# Copyright lowRISC contributors.
# Licensed under the Apache License, Version 2.0, see LICENSE for details.
# SPDX-License-Identifier: Apache-2.0
"""
Register JSON validation
"""

import logging as log
from typing import Dict, List, Tuple, Union


# validating version of int(x, 0)
# returns int value, error flag
# if error flag is True value will be zero
def check_int(x: Union[int, str],
              err_prefix: str,
              suppress_err_msg: bool = False) -> Tuple[int, bool]:
    if isinstance(x, int):
        return x, False
    if x[0] == '0' and len(x) > 2:
        if x[1] in 'bB':
            validch = '01'
        elif x[1] in 'oO':
            validch = '01234567'
        elif x[1] in 'xX':
            validch = '0123456789abcdefABCDEF'
        else:
            if not suppress_err_msg:
                log.error(err_prefix +
                          ": int must start digit, 0b, 0B, 0o, 0O, 0x or 0X")
            return 0, True
        for c in x[2:]:
            if c not in validch:
                if not suppress_err_msg:
                    log.error(err_prefix + ": Bad character " + c + " in " + x)
                return 0, True
    else:
        if not x.isdecimal():
            if not suppress_err_msg:
                log.error(err_prefix + ": Number not valid int " + x)
            return 0, True
    return int(x, 0), False


def check_bool(x: Union[bool, str], err_prefix: str) -> Tuple[bool, bool]:
    """check_bool checks if input 'x' is one of the list:
        "true", "false"

        It returns value as Bool type and Error condition.
    """
    if isinstance(x, bool):
        # if Bool returns as it is
        return x, False
    if not x.lower() in ["true", "false"]:
        log.error(err_prefix + ": Bad field value " + x)
        return False, True
    else:
        return (x.lower() == "true"), False


def check_ln(obj: Dict[str, object],
             x: str,
             withwidth: bool,
             err_prefix: str) -> int:
    error = 0
    entry = obj[x]
    if not isinstance(entry, list):
        log.error(err_prefix + ' element ' + x + ' not a list')
        return 1

    for y in entry:
        error += check_keys(y, ln_required, ln_optional if withwidth else {},
                            {}, err_prefix + ' element ' + x)
        if withwidth:
            if 'width' in y:
                w, err = check_int(y['width'], err_prefix + ' width in ' + x)
                if err:
                    error += 1
                    w = 1
            else:
                w = 1
            y['width'] = str(w)

    return error


def check_keys(obj: Dict[str, object],
               required_keys: Dict[str, List[str]],
               optional_keys: Dict[str, List[str]],
               added_keys: Dict[str, List[str]],
               err_prefix: str) -> int:
    error = 0
    for x in required_keys:
        if x not in obj:
            error += 1
            log.error(err_prefix + " missing required key " + x)
    for x in obj:
        type = None
        if x in required_keys:
            type = required_keys[x][0]
        elif x in optional_keys:
            type = optional_keys[x][0]
        elif x not in added_keys:
            log.warning(err_prefix + " contains extra key " + x)
        if type is not None:
            if type[:2] == 'ln':
                error += check_ln(obj, x, type == 'lnw', err_prefix)

    return error


val_types = {
    'd': ["int", "integer (binary 0b, octal 0o, decimal, hex 0x)"],
    'x': ["xint", "x for undefined otherwise int"],
    'b': [
        "bitrange", "bit number as decimal integer, "
        "or bit-range as decimal integers msb:lsb"
    ],
    'l': ["list", "comma separated list enclosed in `[]`"],
    'ln': [
        "name list", 'comma separated list enclosed in `[]` of '
        'one or more groups that have just name and dscr keys.'
        ' e.g. `{ name: "name", desc: "description"}`'
    ],
    'lnw': ["name list+", 'name list that optionally contains a width'],
    'lp': ["parameter list", 'parameter list having default value optionally'],
    'g': ["group", "comma separated group of key:value enclosed in `{}`"],
    'lg': [
        "list of group", "comma separated group of key:value enclosed in `{}`"
        " the second entry of the list is the sub group format"
    ],
    's': ["string", "string, typically short"],
    't': [
        "text", "string, may be multi-line enclosed in `'''` "
        "may use `**bold**`, `*italic*` or `!!Reg` markup"
    ],
    'T': ["tuple", "tuple enclosed in ()"],
    'pi': ["python int", "Native Python type int (generated)"],
    'pb': ["python Bool", "Native Python type Bool (generated)"],
    'pl': ["python list", "Native Python type list (generated)"],
    'pe': ["python enum", "Native Python type enum (generated)"]
}

# ln type has list of groups with only name and description
# (was called "subunit" in cfg_validate)
ln_required = {
    'name': ['s', "name of the item"],
    'desc': ['s', "description of the item"],
}
ln_optional = {
    'width': ['d', "bit width of the item (if not 1)"],
}

# Registers list may have embedded keys
list_optone = {
    'reserved': ['d', "number of registers to reserve space for"],
    'skipto': ['d', "set next register offset to value"],
    'window': [
        'g', "group defining an address range "
        "for something other than standard registers"
    ],
    'multireg':
    ['g', "group defining registers generated "
     "from a base instance."]
}

key_use = {'r': "required", 'o': "optional", 'a': "added by tool"}