# Copyright (C) 2019 Analog Devices, Inc.
#
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# are permitted provided that the following conditions are met:
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#       contributors may be used to endorse or promote products derived
#       from this software without specific prior written permission.
#     - The use of this software may or may not infringe the patent rights
#       of one or more patent holders.  This license does not release you
#       from the requirement that you obtain separate licenses from these
#       patent holders to use this software.
#     - Use of the software either in source or binary form, must be run
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# INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A
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# THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import iio


class context_manager(object):
    _uri_auto = "ip:analog"
    _ctx = None

    def __init__(self, uri="", _device_name=""):
        if self._ctx:
            return
        self.uri = uri
        try:
            if self.uri == "":
                # Try USB contexts first
                if _device_name != "":
                    contexts = iio.scan_contexts()
                    for c in contexts:
                        if _device_name in contexts[c]:
                            self._ctx = iio.Context(c)
                            break
                # Try auto discover
                if not self._ctx and self._uri_auto != "":
                    self._ctx = iio.Context(self._uri_auto)
                if not self._ctx:
                    raise Exception("No device found")
            else:
                self._ctx = iio.Context(self.uri)
        except BaseException:
            raise Exception("No device found")
