first commit

2026-06-03 12:36:51 +02:00
commit 3ab205b769
22 changed files with 1261 additions and 0 deletions
@@ -0,0 +1,396 @@
+from __future__ import annotations
+
+import csv
+import io
+import math
+import os
+import re
+from datetime import datetime
+from pathlib import Path
+
+import httpx
+from bs4 import BeautifulSoup
+from fastapi import FastAPI, WebSocket, WebSocketDisconnect, Response
+from fastapi.responses import HTMLResponse, StreamingResponse, JSONResponse
+from fastapi.staticfiles import StaticFiles
+from reportlab.lib import colors
+from reportlab.lib.pagesizes import A4, landscape
+from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
+from reportlab.lib.units import cm
+from reportlab.pdfbase import pdfmetrics
+from reportlab.pdfbase.ttfonts import TTFont
+from reportlab.platypus import SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle, PageBreak
+from reportlab.graphics.shapes import Drawing, Line, PolyLine, Rect, String, Wedge
+
+from .models import SimulationRequest
+from .simulator import simulate
+
+BASE_DIR = Path(__file__).resolve().parent
+EXPORT_DIR = Path(os.environ.get("MORTGAGE_EXPORT_DIR", "./app/exports"))
+EXPORT_DIR.mkdir(exist_ok=True)
+
+FONT_DIR = BASE_DIR / "static" / "fonts"
+FONT_PATH = FONT_DIR / "DejaVuSans.ttf"
+FONT_BOLD_PATH = FONT_DIR / "DejaVuSans-Bold.ttf"
+FONT_OBLIQUE_PATH = FONT_DIR / "DejaVuSans-Oblique.ttf"
+
+if FONT_PATH.exists():
+    pdfmetrics.registerFont(TTFont("AppFont", str(FONT_PATH)))
+    APP_FONT = "AppFont"
+
+    if FONT_BOLD_PATH.exists():
+        pdfmetrics.registerFont(TTFont("AppFont-Bold", str(FONT_BOLD_PATH)))
+        APP_FONT_BOLD = "AppFont-Bold"
+    else:
+        APP_FONT_BOLD = APP_FONT
+
+    if FONT_OBLIQUE_PATH.exists():
+        pdfmetrics.registerFont(TTFont("AppFont-Oblique", str(FONT_OBLIQUE_PATH)))
+        APP_FONT_OBLIQUE = "AppFont-Oblique"
+    else:
+        APP_FONT_OBLIQUE = APP_FONT
+else:
+    APP_FONT = "Helvetica"
+    APP_FONT_BOLD = "Helvetica-Bold"
+    APP_FONT_OBLIQUE = "Helvetica-Oblique"
+
+app = FastAPI(title="Symulator kredytu hipotecznego", version="1.0.0")
+app.mount("/static", StaticFiles(directory=BASE_DIR / "static"), name="static")
+
+
+@app.middleware("http")
+async def no_cache_headers(request, call_next):
+    response = await call_next(request)
+    response.headers["Cache-Control"] = "no-store, no-cache, must-revalidate"
+    return response
+
+
+@app.get("/favicon.ico")
+def favicon() -> Response:
+    return Response(status_code=204)
+
+
+@app.get("/", response_class=HTMLResponse)
+def index() -> str:
+    return (BASE_DIR / "static" / "index.html").read_text(encoding="utf-8")
+
+
+@app.post("/api/simulate")
+def api_simulate(req: SimulationRequest):
+    return simulate(req)
+
+
+@app.websocket("/ws/simulate")
+async def ws_simulate(websocket: WebSocket):
+    await websocket.accept()
+    try:
+        while True:
+            data = await websocket.receive_json()
+            req = SimulationRequest.model_validate(data)
+            result = simulate(req)
+            await websocket.send_json(result.model_dump())
+    except WebSocketDisconnect:
+        return
+    except Exception as exc:
+        await websocket.send_json({"error": str(exc)})
+
+
+@app.get("/api/rate/nbp")
+async def nbp_rate():
+    """Pomocniczo pobiera stopę referencyjną NBP z oficjalnej strony HTML."""
