# Copyright The Lightning team.
#
# 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 argparse

import matplotlib.pyplot as plt
import torch


def pesq_example() -> tuple:
    """Plot PESQ audio example."""
    from torchmetrics.audio.pesq import PerceptualEvaluationSpeechQuality

    p = lambda: torch.randn(8000)
    t = lambda: torch.randn(8000)

    # plot single value
    metric = PerceptualEvaluationSpeechQuality(8000, "nb")
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = PerceptualEvaluationSpeechQuality(16000, "wb")
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def pit_example() -> tuple:
    """Plot PIT audio example."""
    from torchmetrics.audio.pit import PermutationInvariantTraining
    from torchmetrics.functional import scale_invariant_signal_noise_ratio

    p = lambda: torch.randn(3, 2, 5)
    t = lambda: torch.randn(3, 2, 5)

    # plot single value
    metric = PermutationInvariantTraining(scale_invariant_signal_noise_ratio, "max")
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = PermutationInvariantTraining(scale_invariant_signal_noise_ratio, "max")
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def sdr_example() -> tuple:
    """Plot SDR audio example."""
    from torchmetrics.audio.sdr import SignalDistortionRatio

    p = lambda: torch.randn(8000)
    t = lambda: torch.randn(8000)

    # plot single value
    metric = SignalDistortionRatio()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = SignalDistortionRatio()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def si_sdr_example() -> tuple:
    """Plot SI-SDR audio example."""
    from torchmetrics.audio.sdr import ScaleInvariantSignalDistortionRatio

    p = lambda: torch.randn(5)
    t = lambda: torch.randn(5)

    # plot single value
    metric = ScaleInvariantSignalDistortionRatio()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = ScaleInvariantSignalDistortionRatio()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def snr_example() -> tuple:
    """Plot SNR audio example."""
    from torchmetrics.audio.snr import SignalNoiseRatio

    p = lambda: torch.randn(4)
    t = lambda: torch.randn(4)

    # plot single value
    metric = SignalNoiseRatio()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = SignalNoiseRatio()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def si_snr_example() -> tuple:
    """Plot SI-SNR example."""
    from torchmetrics.audio.snr import ScaleInvariantSignalNoiseRatio

    p = lambda: torch.randn(4)
    t = lambda: torch.randn(4)

    # plot single value
    metric = ScaleInvariantSignalNoiseRatio()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = ScaleInvariantSignalNoiseRatio()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def stoi_example() -> tuple:
    """Plot STOI example."""
    from torchmetrics.audio.stoi import ShortTimeObjectiveIntelligibility

    p = lambda: torch.randn(8000)
    t = lambda: torch.randn(8000)

    # plot single value
    metric = ShortTimeObjectiveIntelligibility(8000, False)
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = ShortTimeObjectiveIntelligibility(8000, False)
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def accuracy_example() -> tuple:
    """Plot Accuracy example."""
    from torchmetrics.classification import MulticlassAccuracy

    p = lambda: torch.randn(20, 5)
    t = lambda: torch.randint(5, (20,))

    # plot single value
    metric = MulticlassAccuracy(num_classes=5)
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot a value per class
    metric = MulticlassAccuracy(num_classes=5, average=None)
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot two values as a series
    metric = MulticlassAccuracy(num_classes=5)
    val1 = metric(p(), t())
    val2 = metric(p(), t())
    fig, ax = metric.plot([val1, val2])

    # plot a series of values per class
    metric = MulticlassAccuracy(num_classes=5, average=None)
    val1 = metric(p(), t())
    val2 = metric(p(), t())
    fig, ax = metric.plot([val1, val2])
    return fig, ax


def mean_squared_error_example() -> tuple:
    """Plot mean squared error example."""
    from torchmetrics.regression import MeanSquaredError

    p = lambda: torch.randn(20)
    t = lambda: torch.randn(20)

    # single val
    metric = MeanSquaredError()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # multiple values
    metric = MeanSquaredError()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)
    return fig, ax


def confusion_matrix_example() -> tuple:
    """Plot confusion matrix example."""
    from torchmetrics.classification import MulticlassConfusionMatrix

    p = lambda: torch.randn(20, 5)
    t = lambda: torch.randint(5, (20,))

    # plot single value
    metric = MulticlassConfusionMatrix(num_classes=5)
    metric.update(p(), t())
    fig, ax = metric.plot()
    return fig, ax


def spectral_distortion_index_example() -> tuple:
    """Plot spectral distortion index example example."""
    from torchmetrics.image.d_lambda import SpectralDistortionIndex

    p = lambda: torch.rand([16, 3, 16, 16])
    t = lambda: torch.rand([16, 3, 16, 16])

    # plot single value
    metric = SpectralDistortionIndex()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = SpectralDistortionIndex()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def error_relative_global_dimensionless_synthesis() -> tuple:
    """Plot error relative global dimensionless synthesis example."""
    from torchmetrics.image.ergas import ErrorRelativeGlobalDimensionlessSynthesis

    p = lambda: torch.rand([16, 1, 16, 16], generator=torch.manual_seed(42))
    t = lambda: torch.rand([16, 1, 16, 16], generator=torch.manual_seed(42))

