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# Source code for astropy.table.pprint

    # Licensed under a 3-clause BSD style license - see LICENSE.rst

    import fnmatch
    import os
    import re
    import sys

    import numpy as np

    from astropy import log
    from astropy.utils.console import Getch, color_print, conf, terminal_size
    from astropy.utils.data_info import dtype_info_name

    __all__ = []

    def default_format_func(format_, val):
        if isinstance(val, bytes):
            return val.decode("utf-8", errors="replace")
        else:
            return str(val)

    # The first three functions are helpers for _auto_format_func

    def _use_str_for_masked_values(format_func):
        """Wrap format function to trap masked values.

        String format functions and most user functions will not be able to deal
        with masked values, so we wrap them to ensure they are passed to str().
        """
        return lambda format_, val: (
            str(val) if val is np.ma.masked else format_func(format_, val)
        )

    def _possible_string_format_functions(format_):
        """Iterate through possible string-derived format functions.

        A string can either be a format specifier for the format built-in,
        a new-style format string, or an old-style format string.
        """
        yield lambda format_, val: format(val, format_)
        yield lambda format_, val: format_.format(val)
        yield lambda format_, val: format_ % val
        yield lambda format_, val: format_.format(**{k: val[k] for k in val.dtype.names})

    def get_auto_format_func(
        col=None, possible_string_format_functions=_possible_string_format_functions
    ):
        """
        Return a wrapped ``auto_format_func`` function which is used in
        formatting table columns.  This is primarily an internal function but
        gets used directly in other parts of astropy, e.g. `astropy.io.ascii`.

        Parameters
        ----------
        col_name : object, optional
            Hashable object to identify column like id or name. Default is None.

        possible_string_format_functions : func, optional
            Function that yields possible string formatting functions
            (defaults to internal function to do this).

        Returns
        -------
        Wrapped ``auto_format_func`` function
        """

        def _auto_format_func(format_, val):
            """Format ``val`` according to ``format_`` for a plain format specifier,
            old- or new-style format strings, or using a user supplied function.
            More importantly, determine and cache (in _format_funcs) a function
            that will do this subsequently.  In this way this complicated logic is
            only done for the first value.

            Returns the formatted value.
            """
            if format_ is None:
                return default_format_func(format_, val)

            if format_ in col.info._format_funcs:
                return col.info._format_funcs[format_](format_, val)

            if callable(format_):
                format_func = lambda format_, val: format_(val)  # noqa: E731
                try:
                    out = format_func(format_, val)
                    if not isinstance(out, str):
                        raise ValueError(
                            "Format function for value {} returned {} "
                            "instead of string type".format(val, type(val))
                        )
                except Exception as err:
                    # For a masked element, the format function call likely failed
                    # to handle it.  Just return the string representation for now,
                    # and retry when a non-masked value comes along.
                    if val is np.ma.masked:
                        return str(val)

                    raise ValueError(f"Format function for value {val} failed.") from err
                # If the user-supplied function handles formatting masked elements, use
                # it directly.  Otherwise, wrap it in a function that traps them.
                try:
                    format_func(format_, np.ma.masked)
                except Exception:
                    format_func = _use_str_for_masked_values(format_func)
            else:
                # For a masked element, we cannot set string-based format functions yet,
                # as all tests below will fail.  Just return the string representation
                # of masked for now, and retry when a non-masked value comes along.
                if val is np.ma.masked:
                    return str(val)

                for format_func in possible_string_format_functions(format_):
                    try:
                        # Does this string format method work?
                        out = format_func(format_, val)
                        # Require that the format statement actually did something.
                        if out == format_:
                            raise ValueError("the format passed in did nothing.")
                    except Exception:
                        continue
                    else:
                        break
                else:
                    # None of the possible string functions passed muster.
                    raise ValueError(
                        f"unable to parse format string {format_} for its column."
                    )

                # String-based format functions will fail on masked elements;
                # wrap them in a function that traps them.
                format_func = _use_str_for_masked_values(format_func)

            col.info._format_funcs[format_] = format_func
            return out

        return _auto_format_func

    def _get_pprint_include_names(table):
        """Get the set of names to show in pprint from the table pprint_include_names
        and pprint_exclude_names attributes.

