#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# Copyright (C) 2016, the Pyzo development team
#
# Pyzo is distributed under the terms of the (new) BSD License.
# The full license can be found in 'license.txt'.

"""
Pyzo is a cross-platform Python IDE focused on
interactivity and introspection, which makes it very suitable for
scientific computing. Its practical design is aimed at simplicity and
efficiency.

Pyzo is written in Python 3 and Qt. Binaries are available for Windows,
Linux, and Mac. For questions, there is a discussion group.

**Two components + tools**


Pyzo consists of two main components, the editor and the shell, and uses
a set of pluggable tools to help the programmer in various ways. Some
example tools are source structure, project manager, interactive help,
and workspace.

**Some key features**


* Powerful *introspection* (autocompletion, calltips, interactive help)
* Allows various ways to *run code interactively* or to run a file as a script.
* The shells runs in a *subprocess* and can therefore be interrupted or killed.
* *Multiple shells* can be used at the same time, and can be of different
  Python versions (from v2.4 to 3.x, including pypy)
* Support for using several *GUI toolkits* interactively: PySide, PyQt4,
  wx, fltk, GTK, Tk.
* Run IPython shell or native shell.
* *Full Unicode support* in both editor and shell.
* Various handy *tools*, plus the ability to make your own.
* Matlab-style *cell notation* to mark code sections (by starting a line
  with '##').

"""

# Set version number
__version__ = '4.3'

import os
import sys
import locale
import traceback

# Check Python version
if sys.version < '3':
    raise RuntimeError('Pyzo requires Python 3.x to run.')

# Make each OS find platform plugins etc.
if hasattr(sys, 'frozen') and sys.frozen:
    app_dir = os.path.dirname(sys.executable)
    if sys.platform.startswith('win'):
        os.environ['QT_QPA_PLATFORM_PLUGIN_PATH'] = app_dir
    if sys.platform.startswith('linux'):
        os.environ['QT_XKB_CONFIG_ROOT'] = '.'
        os.environ['FONTCONFIG_FILE'] = os.path.join(app_dir, 'source/pyzo/resources',
                                                    'fonts/linux_fonts.conf')

# Import yoton as an absolute package
from pyzo import yotonloader
from pyzo.util import paths

# If there already is an instance of Pyzo, and the user is trying an
# Pyzo command, we should send the command to the other process and quit.
# We do this here, were we have not yet loaded Qt, so we are very light.
from pyzo.core import commandline
if commandline.is_our_server_running():
    print('Started our command server')
else:
    # Handle command line args now
    res = commandline.handle_cmd_args()
    if res:
        print(res)
        sys.exit()
    else:
        # No args, proceed with starting up
        print('Our command server is *not* running')


from pyzo.util import zon as ssdf  # zon is ssdf-light
from pyzo.util.qt import QtCore, QtGui, QtWidgets

# Import language/translation tools
from pyzo.util._locale import translate, setLanguage

# Set environ to let kernel know some stats about us
os.environ['PYZO_PREFIX'] = sys.prefix
_is_pyqt4 = hasattr(QtCore, 'PYQT_VERSION_STR')
os.environ['PYZO_QTLIB'] = 'PyQt4' if _is_pyqt4 else 'PySide'


class MyApp(QtWidgets.QApplication):
    """ So we an open .py files on OSX.
    OSX is smart enough to call this on the existing process.
    """
    def event(self, event):
        if isinstance(event, QtGui.QFileOpenEvent):
            fname = str(event.file())
            if fname and fname != 'pyzo':
                sys.argv[1:] = []
                sys.argv.append(fname)
                res = commandline.handle_cmd_args()
                if not commandline.is_our_server_running():
                    print(res)
                    sys.exit()
        return QtWidgets.QApplication.event(self, event)

if not sys.platform.startswith('darwin'):
    MyApp = QtWidgets.QApplication

## Install excepthook
# In PyQt5 exceptions in Python will cuase an abort
# http://pyqt.sourceforge.net/Docs/PyQt5/incompatibilities.html

def pyzo_excepthook(type, value, tb):
    out = 'Uncaught Python exception: ' + str(value) + '\n'
    out += ''.join(traceback.format_list(traceback.extract_tb(tb)))
    out += '\n'
    sys.stderr.write(out)

sys.excepthook = pyzo_excepthook


## Define some functions


# todo: move some stuff out of this module ...

def getResourceDirs():
    """ getResourceDirs()
    Get the directories to the resources: (pyzoDir, appDataDir).
    Also makes sure that the appDataDir has a "tools" directory and
    a style file.
    """

#     # Get root of the Pyzo code. If frozen its in a subdir of the app dir
#     pyzoDir = paths.application_dir()
#     if paths.is_frozen():
#         pyzoDir = os.path.join(pyzoDir, 'source')
    pyzoDir = os.path.abspath(os.path.dirname(__file__))
    if '.zip' in pyzoDir:
        raise RuntimeError('The Pyzo package cannot be run from a zipfile.')

