#!/usr/bin/env python
#
# Copyright 2016 Google Inc. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Extract cmap data from mti phase 3 spreadsheet."""

import argparse
from os import path
import sys

from nototools import cmap_data
from nototools import tool_utils
from nototools import unicode_data

# exceptions for script codes that are not actual script codes, but
# our own custom keys.
_SCRIPT_KEY_NAMES = [("SYM2", "Symbols2")]


def get_script_for_name(script_name):
    starred = False
    added = False
    if script_name[-1] == "*":
        starred = True
        script_name = script_name[:-1]
        added = True
    if script_name in ["LGC", "MONO", "MUSIC", "SYM2"]:
        return script_name, starred

    for k, name in _SCRIPT_KEY_NAMES:
        if script_name == name:
            return k, starred

    code = unicode_data.script_code(script_name)
    if code == "Zzzz":
        raise ValueError('cannot identify script for "%s"' % script_name)
    return code, starred


def get_script_to_cmaps(csvdata):
    # Roll our own parse, the data is simple... well, mostly.
    # Google sheets inconsistently puts ^Z in first empty cell in a column.
    # Asterisks mark codepoints that are 'ok for fallback', an asterisk on
    # the header means the font has been checked for fallback.  It is
    # illegal to mark codepoints as ok for fallback if the header is not
    # so marked, but ok to mark the header as checked with no codepoints
    # ok for fallback.
    # Plus ('+') marks additions by MTI above what we'd requested because
    # they've found a requirement.  We flag these and add them to our
    # requirements.  We're not set up to preserve these and changing that
    # would be difficult at this point, so we just note the addition.

    """This returns a map from 'script' to a tuple of cmap, xcmap where
    xcmap is None if the header has not been checked, and contains the
    marked codepoints otherwise (and might be empty)."""

    header = None
    data = None
    xdata = None
    for n, r in enumerate(csvdata.splitlines()):
        r = r.strip()
        if not r:
            continue
        rowdata = r.split(",")
        if not header:
            header, starred = zip(*[get_script_for_name(name) for name in rowdata])
            ncols = len(header)
            data = [set() for _ in range(ncols)]
            xdata = [(set() if star else None) for star in starred]
            continue

        if len(rowdata) != ncols:
            raise ValueError(
                'row %d had %d cols but expected %d:\n"%s"'
                % (n, len(rowdata), ncols, r)
            )
        for i, v in enumerate(rowdata):
            v = v.strip(" \n\t")
            if not v or v == u"\u001a":
                continue
            try:
                if v[-1] == "*":
                    xdata[i].add(int(v[:-1], 16))
                elif v[-1] == "+":
                    print("> %s added %s" % (header[i], v[:-1]))
                    data[i].add(int(v[:-1], 16))
                else:
                    data[i].add(int(v, 16))
            except:
                raise ValueError('error in col %d of row %d: "%s"' % (i, n, v))
    return {script: (cmap, xcmap) for script, cmap, xcmap in zip(header, data, xdata)}


def cmap_data_from_csv(csvdata, scripts=None, exclude_scripts=None, infile=None):
    args = [("infile", infile)] if infile else None
    metadata = cmap_data.create_metadata("mti_cmap_data", args)
    script_to_cmaps = get_script_to_cmaps(csvdata)
    if scripts or exclude_scripts:
        script_list = script_to_cmaps.keys()
        for script in script_list:
            if scripts and script not in scripts:
                del script_to_cmaps[script]
            elif exclude_scripts and script in exclude_scripts:
                del script_to_cmaps[script]
    tabledata = cmap_data.create_table_from_map(script_to_cmaps)
    return cmap_data.CmapData(metadata, tabledata)


def cmap_data_from_csv_file(csvfile, scripts=None, exclude_scripts=None):
    with open(csvfile, "r") as f:
        csvdata = f.read()
    return cmap_data_from_csv(csvdata, scripts, exclude_scripts, csvfile)


def csv_to_xml(csv_file, xml_file, scripts, exclude_scripts):
    cmapdata = cmap_data_from_csv_file(csv_file, scripts, exclude_scripts)
    if xml_file:
        sys.stderr.write("writing %s\n" % xml_file)
        cmap_data.write_cmap_data_file(cmapdata, xml_file, pretty=True)
    else:
        print(cmap_data.write_cmap_data(cmapdata, pretty=True))