        These may be fnmatch unix-style globs.
        """

        def get_matches(name_globs, default):
            match_names = set()
            if name_globs:  # For None or () use the default
                for name in table.colnames:
                    for name_glob in name_globs:
                        if fnmatch.fnmatch(name, name_glob):
                            match_names.add(name)
                            break
            else:
                match_names.update(default)
            return match_names

        include_names = get_matches(table.pprint_include_names(), table.colnames)
        exclude_names = get_matches(table.pprint_exclude_names(), [])

        return include_names - exclude_names

    class TableFormatter:
        @staticmethod
        def _get_pprint_size(max_lines=None, max_width=None):
            """Get the output size (number of lines and character width) for Column and
            Table pformat/pprint methods.

            If no value of ``max_lines`` is supplied then the height of the
            screen terminal is used to set ``max_lines``.  If the terminal
            height cannot be determined then the default will be determined
            using the ``astropy.table.conf.max_lines`` configuration item. If a
            negative value of ``max_lines`` is supplied then there is no line
            limit applied.

            The same applies for max_width except the configuration item is
            ``astropy.table.conf.max_width``.

            Parameters
            ----------
            max_lines : int or None
                Maximum lines of output (header + data rows)

            max_width : int or None
                Maximum width (characters) output

            Returns
            -------
            max_lines, max_width : int

            """
            # Declare to keep static type checker happy.
            lines = None
            width = None

            if max_lines is None:
                max_lines = conf.max_lines

            if max_width is None:
                max_width = conf.max_width

            if max_lines is None or max_width is None:
                lines, width = terminal_size()

            if max_lines is None:
                max_lines = lines
            elif max_lines < 0:
                max_lines = sys.maxsize
            if max_lines < 8:
                max_lines = 8

            if max_width is None:
                max_width = width
            elif max_width < 0:
                max_width = sys.maxsize
            if max_width < 10:
                max_width = 10

            return max_lines, max_width

        def _pformat_col(
            self,
            col,
            max_lines=None,
            show_name=True,
            show_unit=None,
            show_dtype=False,
            show_length=None,
            html=False,
            align=None,
        ):
            """Return a list of formatted string representation of column values.

            Parameters
            ----------
            max_lines : int
                Maximum lines of output (header + data rows)

            show_name : bool
                Include column name. Default is True.

            show_unit : bool
                Include a header row for unit.  Default is to show a row
                for units only if one or more columns has a defined value
                for the unit.

            show_dtype : bool
                Include column dtype. Default is False.

            show_length : bool
                Include column length at end.  Default is to show this only
                if the column is not shown completely.

            html : bool
                Output column as HTML

            align : str
                Left/right alignment of columns. Default is '>' (right) for all
                columns. Other allowed values are '<', '^', and '0=' for left,
                centered, and 0-padded, respectively.

            Returns
            -------
            lines : list
                List of lines with formatted column values

            outs : dict
                Dict which is used to pass back additional values
                defined within the iterator.

            """
            if show_unit is None:
                show_unit = col.info.unit is not None

            outs = {}  # Some values from _pformat_col_iter iterator that are needed here
            col_strs_iter = self._pformat_col_iter(
                col,
                max_lines,
                show_name=show_name,
                show_unit=show_unit,
                show_dtype=show_dtype,
                show_length=show_length,
                outs=outs,
            )

