#!/usr/bin/python3

# SPDX-License-Identifier: Apache-2.0
# Copyright 2020 IBM Corp.

import argparse
import csv
import enum
from collections import namedtuple
from datetime import time, timedelta

import crc8


class UCD90320Command(bytes, enum.Enum):
    def __new__(cls, value, width):
        obj = bytes.__new__(cls, [value])
        obj._value_ = value
        obj.width = width
        return obj

    MONITOR_CONFIG = (0xD5, -1)
    NUM_PAGES = (0xD6, 1)
    GPIO_SELECT = (0xFA, 1)
    GPIO_CONFIG = (0xFB, 1)
    DEVICE_ID = (0xFD, -1)


class PMBusCommand(bytes, enum.Enum):
    def __new__(cls, value, width):
        obj = bytes.__new__(cls, [value])
        obj._value_ = value
        obj.width = width
        return obj

    PAGE = (0x00, 1)
    OPERATION = (0x01, 1)
    ON_OFF_CONFIG = (0x02, 1)
    CLEAR_FAULTS = (0x03, 0)
    PHASE = (0x04, 1)
    PAGE_PLUS_WRITE = (0x05, -1)
    PAGE_PLUS_READ = (0x06, -1)
    WRITE_PROTECT = (0x10, 1)
    STORE_DEFAULT_ALL = (0x11, 0)
    RESTORE_DEFAULT_ALL = (0x12, 0)
    STORE_DEFAULT_CODE = (0x13, 1)
    RESTORE_DEFAULT_CODE = (0x14, 1)
    STORE_USER_ALL = (0x15, 0)
    RESTORE_USER_ALL = (0x16, 0)
    STORE_USER_CODE = (0x17, 1)
    RESTORE_USER_CODE = (0x18, 1)
    CAPABILITY = (0x19, 1)
    QUERY = (0x1A, 1)
    SMBALERT_MASK = (0x1B, 2)
    VOUT_MODE = (0x20, 1)
    VOUT_COMMAND = (0x21, 2)
    VOUT_CAL_OFFSET = (0x23, 2)
    POUT_MAX = (0x31, 2)
    FREQUENCY_SWITCH = (0x33, 2)
    VIN_OFF = (0x36, 2)
    FAN_COMMAND_1 = (0x3B, 2)
    FAN_COMMAND_4 = (0x3F, 2)
    VOUT_OV_FAULT_LIMIT = (0x40, 2)
    VOUT_OV_WARN_LIMIT = (0x42, 2)
    VOUT_UV_WARN_LIMIT = (0x43, 2)
    VOUT_UV_FAULT_LIMIT = (0x44, 2)
    IOUT_OC_LV_FAULT_LIMIT = (0x48, 2)
    IOUT_OC_LV_FAULT_RESPONSE = (0x49, 1)
    IOUT_UC_FAULT_RESPONSE = (0x4C, 1)
    OT_FAULT_LIMIT = (0x4F, 2)
    OT_WARN_LIMIT = (0x51, 2)
    UT_WARN_LIMIT = (0x52, 2)
    UT_FAULT_LIMIT = (0x53, 2)
    VIN_UV_FAULT_LIMIT = (0x59, 2)
    IIN_OC_FAULT_RESPONSE = (0x5C, 1)
    TOFF_MAX_WARN_LIMIT = (0x66, 2)
    STATUS_WORD = (0x79, 2)
    STATUS_CML = (0x7E, 1)
    STATUS_OTHER = (0x7F, 1)
    STATUS_MFR_SPECIFIC = (0x80, 1)
    READ_TEMPERATURE_3 = (0x8F, 2)
    PMBUS_REVISION = (0x98, 1)
    MFR_MODEL = (0x9A, -1)
    IC_DEVICE_REV = (0xAE, -1)
    USER_DATA_00 = (0xB0, -1)
    USER_DATA_08 = (0xB8, -1)
    MFR_SPECIFIC_05 = (0xD5, None)
    MFR_SPECIFIC_06 = (0xD6, None)
    MFR_SPECIFIC_42 = (0xFA, None)
    MFR_SPECIFIC_43 = (0xFB, None)
    MFR_SPECIFIC_45 = (0xFD, None)


class I2CCondition(enum.Enum):
    START = 0
    STOP = 1


class I2CRecord(enum.Enum):
    WRITE = 0
    READ = 1


class I2CResponse(enum.Enum):
    ACK = 0
    NACK = 1


# Level,Index,m:s.ms.us,Dur,Len,Err,S/P,Addr,Record,Data
# 0,1,0:29.722.525,210.600 us,1 B,,S,32,Write Transaction,0E
I2CTransfer = namedtuple(
    "I2CTransfer",
    (
        "level",
        "index",
        "timestamp",
        "duration",
        "length",
        "error",
        "conditions",
        "address",
        "record",
        "data",
    ),
)
Timestamp = namedtuple(
    "Timestamp", ["minutes", "seconds", "milliseconds", "microseconds"]
)
I2CData = namedtuple("I2CData", ["response", "data"])