+    url = "https://nbp.pl/en/monetary-policy/mpc-decisions/interest-rates/"
+    try:
+        async with httpx.AsyncClient(timeout=10, follow_redirects=True) as client:
+            resp = await client.get(url, headers={"User-Agent": "mortgage-simulator/1.0"})
+            resp.raise_for_status()
+        soup = BeautifulSoup(resp.text, "html.parser")
+        text = " ".join(soup.get_text(" ").split())
+        patterns = [
+            r"Reference rate[^0-9]{0,80}(\d+[\.,]\d+|\d+)\s*%",
+            r"minimum money market intervention rate[^0-9]{0,80}(\d+[\.,]\d+|\d+)\s*%",
+        ]
+        for pattern in patterns:
+            match = re.search(pattern, text, flags=re.IGNORECASE)
+            if match:
+                value = float(match.group(1).replace(",", "."))
+                return {"source": "NBP", "url": url, "rate": value, "fetched_at": datetime.utcnow().isoformat() + "Z"}
+        return JSONResponse({"error": "Nie znaleziono stopy w treści strony NBP", "url": url}, status_code=502)
+    except Exception as exc:
+        return JSONResponse({"error": str(exc), "url": url}, status_code=502)
+
+
+@app.post("/api/export/csv")
+def export_csv(req: SimulationRequest):
+    result = simulate(req)
+    buf = io.StringIO()
+    writer = csv.writer(buf, delimiter=";")
+    writer.writerow(["miesiac", "oprocentowanie", "rata", "kapital", "odsetki", "nadplata", "saldo"])
+    for row in result.schedule:
+        writer.writerow([row.month, row.rate, row.payment, row.principal_part, row.interest_part, row.overpayment, row.remaining])
+    writer.writerow([])
+    writer.writerow(["Podsumowanie"])
+    for key, value in result.summary.model_dump().items():
+        writer.writerow([key, value])
+    data = buf.getvalue().encode("utf-8-sig")
+    return StreamingResponse(
+        io.BytesIO(data),
+        media_type="text/csv",
+        headers={"Content-Disposition": "attachment; filename=symulacja-kredytu.csv"},
+    )
+
+
+def _money(value: float) -> str:
+    return f"{value:,.2f} PLN".replace(",", " ")
+
+
+def _pct(value: float) -> str:
+    return f"{value:.2f}%"
+
+
+def _repeat_label(value: str) -> str:
+    return {"once": "jednorazowo", "monthly": "co miesiac", "yearly": "co rok"}.get(value, value)
+
+
+def _effect_label(value: str) -> str:
+    return {"shorten": "skrocenie okresu", "lower_payment": "zmniejszenie raty"}.get(value, value)
+
+
+def _installment_label(value: str) -> str:
+    return {"equal": "rowne", "decreasing": "malejace"}.get(value, value)
+
+
+def _add_page_number(canvas_obj, doc):
+    canvas_obj.saveState()
+    canvas_obj.setFont(APP_FONT, 7)
+    canvas_obj.setFillColor(colors.HexColor("#6b7280"))
+    canvas_obj.drawString(1.4 * cm, 0.9 * cm, "Symulator edukacyjny - wyniki orientacyjne")
+    canvas_obj.drawRightString(A4[0] - 1.4 * cm, 0.9 * cm, f"Strona {doc.page}")
+    canvas_obj.restoreState()
+
+
+def _line_chart(rows, value_attr: str, title: str, width=480, height=165) -> Drawing:
+    drawing = Drawing(width, height)
+    margin_l, margin_r, margin_b, margin_t = 42, 12, 24, 24
+    plot_w = width - margin_l - margin_r
+    plot_h = height - margin_t - margin_b
+    x0, y0 = margin_l, margin_b
+    values = [float(getattr(r, value_attr)) for r in rows]
+    if not values:
+        values = [0]
+    max_v = max(values) or 1
+    count = max(len(values) - 1, 1)
+
+    drawing.add(String(0, height - 12, title, fontName=APP_FONT_BOLD, fontSize=9, fillColor=colors.HexColor("#111827")))
+    drawing.add(Line(x0, y0, x0, y0 + plot_h, strokeColor=colors.HexColor("#9ca3af"), strokeWidth=0.7))
