"""
@package startup.guiutils

@brief General GUI-dependent utilities for GUI startup of GRASS GIS

(C) 2018 by Vaclav Petras the GRASS Development Team

This program is free software under the GNU General Public License
(>=v2). Read the file COPYING that comes with GRASS for details.

@author Vaclav Petras <wenzeslaus gmail com>
@author Linda Kladivova <l.kladivova@seznam.cz>

This is for code which depend on something from GUI (wx or wxGUI).
"""


import os
import sys
import wx

import grass.script as gs
from grass.script import gisenv
from grass.grassdb.checks import mapset_exists, location_exists
from grass.grassdb.create import create_mapset, get_default_mapset_name
from grass.grassdb.manage import (
    delete_mapset,
    delete_location,
    rename_mapset,
    rename_location,
)

from core import globalvar
from core.gcmd import GError, GMessage, DecodeString, RunCommand
from gui_core.dialogs import TextEntryDialog
from location_wizard.dialogs import RegionDef
from gui_core.widgets import GenericMultiValidator


def SetSessionMapset(database, location, mapset):
    """Sets database, location and mapset for the current session"""
    RunCommand("g.gisenv", set="GISDBASE=%s" % database)
    RunCommand("g.gisenv", set="LOCATION_NAME=%s" % location)
    RunCommand("g.gisenv", set="MAPSET=%s" % mapset)


class MapsetDialog(TextEntryDialog):
    def __init__(self, parent=None, default=None, message=None, caption=None,
                 database=None, location=None):
        self.database = database
        self.location = location

        # list of tuples consisting of conditions and callbacks
        checks = [(gs.legal_name, self._nameValidationFailed),
                  (self._checkMapsetNotExists, self._mapsetAlreadyExists),
                  (self._checkOGR, self._reservedMapsetName)]
        validator = GenericMultiValidator(checks)

        TextEntryDialog.__init__(
            self, parent=parent,
            message=message,
            caption=caption,
            defaultValue=default,
            validator=validator,
        )

    def _nameValidationFailed(self, ctrl):
        message = _(
            "Name '{}' is not a valid name for location or mapset. "
            "Please use only ASCII characters excluding characters {} "
            "and space.").format(ctrl.GetValue(), '/"\'@,=*~')
        GError(parent=self, message=message, caption=_("Invalid name"))

    def _checkOGR(self, text):
        """Check user's input for reserved mapset name."""
        if text.lower() == 'ogr':
            return False
        return True

    def _reservedMapsetName(self, ctrl):
        message = _(
            "Name '{}' is reserved for direct "
            "read access to OGR layers. Please use "
            "another name for your mapset.").format(ctrl.GetValue())
        GError(parent=self, message=message,
               caption=_("Reserved mapset name"))

    def _checkMapsetNotExists(self, text):
        """Check whether user's input mapset exists or not."""
        if mapset_exists(self.database, self.location, text):
            return False
        return True

    def _mapsetAlreadyExists(self, ctrl):
        message = _(
            "Mapset '{}' already exists. Please consider using "
            "another name for your mapset.").format(ctrl.GetValue())
        GError(parent=self, message=message,
               caption=_("Existing mapset path"))


class LocationDialog(TextEntryDialog):
    def __init__(self, parent=None, default=None, message=None, caption=None,
                 database=None):
        self.database = database

        # list of tuples consisting of conditions and callbacks
        checks = [(gs.legal_name, self._nameValidationFailed),
                  (self._checkLocationNotExists, self._locationAlreadyExists)]
        validator = GenericMultiValidator(checks)

