import urllib.request
from pathlib import Path

import nox


BUILD_DIR = Path("./.build")


def clone_or_pull(session, *, target_dir, url, ref):
    # Clone or update sunpy
    target_dir.mkdir(exist_ok=True, parents=True)
    if not (target_dir / ".git").exists():
        session.run("git", "clone", "--branch", ref, url, target_dir, external=True)
    else:
        session.run("git", "-C", target_dir, "switch", ref, external=True)
        session.run("git", "-C", target_dir, "pull", "origin", ref, external=True)


def doc2dash(session, docs_dir, *, name, icon=None, online_url):
    args = [
        "--name", name,
        "--destination", ".",
        "--force",
        "--verbose",
        "--enable-js",
        "--online-redirect-url", online_url,
    ]
    if icon is not None:
        args += ["--icon", icon]

    session.run(
        "doc2dash",
        *args,
        docs_dir,
    )


@nox.session(python=["3.10"], reuse_venv=True)
def sunpy(session):
    """
    Build the sunpy docs.
    """
    sunpy_dir = BUILD_DIR / "sunpy"
    clone_or_pull(
        session,
        target_dir=sunpy_dir,
        url="git@github.com:sunpy/sunpy.git",
        ref="main",
    )

    # Install packages
    session.install("doc2dash")
    session.install("-e", f"{sunpy_dir}[docs]")

    docs = sunpy_dir / "docs"
    docs_output = docs / "_build" / "html"
    session.run(
        "sphinx-build",
        "-j", "auto",
        "--color",
        "-W",
        "--keep-going",
        "-D", "plot_gallery=0",
        "-b", "html",
        "-d", docs / "_build" / ".doctrees",
        docs,
        docs_output,
    )

    doc2dash(
        session,
        docs_output,
        name="sunpy",
        icon=docs_output / "_static" / "img" / "sunpy_icon_128x128.png",
        online_url="https://docs.sunpy.org/en/latest",
    )


@nox.session(reuse_venv=True)
def astropy(session):
    """
    Build the astropy docs.
    """
    astropy_dir = BUILD_DIR / "astropy"
    clone_or_pull(
        session,
        target_dir=astropy_dir,
        url="git@github.com:astropy/astropy.git",
        ref="main"
    )

    # Install packages
    session.install("doc2dash")
    session.install("-e", f"{astropy_dir}[docs]")

    docs = astropy_dir / "docs"
    docs_output = docs / "_build" / "html"
    session.run(
        "sphinx-build",
        "-j", "auto",
        "--color",
        "-W",
        "--keep-going",
        "-b", "html",
        "-d", docs / "_build" / ".doctrees",
        docs,
        docs_output,
    )

    with open(docs / "astropy_logo.png", "wb") as fobj:
        data = urllib.request.urlopen(
            "https://raw.githubusercontent.com/astropy/astropy-logo/main/generated/astropy_logo_notext.png"
        )
        fobj.write(data.read())


    doc2dash(
        session,
        docs_output,
        name="astropy",
        icon=docs / "astropy_logo.png",
        online_url="https://docs.astropy.org/en/latest",
    )


@nox.session(reuse_venv=True)
def parfive(session):
    """
    Build the parfive docs.
    """
    parfive_dir = BUILD_DIR / "parfive"
    clone_or_pull(
        session,
        target_dir=parfive_dir,
        url="git@github.com:Cadair/parfive.git",
        ref="main"
    )

    # Install packages
    session.install("doc2dash")
    session.install("-e", f"{parfive_dir}[docs]")

    docs = parfive_dir / "docs"
    docs_output = docs / "_build" / "html"
    session.run(
        "sphinx-build",
        "-j", "auto",
        "--color",
        "-W",
        "--keep-going",
        "-b", "html",
        "-d", docs / "_build" / ".doctrees",
        docs,
        docs_output,
    )

    doc2dash(
        session,
        docs_output,
        name="parfive",
        online_url="https://parfive.readthedocs.io/en/latest/",
    )