from __future__ import annotations

from pathlib import Path


ROOT_DIR = Path(__file__).resolve().parent
OUTPUT_PATH = ROOT_DIR / "livre.md"


def strip_yaml_front_matter(text: str) -> str:
    """
    Remove a leading YAML front-matter block:

    ---
    ...
    ---

    Only strips when the file starts with '---' on the first line.
    """
    lines = text.splitlines(keepends=True)
    if not lines:
        return text

    if lines[0].strip() != "---":
        return text

    for idx in range(1, len(lines)):
        if lines[idx].strip() == "---":
            # Strip the closing '---' line too.
            return "".join(lines[idx + 1 :])

    return text


def normalize_section(source_filename: str, raw_text: str) -> str:
    content = strip_yaml_front_matter(raw_text).lstrip("\n")

    # Chapter 2 is missing a proper heading in v0; add it deterministically.
    if source_filename == "chapitre2.md":
        if content.startswith("Introduction\n\n"):
            content = content.removeprefix("Introduction\n\n")

        content = (
            "# Chapitre 2 : Itération, finitude locale et répétition nécessaire\n\n"
            "## Introduction\n\n"
            f"{content}"
        )

    return f"{content.rstrip()}\n"


def build_sources() -> list[str]:
    sources: list[str] = []

    sources.append("introduction.md")

    for i in range(1, 17):
        sources.append(f"chapitre{i}.md")

    sources.append("fermeture.md")

    sources.append("analyse_critique_ouvrage.md")

    for i in range(17, 24):
        sources.append(f"chapitre{i}.md")

    sources.append("analyse_critique_ouvrage2.md")

    for i in range(24, 33):
        sources.append(f"chapitre{i}.md")

    sources.append("references.md")
    sources.append("plan_total_ouvrage.md")

    return sources


def main() -> None:
    sources = build_sources()

    missing = [name for name in sources if not (ROOT_DIR / name).exists()]
    if missing:
        missing_list = ", ".join(missing)
        raise FileNotFoundError(f"Missing sources in {ROOT_DIR}: {missing_list}")

    out_parts: list[str] = [
        "---\n"
        'livre: "Théorie des futurs accessibles"\n'
        "version: v0\n"
        "auteur: Nicolas Cantu\n"
        "---\n\n"
        "<!-- Compiled from v0/*.md sources. -->\n"
        "<!-- Do not edit manually: run v0/compile_livre.py -->\n\n"
    ]

    print(f"Writing {OUTPUT_PATH} from {len(sources)} sources.")

    for idx, source in enumerate(sources):
        source_path = ROOT_DIR / source
        raw = source_path.read_text(encoding="utf-8")
        content = normalize_section(source, raw)

        print(f"- {source} ({content.count(chr(10))} lines)")

        out_parts.append(f"<!-- BEGIN v0/{source} -->\n\n")
        out_parts.append(content)
        out_parts.append(f"\n<!-- END v0/{source} -->\n")

        is_last = idx == len(sources) - 1
        if not is_last:
            out_parts.append("\n---\n\n")

    OUTPUT_PATH.write_text("".join(out_parts), encoding="utf-8")


if __name__ == "__main__":
    main()