Implemented currency formatting and parsing.

matemat/webserver/httpd.py

@@ -17,7 +17,7 @@ import jinja2
 from matemat import __version__ as matemat_version
 from matemat.exceptions import HttpException
 from matemat.webserver import RequestArguments, PageletResponse, RedirectResponse, TemplateResponse
-from matemat.webserver.util import parse_args
+from matemat.webserver.util import parse_args, format_chf
 
 #
 # Python internal class hacks
@@ -117,8 +117,9 @@ class MatematHTTPServer(HTTPServer):
         # Set up the Jinja2 environment
         self.jinja_env: jinja2.Environment = jinja2.Environment(
             loader=jinja2.FileSystemLoader(os.path.abspath(templateroot)),
-            autoescape=jinja2.select_autoescape(default=True)
+            autoescape=jinja2.select_autoescape(default=True),
         )
+        self.jinja_env.filters['chf'] = format_chf
         # Set up logger
         self.logger: logging.Logger = logging.getLogger('matemat.webserver')
         self.logger.setLevel(log_level)

matemat/webserver/pagelets/modproduct.py

@@ -8,6 +8,7 @@ from matemat.webserver import pagelet, RequestArguments, PageletResponse, Redire
 from matemat.db import MatematDatabase
 from matemat.primitives import Product
 from matemat.exceptions import DatabaseConsistencyError, HttpException
+from matemat.webserver.util import parse_chf
 
 
 @pagelet('/modproduct')
@@ -60,8 +61,8 @@ def handle_change(args: RequestArguments, product: Product, db: MatematDatabase,
         if 'name' not in args or 'pricemember' not in args or 'pricenonmember' not in args or 'stock' not in args:
             return
         name = str(args.name)
-        price_member = int(str(args.pricemember))
-        price_non_member = int(str(args.pricenonmember))
+        price_member = parse_chf(str(args.pricemember))
+        price_non_member = parse_chf(str(args.pricenonmember))
         stock = int(str(args.stock))
         try:
             db.change_product(product,

matemat/webserver/pagelets/moduser.py

@@ -8,6 +8,7 @@ from matemat.webserver import pagelet, RequestArguments, PageletResponse, Redire
 from matemat.db import MatematDatabase
 from matemat.primitives import User
 from matemat.exceptions import DatabaseConsistencyError, HttpException
+from matemat.webserver.util import parse_chf
 
 
 @pagelet('/moduser')
@@ -62,7 +63,7 @@ def handle_change(args: RequestArguments, user: User, db: MatematDatabase, confi
         username = str(args.username)
         email = str(args.email)
         password = str(args.password)
-        balance = int(str(args.balance))
+        balance = parse_chf(str(args.balance))
         is_member = 'ismember' in args
         is_admin = 'isadmin' in args
         if len(email) == 0:

matemat/webserver/util.py

@@ -136,3 +136,53 @@ def parse_args(request: str, postbody: Optional[bytes] = None, enctype: str = 't
             raise ValueError(f'Unsupported Content-Type: {enctype}')
     # Return the path and the parsed arguments
     return tokens.path, args
+
+
+def format_chf(value: int, with_currencysign: bool = True) -> str:
+    """
+    Formats a centime value into a commonly understood representation ("CHF -13.37").
+
+    :param value: The value to format, in centimes.
+    :param with_currencysign: Whether to include the currency prefix ("CHF ") in the output.
+    :return: A human-readable string representation.
+    """
+    sign: str = ''
+    if value < 0:
+        # As // and % round towards -Inf, convert into a positive value and prepend the negative sign
+        sign = '-'
+        value = -value
+    # Split into full francs and fractions (centimes)
+    full: int = value // 100
+    frac: int = value % 100
+    csign: str = 'CHF ' if with_currencysign else ''
+    # Put it all together; centimes are always padded with 2 zeros
+    return f'{csign}{sign}{full}.{frac:02}'
+
+
+def parse_chf(value: str) -> int:
+    """
+    Parse a currency value into machine-readable format (integer centimes).  The prefix "CHF", the decimal point, and
+    digits after the decimal point are optional.
+
+    :param value: The value to parse.
+    :return: An integer representation of the value.
+    :raises: Value error: If more than two digits after the decimal point are present.
+    """
+    value = value.strip()
+    if value.startswith('CHF'):
+        value = value[3:]
+    value = value.strip()
+    if '.' not in value:
+        return int(value) * 100
+    full, frac = value.split('.', 1)
+    if len(frac) > 2:
+        raise ValueError('Needs max. 2 digits after decimal point')
+    elif len(frac) < 2:
+        frac = frac + '0' * (2 - len(frac))
+    ifrac: int = int(frac)
+    ifull: int = int(full)
+    if ifrac < 0:
+        raise ValueError('Fraction part must not be negative.')
+    if ifull < 0:
+        ifrac = -ifrac
+    return ifull * 100 + ifrac

templates/modproduct.html

@@ -15,10 +15,10 @@
         <input id="modproduct-name" type="text" name="name" value="{{ product.name }}" /><br/>
 
         <label for="modproduct-price-member">Member price: </label>
-        <input id="modproduct-price-member" type="text" name="pricemember" value="{{ product.price_member }}" /><br/>
+        CHF <input id="modproduct-price-member" type="number" step="0.01" name="pricemember" value="{{ product.price_member|chf(False) }}" /><br/>
 
         <label for="modproduct-price-non-member">Non-member price: </label>
-        <input id="modproduct-price-non-member" type="text" name="pricenonmember" value="{{ product.price_non_member }}" /><br/>
+        CHF <input id="modproduct-price-non-member" type="number" step="0.01" name="pricenonmember" value="{{ product.price_non_member|chf(False) }}" /><br/>
 
         <label for="modproduct-balance">Stock: </label>
         <input id="modproduct-balance" name="stock" type="text" value="{{ product.stock }}" /><br/>

templates/moduser.html

@@ -27,7 +27,7 @@
         <input id="moduser-account-isadmin" name="isadmin" type="checkbox" {% if user.is_admin %} checked="checked" {% endif %}/><br/>
 
         <label for="moduser-account-balance">Balance: </label>
-        <input id="moduser-account-balance" name="balance" type="text" value="{{ user.balance }}" /><br/>
+        CHF <input id="moduser-account-balance" name="balance" type="number" step="0.01" value="{{ user.balance|chf(False) }}" /><br/>
 
         <label for="moduser-account-avatar">
             <img height="150" src="/upload/thumbnails/users/{{ user.id }}.png" alt="Avatar of {{ user.name }}" />

templates/productlist.html

@@ -9,7 +9,7 @@
 
 {% block main %}
 
-Your balance: {{ authuser.balance }}
+Your balance: {{ authuser.balance|chf }}
 <br/>
 <a href="/deposit?n=100">Deposit CHF 1</a><br/>
 <a href="/deposit?n=1000">Deposit CHF 10</a><br/>
@@ -20,9 +20,9 @@ Your balance: {{ authuser.balance }}
         <span class="thumblist-title">{{ product.name }}</span>
         <span class="thumblist-detail">Price:
             {% if authuser.is_member %}
-            {{ product.price_member }}
+            {{ product.price_member|chf }}
             {% else %}
-            {{ product.price_non_member }}
+            {{ product.price_non_member|chf }}
             {% endif %}
             ; Stock: {{ product.stock }}</span><br/>
         <div class="imgcontainer">