#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (C) 2017-2020  The Project X-Ray Authors.
#
# Use of this source code is governed by a ISC-style
# license that can be found in the LICENSE file or at
# https://opensource.org/licenses/ISC
#
# SPDX-License-Identifier: ISC

import re
import argparse
import json
import functools

NUMBER_RE = re.compile(r'\d+$')


def check_sequential(speed_model):
    # combinational path models do not contain
    # the following keywords
    timing_keywords = {
        'setup': 'setup',
        'remov': 'removal',
        'hold': 'hold',
        'recov': 'recovery',
        'removal': 'removal',
        'recovery': 'recovery'
    }
    tmp = speed_model.split('_')
    for keyword in sorted(timing_keywords):
        if keyword in tmp:
            # return found keyword and it's map in SDF
            return [keyword, timing_keywords[keyword]]

    return None


# FF's can be configured to work as FF or latch
def check_ff_latch(speed_model):

    tmp = speed_model.split('_')
    if 'ff' in tmp:
        return 'ff'
    elif 'lat' in tmp:
        return 'lat'
    else:
        return None


# some bels have duplicate names e.g bufmrce_bufmrce
# this function cleans them
def clean_bname(bname):
    tmp = bname.split('_')
    if len(tmp) > 1 and tmp[0] == tmp[1]:
        return '_'.join(tmp[1:])
    return bname


def find_aliased_pin(pin, model, pin_aliases):
    """
    Searches for aliased pins in the timing model.
    The check is done using data from pin_aliases dictionary.
    The dictionary has an entry for each aliased pin.
    Each entry has two fields:

    * names : a list of all the possible aliases
    * is_property_related: a flag saying if the alias is in fact
            pin name combined with BEL property (e.g. Q[LH] pins
            in FF - in this case the pin name is Q [original name],
            but is named Q[LH] in the timing model. The suffix
            determines polarity of the FF's set/reset input).

    If is_property_related is set the function returns the original
    pin name, aliased name is returned otherwise.

    Parameters
    ----------
        pin: str
            Pin name to look for
        model: str
            Timing model
        pin_aliases: dict
            A dict of list of aliases for given bel/site

    Returns
    -------
        bool, str

        The first bool value is set to true if pin is found
        in the timing model, false otherwise.

        The second returned value is found pin name. If pin
        is not found None is returned

    >>> find_aliased_pin("a", "a_b_some_test_string", None)
    (False, None)

    >>> find_aliased_pin("d", "din_dout_setup", {"D": {"names" : ["din"], "is_property_related" : False}})
    (True, 'din')

    >>> find_aliased_pin("d", "din_dout_setup", {"D": {"names" : ["din"], "is_property_related" : True}})
    (True, 'd')

    >>> find_aliased_pin("d", "din_dout_setup", {"D": {"names" : ["notdin"], "is_property_related" : True}})
    (False, None)
    """
    if (pin_aliases is not None) and (pin.upper() in pin_aliases):
        for alias in pin_aliases[pin.upper()]['names']:
            single_word_alias = (len(alias.split('_')) == 1)
            pin_alias = alias.lower()
            if single_word_alias:
                model_to_check = model.split('_')
            else:
                model_to_check = model
            if pin_alias in model_to_check:
                if pin_aliases[pin.upper()]['is_property_related']:
                    return True, pin.lower()
                else:
                    return True, pin_alias

    return False, None


def instance_in_model(instance, model):

    if len(instance.split('_')) == 1:
        # instance name is one word, search it in the model
        return instance in model.split('_')
    else:
        # instance name is multi word, search for a string
        return instance in model


def create_pin_in_model(pin_aliases):
    """
    Checks if a given pin belongs to the model.

    Parameters
    ----------
        pin: str
            Pin name to look for
        pin_aliases: dict
            A dict of list of aliases for given bel/site
        model: str
            Timing model name
        direction: str
            Optional pin direction suffix [IN|OUT]

    Returns
    -------
        bool, str

        The first returned value is set to true if pin is found,
        false otherwise.

        The second returned value contains found pin name. If the
        pin is not found, None is returned.

    >>> create_pin_in_model(None)("d", "ff_init_din_q", "in")
    (True, 'din')

    >>> create_pin_in_model(None)("q", "ff_init_clk_q", None)
    (True, 'q')

    >>> create_pin_in_model({"Q": {"names" : ["QL", "QH"], "is_property_related" : True}})("q", "ff_init_clk_ql", None)
    (True, 'q')

    >>> create_pin_in_model(None)("logic_out", "my_cell_i_logic_out", None)
    (True, 'logic_out')

    >>> create_pin_in_model({"LOGIC_OUT": {"names" : ["LOGIC_O", "O"], "is_property_related" : False}})("logic_out", "my_cell_i_logic_o", None)
    (True, 'logic_o')

    >>> create_pin_in_model({"LOGIC_OUT": {"names" : ["LOGIC_O", "O"], "is_property_related" : False}})("logic_out", "my_cell_i_o", None)
    (True, 'o')
    """

    @functools.lru_cache(maxsize=10000)
    def pin_in_model(pin, model, direction=None):
        # strip site location
        model = model.split(':')[0]

        extended_pin_name = pin
        aliased_pin, aliased_pin_name = find_aliased_pin(
            pin.upper(), model, pin_aliases)

        # some timings reports pins with their directions
        # this happens for e.g. CLB reg_init D pin, which
        # timing is reported as DIN
        if direction is not None:
            extended_pin_name = pin + direction

        if instance_in_model(pin, model):
            return True, pin
        elif instance_in_model(extended_pin_name, model):
            return True, extended_pin_name
        elif aliased_pin:
            return True, aliased_pin_name
        else:
            return False, None

    return pin_in_model


def remove_pin_from_model(pin, model):
    """
    Removes the pin from model name if present.

