demo_pdf.py

"""Generate a demo event log and render a tagged PDF/A-3a report.pdf (EXP-06).

Needs the optional 'pdf' extra (`pip install -e '.[pdf]'`; weasyprint>=67, which
itself needs a >=3.10 host interpreter -- see
docs/adr/0004-weasyprint-for-tagged-pdf-a-export.md). Reuses the same synthetic,
no-hardware, no-audio session as scripts/demo_report.py. Handy for eyeballing
output and for `make pdf-a11y`.

Structural tags only, not a verified PDF/UA conformance claim -- see
report/pdf_export.py and the ADR for exactly what is, and is not, verified.
"""

from __future__ import annotations

import sys
from pathlib import Path

ROOT = Path(__file__).resolve().parent.parent
sys.path.insert(0, str(ROOT))

from monitor.capture import LoudRegion, synthetic_session  # noqa: E402
from monitor.config import Config  # noqa: E402
from monitor.service import run_pipeline  # noqa: E402
from report.render import generate_report_from_db  # noqa: E402
from store import EventStore  # noqa: E402

DB = ROOT / "demo.db"
OUT = ROOT / "report.pdf"

if DB.exists():
    DB.unlink()

config = Config(
    db_path=str(DB),
    tagging=True,
    device_label="demo-pi",
    mic_model="USB mic (demo)",
    placement_note="Demo: synthetic session, no real microphone.",
)
labels = [
    LoudRegion(2.0, 6.0, 0.30),
    LoudRegion(20.0, 23.0, 0.45),
    LoudRegion(40.0, 41.0, 0.20),
]
with EventStore(DB) as store:
    store.add_calibration(
        config.calibration_offset,
        config.calibration_note,
        effective_from=0.0,
    )
    sid = store.start_session(
        started_at=0.0,
        device_label=config.device_label,
        mic_model=config.mic_model,
        placement_note=config.placement_note,
        tz=config.tz,
        calibration_offset=config.calibration_offset,
        calibration_note=config.calibration_note,
        app_version="0.1.0",
    )
    events = list(
        run_pipeline(
            synthetic_session(60.0, labels, frame_size=config.frame_size),
            config,
            store,
            session_id=sid,
        )
    )
    store.update_session(sid, frames_seen=600, frames_dropped=0, ended_at=60.0)

html = generate_report_from_db(str(DB), config, generated_at="(demo) 2026-01-01 12:00 UTC")

from report.pdf_export import (  # noqa: E402
    PdfExportUnavailable,
    TaggedPdfGenerationError,
    write_tagged_pdf,
)

try:
    n = write_tagged_pdf(html, OUT)
    print(f"Wrote {OUT.relative_to(ROOT)} ({n} bytes, tagged PDF/A-3a) from demo session.")
except (PdfExportUnavailable, TaggedPdfGenerationError) as exc:
    print(f"Skipped {OUT.relative_to(ROOT)}: {exc}")
    raise SystemExit(1) from exc