# File: vehicle/komatsu.py
# Copyright (C) 2026 Erick Ahmed
# SPDX-License-Identifier: AGPL-3.0-or-later

"""Komatsu-specific CAN frame decoder rules and custom plot definitions."""

from copy import deepcopy
from dataclasses import dataclass
from typing import Callable, Dict

import pandas as pd
import plotly.express as px

from vehicle.base import (
    FrameDef,
    SignalDef,
    decode_dataframe as _decode_dataframe,
    normalize_id,
    plot_signal,
)


@dataclass
class CustomPlotDef:
    """A non-signal entry in a FrameDef that carries its own plotting function."""

    name: str
    plot_func: Callable

load_state_sig = SignalDef(
    name="Engine Load State",
    bit_start=24,
    bit_length=8,
    factor=1,
    offset=0.0,
    is_signed=False,
    byte_order="big",
    unit="",
)
load_state_sig.skip_plot = True

DECODER_RULES: Dict[str, FrameDef] = {
    normalize_id("0x011F"): FrameDef(
        can_id="0x011F",
        description="ECM",
        color="#e41a1c",
        signals=[
            SignalDef(
                name="Engine",
                bit_start=0,
                bit_length=16,
                factor=0.125,
                offset=0.0,
                is_signed=False,
                byte_order="big",
                unit="RPM",
            ),
            SignalDef(
                name="Engine Load",
                bit_start=16,
                bit_length=16,
                factor=0.05,
                offset=0,
                is_signed=False,
                byte_order="little",
                unit="%",
            ),
        ],
    ),
    normalize_id("0x0CFF3300"): FrameDef(
        can_id="0x0CFF3300",
        description="Engine temperatures",
        color="#0080fe",
        signals=[
            SignalDef(
                name="Engine coolant temp",
                bit_start=8,
                bit_length=8,
                factor=1,
                offset=0.0,
                is_signed=False,
                byte_order="big",
                unit="℃",
            ),
            SignalDef(
                name="Engine oil temp",
                bit_start=40,
                bit_length=8,
                factor=1,
                offset=0.0,
                is_signed=False,
                byte_order="big",
                unit="℃",
            ),
            load_state_sig,
            CustomPlotDef(
                name="Engine Load",
                plot_func=lambda decoded, color: plot_load_state_pie(decoded, color),
            ),
        ],
    ),
}

LOAD_STATE_MAP = {
    0: "Boot up",
    16: "Normal load",
    32: "High load",
}

_LOAD_STATE_COLORS = {
    "Boot up": "#ff9900",
    "Normal load": "#00cc00",
    "High load": "#cc0000",
    "Unknown": "#808080",
}


def plot_load_state_pie(decoded_df, color):
    """Render a pie chart showing the distribution of engine load states."""
    if decoded_df is None or decoded_df.empty or "Engine Load State" not in decoded_df.columns:
        fig = px.pie()
        fig.update_layout(
            title=dict(
                text="Engine Load State",
                font=dict(size=14, color="#1a1a1a"),
                x=0.5, xanchor="center", pad=dict(b=10)
            ),
            height=280,
            template="plotly_white",
            annotations=[dict(text="No data", showarrow=False, x=0.5, y=0.5, font=dict(size=13, color="#888"))]
        )
        return fig

    states = pd.to_numeric(decoded_df["Engine Load State"], errors="coerce").dropna().astype(int)

    labels = states.map(LOAD_STATE_MAP).fillna("Unknown")
    counts = labels.value_counts().reset_index()
    counts.columns = ["State", "Count"]

    total = counts["Count"].sum()
    counts["Percentage"] = (counts["Count"] / total * 100).round(1)
    counts["Legend"] = counts["State"] + " (" + counts["Percentage"].astype(str) + "%)"

    fig = px.pie(
        counts,
        values="Count",
        names="Legend",
        color="State",
        color_discrete_map=_LOAD_STATE_COLORS,
    )

    fig.update_traces(
        textinfo="none",
        hoverinfo="label+percent+value",
        domain={"x": [0.05, 0.55], "y": [0.05, 0.95]},
    )
    fig.update_layout(
        title=dict(
            text="Engine Load State",
            font=dict(size=14, color="#1a1a1a"),
            x=0.5, xanchor="center", pad=dict(b=10)
        ),
        height=280,
        autosize=True,
        template="plotly_white",
        margin=dict(l=20, r=20, t=55, b=45),
        font=dict(family="Segoe UI, Arial, sans-serif", size=11, color="#2a2a2a"),
        legend=dict(x=0.6, y=0.5),
    )
    return fig

def decode_dataframe(df, can_id):
    """Decode *can_id* from *df*, filtering out non-SignalDef entries first."""
    filtered_rules: Dict[str, FrameDef] = {}
    for nid, frame in DECODER_RULES.items():
        new_frame = deepcopy(frame)
        new_frame.signals = [s for s in frame.signals if isinstance(s, SignalDef)]
        filtered_rules[nid] = new_frame

    return _decode_dataframe(df, can_id, filtered_rules)