"""Check that tools/serve.py splits a CGI response at the right place.

A CGI response ends its header block at the first blank line. cgit writes its
own headers with bare LF endings, so a body carrying a CRLF blank line, which
any commit message written on DOS does, must not be mistaken for that end.
Getting it wrong takes the document head into the header block, and the page
that reaches the browser then has no stylesheet and no chrome. Run with the
repository root and the name of one case.
"""

import importlib.util
import sys

# Loading serve.py would otherwise leave a __pycache__ directory behind in
# tools/, compiled bytecode the repository has no use for.
sys.dont_write_bytecode = True


def load_serve(root):
    path = root + "/tools/serve.py"
    spec = importlib.util.spec_from_file_location("serve", path)
    module = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(module)
    return module


# Each case names the raw output, then the status, headers and body it should
# split into.
CASES = {
    "crlf-in-body": (
        b"Content-Type: text/html\n\n<!DOCTYPE html>\nmsg\r\n\r\ntail",
        200,
        [("Content-Type", "text/html")],
        b"<!DOCTYPE html>\nmsg\r\n\r\ntail",
    ),
    "lf-in-body": (
        b"Content-Type: text/plain\r\nX: y\r\n\r\nline\n\nline2",
        200,
        [("Content-Type", "text/plain"), ("X", "y")],
        b"line\n\nline2",
    ),
    "status": (
        b"Status: 404 Not Found\nContent-Type: text/html\n\nnope",
        404,
        [("Content-Type", "text/html")],
        b"nope",
    ),
    "empty-body": (
        b"Status: 302 Found\nLocation: /x\n\n",
        302,
        [("Location", "/x")],
        b"",
    ),
    "no-blank-line": (
        b"Content-Type: text/html\n",
        200,
        [("Content-Type", "text/html")],
        b"",
    ),
}


def main():
    root, name = sys.argv[1:]
    raw, status, headers, body = CASES[name]
    got = load_serve(root).split_cgi_output(raw)
    if (got.status, got.headers, got.body) == (status, headers, body):
        return 0
    sys.stderr.write(
        "expected %r\ngot      %r\n"
        % ((status, headers, body), (got.status, got.headers, got.body))
    )
    return 1


sys.exit(main())