#!/usr/bin/env python

"""
Generates pin source files based on an MCU alternate-function definition (eg
stm32f405_af.csv) and a board-specific pin definition file, pins.csv.

The pins.csv file can contain empty lines, comments (a line beginning with "#")
or pin definition lines.  Pin definition lines must be of the form:

    board,cpu

Where "board" is the user-facing name of the pin as specified by the particular
board layout and markings, and "cpu" is the corresponding name of the CPU/MCU
pin.

The "board" entry may be absent if the CPU pin has no additional name, and both
entries may start with "-" to hide them from the corresponding Python dict of
pins, and hence hide them from the user (but they are still accessible in C).

For example, take the following pins.csv file:

    X1,PA0
    -X2,PA1
    X3,-PA2
    -X4,-PA3
    ,PA4
    ,-PA5

The first row here configures:
- The CPU pin PA0 is labelled X1.
- The Python user can access both by the names Pin("X1") and Pin("A0").
- The Python user can access both by the members Pin.board.X1 and Pin.cpu.A0.
- In C code they are available as pyb_pin_X1 and pin_A0.

Prefixing the names with "-" hides them from the user.  The following table
summarises the various possibilities:

    pins.csv entry | board name | cpu name | C board name | C cpu name
    ---------------+------------+----------+--------------+-----------
    X1,PA0           "X1"         "A0"       pyb_pin_X1     pin_A0
    -X2,PA1          -            "A1"       pyb_pin_X2     pin_A1
    X3,-PA2          "X3"         -          pyb_pin_X3     pin_A2
    -X4,-PA3         -            -          pyb_pin_X4     pin_A3
    ,PA4             -            "A4"       -              pin_A4
    ,-PA5            -            -          -              pin_A5

"""

from __future__ import print_function

import argparse
import sys
import csv

# Must have matching entries in AF_FN_* enum in ../pin_defs_stm32.h
SUPPORTED_FN = {
    "TIM": ["CH1", "CH2", "CH3", "CH4", "CH1N", "CH2N", "CH3N", "CH1_ETR", "ETR", "BKIN"],
    "I2C": ["SDA", "SCL"],
    "I2S": ["CK", "MCK", "SD", "WS", "EXTSD"],
    "USART": ["RX", "TX", "CTS", "RTS", "CK"],
    "UART": ["RX", "TX", "CTS", "RTS"],
    "LPUART": ["RX", "TX", "CTS", "RTS"],
    "SPI": ["NSS", "SCK", "MISO", "MOSI"],
    "SDMMC": ["CK", "CMD", "D0", "D1", "D2", "D3"],
    "CAN": ["TX", "RX"],
}

CONDITIONAL_VAR = {
    "I2C": "MICROPY_HW_I2C{num}_SCL",
    "I2S": "MICROPY_HW_I2S{num}",
    "SPI": "MICROPY_HW_SPI{num}_SCK",
    "UART": "MICROPY_HW_UART{num}_TX",
    "LPUART": "MICROPY_HW_LPUART{num}_TX",
    "USART": "MICROPY_HW_UART{num}_TX",
    "SDMMC": "MICROPY_HW_SDMMC{num}_CK",
    "CAN": "MICROPY_HW_CAN{num}_TX",
}


def parse_port_pin(name_str):
    """Parses a string and returns a (port-num, pin-num) tuple."""
    if len(name_str) < 3:
        raise ValueError("Expecting pin name to be at least 3 charcters.")
    if name_str[0] != "P":
        raise ValueError("Expecting pin name to start with P")
    if name_str[1] < "A" or name_str[1] > "K":
        raise ValueError("Expecting pin port to be between A and K")
    port = ord(name_str[1]) - ord("A")
    pin_str = name_str[2:]
    if not pin_str.isdigit():
        raise ValueError("Expecting numeric pin number.")
    return (port, int(pin_str))


def split_name_num(name_num):
    num = None
    for num_idx in range(len(name_num) - 1, -1, -1):
        if not name_num[num_idx].isdigit():
            name = name_num[0 : num_idx + 1]
            num_str = name_num[num_idx + 1 :]
            if len(num_str) > 0:
                num = int(num_str)
            break
    return name, num


def conditional_var(name_num):
    # Try the specific instance first. For example, if name_num is UART4_RX
    # then try UART4 first, and then try UART second.
    name, num = split_name_num(name_num)
    var = []
    if name in CONDITIONAL_VAR:
        var.append(CONDITIONAL_VAR[name].format(num=num))
    if name_num in CONDITIONAL_VAR:
        var.append(CONDITIONAL_VAR[name_num])
    return var


def print_conditional_if(cond_var, file=None):
    if cond_var:
        cond_str = []
        for var in cond_var:
            if var.find("ENABLE") >= 0:
                cond_str.append("(defined({0}) && {0})".format(var))
            else:
                cond_str.append("defined({0})".format(var))
        print("#if " + " || ".join(cond_str), file=file)


def print_conditional_endif(cond_var, file=None):
    if cond_var:
        print("#endif", file=file)


class AlternateFunction(object):
    """Holds the information associated with a pins alternate function."""