            # Replace tab and newline with text representations so they display nicely.
            # Newline in particular is a problem in a multicolumn table.
            col_strs = [
                val.replace("\t", "\\t").replace("\n", "\\n") for val in col_strs_iter
            ]
            if len(col_strs) > 0:
                col_width = max(len(x) for x in col_strs)

            if html:
                from astropy.utils.xml.writer import xml_escape

                n_header = outs["n_header"]
                for i, col_str in enumerate(col_strs):
                    # _pformat_col output has a header line '----' which is not needed here
                    if i == n_header - 1:
                        continue
                    td = "th" if i < n_header else "td"
                    val = f"<{td}>{xml_escape(col_str.strip())}</{td}>"
                    row = "<tr>" + val + "</tr>"
                    if i < n_header:
                        row = "<thead>" + row + "</thead>"
                    col_strs[i] = row

                if n_header > 0:
                    # Get rid of '---' header line
                    col_strs.pop(n_header - 1)
                col_strs.insert(0, "<table>")
                col_strs.append("</table>")

            # Now bring all the column string values to the same fixed width
            else:
                col_width = max(len(x) for x in col_strs) if col_strs else 1

                # Center line header content and generate dashed headerline
                for i in outs["i_centers"]:
                    col_strs[i] = col_strs[i].center(col_width)
                if outs["i_dashes"] is not None:
                    col_strs[outs["i_dashes"]] = "-" * col_width

                # Format columns according to alignment.  `align` arg has precedent, otherwise
                # use `col.format` if it starts as a legal alignment string.  If neither applies
                # then right justify.
                re_fill_align = re.compile(r"(?P<fill>.?)(?P<align>[<^>=])")
                match = None
                if align:
                    # If there is an align specified then it must match
                    match = re_fill_align.match(align)
                    if not match:
                        raise ValueError(
                            "column align must be one of '<', '^', '>', or '='"
                        )
                elif isinstance(col.info.format, str):
                    # col.info.format need not match, in which case rjust gets used
                    match = re_fill_align.match(col.info.format)

                if match:
                    fill_char = match.group("fill")
                    align_char = match.group("align")
                    if align_char == "=":
                        if fill_char != "0":
                            raise ValueError("fill character must be '0' for '=' align")
                        # str.zfill gets used which does not take fill char arg
                        fill_char = ""
                else:
                    fill_char = ""
                    align_char = ">"

                justify_methods = {"<": "ljust", "^": "center", ">": "rjust", "=": "zfill"}
                justify_method = justify_methods[align_char]
                justify_args = (col_width, fill_char) if fill_char else (col_width,)

                for i, col_str in enumerate(col_strs):
                    col_strs[i] = getattr(col_str, justify_method)(*justify_args)

            if outs["show_length"]:
                col_strs.append(f"Length = {len(col)} rows")

            return col_strs, outs

        def _name_and_structure(self, name, dtype, sep=" "):
            """Format a column name, including a possible structure.

            Normally, just returns the name, but if it has a structured dtype,
            will add the parts in between square brackets.  E.g.,
            "name [f0, f1]" or "name [f0[sf0, sf1], f1]".
            """
            if dtype is None or dtype.names is None:
                return name

            structure = ", ".join(
                [
                    self._name_and_structure(name, dt, sep="")
                    for name, (dt, _) in dtype.fields.items()
                ]
            )
            return f"{name}{sep}[{structure}]"

        def _pformat_col_iter(
            self,
            col,
            max_lines,
            show_name,
            show_unit,
            outs,
            show_dtype=False,
            show_length=None,
        ):
            """Iterator which yields formatted string representation of column values.

            Parameters
            ----------
            max_lines : int
                Maximum lines of output (header + data rows)

            show_name : bool
                Include column name. Default is True.

            show_unit : bool
                Include a header row for unit.  Default is to show a row
                for units only if one or more columns has a defined value
                for the unit.

            outs : dict
                Must be a dict which is used to pass back additional values
                defined within the iterator.

            show_dtype : bool
                Include column dtype. Default is False.

