Added possibility to add missing currencies through config.

README.md

@@ -92,7 +92,7 @@ All the parameters are explained above.
 piggybank-take -r 0 0 4 from example.pb
 ```
 
-## How to see what do you have
+## How to see what you have in there
 
 ```bash
 piggybank-show FILE [ with (t | transactions)]
@@ -108,3 +108,28 @@ file.
 ```bash
 piggybank-show example.pb with t
 ```
+
+# Configuration
+
+Configuration file `piggybank.conf` is stored in directory specified by
+`$XDG_CONFIG_HOME` environment variable or, if it isn't set, in `$HOME/.config`
+on Linux and in `%APPDATA%` on Windows.
+
+By default it has following content:
+
+	default-currency = SRUB
+
+Aside from `default-currency` there is also a `currency.*` parameter. `*` is a
+currency's ISO code, e.g. `currency.RUB`, `currency.USD`, `currency.EUR` etc.
+This parameter allows you to add a currency needed for you, but not presented in
+program.
+
+Currency is defined following way:
+
+	currency.ISO = ISO;NAME;DESCRIPTION;COINS_COUNT;COINS_NAME;FACE_VALUES
+
+That is best described with an example. Here it is:
+
+	currency.SRUB = SRUB;Russian ruble (shortened);Russian Federation. Excluding coins of 1 and 5 kopek;6;10к.,50к.,1₽,2₽,5₽,10₽;10,50,100,200,500,1000
+
+Yes, long and clunky way... May be I'll come up with something better.

piggybank/__init__.py

@@ -3,7 +3,7 @@ __all__ = ["__date__", "__version__", "__author__", "__author_email__",
            "print_program_version"]
 
 
-__date__ = "5 June 2020"
+__date__ = "6 June 2020"
 __version__ = "1.0.0"
 __author__ = "Alexander \"Arav\" Andreev"
 __author_email__ = "me@arav.top"

piggybank/configuration.py

@@ -1,4 +1,14 @@
-"""An implementation of a simple key=value configuration."""
+"""An implementation of a slightly advanced key=value configuration file.
+Commentary lines are started with # symbol.
+Keys and values are separated by ' = ' (spaces are necessary).
+Keys with . symbol are splited and right part is a nested dictionary.
+Example:
+    # A commentary line
+    default_something = 10
+    currency.RUB = ...
+Above example is translated as a following dictionary:
+    { "default_something": 10, "currency": { "RUB": "..." } }
+"""
 
 from os import getenv
 from os.path import exists, join
@@ -8,7 +18,8 @@ from typing import Union
 __all__ = ["Configuration", "get_configuration_path"]
 
 
-def get_configuration_path():
+def get_configuration_path() -> str:
+    """Returns a path to where configuration is stored."""
     if system() == "Linux":
         return getenv("XDG_CONFIG_HOME") or f"{getenv('HOME')}/.config"
     elif system() == "Windows":
@@ -16,8 +27,8 @@ def get_configuration_path():
 
 
 DEFAULT_CONFIGURATION = {
-    "default-currency": "SRUB"
-}
+    "default-currency": "SRUB" }
+
 DEFAULT_CONFIGURATION_FILE = join(get_configuration_path(), "piggybank.conf")
 
 
@@ -34,7 +45,13 @@ class Configuration:
 
     def load(self) -> None:
         for line in open(self._configuration_file, 'r'):
+            if line[0] == "#":
+                continue
             key, value = line[:-1].split(" = ")
+            if key.find(".") != -1:
+                k0, k1 = key.split(".")
+                self._configuration[k0] = {k1 : value}
+            else:
                 self._configuration[key] = value
 
     def save(self) -> None:

piggybank/currencies.py

@@ -1,28 +1,19 @@
-"""Here is a dictionary of supported currencies defined. Which could be easily
-extended with new ones.
+"""Dictionary of supported currencies as instances of a Currency class.
 
-Each entry is a dictionary that has an ISO code of a currency as its key. Or it
-can be slightly differ from an ISO code to represent a modified version of a
-currency.
+Face values are stored as decimals*.
 