    def __init__(self, idx, af_str):
        self.idx = idx
        # Special case. We change I2S2ext_SD into I2S2_EXTSD so that it parses
        # the same way the other peripherals do.
        af_str = af_str.replace("ext_", "_EXT")

        self.af_str = af_str

        self.func = ""
        self.fn_num = None
        self.pin_type = ""
        self.supported = False

        af_words = af_str.split("_", 1)
        self.func, self.fn_num = split_name_num(af_words[0])
        if len(af_words) > 1:
            self.pin_type = af_words[1]
        if self.func in SUPPORTED_FN:
            pin_types = SUPPORTED_FN[self.func]
            if self.pin_type in pin_types:
                self.supported = True

    def is_supported(self):
        return self.supported

    def ptr(self):
        """Returns the numbered function (i.e. USART6) for this AF."""
        if self.fn_num is None:
            return self.func
        return "{:s}{:d}".format(self.func, self.fn_num)

    def mux_name(self):
        return "AF{:d}_{:s}".format(self.idx, self.ptr())

    def print(self):
        """Prints the C representation of this AF."""
        cond_var = None
        if self.supported:
            cond_var = conditional_var("{}{}".format(self.func, self.fn_num))
            print_conditional_if(cond_var)
            print("  AF", end="")
        else:
            print("  //", end="")
        fn_num = self.fn_num
        if fn_num is None:
            fn_num = 0
        print(
            "({:2d}, {:8s}, {:2d}, {:10s}, {:8s}), // {:s}".format(
                self.idx, self.func, fn_num, self.pin_type, self.ptr(), self.af_str
            )
        )
        print_conditional_endif(cond_var)

    def qstr_list(self):
        return [self.mux_name()]


class Pin(object):
    """Holds the information associated with a pin."""

    def __init__(self, port, pin):
        self.port = port
        self.pin = pin
        self.alt_fn = []
        self.alt_fn_count = 0
        self.adc_num = 0
        self.adc_channel = 0
        self.board_pin = False

    def port_letter(self):
        return chr(self.port + ord("A"))

    def cpu_pin_name(self):
        return "{:s}{:d}".format(self.port_letter(), self.pin)

    def is_board_pin(self):
        return self.board_pin

    def set_is_board_pin(self):
        self.board_pin = True

    def parse_adc(self, adc_str):
        if adc_str[:3] != "ADC":
            return
        adc, channel = None, None

        if adc_str.find("_INP") != -1:
            # STM32H7xx, entries have the form: ADCxx_IN[PN]yy/...
            sep = "_INP"
        else:
            # all other MCUs, entries have the form: ADCxx_INyy
            sep = "_IN"

        # Pick the entry with the most ADC peripherals
        for ss in adc_str.split("/"):
            if ss.find(sep) != -1:
                a, c = ss.split("_")
                if adc is None or len(a) > len(adc):
                    adc, channel = a, c
        if adc is None:
            return
        channel = channel[len(sep) - 1 :]

        for idx in range(3, len(adc)):
            adc_num = int(adc[idx])  # 1, 2, or 3
            self.adc_num |= 1 << (adc_num - 1)
        self.adc_channel = int(channel)

    def parse_af(self, af_idx, af_strs_in):
        if len(af_strs_in) == 0:
            return
        # If there is a slash, then the slash separates 2 aliases for the
        # same alternate function.
        af_strs = af_strs_in.split("/")
        for af_str in af_strs:
            alt_fn = AlternateFunction(af_idx, af_str)
            self.alt_fn.append(alt_fn)
            if alt_fn.is_supported():
                self.alt_fn_count += 1

    def alt_fn_name(self, null_if_0=False):
        if null_if_0 and self.alt_fn_count == 0:
            return "NULL"
        return "pin_{:s}_af".format(self.cpu_pin_name())

    def adc_num_str(self):
        str = ""
        for adc_num in range(1, 4):
            if self.adc_num & (1 << (adc_num - 1)):
                if len(str) > 0:
                    str += " | "
                str += "PIN_ADC"
                str += chr(ord("0") + adc_num)
        if len(str) == 0:
            str = "0"
        return str

