# This file is part of cloud-init. See LICENSE file for license information.

from . import eni
from . import RendererNotFoundError
from . import sysconfig

NAME_TO_RENDERER = {
    "eni": eni,
    "sysconfig": sysconfig,
}

DEFAULT_PRIORITY = ["eni", "sysconfig"]


def search(priority=None, target=None, first=False):
    if priority is None:
        priority = DEFAULT_PRIORITY

    available = NAME_TO_RENDERER

    unknown = [i for i in priority if i not in available]
    if unknown:
        raise ValueError(
            "Unknown renderers provided in priority list: %s" % unknown)

    found = []
    for name in priority:
        render_mod = available[name]
        if render_mod.available(target):
            cur = (name, render_mod.Renderer)
            if first:
                return cur
            found.append(cur)

    return found


def select(priority=None, target=None):
    found = search(priority, target=target, first=True)
    if not found:
        if priority is None:
            priority = DEFAULT_PRIORITY
        tmsg = ""
        if target and target != "/":
            tmsg = " in target=%s" % target
        raise RendererNotFoundError(
            "No available network renderers found%s. Searched "
            "through list: %s" % (tmsg, priority))
    return found

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