import json
import os
import sys
from base64 import decodebytes
from unittest import TestCase

from nbformat.v4 import nbformat, nbformat_minor, nbjson
from nbformat.v4.nbjson import writes

from . import formattest
from .nbexamples import nb0

BASE_PATH = os.path.join(sys.modules["nbformat"].__path__[0], "v4")


class TestJSON(formattest.NBFormatTest, TestCase):

    nb0_ref = None
    ext = "ipynb"
    mod = nbjson

    def test_roundtrip_nosplit(self):
        """Ensure that multiline blobs are still readable"""
        # ensures that notebooks written prior to splitlines change
        # are still readable.
        s = writes(nb0, split_lines=False)
        self.assertEqual(nbjson.reads(s), nb0)

    def test_roundtrip_split(self):
        """Ensure that splitting multiline blocks is safe"""
        # This won't differ from test_roundtrip unless the default changes
        s = writes(nb0, split_lines=True)
        self.assertEqual(nbjson.reads(s), nb0)

    def test_splitlines(self):
        """Test splitlines in mime-bundles"""
        s = writes(nb0, split_lines=True)
        raw_nb = json.loads(s)

        for i, ref_cell in enumerate(nb0.cells):
            if ref_cell.source.strip() == "Cell with attachments":
                attach_ref = ref_cell["attachments"]["attachment1"]
                attach_json = raw_nb["cells"][i]["attachments"]["attachment1"]
            if ref_cell.source.strip() == "json_outputs()":
                output_ref = ref_cell["outputs"][0]["data"]
                output_json = raw_nb["cells"][i]["outputs"][0]["data"]

        for key, json_value in attach_json.items():
            if key == "text/plain":
                # text should be split
                assert json_value == attach_ref["text/plain"].splitlines(True)
            else:
                # JSON attachments
                assert json_value == attach_ref[key]

        # check that JSON outputs are left alone:
        for key, json_value in output_json.items():
            if key == "text/plain":
                # text should be split
                assert json_value == output_ref["text/plain"].splitlines(True)
            else:
                # JSON outputs should be left alone
                assert json_value == output_ref[key]

    def test_read_png(self):
        """PNG output data is b64 unicode"""
        s = writes(nb0)
        nb1 = nbjson.reads(s)
        found_png = False
        for cell in nb1.cells:
            if "outputs" not in cell:
                continue
            for output in cell.outputs:
                if "data" not in output:
                    continue
                if "image/png" in output.data:
                    found_png = True
                    pngdata = output.data["image/png"]
                    self.assertEqual(type(pngdata), str)
                    # test that it is valid b64 data
                    b64bytes = pngdata.encode("ascii")
                    raw_bytes = decodebytes(b64bytes)
        assert found_png, "never found png output"

    def test_read_jpeg(self):
        """JPEG output data is b64 unicode"""
        s = writes(nb0)
        nb1 = nbjson.reads(s)
        found_jpeg = False
        for cell in nb1.cells:
            if "outputs" not in cell:
                continue
            for output in cell.outputs:
                if "data" not in output:
                    continue
                if "image/jpeg" in output.data:
                    found_jpeg = True
                    jpegdata = output.data["image/jpeg"]
                    self.assertEqual(type(jpegdata), str)
                    # test that it is valid b64 data
                    b64bytes = jpegdata.encode("ascii")
                    raw_bytes = decodebytes(b64bytes)
        assert found_jpeg, "never found jpeg output"

    def test_latest_schema_matches(self):
        """Test to ensure all schema is locked to a known version"""
        assert nbformat == 4
        assert nbformat_minor == 5

    def test_base_version_matches_latest(self):
        """Test to ensure latest version file matches latest verison"""
        with open(os.path.join(BASE_PATH, "nbformat.v4.schema.json")) as schema_file:
            latest_schema = json.load(schema_file)
            with open(
                os.path.join(
                    BASE_PATH,
                    "nbformat.v{major}.{minor}.schema.json".format(
                        major=nbformat, minor=nbformat_minor
                    ),
                ),
            ) as schema_file:
                ver_schema = json.load(schema_file)
            assert latest_schema == ver_schema

    def test_latest_matches_nbformat(self):
        """Test to ensure that the nbformat version matches the description of the latest schema"""
        with open(os.path.join(BASE_PATH, "nbformat.v4.schema.json")) as schema_file:
            schema = json.load(schema_file)
        assert schema["description"] == "Jupyter Notebook v{major}.{minor} JSON schema.".format(
            major=nbformat, minor=nbformat_minor
        )