    def print(self):
        if self.alt_fn_count == 0:
            print("// ", end="")
        print("const pin_af_obj_t {:s}[] = {{".format(self.alt_fn_name()))
        for alt_fn in self.alt_fn:
            alt_fn.print()
        if self.alt_fn_count == 0:
            print("// ", end="")
        print("};")
        print("")
        print(
            "const pin_obj_t pin_{:s}_obj = PIN({:s}, {:d}, {:s}, {:s}, {:d});".format(
                self.cpu_pin_name(),
                self.port_letter(),
                self.pin,
                self.alt_fn_name(null_if_0=True),
                self.adc_num_str(),
                self.adc_channel,
            )
        )
        print("")

    def print_header(self, hdr_file):
        n = self.cpu_pin_name()
        hdr_file.write("extern const pin_obj_t pin_{:s}_obj;\n".format(n))
        hdr_file.write("#define pin_{:s} (&pin_{:s}_obj)\n".format(n, n))
        if self.alt_fn_count > 0:
            hdr_file.write("extern const pin_af_obj_t pin_{:s}_af[];\n".format(n))

    def qstr_list(self):
        result = []
        for alt_fn in self.alt_fn:
            if alt_fn.is_supported():
                result += alt_fn.qstr_list()
        return result


class NamedPin(object):
    def __init__(self, name, pin):
        if name.startswith("-"):
            self._is_hidden = True
            self._name = name[1:]
        else:
            self._is_hidden = False
            self._name = name
        self._pin = pin

    def set_hidden(self, value):
        self._is_hidden = value

    def is_hidden(self):
        return self._is_hidden

    def pin(self):
        return self._pin

    def name(self):
        return self._name


class Pins(object):
    def __init__(self):
        self.cpu_pins = []  # list of NamedPin objects
        self.board_pins = []  # list of NamedPin objects
        self.adc_table_size = {}  # maps ADC number X to size of pin_adcX table

    def find_pin(self, port_num, pin_num):
        for named_pin in self.cpu_pins:
            pin = named_pin.pin()
            if pin.port == port_num and pin.pin == pin_num:
                return named_pin

    def parse_af_file(self, filename, pinname_col, af_col):
        with open(filename, "r") as csvfile:
            rows = csv.reader(csvfile)
            for row in rows:
                try:
                    (port_num, pin_num) = parse_port_pin(row[pinname_col])
                except:
                    continue
                pin = Pin(port_num, pin_num)
                for af_idx in range(af_col, len(row)):
                    if af_idx < af_col + 16:
                        pin.parse_af(af_idx - af_col, row[af_idx])
                    elif af_idx == af_col + 16:
                        pin.parse_adc(row[af_idx])
                self.cpu_pins.append(NamedPin(pin.cpu_pin_name(), pin))

    def parse_board_file(self, filename):
        with open(filename, "r") as csvfile:
            rows = csv.reader(csvfile)
            for row in rows:
                if len(row) == 0 or row[0].startswith("#"):
                    # Skip empty lines, and lines starting with "#"
                    continue
                if len(row) != 2:
                    raise ValueError("Expecting two entries in a row")

                cpu_pin_name = row[1]
                cpu_pin_hidden = False
                if cpu_pin_name.startswith("-"):
                    cpu_pin_name = cpu_pin_name[1:]
                    cpu_pin_hidden = True
                try:
                    (port_num, pin_num) = parse_port_pin(cpu_pin_name)
                except:
                    continue
                named_pin = self.find_pin(port_num, pin_num)
                if named_pin:
                    named_pin.set_hidden(cpu_pin_hidden)
                    pin = named_pin.pin()
                    pin.set_is_board_pin()
                    if row[0]:  # Only add board pins that have a name
                        self.board_pins.append(NamedPin(row[0], pin))

    def print_named(self, label, named_pins):
        print(
            "STATIC const mp_rom_map_elem_t pin_{:s}_pins_locals_dict_table[] = {{".format(label)
        )
        for named_pin in named_pins:
            pin = named_pin.pin()
            if pin.is_board_pin() and not named_pin.is_hidden():
                print(
                    "  {{ MP_ROM_QSTR(MP_QSTR_{:s}), MP_ROM_PTR(&pin_{:s}_obj) }},".format(
                        named_pin.name(), pin.cpu_pin_name()
                    )
                )
        print("};")
        print(
            "MP_DEFINE_CONST_DICT(pin_{:s}_pins_locals_dict, pin_{:s}_pins_locals_dict_table);".format(
                label, label
            )
        )