    Arguments
    ---------

    pin: str
        Pin name
    mode: str
        Timing model name

    Returns
    -------

    str
        Updated timing model name

    >>> remove_pin_from_model("q", "ff_init_d_q")
    'ff_init_d'
    >>> remove_pin_from_model("q", "ff_init_d_ql")
    'ff_init_d_ql'
    >>> remove_pin_from_model("logic_out", "ff_init_d_logic_out")
    'ff_init_d'
    >>> remove_pin_from_model("logic_out", "ff_init_d_second_out")
    'ff_init_d_second_out'
    """

    if len(pin.split('_')) == 1:
        # pin name is one word, search it in the model
        tmp = model.split('_')
        if pin in tmp:
            tmp.remove(pin)
            return "_".join(tmp)
        else:
            return model
    else:
        # pin name is multi word, search for a string
        return "_".join(list(filter(None, model.replace(pin, '').split('_'))))


def merged_dict(itr):
    """ Create a merged dict of dict (of dict) based on input.

    Input is an iteratable of (keys, value).

    Return value is root dictionary

    Keys are successive dictionaries indicies.  For example:
    (('a', 'b', 'c'), 1)

    would set:

    output['a']['b']['c'] = 1

    This function returns an error if two values conflict.

    >>> merged_dict(((('a', 'b', 'c'), 1), (('a', 'b', 'd'), 2)))
    {'a': {'b': {'c': 1, 'd': 2}}}

    """

    output = {}
    for keys, value in itr:
        target = output
        for key in keys[:-1]:
            if key not in target:
                target[key] = {}
            target = target[key]

        if keys[-1] in target:
            assert target[keys[-1]] == value, (keys, value, target[keys[-1]])
        else:
            target[keys[-1]] = value

    return output


def extract_properties(tile, site, bel, properties, model):

    if tile not in properties:
        return None
    if site not in properties[tile]:
        return None
    if bel not in properties[tile][site]:
        return None

    model_properties = dict()

    for prop in properties[tile][site][bel]:
        if prop in model_properties:
            continue
        if instance_in_model(prop.lower(), model):
            # if there is property there must be value
            # value always follow the property
            for value in properties[tile][site][bel][prop]:
                value = value.replace(',', '')
                prop_val_str = "_".join([prop, value])
                if instance_in_model(prop_val_str.lower(), model):
                    model_properties[prop] = value
                    break

    return model_properties


def parse_raw_timing(fin):
    with open(fin, "r") as f:
        for line in f:
            raw_data = line.split()
            slice = raw_data[0]

            sites_count = int(raw_data[1])
            loc = 2
            for site in range(0, sites_count):

                site_name = raw_data[loc]
                bels_count = int(raw_data[loc + 1])

                # read all BELs data within
                loc += 2
                for bel in range(0, bels_count):
                    bel = raw_data[loc]
                    delay_count = int(raw_data[loc + 1])

                    # get all the delays
                    loc += 2
                    for delay in range(0, delay_count):
                        speed_model = raw_data[loc]

                        # each timing entry reports 5 delays
                        timing = [
                            raw_data[d + 1 + loc].split(':')
                            for d in range(0, 5)
                        ]

                        yield slice, site_name, bel, speed_model, timing

                        # 5 delay values + name
                        loc += 6


def read_raw_timings(fin, properties, pins, site_pins, pin_alias_map):
    def inner():
        raw = list(parse_raw_timing(fin))

        pin_in_models = {}

        for slice, site_name, bel, speed_model, timing in raw:
            btype = bel.lower()
            delay_btype = clean_bname(btype)
            delay_btype_orig = delay_btype

            # all the bel names seem to start with "bel_d_"
            # let's get rid of it
            if speed_model.startswith('bel_d_'):
                speed_model = speed_model[6:]

            # keep original speed model string to use as unique dict entry
            speed_model_orig = speed_model

            # if more than one BEL type exists in the slice
            # location is added at the end of the name
            tmp = speed_model.split(':')
            speed_model = tmp[0]

            bel_location = site_name
            if len(tmp) > 2:
                bel_location += "/" + "/".join(tmp[2:])

            bel_location = bel_location.upper()

            sequential = check_sequential(speed_model)
            if sequential is not None:
                tmp = speed_model.split('_')
                tmp.remove(sequential[0])
                speed_model = '_'.join(tmp)

            bel_input = None
            bel_output = None
            bel_clock = None

            # strip btype from speed model so we can search for pins
            speed_model_clean = speed_model
            if speed_model.startswith(delay_btype):
                speed_model_clean = speed_model[len(delay_btype):]

