🎉 Initial commit

app/main.py

@@ -0,0 +1,181 @@
+from __future__ import annotations
+
+import base64
+import io
+import json
+import math
+import os
+from datetime import date
+from pathlib import Path
+from typing import Literal
+from urllib.parse import quote
+
+import qrcode
+from fastapi import FastAPI, Query, Request
+from fastapi.responses import HTMLResponse, PlainTextResponse
+from fastapi.staticfiles import StaticFiles
+from fastapi.templating import Jinja2Templates
+from pydantic import BaseModel, Field, field_validator, model_validator
+
+import uvicorn
+
+
+class CostItem(BaseModel):
+    post: str = Field(min_length=1)
+    amount: float = Field(ge=0)
+    period: Literal["month", "year"] = "month"
+    ratio: float = Field(ge=0, le=1)
+    comment: str | None = None
+
+    @property
+    def monthly_amount(self) -> float:
+        return self.amount / 12 if self.period == "year" else self.amount
+
+    @property
+    def monthly_share(self) -> float:
+        return self.monthly_amount * self.ratio
+
+
+class SwishConfig(BaseModel):
+    payee: str = Field(min_length=8, description="Swishnummer, helst med landskod utan +, t.ex. 46701234567")
+    message_prefix: str = "Bohemma"
+    lock_mask: int = Field(default=0, ge=0, description="0 låser mottagare, belopp och meddelande i Swish-QR-formatet.")
+
+    @field_validator("payee")
+    @classmethod
+    def normalize_payee(cls, value: str) -> str:
+        return value.replace("+", "").replace(" ", "").replace("-", "")
+
+
+class PaymentConfig(BaseModel):
+    income_ratio: float = Field(default=0.30, ge=0, le=1)
+    max_amount: float | None = Field(default=None, ge=0)
+    round_to: float = Field(default=1.0, ge=0.0)
+
+
+class AppConfig(BaseModel):
+    title: str = "Bo hemma-avi"
+    currency: str = "SEK"
+    swish: SwishConfig
+    payment: PaymentConfig = PaymentConfig()
+    items: list[CostItem]
+
+    @model_validator(mode="after")
+    def ensure_items(self) -> "AppConfig":
+        if not self.items:
+            raise ValueError("config.json måste innehålla minst en kostnadspost i items.")
+        return self
+
+
+app = FastAPI(title="Bo hemma-avi")
+app.mount("/static", StaticFiles(directory="app/static"), name="static")
+templates = Jinja2Templates(directory="app/templates")
+
+
+def config_path() -> Path:
+    #return Path(os.getenv("CONFIG_PATH", "/app/config.json"))
+    return Path(os.getenv("CONFIG_PATH", "config.json"))
+
+
+def load_config() -> AppConfig:
+    path = config_path()
+    with path.open("r", encoding="utf-8") as f:
+        data = json.load(f)
+    return AppConfig.model_validate(data)
+
+
+def money(value: float) -> str:
+    rounded = round(value, 2)
+    if rounded == int(rounded):
+        return f"{int(rounded):,}".replace(",", " ")
+    return f"{rounded:,.2f}".replace(",", " ").replace(".", ",")
+
+
+def swish_amount(value: float) -> str:
+    return f"{value:.2f}"#.replace(".", ",")
+
+
+def round_to(value: float, round_to: float) -> float:
+    return float(math.ceil(value / round_to) * round_to)
+
+
+def current_period() -> str:
+    today = date.today()
+    return f"{today.year}-{today.month:02d}"
+
+
+def build_swish_payload(payee: str, amount: float, message: str, lock_mask: int) -> str:
+    # Swish QR text payload. Meddelandet URL-kodas, mellanslag blir %20.
+    return f"C{payee};{swish_amount(amount)};{quote(message, safe=' ')};{lock_mask}"
+
+
+def qr_data_uri(payload: str) -> str:
+    qr = qrcode.QRCode(
+        version=None,
+        error_correction=qrcode.ERROR_CORRECT_M,
+        box_size=10,
+        border=3,
+    )
+    qr.add_data(payload)
+    qr.make(fit=True)
+    image = qr.make_image(fill_color="black", back_color="white")
+    buffer = io.BytesIO()
+    image.save(buffer, "PNG")
+    encoded = base64.b64encode(buffer.getvalue()).decode("ascii")
+    return f"data:image/png;base64,{encoded}"
+
+
+@app.get("/", response_class=HTMLResponse)
+def index(request: Request, nettoinkomst: float | None = Query(default=None, ge=0)):
+    cfg = load_config()
+
+    rows = []
+    total_monthly_share = 0.0
+    for item in cfg.items:
+        row = {
+            "post": item.post,
+            "amount": item.amount,
+            "period": item.period,
+            "ratio": item.ratio,
+            "monthly_amount": item.monthly_amount,
+            "monthly_share": item.monthly_share,
+            "comment": item.comment,
+        }
+        rows.append(row)
+        total_monthly_share += item.monthly_share
+
+    calculation = None
+    if nettoinkomst is not None:
+        income_cap = nettoinkomst * cfg.payment.income_ratio
+        candidates = [total_monthly_share, income_cap]
+        if cfg.payment.max_amount is not None:
+            candidates.append(cfg.payment.max_amount)
+        amount = round_to(min(candidates), cfg.payment.round_to)
+        message = f"{cfg.swish.message_prefix} {current_period()}"
+        payload = build_swish_payload(cfg.swish.payee, amount, message, cfg.swish.lock_mask)
+        calculation = {
+            "nettoinkomst": nettoinkomst,
+            "income_ratio": cfg.payment.income_ratio,
+            "income_cap": income_cap,
+            "amount": amount,
+            "message": message,
+            "payload": payload,
+            "qr": qr_data_uri(payload),
+        }
+
+    return templates.TemplateResponse(
+        request=request,
+        name="index.html",
+        context={
+            "cfg": cfg,
+            "rows": rows,
+            "total_monthly_share": total_monthly_share,
+            "calculation": calculation,
+            "money": money,
+        },
+    )
+
+
+@app.get("/health", response_class=PlainTextResponse)
+def health() -> str:
+    return "ok"