            show_length : bool
                Include column length at end.  Default is to show this only
                if the column is not shown completely.
            """
            max_lines, _ = self._get_pprint_size(max_lines, -1)
            dtype = getattr(col, "dtype", None)
            multidims = getattr(col, "shape", [0])[1:]
            if multidims:
                multidim0 = tuple(0 for n in multidims)
                multidim1 = tuple(n - 1 for n in multidims)
                multidims_all_ones = np.prod(multidims) == 1
                multidims_has_zero = 0 in multidims

            i_dashes = None
            i_centers = []  # Line indexes where content should be centered
            n_header = 0
            if show_name:
                i_centers.append(n_header)
                # Get column name (or 'None' if not set)
                col_name = str(col.info.name)
                n_header += 1
                yield self._name_and_structure(col_name, dtype)
            if show_unit:
                i_centers.append(n_header)
                n_header += 1
                yield str(col.info.unit or "")
            if show_dtype:
                i_centers.append(n_header)
                n_header += 1
                if dtype is not None:
                    col_dtype = dtype_info_name((dtype, multidims))
                else:
                    col_dtype = col.__class__.__qualname__ or "object"
                yield col_dtype
            if show_unit or show_name or show_dtype:
                i_dashes = n_header
                n_header += 1
                yield "---"

            max_lines -= n_header
            n_print2 = max_lines // 2
            n_rows = len(col)

            # This block of code is responsible for producing the function that
            # will format values for this column.  The ``format_func`` function
            # takes two args (col_format, val) and returns the string-formatted
            # version.  Some points to understand:
            #
            # - col_format could itself be the formatting function, so it will
            #    actually end up being called with itself as the first arg.  In
            #    this case the function is expected to ignore its first arg.
            #
            # - auto_format_func is a function that gets called on the first
            #    column value that is being formatted.  It then determines an
            #    appropriate formatting function given the actual value to be
            #    formatted.  This might be deterministic or it might involve
            #    try/except.  The latter allows for different string formatting
            #    options like %f or {:5.3f}.  When auto_format_func is called it:

            #    1. Caches the function in the _format_funcs dict so for subsequent
            #       values the right function is called right away.
            #    2. Returns the formatted value.
            #
            # - possible_string_format_functions is a function that yields a
            #    succession of functions that might successfully format the
            #    value.  There is a default, but Mixin methods can override this.
            #    See Quantity for an example.
            #
            # - get_auto_format_func() returns a wrapped version of auto_format_func
            #    with the column id and possible_string_format_functions as
            #    enclosed variables.
            col_format = col.info.format or getattr(col.info, "default_format", None)
            pssf = (
                getattr(col.info, "possible_string_format_functions", None)
                or _possible_string_format_functions
            )
            auto_format_func = get_auto_format_func(col, pssf)
            format_func = col.info._format_funcs.get(col_format, auto_format_func)

            if len(col) > max_lines:
                if show_length is None:
                    show_length = True
                i0 = n_print2 - (1 if show_length else 0)
                i1 = n_rows - n_print2 - max_lines % 2
                indices = np.concatenate(
                    [np.arange(0, i0 + 1), np.arange(i1 + 1, len(col))]
                )
            else:
                i0 = -1
                indices = np.arange(len(col))

            def format_col_str(idx):
                if multidims:
                    # Prevents columns like Column(data=[[(1,)],[(2,)]], name='a')
                    # with shape (n,1,...,1) from being printed as if there was
                    # more than one element in a row
                    if multidims_all_ones:
                        return format_func(col_format, col[(idx,) + multidim0])
                    elif multidims_has_zero:
                        # Any zero dimension means there is no data to print
                        return ""
                    else:
                        left = format_func(col_format, col[(idx,) + multidim0])
                        right = format_func(col_format, col[(idx,) + multidim1])
                        return f"{left} .. {right}"
                else:
                    return format_func(col_format, col[idx])

            # Add formatted values if within bounds allowed by max_lines
            for idx in indices:
                if idx == i0:
                    yield "..."
                else:
                    try:
                        yield format_col_str(idx)
                    except ValueError:
                        raise ValueError(
                            'Unable to parse format string "{}" for entry "{}" '
                            'in column "{}"'.format(col_format, col[idx], col.info.name)
                        )

            outs["show_length"] = show_length
            outs["n_header"] = n_header
            outs["i_centers"] = i_centers
            outs["i_dashes"] = i_dashes

        def _pformat_table(
            self,
            table,
            max_lines=None,
            max_width=None,
            show_name=True,
            show_unit=None,
            show_dtype=False,
            html=False,
            tableid=None,
            tableclass=None,
            align=None,
        ):
            """Return a list of lines for the formatted string representation of
            the table.