SMBusTransfer = namedtuple("SMBusTransfer", ["command", "response"])


def to_duration(field):
    if field.endswith("us"):
        if "." in field:
            ms, us, _ = 0, *field.split(".")
        else:
            ms, us = 0, int(field.rstrip("us"))
    elif field.endswith("ms"):
        if "." in field:
            ms, us, _ = field.split(".")
        else:
            ms, us = int(field.rstrip("ms")), 0
    else:
        raise ValueError
    return timedelta(milliseconds=int(ms), microseconds=int(us))


def to_timestamp(field):
    ts = Timestamp(*list(int(v) for v in field.replace(":", ".").split(".")))
    return time(
        0, ts.minutes, ts.seconds, ts.milliseconds * 1000 + ts.microseconds
    )


def to_i2cdata(field):
    resp = I2CResponse.NACK if field.endswith("*") else I2CResponse.ACK
    return I2CData(resp, bytes(int(v, 16) for v in field.rstrip("*").split()))


def to_address(field):
    return int(field, 16)


def to_i2cconditions(field):
    if "S" == field:
        return {I2CCondition.START}
    elif "SP" == field:
        return {I2CCondition.START, I2CCondition.STOP}
    raise ValueError


def to_i2crecord(field):
    if "Write Transaction" == field:
        return I2CRecord.WRITE
    if "Read Transaction" == field:
        return I2CRecord.READ
    raise ValueError


def to_i2ctransfer(line):
    return I2CTransfer(
        *line[:2],
        to_timestamp(line[2]),
        to_duration(line[3]),
        *line[4:6],
        to_i2cconditions(line[6]),
        to_address(line[7]),
        to_i2crecord(line[8]),
        to_i2cdata(line[9])
    )


def pmbuscommand_style(xfer):
    return PMBusCommand(xfer.data.data[0])


def ucd90320command_style(xfer):
    try:
        return UCD90320Command(xfer.data.data[0])
    except Exception:
        return pmbuscommand_style(xfer)


def as_smbustransfers(i2cxfers, style):
    command = None
    for i2cxfer in i2cxfers:
        if i2cxfer.conditions == {I2CCondition.START}:
            assert not command
            command = i2cxfer
        if i2cxfer.conditions == {I2CCondition.START, I2CCondition.STOP}:
            if command:
                yield PMBusRead(style(command), command, i2cxfer)
                command = None
            else:
                yield PMBusWrite(style(i2cxfer), i2cxfer)


def smbus_pec(data):
    hash = crc8.crc8()
    hash.update(data)
    return hash.digest()[0]


def smbus_pec_pack_address(address, record):
    return (address << 1) | record.value


class PMBusTransfer(object):
    def calculate_pec(self):
        raise NotImplementedError

    def validate_pec(self):
        if self.pec is None:
            return True
        derived = self.calculate_pec()
        provided = self.pec
        return provided == derived

    def validate_xfer(self):
        raise NotImplementedError

    def valid(self):
        return self.validate_xfer() and self.validate_pec()


class PMBusWrite(PMBusTransfer):
    def __init__(self, command, xfer):
        assert xfer.record == I2CRecord.WRITE
        self.command = command
        self.xfer = xfer

        if command.width is None:
            start, end = 1, len(xfer.data.data)
        elif command.width == -1:
            start, end = 1, xfer.data.data[0] + 1
        else:
            start, end = 1, command.width + 1

        self.data = xfer.data.data[start:end]
        tail = self.data[end:]

        if len(tail) == 1:
            (self.pec,) = tail
        else:
            self.pec = None

        self.response = xfer.data.response

    def calculate_pec(self):
        data = (
            smbus_pec_pack_address(self.xfer.address, self.xfer.record),
            *self.xfer.data.data[:-1],
        )
        return smbus_pec(bytes(data))

    def validate_xfer(self):
        return self.response == I2CResponse.ACK

    def __str__(self):
        timestamp = self.xfer.timestamp.strftime("%M:%S.%f")
        duration = self.xfer.duration.total_seconds()
        data = "[ " + " ".join("{:02x}".format(v) for v in self.data) + " ]"

        status = []
        if self.response != I2CResponse.ACK:
            status.append(self.response.name)

        if not self.validate_pec():
            status.append("!PEC")

        if status:
            status = " ".join(status)
            fmt = (
                "{0} {1:.6f} 0x{2.xfer.address:x} {3.name} "
                + "{2.command.name} {4} {5}"
            )
            return fmt.format(
                timestamp, duration, self, I2CRecord.WRITE, data, status
            )

