import matplotlib.pyplot as plt
import numpy as np

# -----------------------------
# Data
# -----------------------------
batch_sizes = [32, 64, 128]
time_kernels = [11.9, 12.6, 16.6]
time_no_kernels = [58.2, 113.5, 224.0]

x = np.arange(len(batch_sizes))
width = 0.35

# -----------------------------
# Plot
# -----------------------------
plt.figure(figsize=(10, 6))

bars1 = plt.bar(
    x - width / 2,
    time_kernels,
    width,
    label="Use kernels",
    color="#4C72B0"
)

bars2 = plt.bar(
    x + width / 2,
    time_no_kernels,
    width,
    label="No kernels",
    color="#DD8452"
)

# -----------------------------
# Labels & title
# -----------------------------
plt.title(
    "Generation Time Comparison for openai/gpt-oss-20b\n(256 tokens generated)",
    fontsize=14,
    weight="bold"
)
plt.xlabel("Batch size", fontsize=12)
plt.ylabel("Time (seconds)", fontsize=12)

plt.xticks(x, batch_sizes)
plt.legend(fontsize=11)

# -----------------------------
# Grid styling
# -----------------------------
plt.grid(
    axis="y",
    linestyle="--",
    linewidth=0.8,
    alpha=0.6
)

# -----------------------------
# Annotate bars
# -----------------------------
def annotate_bars(bars):
    for bar in bars:
        height = bar.get_height()
        plt.annotate(
            f"{height:.1f}s",
            xy=(bar.get_x() + bar.get_width() / 2, height),
            xytext=(0, 3),
            textcoords="offset points",
            ha="center",
            va="bottom",
            fontsize=10
        )

annotate_bars(bars1)
annotate_bars(bars2)

# -----------------------------
# Layout
# -----------------------------
plt.tight_layout()
plt.savefig("kernels.png")