+    drawing.add(Line(x0, y0, x0 + plot_w, y0, strokeColor=colors.HexColor("#9ca3af"), strokeWidth=0.7))
+    for i in range(1, 5):
+        gy = y0 + plot_h * i / 4
+        drawing.add(Line(x0, gy, x0 + plot_w, gy, strokeColor=colors.HexColor("#e5e7eb"), strokeWidth=0.4))
+        label = _money(max_v * i / 4).replace(" PLN", "")
+        drawing.add(String(2, gy - 3, label, fontName=APP_FONT, fontSize=6, fillColor=colors.HexColor("#6b7280")))
+    points = []
+    step = max(1, math.ceil(len(values) / 420))
+    sampled = values[::step]
+    sampled_count = max(len(sampled) - 1, 1)
+    for idx, value in enumerate(sampled):
+        x = x0 + plot_w * idx / sampled_count
+        y = y0 + plot_h * (value / max_v)
+        points.extend([x, y])
+    drawing.add(PolyLine(points, strokeColor=colors.HexColor("#2563eb"), strokeWidth=1.4))
+    drawing.add(String(x0, 6, "1", fontName=APP_FONT, fontSize=6, fillColor=colors.HexColor("#6b7280")))
+    drawing.add(String(x0 + plot_w - 18, 6, str(len(values)), fontName=APP_FONT, fontSize=6, fillColor=colors.HexColor("#6b7280")))
+    return drawing
+
+
+def _bar_chart(yearly: dict[int, float], title: str, width=480, height=165) -> Drawing:
+    drawing = Drawing(width, height)
+    margin_l, margin_r, margin_b, margin_t = 42, 12, 24, 24
+    plot_w = width - margin_l - margin_r
+    plot_h = height - margin_t - margin_b
+    x0, y0 = margin_l, margin_b
+    items = list(yearly.items())[:35]
+    max_v = max([v for _, v in items], default=1) or 1
+    drawing.add(String(0, height - 12, title, fontName=APP_FONT_BOLD, fontSize=9, fillColor=colors.HexColor("#111827")))
+    drawing.add(Line(x0, y0, x0, y0 + plot_h, strokeColor=colors.HexColor("#9ca3af"), strokeWidth=0.7))
+    drawing.add(Line(x0, y0, x0 + plot_w, y0, strokeColor=colors.HexColor("#9ca3af"), strokeWidth=0.7))
+    for i in range(1, 5):
+        gy = y0 + plot_h * i / 4
+        drawing.add(Line(x0, gy, x0 + plot_w, gy, strokeColor=colors.HexColor("#e5e7eb"), strokeWidth=0.4))
+    if items:
+        gap = 2
+        bar_w = max(3, (plot_w / len(items)) - gap)
+        for idx, (year, value) in enumerate(items):
+            bh = plot_h * value / max_v
+            x = x0 + idx * (plot_w / len(items)) + gap / 2
+            drawing.add(Rect(x, y0, bar_w, bh, fillColor=colors.HexColor("#64748b"), strokeColor=None))
+            if len(items) <= 25 or idx % 2 == 0:
+                drawing.add(String(x, 6, str(year), fontName=APP_FONT, fontSize=5.5, fillColor=colors.HexColor("#6b7280")))
+    return drawing
+
+
+def _pie_chart(parts: list[tuple[str, float, str]], title: str, width=240, height=165) -> Drawing:
+    drawing = Drawing(width, height)
+    drawing.add(String(0, height - 12, title, fontName=APP_FONT_BOLD, fontSize=9, fillColor=colors.HexColor("#111827")))
+    total = sum(v for _, v, _ in parts) or 1
+    cx, cy, r = 65, 78, 45
+    start = 90
+    for name, value, color in parts:
+        extent = 360 * value / total
+        drawing.add(Wedge(cx, cy, r, start, start + extent, fillColor=colors.HexColor(color), strokeColor=colors.white, strokeWidth=0.5))
+        start += extent
+    ly = height - 38
+    for name, value, color in parts:
+        drawing.add(Rect(130, ly - 2, 7, 7, fillColor=colors.HexColor(color), strokeColor=None))
+        pct = value / total * 100
+        drawing.add(String(142, ly, f"{name}: {pct:.1f}%", fontName=APP_FONT, fontSize=7, fillColor=colors.HexColor("#111827")))
+        ly -= 14
+    return drawing
+
+
+@app.post("/api/export/pdf")
+def export_pdf(req: SimulationRequest):
+    result = simulate(req)
+    buffer = io.BytesIO()