    # plot single value
    metric = ErrorRelativeGlobalDimensionlessSynthesis()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = ErrorRelativeGlobalDimensionlessSynthesis()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def peak_signal_noise_ratio() -> tuple:
    """Plot peak signal noise ratio example."""
    from torchmetrics.image.psnr import PeakSignalNoiseRatio

    p = lambda: torch.tensor([[0.0, 1.0], [2.0, 3.0]])
    t = lambda: torch.tensor([[3.0, 2.0], [1.0, 0.0]])

    # plot single value
    metric = PeakSignalNoiseRatio()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = PeakSignalNoiseRatio()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def spectral_angle_mapper() -> tuple:
    """Plot spectral angle mapper example."""
    from torchmetrics.image.sam import SpectralAngleMapper

    p = lambda: torch.rand([16, 3, 16, 16], generator=torch.manual_seed(42))
    t = lambda: torch.rand([16, 3, 16, 16], generator=torch.manual_seed(123))

    # plot single value
    metric = SpectralAngleMapper()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = SpectralAngleMapper()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def structural_similarity_index_measure() -> tuple:
    """Plot structural similarity index measure example."""
    from torchmetrics.image.ssim import StructuralSimilarityIndexMeasure

    p = lambda: torch.rand([3, 3, 256, 256], generator=torch.manual_seed(42))
    t = lambda: p() * 0.75

    # plot single value
    metric = StructuralSimilarityIndexMeasure()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = StructuralSimilarityIndexMeasure()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def multiscale_structural_similarity_index_measure() -> tuple:
    """Plot multiscale structural similarity index measure example."""
    from torchmetrics.image.ssim import MultiScaleStructuralSimilarityIndexMeasure

    p = lambda: torch.rand([3, 3, 256, 256], generator=torch.manual_seed(42))
    t = lambda: p() * 0.75

    # plot single value
    metric = MultiScaleStructuralSimilarityIndexMeasure()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = MultiScaleStructuralSimilarityIndexMeasure()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def universal_image_quality_index() -> tuple:
    """Plot universal image quality index example."""
    from torchmetrics.image.uqi import UniversalImageQualityIndex

    p = lambda: torch.rand([16, 1, 16, 16])
    t = lambda: p() * 0.75

    # plot single value
    metric = UniversalImageQualityIndex()
    metric.update(p(), t())
    fig, ax = metric.plot()

    # plot multiple values
    metric = UniversalImageQualityIndex()
    vals = [metric(p(), t()) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def mean_average_precision() -> tuple:
    """Plot MAP metric."""
    from torchmetrics.detection.mean_ap import MeanAveragePrecision

    preds = lambda: [
        {
            "boxes": torch.tensor([[258.0, 41.0, 606.0, 285.0]]) + torch.randint(10, (1, 4)),
            "scores": torch.tensor([0.536]) + 0.1 * torch.rand(1),
            "labels": torch.tensor([0]),
        }
    ]
    target = [
        {
            "boxes": torch.tensor([[214.0, 41.0, 562.0, 285.0]]),
            "labels": torch.tensor([0]),
        }
    ]

    # plot single value
    metric = MeanAveragePrecision()
    metric.update(preds(), target)
    fig, ax = metric.plot()

    # plot multiple values
    metric = MeanAveragePrecision()
    vals = [metric(preds(), target) for _ in range(10)]
    fig, ax = metric.plot(vals)

    return fig, ax


def roc_example() -> tuple:
    """Plot roc metric."""
    from torchmetrics.classification import BinaryROC, MulticlassROC, MultilabelROC

    p = lambda: torch.rand(20)
    t = lambda: torch.randint(2, (20,))

    metric = BinaryROC()
    metric.update(p(), t())
    fig, ax = metric.plot()

    p = lambda: torch.randn(200, 5)
    t = lambda: torch.randint(5, (200,))

    metric = MulticlassROC(5)
    metric.update(p(), t())
    fig, ax = metric.plot()

    p = lambda: torch.rand(20, 2)
    t = lambda: torch.randint(2, (20, 2))

    metric = MultilabelROC(2)
    metric.update(p(), t())

    return fig, ax


if __name__ == "__main__":
    metrics_func = {
        "accuracy": accuracy_example,
        "roc": roc_example,
        "pesq": pesq_example,
        "pit": pit_example,
        "sdr": sdr_example,
        "si-sdr": si_sdr_example,
        "snr": snr_example,
        "si-snr": si_snr_example,
        "stoi": stoi_example,
        "mean_squared_error": mean_squared_error_example,
        "mean_average_precision": mean_average_precision,
        "confusion_matrix": confusion_matrix_example,
        "spectral_distortion_index": spectral_distortion_index_example,
        "error_relative_global_dimensionless_synthesis": error_relative_global_dimensionless_synthesis,
        "peak_signal_noise_ratio": peak_signal_noise_ratio,
        "spectral_angle_mapper": spectral_angle_mapper,
        "structural_similarity_index_measure": structural_similarity_index_measure,
        "multiscale_structural_similarity_index_measure": multiscale_structural_similarity_index_measure,
        "universal_image_quality_index": universal_image_quality_index,
    }

    parser = argparse.ArgumentParser(description="Example script for plotting metrics.")
    parser.add_argument("metric", type=str, nargs="?", choices=list(metrics_func.keys()), default="accuracy")
    args = parser.parse_args()

    fig, ax = metrics_func[args.metric]()

    plt.show()