    def print(self):
        for named_pin in self.cpu_pins:
            pin = named_pin.pin()
            if pin.is_board_pin():
                pin.print()
        self.print_named("cpu", self.cpu_pins)
        print("")
        self.print_named("board", self.board_pins)

    def print_adc(self, adc_num):
        adc_pins = {}
        for named_pin in self.cpu_pins:
            pin = named_pin.pin()
            if (
                pin.is_board_pin()
                and not named_pin.is_hidden()
                and (pin.adc_num & (1 << (adc_num - 1)))
            ):
                adc_pins[pin.adc_channel] = pin
        if adc_pins:
            table_size = max(adc_pins) + 1
        else:
            # If ADCx pins are hidden, print an empty table to prevent linker errors.
            table_size = 0
        self.adc_table_size[adc_num] = table_size
        print("")
        print("const pin_obj_t * const pin_adc{:d}[{:d}] = {{".format(adc_num, table_size))
        for channel in range(table_size):
            if channel in adc_pins:
                obj = "&pin_{:s}_obj".format(adc_pins[channel].cpu_pin_name())
            else:
                obj = "NULL"
            print("  [{:d}] = {},".format(channel, obj))
        print("};")

    def print_header(self, hdr_filename, obj_decls):
        with open(hdr_filename, "wt") as hdr_file:
            if obj_decls:
                for named_pin in self.cpu_pins:
                    pin = named_pin.pin()
                    if pin.is_board_pin():
                        pin.print_header(hdr_file)
                for adc_num, table_size in self.adc_table_size.items():
                    hdr_file.write(
                        "extern const pin_obj_t * const pin_adc{:d}[{:d}];\n".format(
                            adc_num, table_size
                        )
                    )
            # provide #define's mapping board to cpu name
            for named_pin in self.board_pins:
                hdr_file.write(
                    "#define pyb_pin_{:s} pin_{:s}\n".format(
                        named_pin.name(), named_pin.pin().cpu_pin_name()
                    )
                )

    def print_qstr(self, qstr_filename):
        with open(qstr_filename, "wt") as qstr_file:
            qstr_set = set([])
            for named_pin in self.cpu_pins:
                pin = named_pin.pin()
                if pin.is_board_pin():
                    qstr_set |= set(pin.qstr_list())
                    qstr_set |= set([named_pin.name()])
            for named_pin in self.board_pins:
                if not named_pin.is_hidden():
                    qstr_set |= set([named_pin.name()])
            for qstr in sorted(qstr_set):
                cond_var = None
                if qstr.startswith("AF"):
                    af_words = qstr.split("_")
                    cond_var = conditional_var(af_words[1])
                    print_conditional_if(cond_var, file=qstr_file)
                print("Q({})".format(qstr), file=qstr_file)
                print_conditional_endif(cond_var, file=qstr_file)

    def print_af_hdr(self, af_const_filename):
        with open(af_const_filename, "wt") as af_const_file:
            af_hdr_set = set([])
            mux_name_width = 0
            for named_pin in self.cpu_pins:
                pin = named_pin.pin()
                if pin.is_board_pin():
                    for af in pin.alt_fn:
                        if af.is_supported():
                            mux_name = af.mux_name()
                            af_hdr_set |= set([mux_name])
                            if len(mux_name) > mux_name_width:
                                mux_name_width = len(mux_name)
            for mux_name in sorted(af_hdr_set):
                af_words = mux_name.split("_")  # ex mux_name: AF9_I2C2
                cond_var = conditional_var(af_words[1])
                print_conditional_if(cond_var, file=af_const_file)
                key = "MP_ROM_QSTR(MP_QSTR_{}),".format(mux_name)
                val = "MP_ROM_INT(GPIO_{})".format(mux_name)
                print("    { %-*s %s }," % (mux_name_width + 26, key, val), file=af_const_file)
                print_conditional_endif(cond_var, file=af_const_file)

    def print_af_defs(self, af_defs_filename, cmp_strings):
        with open(af_defs_filename, "wt") as af_defs_file:

            STATIC_AF_TOKENS = {}
            for named_pin in self.cpu_pins:
                for af in named_pin.pin().alt_fn:
                    func = "%s%d" % (af.func, af.fn_num) if af.fn_num else af.func
                    pin_type = (af.pin_type or "NULL").split("(")[0]
                    tok = "#define STATIC_AF_%s_%s(pin_obj) ( \\" % (func, pin_type)
                    if tok not in STATIC_AF_TOKENS:
                        STATIC_AF_TOKENS[tok] = []
                    if cmp_strings:
                        pin_name = named_pin.pin().cpu_pin_name()
                        cmp_str = (
                            '    ((strcmp( #pin_obj , "(&pin_%s_obj)") '
                            ' & strcmp( #pin_obj , "((&pin_%s_obj))")) == 0) ? (%d) : \\'
                            % (pin_name, pin_name, af.idx)
                        )
                    else:
                        cmp_str = "    ((pin_obj) == (pin_%s)) ? (%d) : \\" % (
                            named_pin.pin().cpu_pin_name(),
                            af.idx,
                        )
                    STATIC_AF_TOKENS[tok].append(cmp_str)

            for tok, pins in STATIC_AF_TOKENS.items():
                print(tok, file=af_defs_file)
                print("\n".join(sorted(pins)), file=af_defs_file)
                print("    (0xffffffffffffffffULL))\n", file=af_defs_file)

    def print_af_py(self, af_py_filename):
        with open(af_py_filename, "wt") as af_py_file:
            print("PINS_AF = (", file=af_py_file)
            for named_pin in self.board_pins:
                if named_pin.is_hidden():
                    continue
                print("  ('%s', " % named_pin.name(), end="", file=af_py_file)
                for af in named_pin.pin().alt_fn:
                    if af.is_supported():
                        print("(%d, '%s'), " % (af.idx, af.af_str), end="", file=af_py_file)
                print("),", file=af_py_file)
            print(")", file=af_py_file)


def main():
    parser = argparse.ArgumentParser(
        prog="make-pins.py",
        usage="%(prog)s [options] [command]",
        description="Generate board specific pin file",
    )
    parser.add_argument(
        "-a",
        "--af",
        dest="af_filename",
        help="Specifies the alternate function file for the chip",
        default="stm32f4xx_af.csv",
    )
    parser.add_argument(
        "--af-const",
        dest="af_const_filename",
        help="Specifies header file for alternate function constants.",
        default="build/pins_af_const.h",
    )
    parser.add_argument(
        "--af-py",
        dest="af_py_filename",
        help="Specifies the filename for the python alternate function mappings.",
        default="build/pins_af.py",
    )
    parser.add_argument(
        "--af-defs",
        dest="af_defs_filename",
        help="Specifies the filename for the alternate function defines.",
        default="build/pins_af_defs.h",
    )
    parser.add_argument(
        "--af-defs-cmp-strings",
        dest="af_defs_cmp_strings",
        help="Whether to compare pin name strings for the alternate function defines instead of object values",
        action="store_true",
    )
    parser.add_argument(
        "-b",
        "--board",
        dest="board_filename",
        help="Specifies the board file",
    )
    parser.add_argument(
        "-p",
        "--prefix",
        dest="prefix_filename",
        help="Specifies beginning portion of generated pins file",
        default="stm32f4xx_prefix.c",
    )
    parser.add_argument(
        "-q",
        "--qstr",
        dest="qstr_filename",
        help="Specifies name of generated qstr header file",
        default="build/pins_qstr.h",
    )
    parser.add_argument(
        "-r",
        "--hdr",
        dest="hdr_filename",
        help="Specifies name of generated pin header file",
        default="build/pins.h",
    )
    parser.add_argument(
        "--hdr-obj-decls",
        dest="hdr_obj_decls",
        help="Whether to include declarations for pin objects in pin header file",
        action="store_true",
    )
    args = parser.parse_args(sys.argv[1:])

    pins = Pins()

    print("// This file was automatically generated by make-pins.py")
    print("//")
    if args.af_filename:
        print("// --af {:s}".format(args.af_filename))
        pins.parse_af_file(args.af_filename, 1, 2)

    if args.board_filename:
        print("// --board {:s}".format(args.board_filename))
        pins.parse_board_file(args.board_filename)

    if args.prefix_filename:
        print("// --prefix {:s}".format(args.prefix_filename))
        print("")
        with open(args.prefix_filename, "r") as prefix_file:
            print(prefix_file.read())
    pins.print()
    for i in range(1, 4):
        pins.print_adc(i)
    pins.print_header(args.hdr_filename, args.hdr_obj_decls)
    pins.print_qstr(args.qstr_filename)
    pins.print_af_hdr(args.af_const_filename)
    pins.print_af_py(args.af_py_filename)
    pins.print_af_defs(args.af_defs_filename, args.af_defs_cmp_strings)


if __name__ == "__main__":
    main()
