# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
# Copyright 2022 The HuggingFace Team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import random
import unittest

import numpy as np
import paddle
from parameterized import parameterized_class

from paddlenlp.transformers import (
    CODEGEN_PRETRAINED_MODEL_ARCHIVE_LIST,
    AutoTokenizer,
    CodeGenConfig,
    CodeGenForCausalLM,
    CodeGenModel,
)

from ...testing_utils import slow
from ..test_generation_utils import GenerationTesterMixin
from ..test_modeling_common import (
    ModelTesterMixin,
    floats_tensor,
    ids_tensor,
    random_attention_mask,
)


class CodeGenModelTester:
    test_model_name_list = False

    def __init__(
        self,
        parent,
        batch_size=14,
        seq_length=7,
        is_training=True,
        use_input_mask=True,
        use_labels=True,
        use_mc_token_ids=True,
        vocab_size=256,
        hidden_size=32,
        rotary_dim=4,
        num_hidden_layers=5,
        num_attention_heads=4,
        hidden_act="gelu",
        hidden_dropout_prob=0.0,
        attention_probs_dropout_prob=0.0,
        max_position_embeddings=512,
        type_vocab_size=16,
        type_sequence_label_size=2,
        initializer_range=0.02,
        num_labels=3,
        num_choices=4,
    ):
        self.parent = parent
        self.batch_size = batch_size
        self.seq_length = seq_length
        self.is_training = is_training
        self.use_input_mask = use_input_mask
        self.use_labels = use_labels
        self.use_mc_token_ids = use_mc_token_ids
        self.vocab_size = vocab_size
        self.hidden_size = hidden_size
        self.rotary_dim = rotary_dim
        self.num_hidden_layers = num_hidden_layers
        self.num_attention_heads = num_attention_heads
        self.hidden_act = hidden_act
        self.hidden_dropout_prob = hidden_dropout_prob
        self.attention_probs_dropout_prob = attention_probs_dropout_prob
        self.max_position_embeddings = max_position_embeddings
        self.type_vocab_size = type_vocab_size
        self.type_sequence_label_size = type_sequence_label_size
        self.initializer_range = initializer_range
        self.num_labels = num_labels
        self.num_choices = num_choices
        self.scope = None
        self.bos_token_id = vocab_size - 1
        self.eos_token_id = vocab_size - 1
        self.pad_token_id = vocab_size - 1

        paddle.seed(128)
        np.random.seed(128)
        random.seed(128)

    def prepare_config_and_inputs(self):
        input_ids = ids_tensor([self.batch_size, self.seq_length], self.vocab_size, dtype="int64")

        input_mask = None
        if self.use_input_mask:
            input_mask = random_attention_mask([self.batch_size, self.seq_length], dtype="int64")

        mc_token_ids = None
        if self.use_mc_token_ids:
            mc_token_ids = ids_tensor([self.batch_size, self.num_choices], self.seq_length, dtype="int64")

        sequence_labels = None
        token_labels = None
        choice_labels = None
        if self.use_labels:
            sequence_labels = ids_tensor([self.batch_size], self.type_sequence_label_size, dtype="int64")
            token_labels = ids_tensor([self.batch_size, self.seq_length], self.num_labels, dtype="int64")
            choice_labels = ids_tensor([self.batch_size], self.num_choices, dtype="int64")

        config = self.get_config()

        return (
            config,
            input_ids,
            input_mask,
            mc_token_ids,
            sequence_labels,
            token_labels,
            choice_labels,
        )

    def get_config(self):
        return CodeGenConfig(
            vocab_size=self.vocab_size,
            n_embd=self.hidden_size,
            n_layer=self.num_hidden_layers,
            n_head=self.num_attention_heads,
            activation_function=self.hidden_act,
            resid_pdrop=self.hidden_dropout_prob,
            attn_pdrop=self.attention_probs_dropout_prob,
            n_positions=self.max_position_embeddings,
            n_ctx=self.max_position_embeddings,
            initializer_range=self.initializer_range,
            bos_token_id=self.bos_token_id,
            eos_token_id=self.eos_token_id,
            pad_token_id=self.pad_token_id,
            rotary_dim=self.rotary_dim,
        )

    def prepare_config_and_inputs_for_decoder(self):
        (
            config,
            input_ids,
            input_mask,
            mc_token_ids,
            sequence_labels,
            token_labels,
            choice_labels,
        ) = self.prepare_config_and_inputs()

        encoder_hidden_states = floats_tensor([self.batch_size, self.seq_length, self.hidden_size])
        encoder_attention_mask = ids_tensor([self.batch_size, self.seq_length], vocab_size=2, dtype="int64")

        return (
            config,
            input_ids,
            input_mask,
            sequence_labels,
            token_labels,
            choice_labels,
            encoder_hidden_states,
            encoder_attention_mask,
        )

    def create_and_check_codegen_model(self, config, input_ids, input_mask, *args):
        model = CodeGenModel(config)
        model.eval()

        result = model(input_ids, use_cache=True, return_dict=self.parent.return_dict)

        self.parent.assertEqual(result[0].shape, [self.batch_size, self.seq_length, self.hidden_size])
        self.parent.assertEqual(len(result[1]), config["n_layer"])

    def create_and_check_codegen_model_past(self, config, input_ids, input_mask, *args):
        model = CodeGenModel(config)
        model.eval()