-Each entry consists of following fields:
-    name        -- a full name of a currency;
-    description -- usually a country where this currency is used is being
-        mentioned. Plus additional information;
-    count       -- a number of coins in a currency;
-    names       -- an array of names for each coins' face values;
-    multipliers -- an array of multipliers for each face value in a decimal*
-        format.
-
-* - Decimal is used to avoid problems of rounding float numbers. So first two
+* Decimal is used to avoid problems of rounding float numbers. So first two
 digits to the right are used to store a fraction part. You can simply divide
-this number by 100 to get a regular floating-point number.
+this number by 100 to get a floating-point number.
 """
 
+from __future__ import annotations
+from operator import mul
 from typing import Dict, List, TypedDict
 
-__all__ = ["CURRENCIES", "BaseCurrencyError", "CurrencyIsNotSupportedError",
-           "CurrenciesCoinCountMismatchError", "CurrencyMismatchError"]
+__all__ = [ "Currency", "CURRENCIES", "BaseCurrencyError", 
+            "CurrencyIsNotSupportedError", "CurrenciesCoinCountMismatchError",
+            "CurrencyMismatchError"]
 
 
 class BaseCurrencyError(Exception):
@@ -52,63 +43,106 @@ class CurrenciesCoinCountMismatchError(BaseCurrencyError):
     pass
 
 
-class Currency(TypedDict):
-    name: str
-    description: str
-    count: int
-    names: List[str]
-    multipliers: List[int]
+class Currency:
+    """Currency's representation and methods to work with it.
+
+    Arguments:
+        iso_code    -- ISO code of a currency;
+        name        -- full name of a currency;
+        description -- description of a currency;
+        coins_count -- number of face values of coins;
+        coin_names  -- list of names of face values (e.g. 1c, 5c);
+        face_values -- list of values for each face value in decimal
+                       (e.g. $476.40 is 47640);
+    """
+    def __init__(self, iso_code: str, name: str, description: str,
+                 coins_count: int, coin_names: List[str],
+                 face_values: List[int]):
+        self._iso = iso_code.upper()
+        self._name = name
+        self._description = description
+        self._coins_count = coins_count
+        self._coin_names = coin_names
+        self._face_values = face_values
+
+    @property
+    def iso(self) -> str:
+        """ISO code of a currency."""
+        return self._iso
+
+    @property
+    def name(self) -> str:
+        """Full name of a currency."""
+        return self._name
+
+    @property
+    def description(self) -> str:
+        """Description of a currency (e.g. country)."""
+        return self._description
+
+    @property
+    def count(self):
+        """Count of coins of a currency."""
+        return self._coins_count
+
+    @property
+    def coin_names(self) -> List[str]:
+        """Names of coins (usually face values, e.g. 25¢).
+        From least to most."""
+        return self._coin_names
+
+    @property
+    def face_values(self) -> List[int]:
+        """Face values of coins. From least to most."""
+        return self._face_values
+
+    def multiply(self, lst: List[int]) -> List[float]:
+        """Multiplies a list by face values. Length of list must match
+        currency's coins count."""
+        if len(lst) != len(self):
+            raise CurrenciesCoinCountMismatchError
+        return list(map(mul, lst, self.face_values))
+
+    @staticmethod
+    def from_string(currency: str) -> Currency:
+        """Creates a Currency object from its string representation."""
+        iso, name, desc, ccnt, fvn, fv = currency.split(";")
+        return Currency(iso, name, desc, int(ccnt),
+               fvn.split(","), list(map(int, fv.split(","))))
+
+    def __mul__(self, lst: List[int]) -> List[float]:
+        return self.multiply(lst)
+
+    def __len__(self) -> int:
+        return self.count
+
+    def __str__(self):
+        return f"{self.iso};{self.name};{self.description};" \
+               f"{self.count};{','.join(self.coin_names)};" \
+               f"{','.join(list(map(str, self.face_values)))}"
 