+    doc = SimpleDocTemplate(
+        buffer,
+        pagesize=A4,
+        rightMargin=1.2 * cm,
+        leftMargin=1.2 * cm,
+        topMargin=1.3 * cm,
+        bottomMargin=1.4 * cm,
+        title="Symulacja kredytu hipotecznego",
+    )
+    styles = getSampleStyleSheet()
+    for style in styles.byName.values():
+        style.fontName = APP_FONT
+    styles["Title"].fontName = APP_FONT_BOLD
+    styles["Heading2"].fontName = APP_FONT_BOLD
+    styles.add(ParagraphStyle(name="Small", parent=styles["Normal"], fontSize=8, leading=10, fontName=APP_FONT))
+    styles.add(ParagraphStyle(name="Tiny", parent=styles["Normal"], fontSize=6.7, leading=8, fontName=APP_FONT))
+    story = []
+
+    story.append(Paragraph("Symulacja kredytu hipotecznego - pelny raport", styles["Title"]))
+    story.append(Paragraph(f"Wygenerowano: {datetime.now().strftime('%Y-%m-%d %H:%M')}", styles["Small"]))
+    story.append(Spacer(1, 0.25 * cm))
+
+    params = [
+        ["Kwota kredytu", _money(req.principal), "Okres", f"{req.years} lat"],
+        ["Stopa bazowa", _pct(req.base_rate), "Marza", _pct(req.margin)],
+        ["Oprocentowanie startowe", _pct(req.base_rate + req.margin), "Typ rat", _installment_label(req.installment_type.value)],
+        ["Efekt nadplat", _effect_label(req.overpayment_effect.value), "Liczba rat po symulacji", str(result.summary.months)],
+    ]
+    story.append(Paragraph("Parametry wejściowe", styles["Heading2"]))
+    story.append(Table(params, colWidths=[4.9 * cm, 3.4 * cm, 4.4 * cm, 3.9 * cm], style=TableStyle([
+        ("GRID", (0, 0), (-1, -1), 0.25, colors.HexColor("#cbd5e1")),
+        ("BACKGROUND", (0, 0), (-1, -1), colors.HexColor("#f8fafc")),
+        ("FONTNAME", (0, 0), (-1, -1), APP_FONT),
+        ("FONTNAME", (0, 0), (0, -1), APP_FONT_BOLD),
+        ("FONTNAME", (2, 0), (2, -1), APP_FONT_BOLD),
+        ("FONTSIZE", (0, 0), (-1, -1), 7.4),
+        ("VALIGN", (0, 0), (-1, -1), "TOP"),
+    ])))
+    story.append(Spacer(1, 0.35 * cm))
+
+    s = result.summary
+    summary = [
+        ["Liczba rat", s.months, "Bazowo", s.baseline_months],
+        ["Suma zaplacona", _money(s.total_paid), "Suma odsetek", _money(s.total_interest)],
+        ["Oszczednosc na odsetkach", _money(s.interest_saved), "Skrocenie okresu", f"{s.months_saved} mies."],
+        ["Suma nadplat", _money(s.total_overpayment), "Srednia / maks. rata", f"{_money(s.average_payment)} / {_money(s.max_payment)}"],
+    ]
+    story.append(Paragraph("Podsumowanie", styles["Heading2"]))
+    story.append(Table(summary, colWidths=[4.9 * cm, 3.4 * cm, 4.4 * cm, 3.9 * cm], style=TableStyle([
+        ("GRID", (0, 0), (-1, -1), 0.25, colors.HexColor("#cbd5e1")),
+        ("BACKGROUND", (0, 0), (-1, -1), colors.HexColor("#ffffff")),
+        ("FONTNAME", (0, 0), (-1, -1), APP_FONT),
+        ("FONTNAME", (0, 0), (0, -1), APP_FONT_BOLD),
+        ("FONTNAME", (2, 0), (2, -1), APP_FONT_BOLD),
+        ("FONTSIZE", (0, 0), (-1, -1), 7.4),
+        ("VALIGN", (0, 0), (-1, -1), "TOP"),
+    ])))
+    story.append(Spacer(1, 0.35 * cm))
+
+    story.append(Paragraph("Wykresy", styles["Heading2"]))
+    yearly = {}
+    for row in result.schedule:
+        year = math.ceil(row.month / 12)
+        yearly[year] = yearly.get(year, 0.0) + row.interest_part
+    story.append(_line_chart(result.schedule, "remaining", "Saldo kredytu w czasie"))
+    story.append(Spacer(1, 0.15 * cm))
+    story.append(_line_chart(result.schedule, "payment", "Rata w czasie"))
+    story.append(Spacer(1, 0.15 * cm))
+    story.append(Table([[
+        _bar_chart(yearly, "Odsetki rocznie", width=285, height=150),
