#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright 2020 The SkyWater PDK Authors.
#
# Use of this source code is governed by the Apache 2.0
# license that can be found in the LICENSE file or at
# https://www.apache.org/licenses/LICENSE-2.0
#
# SPDX-License-Identifier: Apache-2.0

import hashlib
import json
import os
import pprint
import re
import sys
import traceback

from skywater_pdk import base, corners, drives

import hdlparse.verilog_parser as vlog

copyright_header = """\
// Copyright 2020 The Skywater PDK Authors
//
// 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
//
//     https://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.
//
// SPDX-License-Identifier: Apache-2.0
"""

vlog_ex = vlog.VerilogExtractor()

IMPORTANT = [
    'cell.json',
    'full.v',
    'specify.v',
    'gds',
    'cdl',
    'sp',
]

IGNORE = [
    re.compile('README.rst$'),
    re.compile('.Cat$'),
    re.compile('metadata.json$'),
    re.compile('wrap.json'),
    re.compile('wrap.lib'),
    re.compile('define_functional'),
]
ALLOW_ERRORS = [
    re.compile('/pg_u_'),
    re.compile('/udb_pg_u_'),
    re.compile('/udb_u_'),
    re.compile('/u_'),
    re.compile('_pg$'),
    re.compile('fill'),
    re.compile('tap'),
    re.compile('decap'),
    re.compile('diode'),
    re.compile('probe'),
    re.compile('libcell'),
    re.compile('lpflow_'),
    re.compile('macro_sparecell'),
    re.compile('macro_sync'),
]

def should_ignore(f, x=IGNORE):
    """
    >>> should_ignore('README.rst')
    True
    >>> should_ignore('metadata.json')
    True
    >>> should_ignore('asdfasdfasdf/README.rst')
    True
    >>> should_ignore('/home/tim/gob/foss-eda-tools/skywater-pdk-scratch/skywater-pdk/libraries/sky130_fd_sc_hd/v0.0.1/cells/README.rst')
    True
    >>> should_ignore('/home/tim/gob/foss-eda-tools/skywater-pdk-scratch/skywater-pdk/libraries/sky130_fd_sc_hd/v0.0.1/cells/XXXX')
    False

    """
    for i in x:
        if i.search(f):
            return True
    return False


def get_description(cellpath):
    readme_fn = os.path.join(cellpath, 'README.rst')
    if not os.path.exists(readme_fn):
        return ''
    readme = open(readme_fn).read()

    desc = """\
Description
***********
"""
    logic = """\
Logic
*****
"""
    assert desc in readme, readme
    assert logic in readme, readme

    _, readme = readme.split(desc, 1)
    readme, _ = readme.split(logic, 1)
    return readme.strip()


def process(cellpath):
    assert os.path.exists(cellpath), cellpath
    assert os.path.isdir(cellpath), cellpath

    files = [
        (f, os.path.abspath(os.path.join(cellpath, f)))
        for f in os.listdir(cellpath)]
    files.sort()

    dcell, fname = base.parse_pathname(cellpath)
    assert isinstance(dcell, base.Cell), (cellpath, dcell, fname)
    assert fname is None, (cellpath, dcell, fname)

    extensions = set()
    dcorners = set()
    ddrives = set()
    checksums = {}
    errors = []
    for fname, fpath in files:
        if should_ignore(fpath):
            continue

        try:
            fcell, fextra, fext = base.parse_filename(fpath)
        except Exception as e:
            traceback.print_exc()
            errors.append(e)
        assert isinstance(fcell, base.Cell), (fpath, fcell, fextra, ext)

        if fext in IMPORTANT:
            checksums[fname] = hashlib.sha1(open(fpath, 'rb').read()).hexdigest()

        extensions.add(fext)

        assert fcell.library == dcell.library, (fcell, dcell)
        if not fextra:
            continue

        if fextra.startswith('extracted') or 'spectre' in fextra:
            continue

        try:
            fcorner = corners.parse_filename(fextra)
            dcorners.add(fcorner)
        except Exception as e:
            traceback.print_exc()
            errors.append('Invalid corner: {} -- {} (from {})'.format(e, fextra, fpath))

        assert fcell.name.startswith(dcell.name), (fcell, dcell)
        if dcell.name != fcell.name:
            try:
                fdrive = fcell.name[len(dcell.name):]

                ddrives.add(drives.parse_drive(fdrive))
            except Exception as e:
                traceback.print_exc()
                errors.append('Invalid drive: {} -- {} (from {})'.format(e, fdrive, fpath))

    basepath = cellpath.split("libraries", 1)[0]
    cellrelpath = os.path.relpath(cellpath, basepath)

    metadata = dcell.to_dict()
    metadata['fullname'] = dcell.fullname
    metadata['description'] = get_description(cellpath)

    if 'full.v' in extensions:
        o = None
        for ext in ['full.v', 'simple.v']:
            fname = os.path.join(cellpath, "{}.{}".format(dcell.fullname, ext))
            if not os.path.exists(fname):
                errors.append("Missing {} file".format(fname))
                continue
            o = vlog_ex.extract_objects(fname)
            if not o or len(o) != 1:
                errors.append("Invalid {} file ({})".format(fname, o))
                continue
            o = o[0]
            if not o:
                errors.append("Invalid {} file ({})".format(fname, o))
            break
        if o:
            assert dcell.fullname in o.name, (dcell.fullname, o)
            assert not o.generics, (dcell.fullname, o)
            non_pwr = []
            pwr = []

            current_list = non_pwr
            p = list(o.ports)
            while len(p) > 0:
                a = p.pop(0)
                if a.name == 'ifdef':
                    assert len(p) > 2, p
                    pg_pin = p.pop(0)
                    assert 'SC_USE_PG_PIN' == pg_pin.name, pg_pin
                    current_list = pwr
                    continue
                elif a.name == 'endif':
                    assert len(p) == 0, p
                    break
                else:
                    current_list.append((a.name, a.mode))
            metadata['ports'] = {
                'signal': non_pwr,
                'power': pwr,
            }

    extensions.add('metadata.json')

    if not checksums:
        errors.append('No important files for {}: {}'.format(cellpath, files))
    else:
        metadata['files'] = checksums
    if dcorners:
        metadata['corners'] = [d.to_dict() for d in sorted(dcorners)]
    else:
        errors.append('Missing corners for: {}\n'.format(cellpath))

    assert extensions
    metadata['extensions'] = list(sorted(extensions))

    if ddrives:
        metadata['drives'] = [d.to_dict() for d in sorted(ddrives)]

    # Save the metadata file.
    mdata_file = os.path.join(cellpath, 'metadata.json')
    with open(mdata_file, 'w') as f:
        json.dump(metadata, f, sort_keys=True, indent="   ")
    print("Wrote:", mdata_file)

    if errors:
        raise ValueError("\n".join(str(e) for e in errors))


def main(args):
    for a in args:
        p = os.path.abspath(a)
        if should_ignore(p):
            continue
        try:
            process(p)
        except Exception as e:
            if not should_ignore(p, ALLOW_ERRORS):
                raise
            print("Failed to process ignorable:", p)
            traceback.print_exc()


if __name__ == "__main__":
    import doctest
    doctest.testmod()
    sys.exit(main(sys.argv[1:]))