        TextEntryDialog.__init__(
            self, parent=parent,
            message=message,
            caption=caption,
            defaultValue=default,
            validator=validator,
        )

    def _nameValidationFailed(self, ctrl):
        message = _(
            "Name '{}' is not a valid name for location or mapset. "
            "Please use only ASCII characters excluding characters {} "
            "and space.").format(ctrl.GetValue(), '/"\'@,=*~')
        GError(parent=self, message=message, caption=_("Invalid name"))

    def _checkLocationNotExists(self, text):
        """Check whether user's input location exists or not."""
        if location_exists(self.database, text):
            return False
        return True

    def _locationAlreadyExists(self, ctrl):
        message = _(
            "Location '{}' already exists. Please consider using "
            "another name for your location.").format(ctrl.GetValue())
        GError(parent=self, message=message,
               caption=_("Existing location path"))


# TODO: similar to (but not the same as) read_gisrc function in grass.py
def read_gisrc():
    """Read variables from a current GISRC file

    Returns a dictionary representation of the file content.
    """
    grassrc = {}

    gisrc = os.getenv("GISRC")

    if gisrc and os.path.isfile(gisrc):
        try:
            rc = open(gisrc, "r")
            for line in rc.readlines():
                try:
                    key, val = line.split(":", 1)
                except ValueError as e:
                    sys.stderr.write(
                        _('Invalid line in GISRC file (%s):%s\n' % (e, line)))
                grassrc[key.strip()] = DecodeString(val.strip())
        finally:
            rc.close()

    return grassrc


def GetVersion():
    """Gets version and revision

    Returns tuple `(version, revision)`. For standard releases revision
    is an empty string.

    Revision string is currently wrapped in parentheses with added
    leading space. This is an implementation detail and legacy and may
    change anytime.
    """
    versionFile = open(os.path.join(globalvar.ETCDIR, "VERSIONNUMBER"))
    versionLine = versionFile.readline().rstrip('\n')
    versionFile.close()
    try:
        grassVersion, grassRevision = versionLine.split(' ', 1)
        if grassVersion.endswith('dev'):
            grassRevisionStr = ' (%s)' % grassRevision
        else:
            grassRevisionStr = ''
    except ValueError:
        grassVersion = versionLine
        grassRevisionStr = ''
    return (grassVersion, grassRevisionStr)


def create_mapset_interactively(guiparent, grassdb, location):
    """
    Create new mapset
    """
    dlg = MapsetDialog(
        parent=guiparent,
        default=get_default_mapset_name(),
        message=_("Name for the new mapset:"),
        caption=_("Create new mapset"),
        database=grassdb,
        location=location,
    )

    mapset = None
    if dlg.ShowModal() == wx.ID_OK:
        mapset = dlg.GetValue()
        try:
            create_mapset(grassdb, location, mapset)
        except OSError as err:
            mapset = None
            GError(
                parent=guiparent,
                message=_("Unable to create new mapset: {}").format(err),
                showTraceback=False,
            )
    dlg.Destroy()
    return mapset


def create_location_interactively(guiparent, grassdb):
    """
    Create new location using Location Wizard.

    Returns tuple (database, location, mapset) where mapset is "PERMANENT"
    by default or another mapset a user created and may want to switch to.
    """
    from location_wizard.wizard import LocationWizard

    gWizard = LocationWizard(parent=guiparent,
                             grassdatabase=grassdb)

    if gWizard.location is None:
        gWizard_output = (None, None, None)
        # Returns Nones after Cancel
        return gWizard_output

    if gWizard.georeffile:
        message = _(
            "Do you want to import {}"
            "to the newly created location?"
        ).format(gWizard.georeffile)
        dlg = wx.MessageDialog(parent=guiparent,
                               message=message,
                               caption=_("Import data?"),
                               style=wx.YES_NO | wx.YES_DEFAULT |
                               wx.ICON_QUESTION)
        dlg.CenterOnParent()
        if dlg.ShowModal() == wx.ID_YES:
            import_file(guiparent, gWizard.georeffile)
        dlg.Destroy()

    if gWizard.default_region:
        defineRegion = RegionDef(guiparent, location=gWizard.location)
        defineRegion.CenterOnParent()
        defineRegion.ShowModal()
        defineRegion.Destroy()

    if gWizard.user_mapset:
        mapset = create_mapset_interactively(guiparent,
                                             gWizard.grassdatabase,
                                             gWizard.location)
        # Returns database and location created by user
        # and a mapset user may want to switch to
        gWizard_output = (gWizard.grassdatabase, gWizard.location,
                          mapset)
    else:
        # Returns PERMANENT mapset when user mapset not defined
        gWizard_output = (gWizard.grassdatabase, gWizard.location,
                          "PERMANENT")
    return gWizard_output


def rename_mapset_interactively(guiparent, grassdb, location, mapset):
    """Rename mapset with user interaction.

