from __future__ import annotations

import json

from quantum_learning import (
    canonical_course_steps,
    entry_notebook_path,
    project_root,
    visible_notebook_root_names,
)


def _notebook_text(path):
    data = json.loads(path.read_text())
    return "\n".join("".join(cell.get("source", [])) for cell in data.get("cells", []))


def test_start_here_is_the_only_supported_entrypoint():
    assert entry_notebook_path() == project_root() / "notebooks" / "START_HERE.ipynb"

    app_script = (project_root() / "scripts" / "app.sh").read_text()
    assert "lab/tree/notebooks/START_HERE.ipynb" in app_script


def test_visible_notebook_root_is_curated():
    notebook_root = project_root() / "notebooks"
    visible_names = sorted(path.name for path in notebook_root.iterdir() if not path.name.startswith("."))
    assert visible_names == sorted(visible_notebook_root_names())


def test_reference_notebook_is_not_part_of_the_course_tree():
    assert not (project_root() / "notebooks" / "PROFESSIONAL_PATH.ipynb").exists()
    assert not (project_root() / "notebooks" / "reference").exists()
    assert not (project_root() / "notebooks" / ".reference").exists()


def test_mainline_course_notebooks_have_navigation_guardrails():
    steps = canonical_course_steps()
    for index, step in enumerate(steps):
        path = project_root() / step.path
        text = _notebook_text(path)
        assert "<!-- COURSE_NAV_TOP -->" in text
        assert "<!-- COURSE_NAV_BOTTOM -->" in text
        assert "What To Open Next" in text
        if index == 0:
            assert "This is the start of the official walkthrough" in text
        if index < len(steps) - 1:
            next_title = steps[index + 1].title
            assert next_title in text
        else:
            assert "This notebook closes the official walkthrough" in text


def test_start_here_does_not_contain_stale_branching_advice():
    text = _notebook_text(project_root() / "notebooks" / "START_HERE.ipynb")

    assert "Read the rest of this notebook, then open `PROFESSIONAL_PATH.ipynb`." not in text
    assert "Open `PROFESSIONAL_PATH.ipynb` next." not in text
    assert "`00_circuit_literacy.ipynb`" not in text
    assert "first-pass learner journey" not in text
    assert "optional side reference" not in text
    assert "COURSE_BLUEPRINT.ipynb" in text


def test_mainline_route_text_is_single_pass_and_non_branching():
    notebook_paths = [
        project_root() / "notebooks" / "START_HERE.ipynb",
        project_root() / "notebooks" / "COURSE_BLUEPRINT.ipynb",
        project_root() / "notebooks" / "COURSE_COMPLETE.ipynb",
    ]
    banned_fragments = [
        "PROFESSIONAL_PATH.ipynb",
        "first-pass",
        "optional side reference",
        "Only then return to the later single-notebook materials as transition content",
        "If this notebook still feels unstable, repeat it before you move on.",
    ]

    for path in notebook_paths:
        text = _notebook_text(path)
        for fragment in banned_fragments:
            assert fragment not in text

    course_complete_text = _notebook_text(project_root() / "notebooks" / "COURSE_COMPLETE.ipynb")
    assert "This is the end of the mandatory walkthrough." in course_complete_text


def test_notebooks_use_explicit_cell_labels_and_difficulty_scheme():
    sample_paths = [
        project_root() / "notebooks" / "START_HERE.ipynb",
        project_root()
        / "notebooks"
        / "foundations"
        / "module_01_principles_and_circuit_literacy"
        / "lecture.ipynb",
        project_root()
        / "notebooks"
        / "foundations"
        / "module_01_principles_and_circuit_literacy"
        / "lab.ipynb",
    ]
    for path in sample_paths:
        text = _notebook_text(path)
        assert "MANDATORY READING" in text or "META READING" in text
        assert "Difficulty 1/10" in text or "Difficulty 2/10" in text or "Difficulty 3/10" in text

    lecture_text = _notebook_text(
        project_root()
        / "notebooks"
        / "foundations"
        / "module_01_principles_and_circuit_literacy"
        / "lecture.ipynb"
    )
    assert "MANDATORY TEST" in lecture_text
    assert "MANDATORY EXERCISE" in lecture_text
    assert "FACULTATIVE READING" in lecture_text
    assert "FACULTATIVE TEST" in lecture_text
    assert "FACULTATIVE EXERCISE" in lecture_text