use std::collections::VecDeque;
use std::io::{Read, Seek};
use polars_buffer::Buffer;
use polars_error::{PolarsResult, polars_err};
use polars_utils::bool::UnsafeBool;
use super::super::super::IpcField;
use super::super::deserialize::{read, skip};
use super::super::read_basic::*;
use super::super::{Compression, Dictionaries, IpcBuffer, Node, Version};
use crate::array::ListArray;
use crate::datatypes::ArrowDataType;
use crate::io::ipc::read::array::{try_get_array_length, try_get_field_node};
use crate::offset::{Offset, OffsetsBuffer};
#[allow(clippy::too_many_arguments)]
pub fn read_list<O: Offset, R: Read + Seek>(
field_nodes: &mut VecDeque<Node>,
variadic_buffer_counts: &mut VecDeque<usize>,
dtype: ArrowDataType,
ipc_field: &IpcField,
buffers: &mut VecDeque<IpcBuffer>,
reader: &mut R,
dictionaries: &Dictionaries,
block_offset: u64,
is_little_endian: bool,
compression: Option<Compression>,
limit: Option<usize>,
version: Version,
scratch: &mut Vec<u8>,
checked: UnsafeBool,
) -> PolarsResult<ListArray<O>>
where
Vec<u8>: TryInto<O::Bytes>,
{
let field_node = try_get_field_node(field_nodes, &dtype)?;
let validity = read_validity(
buffers,
field_node,
reader,
block_offset,
is_little_endian,
compression,
limit,
scratch,
)?;
let length = try_get_array_length(field_node, limit)?;
let offsets = read_buffer::<O, _>(
buffers,
1 + length,
reader,
block_offset,
is_little_endian,
compression,
scratch,
)
.or_else(|_| PolarsResult::Ok(Buffer::<O>::from(vec![O::default()])))?;
let last_offset = offsets.last().unwrap().to_usize();
let field = ListArray::<O>::get_child_field(&dtype);
let values = read(
field_nodes,
variadic_buffer_counts,
field,
&ipc_field.fields[0],
buffers,
reader,
dictionaries,
block_offset,
is_little_endian,
compression,
Some(last_offset),
version,
scratch,
checked,
)?;
let offsets = if *checked {
offsets.try_into()?
} else {
unsafe { OffsetsBuffer::new_unchecked(offsets) }
};
ListArray::try_new(dtype, offsets, values, validity)
}
pub fn skip_list<O: Offset>(
field_nodes: &mut VecDeque<Node>,
dtype: &ArrowDataType,
buffers: &mut VecDeque<IpcBuffer>,
variadic_buffer_counts: &mut VecDeque<usize>,
) -> PolarsResult<()> {
let _ = field_nodes.pop_front().ok_or_else(|| {
polars_err!(
oos = "IPC: unable to fetch the field for list. The file or stream is corrupted."
)
})?;
let _ = buffers
.pop_front()
.ok_or_else(|| polars_err!(oos = "IPC: missing validity buffer."))?;
let _ = buffers
.pop_front()
.ok_or_else(|| polars_err!(oos = "IPC: missing offsets buffer."))?;
let dtype = ListArray::<O>::get_child_type(dtype);
skip(field_nodes, dtype, buffers, variadic_buffer_counts)
}