    If PERMANENT or current mapset found, rename operation is not performed.

    Exceptions during renaming are handled in this function.

    Returns newmapset if there was a change or None if the mapset cannot be
    renamed (see above the possible reasons) or if another error was encountered.
    """
    genv = gisenv()

    # Check selected mapset and remember issue.
    # Each error is reported only once (using elif).
    mapset_path = os.path.join(grassdb, location, mapset)
    newmapset = None
    issue = None

    # Check for permanent mapsets
    if mapset == "PERMANENT":
        issue = _("<{}> is required for a valid location.").format(mapset_path)
    # Check for current mapset
    elif (
            grassdb == genv['GISDBASE'] and
            location == genv['LOCATION_NAME'] and
            mapset == genv['MAPSET']
    ):
        issue = _("<{}> is the current mapset.").format(mapset_path)

    # If an issue, display the warning message and do not rename mapset
    if issue:
        dlg = wx.MessageDialog(
            parent=guiparent,
            message=_(
                "Cannot rename selected mapset for the following reason:\n\n"
                "{}\n\n"
                "No mapset will be renamed."
            ).format(issue),
            caption=_("Unable to rename selected mapset"),
            style=wx.OK | wx.ICON_WARNING
        )
        dlg.ShowModal()
    else:
        dlg = MapsetDialog(
            parent=guiparent,
            default=mapset,
            message=_("Current name: {}\n\nEnter new name:").format(mapset),
            caption=_("Rename selected mapset"),
            database=grassdb,
            location=location,
        )

        if dlg.ShowModal() == wx.ID_OK:
            newmapset = dlg.GetValue()
            try:
                rename_mapset(grassdb, location, mapset, newmapset)
            except OSError as err:
                newmapset = None
                wx.MessageBox(
                    parent=guiparent,
                    caption=_("Error"),
                    message=_("Unable to rename mapset.\n\n{}").format(err),
                    style=wx.OK | wx.ICON_ERROR | wx.CENTRE,
                )
    dlg.Destroy()
    return newmapset


def rename_location_interactively(guiparent, grassdb, location):
    """Rename location with user interaction.

    If current location found, rename operation is not performed.

    Exceptions during renaming are handled in this function.

    Returns newlocation if there was a change or None if the location cannot be
    renamed (see above the possible reasons) or if another error was encountered.
    """
    genv = gisenv()

    # Check selected location and remember issue.
    # Each error is reported only once (using elif).
    location_path = os.path.join(grassdb, location)
    newlocation = None
    issue = None

    # Check for current location
    if (
            grassdb == genv['GISDBASE'] and
            location == genv['LOCATION_NAME']
    ):
        issue = _("<{}> is the current location.").format(location_path)

    # If an issue, display the warning message and do not rename location
    if issue:
        dlg = wx.MessageDialog(
            parent=guiparent,
            message=_(
                "Cannot rename selected location for the following reason:\n\n"
                "{}\n\n"
                "No location will be renamed."
            ).format(issue),
            caption=_("Unable to rename selected location"),
            style=wx.OK | wx.ICON_WARNING
        )
        dlg.ShowModal()
    else:
        dlg = LocationDialog(
            parent=guiparent,
            default=location,
            message=_("Current name: {}\n\nEnter new name:").format(location),
            caption=_("Rename selected location"),
            database=grassdb,
        )

        if dlg.ShowModal() == wx.ID_OK:
            newlocation = dlg.GetValue()
            try:
                rename_location(grassdb, location, newlocation)
            except OSError as err:
                newlocation = None
                wx.MessageBox(
                    parent=guiparent,
                    caption=_("Error"),
                    message=_("Unable to rename location.\n\n{}").format(err),
                    style=wx.OK | wx.ICON_ERROR | wx.CENTRE,
                )
    dlg.Destroy()
    return newlocation


def download_location_interactively(guiparent, grassdb):
    """
    Download new location using Location Wizard.

