFrame],
    df2: Union[str, pl.DataFrame, pl.LazyFrame, pd.DataFrame],
    overlap_filter: FilterOp = FilterOp.Strict,
    suffixes: tuple[str, str] = ("_1", "_2"),
    on_cols: Union[list[str], None] = None,
    cols1: Union[list[str], None] = ["chrom", "start", "end"],
    cols2: Union[list[str], None] = ["chrom", "start", "end"],
    output_type: str = "polars.LazyFrame",
    streaming: bool = False,
    read_options: Union[ReadOptions, None] = None,
) -> Union[pl.LazyFrame, pl.DataFrame, pd.DataFrame, datafusion.DataFrame]:
    """
    Calculate intervals coverage.
    Bioframe inspired API.

    Parameters:
        df1: Can be a path to a file, a polars DataFrame, or a pandas DataFrame or a registered table (see [register_vcf](api.md#polars_bio.register_vcf)). CSV with a header, BED and Parquet are supported.
        df2: Can be a path to a file, a polars DataFrame, or a pandas DataFrame or a registered table. CSV with a header, BED  and Parquet are supported.
        overlap_filter: FilterOp, optional. The type of overlap to consider(Weak or Strict). Strict for **0-based**, Weak for **1-based** coordinate systems.
        cols1: The names of columns containing the chromosome, start and end of the
            genomic intervals, provided separately for each set.
        cols2:  The names of columns containing the chromosome, start and end of the
            genomic intervals, provided separately for each set.
        suffixes: Suffixes for the columns of the two overlapped sets.
        on_cols: List of additional column names to join on. default is None.
        output_type: Type of the output. default is "polars.LazyFrame", "polars.DataFrame", or "pandas.DataFrame" or "datafusion.DataFrame" are also supported.
        streaming: **EXPERIMENTAL** If True, use Polars [streaming](features.md#streaming) engine.
        read_options: Additional options for reading the input files.


    Returns:
        **polars.LazyFrame** or polars.DataFrame or pandas.DataFrame of the overlapping intervals.

    Note:
        The default output format, i.e. [LazyFrame](https://docs.pola.rs/api/python/stable/reference/lazyframe/index.html), is recommended for large datasets as it supports output streaming and lazy evaluation.
        This enables efficient processing of large datasets without loading the entire output dataset into memory.

    Example:

    Todo:
        Support for on_cols.
    """

    _validate_overlap_input(cols1, cols2, on_cols, suffixes, output_type, how="inner")

    cols1 = DEFAULT_INTERVAL_COLUMNS if cols1 is None else cols1
    cols2 = DEFAULT_INTERVAL_COLUMNS if cols2 is None else cols2
    range_options = RangeOptions(
        range_op=RangeOp.Coverage,
        filter_op=overlap_filter,
        suffixes=suffixes,
        columns_1=cols1,
        columns_2=cols2,
        streaming=streaming,
    )
    return range_operation(df2, df1, range_options, output_type, ctx, read_options)

def describe_vcf(path: str) -> pl.DataFrame:
    """
    Describe VCF INFO schema.

    Parameters:
        path: The path to the VCF file.

    !!! Example
        ```python
        import polars_bio as pb
        vcf_1 = "gs://gcp-public-data--gnomad/release/4.1/genome_sv/gnomad.v4.1.sv.sites.vcf.gz"
        pb.describe_vcf(vcf_1).sort("name").limit(5)
        ```

        ```shell
            shape: (5, 3)
        ┌───────────┬─────────┬──────────────────────────────────────────────────────────────────────────────────────┐
        │ name      ┆ type    ┆ description                                                                          │
        │ ---       ┆ ---     ┆ ---                                                                                  │
        │ str       ┆ str     ┆ str                                                                                  │
        ╞═══════════╪═════════╪══════════════════════════════════════════════════════════════════════════════════════╡
        │ AC        ┆ Integer ┆ Number of non-reference alleles observed (biallelic sites only).                     │
        │ AC_XX     ┆ Integer ┆ Number of non-reference XX alleles observed (biallelic sites only).                  │
        │ AC_XY     ┆ Integer ┆ Number of non-reference XY alleles observed (biallelic sites only).                  │
        │ AC_afr    ┆ Integer ┆ Number of non-reference African-American alleles observed (biallelic sites only).    │
        │ AC_afr_XX ┆ Integer ┆ Number of non-reference African-American XX alleles observed (biallelic sites only). │
        └───────────┴─────────┴──────────────────────────────────────────────────────────────────────────────────────┘


        ```
    """
    return py_describe_vcf(ctx, path).to_polars()

def from_polars(name: str, df: Union[pl.DataFrame, pl.LazyFrame]) -> None:
    """
    Register a Polars DataFrame as a DataFusion table.

    Parameters:
        name: The name of the table.
        df: The Polars DataFrame.
    !!! Example
        ```python
        import polars as pl
        import polars_bio as pb
        df = pl.DataFrame({
            "a": [1, 2, 3],
            "b": [4, 5, 6]
        })
        pb.from_polars("test_df", df)
        pb.sql("SELECT * FROM test_df").collect()
        ```
        ```shell
        3rows [00:00, 2978.91rows/s]
        shape: (3, 2)
        ┌─────┬─────┐
        │ a   ┆ b   │
        │ --- ┆ --- │
        │ i64 ┆ i64 │
        ╞═════╪═════╡
        │ 1   ┆ 4   │
        │ 2   ┆ 5   │
        │ 3   ┆ 6   │
        └─────┴─────┘
        ```
    """
    reader = (
        df.to_arrow()
        if isinstance(df, pl.DataFrame)
        else df.collect().to_arrow().to_reader()
    )
    py_from_polars(ctx, name, reader)