        # first forward pass
        outputs = model(input_ids, use_cache=True, return_dict=self.parent.return_dict)
        outputs_no_past = model(input_ids, use_cache=False, return_dict=self.parent.return_dict)

        self.parent.assertTrue(len(outputs) == len(outputs_no_past) + 1)

        output, past = outputs[:2]

        # create hypothetical next token and extent to next_input_ids
        next_tokens = ids_tensor((self.batch_size, 1), config["vocab_size"], dtype="int64")

        # append to next input_ids
        next_input_ids = paddle.concat([input_ids, next_tokens], axis=-1)

        output_from_no_past = model(next_input_ids, return_dict=self.parent.return_dict)[0]
        output_from_past = model(next_tokens, cache=past, return_dict=self.parent.return_dict)[0]

        # select random slice
        random_slice_idx = ids_tensor((1,), output_from_past.shape[-1], dtype="int64").item()
        output_from_no_past_slice = output_from_no_past[:, -1, random_slice_idx].detach()
        output_from_past_slice = output_from_past[:, 0, random_slice_idx].detach()

        # test that outputs are equal for slice
        self.parent.assertTrue(paddle.allclose(output_from_past_slice, output_from_no_past_slice, atol=1e-3))

    def create_and_check_codegen_model_attention_mask_past(self, config, input_ids, input_mask, *args):
        model = CodeGenModel(config)
        model.eval()

        # create attention mask
        attn_mask = paddle.ones(input_ids.shape, dtype="int64")
        half_seq_length = self.seq_length // 2
        attn_mask[:, half_seq_length:] = 0

        # first forward pass
        output, past = model(input_ids, attention_mask=attn_mask, use_cache=True, return_dict=self.parent.return_dict)[
            :2
        ]

        # create hypothetical next token and extent to next_input_ids
        next_tokens = ids_tensor((self.batch_size, 1), config["vocab_size"], dtype="int64")

        # change a random masked slice from input_ids
        random_seq_idx_to_change = ids_tensor((1,), half_seq_length, dtype="int64").item() + 1
        random_other_next_tokens = ids_tensor((self.batch_size, 1), config["vocab_size"], dtype="int64").squeeze(-1)
        input_ids[:, -random_seq_idx_to_change] = random_other_next_tokens

        # append to next input_ids and attn_mask
        next_input_ids = paddle.concat([input_ids, next_tokens], axis=-1)
        attn_mask = paddle.concat(
            [attn_mask, paddle.ones((attn_mask.shape[0], 1), dtype="int64")],
            axis=1,
        )

        # get two different outputs
        output_from_no_past = model(next_input_ids, attention_mask=attn_mask, return_dict=self.parent.return_dict)[0]
        output_from_past = model(
            next_tokens, cache=past, attention_mask=attn_mask, return_dict=self.parent.return_dict
        )[0]

        # select random slice
        random_slice_idx = ids_tensor((1,), output_from_past.shape[-1], dtype="int64").item()
        output_from_no_past_slice = output_from_no_past[:, -1, random_slice_idx].detach()
        output_from_past_slice = output_from_past[:, 0, random_slice_idx].detach()

        # test that outputs are equal for slice
        self.parent.assertTrue(paddle.allclose(output_from_past_slice, output_from_no_past_slice, atol=1e-3))

    def create_and_check_codegen_model_past_large_inputs(self, config, input_ids, input_mask, *args):
        model = CodeGenModel(config)
        model.eval()

        # first forward pass
        outputs = model(input_ids, attention_mask=input_mask, use_cache=True, return_dict=self.parent.return_dict)

        output, past = outputs[:2]

        # create hypothetical next token and extent to next_input_ids
        next_tokens = ids_tensor((self.batch_size, 3), config["vocab_size"], dtype="int64")
        next_mask = ids_tensor((self.batch_size, 3), vocab_size=2, dtype="int64")

        # append to next input_ids
        next_input_ids = paddle.concat([input_ids, next_tokens], axis=-1)
        next_attention_mask = paddle.concat([input_mask, next_mask], axis=-1)

        output_from_no_past = model(
            next_input_ids, attention_mask=next_attention_mask, return_dict=self.parent.return_dict
        )[0]
        output_from_past = model(
            next_tokens, attention_mask=next_attention_mask, cache=past, return_dict=self.parent.return_dict
        )[0]
        self.parent.assertTrue(output_from_past.shape[1] == next_tokens.shape[1])