    Returns tuple (database, location, mapset) where mapset is "PERMANENT"
    by default or in future it could be the mapset the user may want to
    switch to.
    """
    from startup.locdownload import LocationDownloadDialog

    result = (None, None, None)
    loc_download = LocationDownloadDialog(parent=guiparent,
                                          database=grassdb)
    loc_download.Centre()
    loc_download.ShowModal()

    if loc_download.GetLocation() is not None:
        # Returns database and location created by user
        # and a mapset user may want to switch to
        result = (grassdb, loc_download.GetLocation(), "PERMANENT")
    loc_download.Destroy()
    return result


def delete_mapset_interactively(guiparent, grassdb, location, mapset):
    """Delete one mapset with user interaction.

    This is currently just a convenience wrapper for delete_mapsets_interactively().
    """
    mapsets = [(grassdb, location, mapset)]
    return delete_mapsets_interactively(guiparent, mapsets)


def delete_mapsets_interactively(guiparent, mapsets):
    """Delete multiple mapsets with user interaction.

    Parameter *mapsets* is a list of tuples (database, location, mapset).

    If PERMANENT or current mapset found, delete operation is not performed.

    Exceptions during deletation are handled in this function.

    Returns True if there was a change, i.e., all mapsets were successfuly deleted
    or at least one mapset was deleted. Returns False if one or more mapsets cannot be
    deleted (see above the possible reasons) or if an error was encountered when
    deleting the first mapset in the list.
    """
    genv = gisenv()
    issues = []
    deletes = []

    # Check selected mapsets and remember issue.
    # Each error is reported only once (using elif).
    for grassdb, location, mapset in mapsets:
        mapset_path = os.path.join(grassdb, location, mapset)
        # Check for permanent mapsets
        if mapset == "PERMANENT":
            issue = _("<{}> is required for a valid location.").format(mapset_path)
            issues.append(issue)
        # Check for current mapset
        elif (
                grassdb == genv['GISDBASE'] and
                location == genv['LOCATION_NAME'] and
                mapset == genv['MAPSET']
        ):
            issue = _("<{}> is the current mapset.").format(mapset_path)
            issues.append(issue)
        # No issue detected
        else:
            deletes.append(mapset_path)

    modified = False  # True after first successful delete
    # If any issues, display the warning message and do not delete anything
    if issues:
        issues = "\n".join(issues)
        dlg = wx.MessageDialog(
            parent=guiparent,
            message=_(
                "Cannot delete one or more mapsets for the following reasons:\n\n"
                "{}\n\n"
                "No mapsets will be deleted."
            ).format(issues),
            caption=_("Unable to delete selected mapsets"),
            style=wx.OK | wx.ICON_WARNING
        )
        dlg.ShowModal()
    else:
        deletes = "\n".join(deletes)
        dlg = wx.MessageDialog(
            parent=guiparent,
            message=_(
                "Do you want to continue with deleting"
                " one or more of the following mapsets?\n\n"
                "{}\n\n"
                "All maps included in these mapsets will be permanently deleted!"
            ).format(deletes),
            caption=_("Delete selected mapsets"),
            style=wx.YES_NO | wx.NO_DEFAULT | wx.ICON_QUESTION,
        )
        if dlg.ShowModal() == wx.ID_YES:
            try:
                for grassdb, location, mapset in mapsets:
                    delete_mapset(grassdb, location, mapset)
                    modified = True
                dlg.Destroy()
                return modified
            except OSError as error:
                wx.MessageBox(
                    parent=guiparent,
                    caption=_("Error when deleting mapsets"),
                    message=_(
                        "The following error occured when deleting mapset <{path}>:"
                        "\n\n{error}\n\n"
                        "Deleting of mapsets was interrupted."
                    ).format(
                        path=os.path.join(grassdb, location, mapset),
                        error=error,
                    ),
                    style=wx.OK | wx.ICON_ERROR | wx.CENTRE,
                )
    dlg.Destroy()
    return modified