            Parameters
            ----------
            max_lines : int or None
                Maximum number of rows to output

            max_width : int or None
                Maximum character width of output

            show_name : bool
                Include a header row for column names. Default is True.

            show_unit : bool
                Include a header row for unit.  Default is to show a row
                for units only if one or more columns has a defined value
                for the unit.

            show_dtype : bool
                Include a header row for column dtypes. Default is to False.

            html : bool
                Format the output as an HTML table. Default is False.

            tableid : str or None
                An ID tag for the table; only used if html is set.  Default is
                "table{id}", where id is the unique integer id of the table object,
                id(table)

            tableclass : str or list of str or None
                CSS classes for the table; only used if html is set.  Default is
                none

            align : str or list or tuple
                Left/right alignment of columns. Default is '>' (right) for all
                columns. Other allowed values are '<', '^', and '0=' for left,
                centered, and 0-padded, respectively. A list of strings can be
                provided for alignment of tables with multiple columns.

            Returns
            -------
            rows : list
                Formatted table as a list of strings

            outs : dict
                Dict which is used to pass back additional values
                defined within the iterator.

            """
            # "Print" all the values into temporary lists by column for subsequent
            # use and to determine the width
            max_lines, max_width = self._get_pprint_size(max_lines, max_width)

            if show_unit is None:
                show_unit = any(col.info.unit for col in table.columns.values())

            # Coerce align into a correctly-sized list of alignments (if possible)
            n_cols = len(table.columns)
            if align is None or isinstance(align, str):
                align = [align] * n_cols

            elif isinstance(align, (list, tuple)):
                if len(align) != n_cols:
                    raise ValueError(
                        "got {} alignment values instead of "
                        "the number of columns ({})".format(len(align), n_cols)
                    )
            else:
                raise TypeError(
                    "align keyword must be str or list or tuple (got {})".format(
                        type(align)
                    )
                )

            # Process column visibility from table pprint_include_names and
            # pprint_exclude_names attributes and get the set of columns to show.
            pprint_include_names = _get_pprint_include_names(table)

            cols = []
            outs = None  # Initialize so static type checker is happy
            for align_, col in zip(align, table.columns.values()):
                if col.info.name not in pprint_include_names:
                    continue

                lines, outs = self._pformat_col(
                    col,
                    max_lines,
                    show_name=show_name,
                    show_unit=show_unit,
                    show_dtype=show_dtype,
                    align=align_,
                )
                if outs["show_length"]:
                    lines = lines[:-1]
                cols.append(lines)

            if not cols:
                return ["<No columns>"], {"show_length": False}

            # Use the values for the last column since they are all the same
            n_header = outs["n_header"]

            n_rows = len(cols[0])

            def outwidth(cols):
                return sum(len(c[0]) for c in cols) + len(cols) - 1

            dots_col = ["..."] * n_rows
            middle = len(cols) // 2
            while outwidth(cols) > max_width:
                if len(cols) == 1:
                    break
                if len(cols) == 2:
                    cols[1] = dots_col
                    break
                if cols[middle] is dots_col:
                    cols.pop(middle)
                    middle = len(cols) // 2
                cols[middle] = dots_col

