Separate Financial Core Formulas from UI

Author: paty-oliveira

src/core/__init__.py

@@ -0,0 +1,7 @@
+from .currency import convert_currency_symbol
+from .financial_formulas import calculate_price_changes
+
+financial_calculations = {
+    "currency_symbol": convert_currency_symbol,
+    "price_changes": calculate_price_changes,
+}

src/core/currency.py

@@ -0,0 +1,25 @@
+def convert_currency_symbol(currency_symbol):
+    currency = {
+        "USD": "$",  # US Dollar
+        "EUR": "€",  # Euro
+        "JPY": "¥",  # Japanese Yen
+        "GBP": "£",  # British Pound Sterling
+        "AUD": "A$",  # Australian Dollar
+        "CAD": "C$",  # Canadian Dollar
+        "CHF": "CHF",  # Swiss Franc
+        "CNY": "¥",  # Chinese Yuan Renminbi
+        "HKD": "HK$",  # Hong Kong Dollar
+        "INR": "₹",  # Indian Rupee
+        "RUB": "₽",  # Russian Ruble
+        "BRL": "R$",  # Brazilian Real
+        "ZAR": "R",  # South African Rand
+        "KRW": "₩",  # South Korean Won
+        "MXN": "$",  # Mexican Peso
+        "SGD": "S$",  # Singapore Dollar
+        "NZD": "NZ$",  # New Zealand Dollar
+        "TRY": "₺",  # Turkish Lira
+        "SEK": "kr",  # Swedish Krona
+        "NOK": "kr",  # Norwegian Krone
+    }
+
+    return currency[currency_symbol]

src/core/financial_formulas.py

@@ -0,0 +1,2 @@
+def calculate_price_changes(current_price, previous_close_price):
+    return round((current_price - previous_close_price) / previous_close_price, 2) * 100

src/main.py

@@ -1,7 +1,9 @@
+import core
 import infra
 import ui
 
 _financial_provider = None
+_financial_calculations = None
 
 
 def initialize_financial_provider(provider_name):
@@ -10,9 +12,16 @@ def initialize_financial_provider(provider_name):
         _financial_provider = infra.financial_data_provider(provider_name)
 
 
+def initialize_financial_formulas():
+    global _financial_calculations
+    if _financial_calculations is None:
+        _financial_calculations = core.financial_calculations
+
+
 def main():
     initialize_financial_provider(infra.YAHOO)
-    ui.run(_financial_provider)
+    initialize_financial_formulas()
+    ui.run(_financial_provider, _financial_calculations)
 
 
 if __name__ == "__main__":

src/ui/__init__.py

@@ -6,7 +6,7 @@
 initial_state = {"ticker": ""}
 
 
-def run(financial_data):
+def run(financial_data, financial_calculations):
     st.set_page_config(
         page_title="Stock Analysis Dashboard",
         page_icon=":chart_with_upwards_trend:",
@@ -19,5 +19,5 @@ def run(financial_data):
             st.session_state[k] = v
 
     # performs the rendering
-    render_layout(financial_data)
+    render_layout(financial_data, financial_calculations)
     render_sidebar()

src/ui/layout.py

@@ -4,14 +4,14 @@
 from .raw_content import homepage_content, footer_content, not_found_ticker_content
 
 
-def render(financial_data):
+def render(financial_data, financial_calculations):
     ticker = st.session_state["ticker"]
     if not ticker:
         render_homepage()
     elif not financial_data.is_valid_ticker(ticker):
         render_invalid_ticker_placeholder()
     else:
-        render_stock_info(financial_data)
+        render_stock_info(financial_data, financial_calculations)
         render_footer()
 
 
@@ -27,9 +27,9 @@ def render_footer():
     st.markdown(footer_content, unsafe_allow_html=True)
 
 
-def render_stock_info(financial_data):
+def render_stock_info(financial_data, financial_calculations):
     # Render header
-    render_header(financial_data)
+    render_header(financial_data, financial_calculations)
     # Renders tabs
     tab_titles = ["Overview", "Balance Sheet", "Income Statement", "CashFlow"]
     tabs_renderings = [
@@ -44,7 +44,7 @@ def render_stock_info(financial_data):
             render_action(financial_data)
 
 
-def render_header(financial_data):
+def render_header(financial_data, financial_calculations):
     stock_info = financial_data.get_stock_info(
         st.session_state["ticker"],
     )
@@ -55,8 +55,11 @@ def render_header(financial_data):
     current_price = stock_info["currentPrice"]
     previous_close_price = stock_info["previousClose"]
     currency = stock_info["currency"]
-    current_price_content = f"{convert_currency_symbol(currency)}{current_price}"
-    price_diff = calculate_price_changes(current_price, previous_close_price)
+    currency_symbol = financial_calculations["currency_symbol"](currency)
+    current_price_content = f"{currency_symbol}{current_price}"
+    price_diff = financial_calculations["price_changes"](
+        current_price, previous_close_price
+    )
     price_diff_content = f"({price_diff}%)"
     price_change_content = (
         apply_text_color(price_diff_content, "red")
@@ -116,36 +119,5 @@ def render_cashflow(financial_data):
     st.dataframe(cashflow)
 
 
-def convert_currency_symbol(currency_symbol):
-    currency = {
-        "USD": "$",  # US Dollar
-        "EUR": "€",  # Euro
-        "JPY": "¥",  # Japanese Yen
-        "GBP": "£",  # British Pound Sterling
-        "AUD": "A$",  # Australian Dollar
-        "CAD": "C$",  # Canadian Dollar
-        "CHF": "CHF",  # Swiss Franc
-        "CNY": "¥",  # Chinese Yuan Renminbi
-        "HKD": "HK$",  # Hong Kong Dollar
-        "INR": "₹",  # Indian Rupee
-        "RUB": "₽",  # Russian Ruble
-        "BRL": "R$",  # Brazilian Real
-        "ZAR": "R",  # South African Rand
-        "KRW": "₩",  # South Korean Won
-        "MXN": "$",  # Mexican Peso
-        "SGD": "S$",  # Singapore Dollar
-        "NZD": "NZ$",  # New Zealand Dollar
-        "TRY": "₺",  # Turkish Lira
-        "SEK": "kr",  # Swedish Krona
-        "NOK": "kr",  # Norwegian Krone
-    }
-
-    return currency[currency_symbol]
-
-
-def calculate_price_changes(current_price, previous_close_price):
-    return round((current_price - previous_close_price) / previous_close_price, 2) * 100
-
-
 def apply_text_color(text, color):
     return f"<span style='color:{color}'>{text}</span>"