def delete_location_interactively(guiparent, grassdb, location):
    """Delete a location with user interaction.

    If current location found, delete operation is not performed.

    Exceptions during deletation are handled in this function.

    Returns True if there was a change, returns False if a location cannot be
    deleted (see above the possible reasons) or if another error was encountered.
    """
    genv = gisenv()
    issue = None

    # Check selected location and remember issue.
    # Each error is reported only once (using elif).
    location_path = os.path.join(grassdb, location)

    # Check for current location
    if (
        grassdb == genv['GISDBASE'] and
        location == genv['LOCATION_NAME']
    ):
        issue = _("<{}> is the current location.").format(location_path)

    modified = False  # True after first successful delete

    # If any issues, display the warning message and do not delete anything
    if issue:
        dlg = wx.MessageDialog(
            parent=guiparent,
            message=_(
                "Cannot delete selected location for the following reasons:\n\n"
                "{}\n\n"
                "No location will be deleted."
            ).format(issue),
            caption=_("Unable to delete selected location"),
            style=wx.OK | wx.ICON_WARNING
        )
        dlg.ShowModal()
    else:
        dlg = wx.MessageDialog(
            parent=guiparent,
            message=_(
                "Do you want to continue with deleting"
                "the following location?\n\n"
                "{}\n\n"
                "All mapsets included in this location will be permanently deleted!"
            ).format(location_path),
            caption=_("Delete selected location"),
            style=wx.YES_NO | wx.NO_DEFAULT | wx.ICON_QUESTION,
        )
        if dlg.ShowModal() == wx.ID_YES:
            try:
                delete_location(grassdb, location)
                modified = True
                dlg.Destroy()
                return modified
            except OSError as error:
                wx.MessageBox(
                    parent=guiparent,
                    caption=_("Error when deleting location"),
                    message=_(
                        "The following error occured when deleting location <{path}>:"
                        "\n\n{error}\n\n"
                        "Deleting was interrupted."
                    ).format(
                        path=os.path.join(grassdb, location),
                        error=error,
                    ),
                    style=wx.OK | wx.ICON_ERROR | wx.CENTRE,
                )
    dlg.Destroy()
    return modified


def import_file(guiparent, filePath):
    """Tries to import file as vector or raster.

    If successfull sets default region from imported map.
    """
    RunCommand('db.connect', flags='c')
    mapName = os.path.splitext(os.path.basename(filePath))[0]
    vectors = RunCommand('v.in.ogr', input=filePath, flags='l',
                         read=True)

    wx.BeginBusyCursor()
    wx.GetApp().Yield()
    if vectors:
        # vector detected
        returncode, error = RunCommand(
            'v.in.ogr', input=filePath, output=mapName, flags='e',
            getErrorMsg=True)
    else:
        returncode, error = RunCommand(
            'r.in.gdal', input=filePath, output=mapName, flags='e',
            getErrorMsg=True)
    wx.EndBusyCursor()

    if returncode != 0:
        GError(
            parent=guiparent,
            message=_(
                "Import of <%(name)s> failed.\n"
                "Reason: %(msg)s") % ({
                    'name': filePath,
                    'msg': error}))
    else:
        GMessage(
            message=_(
                "Data file <%(name)s> imported successfully. "
                "The location's default region was set from "
                "this imported map.") % {
                'name': filePath},
            parent=guiparent)