            # Now "print" the (already-stringified) column values into a
            # row-oriented list.
            rows = []
            if html:
                from astropy.utils.xml.writer import xml_escape

                if tableid is None:
                    tableid = f"table{id(table)}"

                if tableclass is not None:
                    if isinstance(tableclass, list):
                        tableclass = " ".join(tableclass)
                    rows.append(f'<table id="{tableid}" class="{tableclass}">')
                else:
                    rows.append(f'<table id="{tableid}">')

                for i in range(n_rows):
                    # _pformat_col output has a header line '----' which is not needed here
                    if i == n_header - 1:
                        continue
                    td = "th" if i < n_header else "td"
                    vals = (f"<{td}>{xml_escape(col[i].strip())}</{td}>" for col in cols)
                    row = "<tr>" + "".join(vals) + "</tr>"
                    if i < n_header:
                        row = "<thead>" + row + "</thead>"
                    rows.append(row)
                rows.append("</table>")
            else:
                for i in range(n_rows):
                    row = " ".join(col[i] for col in cols)
                    rows.append(row)

            return rows, outs

        def _more_tabcol(
            self,
            tabcol,
            max_lines=None,
            max_width=None,
            show_name=True,
            show_unit=None,
            show_dtype=False,
        ):
            """Interactive "more" of a table or column.

            Parameters
            ----------
            max_lines : int or None
                Maximum number of rows to output

            max_width : int or None
                Maximum character width of output

            show_name : bool
                Include a header row for column names. Default is True.

            show_unit : bool
                Include a header row for unit.  Default is to show a row
                for units only if one or more columns has a defined value
                for the unit.

            show_dtype : bool
                Include a header row for column dtypes. Default is False.
            """
            allowed_keys = "f br<>qhpn"

            # Count the header lines
            n_header = 0
            if show_name:
                n_header += 1
            if show_unit:
                n_header += 1
            if show_dtype:
                n_header += 1
            if show_name or show_unit or show_dtype:
                n_header += 1

            # Set up kwargs for pformat call.  Only Table gets max_width.
            kwargs = dict(
                max_lines=-1,
                show_name=show_name,
                show_unit=show_unit,
                show_dtype=show_dtype,
            )
            if hasattr(tabcol, "columns"):  # tabcol is a table
                kwargs["max_width"] = max_width

            # If max_lines is None (=> query screen size) then increase by 2.
            # This is because get_pprint_size leaves 6 extra lines so that in
            # ipython you normally see the last input line.
            max_lines1, max_width = self._get_pprint_size(max_lines, max_width)
            if max_lines is None:
                max_lines1 += 2
            delta_lines = max_lines1 - n_header

            # Set up a function to get a single character on any platform
            inkey = Getch()

            i0 = 0  # First table/column row to show
            showlines = True
            while True:
                i1 = i0 + delta_lines  # Last table/col row to show
                if showlines:  # Don't always show the table (e.g. after help)
                    try:
                        os.system("cls" if os.name == "nt" else "clear")
                    except Exception:
                        pass  # No worries if clear screen call fails
                    lines = tabcol[i0:i1].pformat(**kwargs)
                    colors = (
                        "red" if i < n_header else "default" for i in range(len(lines))
                    )
                    for color, line in zip(colors, lines):
                        color_print(line, color)
                showlines = True
                print()
                print("-- f, <space>, b, r, p, n, <, >, q h (help) --", end=" ")
                # Get a valid key
                while True:
                    try:
                        key = inkey().lower()
                    except Exception:
                        print("\n")
                        log.error(
                            "Console does not support getting a character"
                            " as required by more().  Use pprint() instead."
                        )
                        return
                    if key in allowed_keys:
                        break
                print(key)

                if key.lower() == "q":
                    break
                elif key == " " or key == "f":
                    i0 += delta_lines
                elif key == "b":
                    i0 = i0 - delta_lines
                elif key == "r":
                    pass
                elif key == "<":
                    i0 = 0
                elif key == ">":
                    i0 = len(tabcol)
                elif key == "p":
                    i0 -= 1
                elif key == "n":
                    i0 += 1
                elif key == "h":
                    showlines = False
                    print(
                        """
        Browsing keys:
           f, <space> : forward one page
           b : back one page
           r : refresh same page
           n : next row
           p : previous row
           < : go to beginning
           > : go to end
           q : quit browsing
           h : print this help""",
                        end=" ",
                    )
                if i0 < 0:
                    i0 = 0
                if i0 >= len(tabcol) - delta_lines:
                    i0 = len(tabcol) - delta_lines
                print("\n")