        # select random slice
        random_slice_idx = ids_tensor((1,), output_from_past.shape[-1], dtype="int64").item()
        output_from_no_past_slice = output_from_no_past[:, -3:, random_slice_idx].detach()
        output_from_past_slice = output_from_past[:, :, random_slice_idx].detach()

        # test that outputs are equal for slice
        self.parent.assertTrue(paddle.allclose(output_from_past_slice, output_from_no_past_slice, atol=1e-3))

    def create_and_check_lm_head_model(self, config, input_ids, input_mask, *args):
        model = CodeGenForCausalLM(config)

        outputs = model(
            input_ids, labels=input_ids if self.parent.use_labels else None, return_dict=self.parent.return_dict
        )
        if self.parent.use_labels:
            loss, logits = outputs[:2]
            self.parent.assertEqual(loss.shape, [1])
        else:
            logits = outputs[0]
        self.parent.assertEqual(logits.shape, [self.batch_size, self.seq_length, self.vocab_size])

    def create_and_check_forward_and_backwards(self, config, input_ids, input_mask, *args):
        model = CodeGenForCausalLM(config)

        loss, logits = model(input_ids, return_dict=self.parent.return_dict, labels=input_ids)[:2]
        self.parent.assertEqual(loss.shape, [1])
        self.parent.assertEqual(logits.shape, [self.batch_size, self.seq_length, self.vocab_size])
        loss.backward()

    def prepare_config_and_inputs_for_common(self):
        config_and_inputs = self.prepare_config_and_inputs()

        (
            config,
            input_ids,
            input_mask,
            mc_token_ids,
            sequence_labels,
            token_labels,
            choice_labels,
        ) = config_and_inputs

        inputs_dict = {"input_ids": input_ids}

        return config, inputs_dict


@parameterized_class(
    ("return_dict",),
    [
        [False, False],
        [False, True],
        [True, False],
        [True, True],
    ],
)
class CodeGenModelTest(ModelTesterMixin, GenerationTesterMixin, unittest.TestCase):
    base_model_class = CodeGenModel

    all_model_classes = (CodeGenModel, CodeGenForCausalLM)
    all_generative_model_classes = {CodeGenForCausalLM: (CodeGenModel, "transformer")}
    fx_compatible = False
    test_pruning = False
    test_missing_keys = False
    test_model_parallel = False
    test_head_masking = False
    use_test_model_name_list = False
    return_dict = False
    use_labels = False
    use_test_inputs_embeds = True

    # attention mask issue
    def _get_input_ids_and_config(self):
        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()

        input_ids = inputs_dict[self.input_name]
        attention_mask = paddle.zeros_like(input_ids, dtype=paddle.float32)

        max_batch_size = 2
        sequence_length = input_ids.shape[-1] // 2
        input_ids = input_ids[:max_batch_size, :sequence_length]
        attention_mask = attention_mask[:max_batch_size, :sequence_length].unsqueeze([1, 2])

        # generate max 3 tokens
        max_length = 3

        if config.get("eos_token_id", None) is not None and config.get("pad_token_id", None) is None:
            # hack to allow generate for models such as GPT2 as is done in `generate()`
            config["pad_token_id"] = config["eos_token_id"]

        return config, input_ids, attention_mask, max_length

    # special case for DoubleHeads model
    def _prepare_for_class(self, inputs_dict, model_class):
        inputs_dict = super()._prepare_for_class(inputs_dict, model_class)
        return inputs_dict

    def setUp(self):
        self.model_tester = CodeGenModelTester(self)

    def test_codegen_model(self):
        config_and_inputs = self.model_tester.prepare_config_and_inputs()
        self.model_tester.create_and_check_codegen_model(*config_and_inputs)

    def test_codegen_model_past(self):
        config_and_inputs = self.model_tester.prepare_config_and_inputs()
        self.model_tester.create_and_check_codegen_model_past(*config_and_inputs)

    def test_codegen_model_att_mask_past(self):
        config_and_inputs = self.model_tester.prepare_config_and_inputs()
        self.model_tester.create_and_check_codegen_model_attention_mask_past(*config_and_inputs)

    def test_codegen_model_past_large_inputs(self):
        config_and_inputs = self.model_tester.prepare_config_and_inputs()
        self.model_tester.create_and_check_codegen_model_past_large_inputs(*config_and_inputs)

    def test_codegen_lm_head_model(self):
        config_and_inputs = self.model_tester.prepare_config_and_inputs()
        self.model_tester.create_and_check_lm_head_model(*config_and_inputs)