        fmt = "{0} {1:.6f} 0x{2.xfer.address:x} {3.name} {2.command.name} {4}"
        return fmt.format(timestamp, duration, self, I2CRecord.WRITE, data)


class PMBusRead(PMBusTransfer):
    def __init__(self, command, start, repeat):
        assert repeat.record == I2CRecord.READ
        self.command = command
        self.start = start
        self.repeat = repeat
        assert start.address == repeat.address
        self.address = start.address

        if self.command.width is None:
            start, end = 0, len(repeat.data.data)
        elif self.command.width == -1:
            start, end = 1, repeat.data.data[0] + 1
        else:
            start, end = 0, command.width

        self.data = repeat.data.data[start:end]
        tail = repeat.data.data[end:]

        if len(tail) == 1:
            (self.pec,) = tail
        else:
            self.pec = None

        self.response = repeat.data.response

    def calculate_pec(self):
        data = (
            smbus_pec_pack_address(self.start.address, self.start.record),
            *self.start.data.data,
            smbus_pec_pack_address(self.repeat.address, self.repeat.record),
            *self.repeat.data.data[:-1],
        )
        return smbus_pec(bytes(data))

    def validate_xfer(self):
        return (
            self.start.data.response == I2CResponse.ACK
            and self.repeat.data.response == I2CResponse.NACK
        )

    def __str__(self):
        timestamp = self.start.timestamp.strftime("%M:%S.%f")
        duration = self.start.duration.total_seconds()

        status = []
        if self.start.data.response != I2CResponse.ACK:
            status.append(self.start.data.response.name)

        if status:
            status = " ".join(status)
            fmt = "{0} {1:.6f} 0x{2.address:x} {3.name} {2.command.name} {4}"
            start = fmt.format(
                timestamp, duration, self, I2CRecord.READ, status
            )
        else:
            fmt = "{0} {1:.6f} 0x{2.address:x} {3.name} {2.command.name}"
            start = fmt.format(timestamp, duration, self, I2CRecord.READ)

        timestamp = self.repeat.timestamp.strftime("%M:%S.%f")
        duration = self.repeat.duration.total_seconds()
        data = " ".join("{:02x}".format(v) for v in self.data)
        data = "[ " + data + " ]"

        status = []
        if self.repeat.data.response != I2CResponse.NACK:
            status.append(self.repeat.data.response.name)

        if not self.validate_pec():
            status.append("!PEC")

        status = " ".join(status)
        fmt = "{0} {1:.6f} {2} {3}"
        repeat = fmt.format(timestamp, duration, data, status)

        return start + " | " + repeat


def filter_source(src):
    for line in src:
        if not line:
            continue
        if line.startswith("#"):
            continue
        if "Capture started" in line:
            continue
        if "Capture stopped" in line:
            continue
        yield line


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("--after", type=str)
    parser.add_argument("--before", type=str)
    parser.add_argument("--longer-than", type=str)
    parser.add_argument("--address", type=lambda x: int(x, 0))
    parser.add_argument("--pmbus", action="store_true")
    parser.add_argument("--ucd90320", action="store_true")
    parser.add_argument("--bad-transfers", action="store_true")
    parser.add_argument("file", type=str)
    args = parser.parse_args()
    with open(args.file, "r") as src:
        data = (line for line in filter_source(src.readlines()))
        xfers = (to_i2ctransfer(e) for e in csv.reader(data))
        if args.after:
            after = to_timestamp(args.after)
            xfers = (e for e in xfers if e.timestamp > after)
        if args.before:
            before = to_timestamp(args.before)
            xfers = (e for e in xfers if e.timestamp < before)
        if args.longer_than:
            minimum = to_duration(args.longer_than)
            xfers = (e for e in xfers if e.duration > minimum)
        if args.address is not None:
            xfers = (e for e in xfers if e.address == args.address)
        if args.ucd90320 or args.pmbus:
            if args.ucd90320:
                style = ucd90320command_style
            else:
                style = pmbuscommand_style
            for xfer in as_smbustransfers(xfers, style):
                if args.bad_transfers and xfer.valid():
                    continue
                print(xfer)
        else:
            for xfer in xfers:
                timestamp = xfer.timestamp.strftime("%M:%S.%f")
                duration = xfer.duration.total_seconds()
                data = (
                    "[ "
                    + " ".join("{:02x}".format(v) for v in xfer.data.data)
                    + " ]"
                )
                res = xfer.data.response.name
                fmt = "{0} {1:.6f} 0x{2.address:x} {2.record.name} {3} {4}"
                print(fmt.format(timestamp, duration, xfer, data, res))


if __name__ == "__main__":
    main()