"""Runnable check for project state: round-trip, cut edits, discard pre-set."""

from __future__ import annotations

import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parents[1]))

from noteman_slicer.detect import PageDetection, System  # noqa: E402
from noteman_slicer.project import Cut, Project, default_path  # noqa: E402


def main() -> int:
    tmp = Path(__file__).with_name("_tmp")
    tmp.mkdir(exist_ok=True)
    pdf = tmp / "song.pdf"
    pdf.write_bytes(b"%PDF-1.7 not really a pdf, only its bytes are hashed")

    height = 1000
    detection = PageDetection(
        skew=-1.1,
        systems=[System(200, 400, 60.0), System(600, 800, 60.0)],
        cuts=[500],
    )
    project = Project.from_detection(pdf, [detection], [height])
    page = project.pages[0]

    # One cut between the systems, plus a boundary cut above the first and
    # below the last — so the header and footer become their own slices.
    assert len(page.cuts) == 3, [c.points for c in page.cuts]
    assert page.discards == [True, False, False, True], page.discards
    assert page.slice_count == 4
    assert project.kept_slices() == [(0, 1), (0, 2)], project.kept_slices()

    # Geometry is normalised, so it survives any change of resolution.
    assert all(0.0 <= y <= 1.0 for cut in page.cuts for _, y in cut.points)
    assert page.cuts[1].straight_y == 0.5

    # A straight cut is flat; a stepped one is not, and interpolates.
    step = Cut([(0.0, 0.20), (0.35, 0.20), (0.35, 0.40), (1.0, 0.40)])
    assert step.straight_y is None
    assert step.y_at(0.0) == 0.20
    assert step.y_at(1.0) == 0.40
    assert step.y_at(0.35) == 0.20 or step.y_at(0.35) == 0.40
    assert step.highest == 0.20 and step.lowest == 0.40

    # Adding a cut splits a slice and keeps that slice's flag on both halves.
    before = page.slice_count
    index = page.add_cut(Cut.straight(0.65))
    assert page.slice_count == before + 1
    assert index == 2, index
    assert page.discards == [True, False, False, False, True], page.discards

    # Removing it merges them again.
    page.remove_cut(index)
    assert page.slice_count == before
    assert page.discards == [True, False, False, True], page.discards

    # Round-trip.
    saved = project.save()
    assert saved == default_path(pdf), saved
    reloaded = Project.load(saved)
    assert reloaded.pages[0].skew == -1.1
    assert reloaded.pages[0].discards == page.discards
    assert [c.points for c in reloaded.pages[0].cuts] == [c.points for c in page.cuts]
    assert reloaded.source_hash == project.source_hash
    assert not reloaded.source_changed()

    # A project is spent once exported: reopening starts fresh.
    assert not reloaded.exported
    reloaded.exported = True
    reloaded.save()
    assert Project.load(saved).exported

    # A PDF edited underneath must be reported, not silently re-cut.
    pdf.write_bytes(b"%PDF-1.7 different bytes entirely")
    assert reloaded.source_changed()

    for f in (pdf, saved):
        f.unlink()
    tmp.rmdir()
    print("ok")
    return 0


if __name__ == "__main__":
    sys.exit(main())