    @slow
    def test_batch_generation(self):
        tokenizer = AutoTokenizer.from_pretrained("Salesforce/codegen-350M-mono")
        model = CodeGenForCausalLM.from_pretrained("Salesforce/codegen-350M-mono")
        model.eval()

        tokenizer.padding_side = "left"

        # Define PAD Token = EOS Token = 50256
        tokenizer.pad_token = tokenizer.eos_token
        model.transformer.config["pad_token_id"] = model.transformer.config["eos_token_id"]

        # use different length sentences to test batching
        sentences = ["def hellow_world():", "def greet(name):"]

        inputs = tokenizer(sentences, return_tensors="pd", padding=True, return_attention_mask=True)
        input_ids = inputs["input_ids"]

        outputs, _ = model.generate(
            input_ids=input_ids,
            attention_mask=inputs["attention_mask"],
        )

        inputs_non_padded = tokenizer(sentences[0], return_tensors="pd")["input_ids"]
        output_non_padded, _ = model.generate(input_ids=inputs_non_padded)

        inputs_padded = tokenizer(sentences[1], return_tensors="pd")["input_ids"]
        output_padded, _ = model.generate(input_ids=inputs_padded)

        # batch_out_sentence = tokenizer.batch_decode(outputs, skip_special_tokens=True)

        non_padded_sentence = tokenizer.decode(output_non_padded[0], skip_special_tokens=True)
        padded_sentence = tokenizer.decode(output_padded[0], skip_special_tokens=True)

        expected_output_sentence = [
            '\n      print("Hello World")\n\nhellow_world()\n\n#',
            '\n      print(f"Hello {name}")\n\ngreet("Rolf")\n',
        ]
        # self.assertEqual(str(expected_output_sentence), str(batch_out_sentence))
        self.assertEqual(str(expected_output_sentence), str([non_padded_sentence, padded_sentence]))

    @slow
    def test_model_from_pretrained(self):
        for model_name in CODEGEN_PRETRAINED_MODEL_ARCHIVE_LIST[:1]:
            model = CodeGenModel.from_pretrained(model_name)
            self.assertIsNotNone(model)

    @unittest.skip("Not implemented")
    def test_model_name_list(self):
        pass

    @slow
    def test_auto_tokenizer(self):
        for model_name in CODEGEN_PRETRAINED_MODEL_ARCHIVE_LIST:
            AutoTokenizer.from_pretrained(model_name)  # assign a tokenizer but never use


class CodeGenModelLanguageGenerationTest(unittest.TestCase):
    @slow
    def test_lm_generate_codegen(self):
        tokenizer = AutoTokenizer.from_pretrained("Salesforce/codegen-350M-mono")
        model = CodeGenForCausalLM.from_pretrained("Salesforce/codegen-350M-mono")
        model.eval()

        inputs = tokenizer(
            "def hello_world():", return_tensors="pd", return_attention_mask=True, return_token_type_ids=False
        )
        expected_output = '\n      print("Hello World")\n\nhello_world()\n\n#'

        output_ids, _ = model.generate(**inputs, decode_strategy="sampling", top_k=1)
        output_str = tokenizer.batch_decode(output_ids)[0]

        self.assertEqual(output_str, expected_output)

    @slow
    def test_codegen_sample(self):
        tokenizer = AutoTokenizer.from_pretrained("Salesforce/codegen-350M-mono")
        model = CodeGenForCausalLM.from_pretrained("Salesforce/codegen-350M-mono")
        model.eval()

        tokenized = tokenizer(
            "def hello_world():", return_tensors="pd", return_token_type_ids=True, return_attention_mask=True
        )
        input_ids = tokenized["input_ids"]
        output_ids, _ = model.generate(input_ids, decode_strategy="sampling", top_k=1)
        output_str = tokenizer.decode(output_ids[0], skip_special_tokens=True)

        token_type_ids = tokenized.token_type_ids
        output_seq, _ = model.generate(
            input_ids=input_ids, decode_strategy="sampling", top_k=1, num_return_sequences=5
        )
        output_seq_tt, _ = model.generate(
            input_ids=input_ids,
            token_type_ids=token_type_ids,
            decode_strategy="sampling",
            top_k=1,
            num_return_sequences=5,
        )
        output_seq_strs = tokenizer.batch_decode(output_seq, skip_special_tokens=True)
        output_seq_tt_strs = tokenizer.batch_decode(output_seq_tt, skip_special_tokens=True)

        EXPECTED_OUTPUT_STR = '\n      print("Hello World")\n\nhello_world()\n\n#'

        self.assertEqual(output_str, EXPECTED_OUTPUT_STR)
        self.assertTrue(
            all([output_seq_strs[idx] != output_seq_tt_strs[idx] for idx in range(len(output_seq_tt_strs))])
        )  # token_type_ids should change output