 
 CURRENCIES: Dict[str, Currency] = {
-    "RUB": {
-        "name": "Ruble",
-        "description": "Russian Federation",
-        "count": 8,
-        "names": ["1к.", "5к.", "10к.", "50к.", "1₽", "2₽", "5₽", "10₽"],
-        "multipliers": [1, 5, 10, 50, 1_00, 2_00, 5_00, 10_00]
-    },
-    "SRUB": {
-        "name": "Ruble (shortened)",
-        "description": "Russian Federation. Excluding coins of 1 and 5 kopek",
-        "count": 6,
-        "names": ["10к.", "50к.", "1₽", "2₽", "5₽", "10₽"],
-        "multipliers": [10, 50, 1_00, 2_00, 5_00, 10_00]
-    },
-    "BYN": {
-        "name": "Belarusian ruble",
-        "description": "Belarus",
-        "count": 8,
-        "names": ["1к.", "2к.", "5к.", "10к.", "20к.", "50к.", "1р.", "2р."],
-        "multipliers": [1, 2, 5, 10, 20, 50, 1_00, 2_00]
-    },
-    "UAH": {
-        "name": "Ukrainian hryvnia",
-        "description": "Ukraine",
-        "count": 10,
-        "names": ["1к.", "2к.", "5к.", "10к.", "25к.", "50к.", "₴1", "₴2",
-                  "₴5", "₴10"],
-        "multipliers": [1, 2, 5, 10, 25, 50, 1_00, 2_00, 5_00, 10_00]
-    },
-    "USD": {
-        "name": "Dollar",
-        "description": "United States of America",
-        "count": 6,
-        "names": ["1¢", "5¢", "10¢", "25¢", "50¢", "$1"],
-        "multipliers": [1, 5, 10, 25, 50, 1_00]
-    },
-    "EUR": {
-        "name": "Euro",
-        "description": "European Union",
-        "count": 8,
-        "names": ["1c", "2c", "5c", "10c", "20c", "50c", "€1", "€2"],
-        "multipliers": [1, 2, 5, 10, 20, 50, 1_00, 2_00]
-    },
-    "GBP": {
-        "name": "Pound sterling",
-        "description": "United Kingdom",
-        "count": 9,
-        "names": ["1p", "2p", "5p", "10p", "20p", "25p", "50p", "£1", "£2"],
-        "multipliers": [1, 2, 5, 10, 20, 25, 50, 1_00, 2_00]
-    }
+    "RUB": Currency("RUB", "Russian ruble", "Russian Federation", 8,
+        ["1к.", "5к.", "10к.", "50к.", "1₽", "2₽", "5₽", "10₽"],
+        [1, 5, 10, 50, 1_00, 2_00, 5_00, 10_00]),
+    "SRUB": Currency("SRUB", "Russian ruble (shortened)",
+        "Russian Federation. Excluding coins of 1 and 5 kopek.",
+        8, ["10к.", "50к.", "1₽", "2₽", "5₽", "10₽"],
+        [10, 50, 1_00, 2_00, 5_00, 10_00]),
+    "BYN": Currency("BYN", "Belarusian ruble",  "Belarus", 8,
+        ["1к.", "2к.", "5к.", "10к.", "20к.", "50к.", "1р.", "2р."],
+        [1, 2, 5, 10, 20, 50, 1_00, 2_00]),
+    "UAH": Currency("UAH", "Ukrainian hryvnia", "Ukraine", 10,
+        ["1к.", "2к.", "5к.", "10к.", "25к.", "50к.", "₴1", "₴2", "₴5", "₴10"],
+        [1, 2, 5, 10, 25, 50, 1_00, 2_00, 5_00, 10_00]),
+    "USD": Currency("USD", "US Dollar", "United States of America", 6,
+        ["1¢", "5¢", "10¢", "25¢", "50¢", "$1"],
+        [1, 5, 10, 25, 50, 1_00]),
+    "EUR": Currency("EUR", "Euro", "European Union", 8,
+        ["1c", "2c", "5c", "10c", "20c", "50c", "€1", "€2"],
+        [1, 2, 5, 10, 20, 50, 1_00, 2_00]),
+    "GBP": Currency("GBP",  "Pound sterling", "United Kingdom", 9,
+        ["1p", "2p", "5p", "10p", "20p", "25p", "50p", "£1", "£2"],
+        [1, 2, 5, 10, 20, 25, 50, 1_00, 2_00])
 }