            # remove properties from the model
            speed_model_properties = extract_properties(
                slice, site_name, delay_btype_orig, properties,
                speed_model_clean)
            if speed_model_properties is not None:
                for prop in speed_model_properties:
                    # properties values in the model always follow properties name
                    prop_string = "_".join(
                        [prop, speed_model_properties[prop]])
                    speed_model_clean = remove_pin_from_model(
                        prop_string.lower(), speed_model_clean)

            # Get pin alias map
            if delay_btype not in pin_in_models:
                pin_aliases = pin_alias_map.get(delay_btype, None)
                pin_in_models[delay_btype] = create_pin_in_model(pin_aliases)

            pin_in_model = pin_in_models[delay_btype]

            # locate pins
            for pin in pins[slice][site_name][delay_btype_orig]:
                orig_pin = pin
                pim, pin = pin_in_model(pin.lower(), speed_model_clean, 'in')

                if pim:
                    if pins[slice][site_name][delay_btype_orig][orig_pin][
                            'is_clock'] and not pins[slice][site_name][
                                delay_btype_orig][orig_pin]['is_part_of_bus']:
                        bel_clock = pin
                        bel_clock_orig_pin = orig_pin
                    elif pins[slice][site_name][delay_btype_orig][orig_pin][
                            'direction'] == 'IN':
                        bel_input = pin
                    elif pins[slice][site_name][delay_btype_orig][orig_pin][
                            'direction'] == 'OUT':
                        bel_output = pin
                    speed_model_clean = remove_pin_from_model(
                        pin.lower(), speed_model_clean)

            # Some speed models describe delays from/to site pins instead of BEL pins
            if bel_clock is None:
                for pin in site_pins[slice][site_name.lower()]:
                    orig_pin = pin
                    pim, pin = pin_in_model(pin.lower(), speed_model_clean)
                    if pim:
                        if site_pins[slice][site_name.lower(
                        )][orig_pin]['is_clock'] and not site_pins[slice][
                                site_name.lower()][orig_pin]['is_part_of_bus']:
                            bel_clock = pin
                            bel_clock_orig_pin = orig_pin
                            speed_model_clean = remove_pin_from_model(
                                pin.lower(), speed_model_clean)

            if bel_input is None:
                # search site inputs
                for pin in site_pins[slice][site_name.lower()]:
                    orig_pin = pin
                    pim, pin = pin_in_model(
                        pin.lower(), speed_model_clean, 'in')
                    if pim:
                        if site_pins[slice][site_name.lower(
                        )][orig_pin]['direction'] == 'IN':
                            bel_input = pin
                            speed_model_clean = remove_pin_from_model(
                                pin.lower(), speed_model_clean)

            if bel_output is None:
                for pin in site_pins[slice][site_name.lower()]:
                    orig_pin = pin
                    pim, pin = pin_in_model(pin.lower(), speed_model_clean)
                    if pim:
                        if site_pins[slice][site_name.lower(
                        )][orig_pin]['direction'] == 'OUT':
                            bel_output = pin
                            speed_model_clean = remove_pin_from_model(
                                pin.lower(), speed_model_clean)

            # if we couldn't find input, check if the clock is the
            # only input. This applies only to combinational paths
            if (sequential is None) and (bel_input is None) and (bel_clock is
                                                                 not None):
                if bel_clock_orig_pin in site_pins[slice][site_name.lower()] and \
                site_pins[slice][site_name.lower(
                )][bel_clock_orig_pin]['direction'] == 'IN':
                    bel_input = bel_clock

            # if we still don't have the input check if the input
            # is wider than 1 bit and timing defined for the whole
            # port
            if (bel_input is None) or (bel_output is None):
                for pin in pins[slice][site_name][delay_btype_orig]:
                    number = NUMBER_RE.search(pin)
                    if number is not None:
                        orig_pin = pin[:-(len(str(number.group())))]
                        orig_pin_full = pin
                        pim, pin = pin_in_model(
                            orig_pin.lower(), speed_model_clean)
                        if not pim:
                            # some inputs pins are named with unsignificant zeros
                            # remove ti and try again
                            orig_pin = orig_pin + str(int(number.group()))
                            pim, pin = pin_in_model(
                                orig_pin.lower(), speed_model_clean)

                        if pim:
                            if pins[slice][site_name][delay_btype_orig][orig_pin_full]['direction'] == 'IN' \
                                and bel_input is None:
                                bel_input = pin
                            if pins[slice][site_name][delay_btype_orig][orig_pin_full]['direction'] == 'OUT' \
                                and bel_output is None:
                                bel_output = pin
                            speed_model_clean = remove_pin_from_model(
                                orig_pin.lower(), speed_model_clean)

            # check if the input is not a BEL property
            if bel_input is None:
                # if there is anything not yet decoded
                if len(speed_model_clean.split("_")) > 1:
                    if len(speed_model_properties.keys()) == 1:
                        bel_input = list(speed_model_properties.keys())[0]

            # if we still don't have input, give up
            if bel_input is None:
                continue