    # Get where the application data is stored (use old behavior on Mac)
    appDataDir = paths.appdata_dir('pyzo', roaming=True, macAsLinux=True)

    # Create tooldir if necessary
    toolDir = os.path.join(appDataDir, 'tools')
    if not os.path.isdir(toolDir):
        os.mkdir(toolDir)

    return pyzoDir, appDataDir


def resetConfig(preserveState=True):
    """ resetConfig()
    Replaces the config file with the default and prevent Pyzo from storing
    its config on the next shutdown.
    """
    # Get filenames
    configFileName1 = os.path.join(pyzoDir, 'resources', 'defaultConfig.ssdf')
    configFileName2 = os.path.join(appDataDir, 'config.ssdf')
    # Read, edit, write
    tmp = ssdf.load(configFileName1)
    if preserveState:
        tmp.state = config.state
    ssdf.save(configFileName2, tmp)
    global _saveConfigFile
    _saveConfigFile = False
    print("Replaced config file. Restart Pyzo to revert to the default config.")


def loadConfig(defaultsOnly=False):
    """ loadConfig(defaultsOnly=False)
    Load default configuration file and that of the user (if it exists).
    Any missing fields in the user config are set to the defaults.
    """

    # Function to insert names from one config in another
    def replaceFields(base, new):
        for key in new:
            if key in base and isinstance(base[key], ssdf.Struct):
                replaceFields(base[key], new[key])
            else:
                base[key] = new[key]

    # Reset our pyzo.config structure
    ssdf.clear(config)

    # Load default and inject in the pyzo.config
    fname = os.path.join(pyzoDir, 'resources', 'defaultConfig.ssdf')
    defaultConfig = ssdf.load(fname)
    replaceFields(config, defaultConfig)

    # Platform specific keybinding: on Mac, Ctrl+Tab (actually Cmd+Tab) is a system shortcut
    if sys.platform == 'darwin':
        config.shortcuts2.view__select_previous_file = 'Alt+Tab,'

    # Load user config and inject in pyzo.config
    fname = os.path.join(appDataDir, "config.ssdf")
    if os.path.isfile(fname):
        userConfig = ssdf.load(fname)
        replaceFields(config, userConfig)


def saveConfig():
    """ saveConfig()
    Save all configureations to file.
    """

    # Let the editorStack save its state
    if editors:
        editors.saveEditorState()

    # Let the main window save its state
    if main:
        main.saveWindowState()

    # Store config
    if _saveConfigFile:
        ssdf.save( os.path.join(appDataDir, "config.ssdf"), config )


def start():
    """ Run Pyzo.
    """

    # Do some imports
    from pyzo.core import pyzoLogging # to start logging asap
    from pyzo.core.main import MainWindow

    # Apply users' preferences w.r.t. date representation etc
    # this is required for e.g. strftime("%c")
    # Just using '' does not seem to work on OSX. Thus
    # this odd loop.
    #locale.setlocale(locale.LC_ALL, "")
    for x in ('', 'C', 'en_US', 'en_US.utf8', 'en_US.UTF-8'):
        try:
            locale.setlocale(locale.LC_ALL, x)
            break
        except locale.Error:
            pass

    # Set to be aware of the systems native colors, fonts, etc.
    QtWidgets.QApplication.setDesktopSettingsAware(True)

    # Instantiate the application
    QtWidgets.qApp = MyApp(sys.argv)  # QtWidgets.QApplication([])

    # Choose language, get locale
    appLocale = setLanguage(config.settings.language)

    # Create main window, using the selected locale
    frame = MainWindow(None, appLocale)

    # Enter the main loop
    QtWidgets.qApp.exec_()


## Init

# List of names that are later overriden (in main.py)
editors = None # The editor stack instance
shells = None # The shell stack instance
main = None # The mainwindow
icon = None # The icon
parser = None # The source parser
status = None # The statusbar (or None)

# Get directories of interest
pyzoDir, appDataDir = getResourceDirs()

# Whether the config file should be saved
_saveConfigFile = True

# Create ssdf in module namespace, and fill it
config = ssdf.new()
loadConfig()

# Init default style name (set in main.restorePyzoState())
defaultQtStyleName = ''
