import json
from pathlib import Path

import pandas as pd
import plotly.express as px
import plotly.io as pio

input_path = Path('triangulated_lamps.csv')
output_dir = Path('output')
output_dir.mkdir(exist_ok=True)
chart_path = output_dir / 'lamp_map_2d.png'
meta_path = output_dir / 'lamp_map_2d.png.meta.json'
csv_out = output_dir / 'lamp_map_2d_points.csv'

if not input_path.exists():
    raise FileNotFoundError(f'Không tìm thấy file input: {input_path.resolve()}')

df = pd.read_csv(input_path)

required_cols = ['lamp_id', 'x_m_local', 'y_m_local', 'mean_ray_distance_m']
for c in required_cols:
    if c not in df.columns:
        raise ValueError(f'Thiếu cột bắt buộc: {c}')

df['lamp_id'] = df['lamp_id'].astype(str)
df['x_m_local'] = pd.to_numeric(df['x_m_local'], errors='coerce')
df['y_m_local'] = pd.to_numeric(df['y_m_local'], errors='coerce')
df['mean_ray_distance_m'] = pd.to_numeric(df['mean_ray_distance_m'], errors='coerce')
df = df.dropna(subset=['x_m_local', 'y_m_local']).copy()
df = df.sort_values('lamp_id', key=lambda s: s.astype(int))
df['label'] = 'Lamp ' + df['lamp_id']
df['ray_err_m'] = df['mean_ray_distance_m'].round(2)

df.to_csv(csv_out, index=False, encoding='utf-8-sig')

fig = px.scatter(
    df,
    x='x_m_local',
    y='y_m_local',
    color='mean_ray_distance_m',
    text='lamp_id',
    hover_name='label',
    hover_data={
        'x_m_local': ':.2f',
        'y_m_local': ':.2f',
        'mean_ray_distance_m': ':.2f'
    },
    title='2D Lamp Map (local XY)<br><span style="font-size: 18px; font-weight: normal;">Source: triangulated_lamps.csv | Color representation mean ray distance</span>'
)

fig.update_traces(
    textposition='top center',
    marker=dict(size=14, line=dict(width=1, color='white')),
    cliponaxis=False
)

fig.update_xaxes(title_text='X local (m)')
fig.update_yaxes(title_text='Y local (m)', scaleanchor='x', scaleratio=1)
fig.write_image(str(chart_path))

with open(meta_path, 'w', encoding='utf-8') as f:
    json.dump({
        'caption': '2D map of lamps in the local XY system',
        'description': 'Scatter plot the triangulated lamps in the local coordinate system, coloring them according to mean ray distance to check spatial stability.'
    }, f, ensure_ascii=False)

print(str(chart_path))
print(str(csv_out))