def _script_to_name(script):
    for k, name in _SCRIPT_KEY_NAMES:
        if script == k:
            return name

    try:
        return unicode_data.human_readable_script_name(script)
    except KeyError:
        return script


def csv_from_cmap_data(data, scripts, exclude_scripts):
    script_to_rowdata = cmap_data.create_map_from_table(data.table)
    cols = []
    max_lines = 0
    num_cells = 0
    for script in sorted(script_to_rowdata, key=lambda s: _script_to_name(s).lower()):
        if scripts and script not in scripts:
            continue
        if exclude_scripts and script in exclude_scripts:
            continue

        rd = script_to_rowdata[script]
        star = int(getattr(rd, "xcount", -1)) != -1
        col = ['"%s%s"' % (_script_to_name(script), "*" if star else "")]
        cps = tool_utils.parse_int_ranges(rd.ranges)
        xranges = getattr(rd, "xranges", None)
        if xranges is not None:
            xcps = frozenset(tool_utils.parse_int_ranges(xranges))
            cps |= xcps
        else:
            xcps = frozenset()
        num_cells += len(cps)
        col.extend("%04X%s" % (cp, "*" if cp in xcps else "") for cp in sorted(cps))
        cols.append(col)
        max_lines = max(max_lines, len(col))

    num_cols = len(cols)
    num_cells += num_cols  # headers are not empty
    all_cells = num_cols * max_lines
    fmt = "Columns: %d\nRows: %d\nNon-empty cells: %d\nCells: %d"
    sys.stderr.write(fmt % (num_cols, max_lines, num_cells, all_cells) + "\n")
    cmap_lines = []
    cmap_lines.append(",".join(col[0] for col in cols))
    for i in range(1, max_lines):
        cmap_lines.append(",".join(col[i] if i < len(col) else "" for col in cols))
    return "\n".join(cmap_lines)


def xml_to_csv(xml_file, csv_file, scripts, exclude_scripts):
    data = cmap_data.read_cmap_data_file(xml_file)
    csv_data = csv_from_cmap_data(data, scripts, exclude_scripts)
    if csv_file:
        with open(csv_file, "w") as f:
            f.write(csv_data)
    else:
        print(csv_data)


def _check_scripts(scripts):
    """Return True if all scripts are known (pseudo) codes."""
    have_unknown = False
    if scripts:
        all_scripts = unicode_data.all_scripts()
        all_scripts = all_scripts | {
            "CJK",
            "EXCL",
            "LGC",
            "MONO",
            "MUSIC",
            "SYM2",
            "Zsye",
        }
        for s in scripts:
            if s not in all_scripts:
                sys.stderr.write("unknown script:\n", s)
                have_unknown = True
    return not have_unknown


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("-i", "--infile", help="input file name", metavar="fname")
    parser.add_argument(
        "-o",
        "--outfile",
        help="write to output file, otherwise to stdout, "
        "provide file name or will default to one based on infile",
        metavar="fname",
        nargs="?",
        const="-default-",
    )
    parser.add_argument(
        "-op",
        "--operation",
        help="read csv, or write csv",
        metavar="op",
        choices=["read", "write"],
        default="read",
    )
    parser.add_argument(
        "-s", "--scripts", help="limit to these scripts", metavar="script", nargs="*"
    )
    parser.add_argument(
        "-xs",
        "--exclude_scripts",
        help="omit these scripts",
        metavar="script",
        nargs="*",
    )

    args = parser.parse_args()

    if not _check_scripts(args.scripts):
        sys.stderr.write("some scripts failed\n")
        return
    if not _check_scripts(args.exclude_scripts):
        sys.stderr.write("some exclude scripts failed\n")
        return

    if args.outfile == "-default-":
        args.outfile = path.splitext(path.basename(args.infile))[0]
        args.outfile += ".xml" if args.operation == "read" else ".csv"
    if args.operation == "read":
        csv_to_xml(args.infile, args.outfile, args.scripts, args.exclude_scripts)
    else:
        xml_to_csv(args.infile, args.outfile, args.scripts, args.exclude_scripts)


if __name__ == "__main__":
    main()