+        _pie_chart([
+            ("Kapital", req.principal, "#2563eb"),
+            ("Odsetki", s.total_interest, "#64748b"),
+            ("Nadplaty", s.total_overpayment, "#16a34a"),
+        ], "Struktura kosztow", width=220, height=150),
+    ]], colWidths=[9.6 * cm, 7.3 * cm]))
+    story.append(PageBreak())
+
+    story.append(Paragraph("Zmienne oprocentowanie", styles["Heading2"]))
+    rate_rows = [["Od miesiaca", "Oprocentowanie roczne"]]
+    rate_rows.append(["1", _pct(req.base_rate + req.margin)])
+    for change in sorted(req.rate_changes, key=lambda x: x.month):
+        rate_rows.append([str(change.month), _pct(change.annual_rate)])
+    story.append(Table(rate_rows, repeatRows=1, colWidths=[4 * cm, 6 * cm], style=TableStyle([
+        ("BACKGROUND", (0, 0), (-1, 0), colors.HexColor("#e5e7eb")),
+        ("GRID", (0, 0), (-1, -1), 0.25, colors.HexColor("#cbd5e1")),
+        ("FONTNAME", (0, 0), (-1, -1), APP_FONT),
+        ("FONTNAME", (0, 0), (-1, 0), APP_FONT_BOLD),
+        ("FONTSIZE", (0, 0), (-1, -1), 8),
+    ])))
+    story.append(Spacer(1, 0.35 * cm))
+
+    story.append(Paragraph("Nadplaty", styles["Heading2"]))
+    over_rows = [["Miesiac", "Kwota", "Powtarzanie", "Do miesiaca"]]
+    if req.overpayments:
+        for op in sorted(req.overpayments, key=lambda x: x.month):
+            over_rows.append([str(op.month), _money(op.amount), _repeat_label(op.repeat), str(op.until_month or "-")])
+    else:
+        over_rows.append(["-", "-", "-", "-"])
+    story.append(Table(over_rows, repeatRows=1, colWidths=[3 * cm, 4 * cm, 4 * cm, 4 * cm], style=TableStyle([
+        ("BACKGROUND", (0, 0), (-1, 0), colors.HexColor("#e5e7eb")),
+        ("GRID", (0, 0), (-1, -1), 0.25, colors.HexColor("#cbd5e1")),
+        ("FONTNAME", (0, 0), (-1, -1), APP_FONT),
+        ("FONTNAME", (0, 0), (-1, 0), APP_FONT_BOLD),
+        ("FONTSIZE", (0, 0), (-1, -1), 8),
+    ])))
+    story.append(PageBreak())
+
+    story.append(Paragraph("Kompletny harmonogram wszystkich rat", styles["Heading2"]))
+    schedule_rows = [["Mies.", "Oproc.", "Rata", "Kapital", "Odsetki", "Nadplata", "Saldo"]]
+    for row in result.schedule:
+        schedule_rows.append([
+            row.month,
+            _pct(row.rate),
+            _money(row.payment),
+            _money(row.principal_part),
+            _money(row.interest_part),
+            _money(row.overpayment),
+            _money(row.remaining),
+        ])
+    table = Table(schedule_rows, repeatRows=1, colWidths=[1.35 * cm, 1.7 * cm, 2.55 * cm, 2.55 * cm, 2.55 * cm, 2.55 * cm, 3.0 * cm])
+    table.setStyle(TableStyle([
+        ("BACKGROUND", (0, 0), (-1, 0), colors.HexColor("#e5e7eb")),
+        ("TEXTCOLOR", (0, 0), (-1, 0), colors.HexColor("#111827")),
+        ("GRID", (0, 0), (-1, -1), 0.2, colors.HexColor("#cbd5e1")),
+        ("FONTNAME", (0, 0), (-1, -1), APP_FONT),
+        ("FONTNAME", (0, 0), (-1, 0), APP_FONT_BOLD),
+        ("FONTSIZE", (0, 0), (-1, -1), 6.5),
+        ("LEADING", (0, 0), (-1, -1), 7.5),
+        ("ALIGN", (0, 1), (-1, -1), "RIGHT"),
+        ("ALIGN", (0, 0), (-1, 0), "CENTER"),
+        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
+        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [colors.white, colors.HexColor("#f8fafc")]),
+    ]))
+    story.append(table)
+
+    doc.build(story, onFirstPage=_add_page_number, onLaterPages=_add_page_number)
+    buffer.seek(0)
+    return Response(
+        buffer.read(),
+        media_type="application/pdf",
+        headers={"Content-Disposition": "attachment; filename=symulacja-kredytu.pdf"},
+    )