#!/usr/bin/env python
# coding: utf-8

# # Getting Started with `pyhelios`
# ***

# <img align="right" src="https://github.com/3dgeo-heidelberg/helios/blob/dev/h++.png?raw=true" width="300">
# 
# This page will give an introduction on using HELIOS++ python bindings with `pyhelios`. 
# 
# `pyhelios` allows you to:
# 
# - Access and modify simulation configurations
# - Launch one or multiple simulations from your python script
# - Read point measurements and process them further in combination with other python modules

# ## Importing `pyhelios`
# The package `pyhelios` contains functions to create and work with simulations (e.g., `SimulationBuilder`) and a `util` subpackage, where tools for scene generation and flight planning are found.

# In[1]:


import pyhelios

print(pyhelios.__version__)


# In[2]:


import os

os.chdir("..")


# ## Logging Level and Random Seed

# In[3]:


# pyhelios.loggingQuiet()
# pyhelios.loggingSilent()
pyhelios.loggingDefault()
# pyhelios.loggingVerbose()
# pyhelios.loggingVerbose2()

# Set seed for default random number generator.
pyhelios.setDefaultRandomnessGeneratorSeed("123")


# ## Building a Simulation

# In[4]:


simBuilder = pyhelios.SimulationBuilder(
    "data/surveys/toyblocks/als_toyblocks.xml", ["assets/"], "output/"
)
# simBuilder.setNumThreads(1)  # use only one thread (to ensure reproducibility)
simBuilder.setLasOutput(True)
simBuilder.setZipOutput(True)
simBuilder.setCallbackFrequency(10)  # Run with callback
simBuilder.setFinalOutput(True)  # Return output at join
# simBuilder.setExportToFile(False)  # Disable export point cloud to file
simBuilder.setRebuildScene(True)

sim = simBuilder.build()


# ## Starting, Pausing and Getting the Simulation Status

# Simulations can also be paused, resumed and stopped:
# ```python
# sim.start()
# sim.pause()
# sim.resume()
# sim.stop()
# ```
# 
# With various functions, we can find out the simulation status.
# ```python
# sim.isStarted()
# sim.isRunning()
# sim.isPaused()
# sim.isStopped()
# sim.isFinished()
# ```

# In[5]:


import time

sim.start()

if sim.isStarted():
    print("Simulation is started!")

time.sleep(1.0)
sim.pause()

if sim.isPaused():
    print("Simulation is paused!")

if not sim.isRunning():
    print("Simulation is not running.")

time.sleep(5)
start_time = time.time()
sim.resume()

if sim.isRunning():
    print("Simulation is resumed!")

while sim.isRunning():
    duration = time.time() - start_time
    mins = duration // 60
    secs = duration % 60
    print(
        "\r"
        + "Simulation is running since {} min and {} sec. Please wait.".format(
            int(mins), int(secs)
        ),
        end="",
    )
    time.sleep(1)

if sim.isFinished():
    print("\nSimulation has finished.")


# ## Output Handling
# 
# If final output was enabled (`simBuilder.setFinalOutput(True)`)., the simulation output, i.e. measurement and trajectory points, can be accessed using `sim.join()`.

# In[6]:


# Create instance of PyHeliosOutputWrapper class using sim.join().
# Contains attributes 'measurements' and 'trajectories' which are Python wrappers
# of classes that contain the output vectors.
output = sim.join()

# Create instances of vector classes by accessing 'measurements' and 'trajectories' attributes of output wrapper.
measurements = output.measurements
trajectories = output.trajectories

# Each element of vectors contains a measurement point or point in trajectory respectively.
# Access through getPosition().
starting_point = trajectories[0].getPosition()
end_point = trajectories[len(trajectories) - 1].getPosition()

# Access individual x, y and z vals.
print(
    f"Trajectory starting point : ({starting_point.x}, {starting_point.y}, {starting_point.z})"
)
print(
    f"Trajectory end point : ({end_point.x:.1f}, {end_point.y:.1f}, {end_point.z:.1f})"
)


# `pyhelios` contains additional tools for output handling (pyhelios/output_handling.py). These allow to convert the trajectory and point outputs to lists or numpy arrays.

# In[7]:


meas_array, traj_array = pyhelios.outputToNumpy(output)


# In[8]:


import numpy as np

np.set_printoptions(formatter={"float": "{0:0.3f}".format})
print(
    f"""
First three rows of measurement array:

{meas_array[:3, :]}

First three rows of trajectory array:

{traj_array[:3, :]}
"""
)


# Columns of the measurements array:
# 
# |    0   |    1   |    2   |    3   |    4   |    5   |    6   |    7   |    8   |    9   |   10   |   11   |   12   |   13   |   14   |   15   |
# |:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|:------:|
# | pos.x | pos.y | pos.z | ori.x | ori.y | ori.z | dir.x | dir.y | dir.z | intensity | echoWidth | NumberOfReturns | ReturnNumber | FullwaveIndex | classification | gpsTime |
# 
# 
# Columns of the trajectories array:
# 
# 
# |    0   |    1   |    2   |    3   |    4   |    5   |    6   |
# |:------:|:------:|:------:|:------:|:------:|:------:|:------:|
# | pos.x | pos.y | pos.z | gpsTime | roll | pitch | yaw |