From 8fa62bba38f8b71f85dba7af9c3bdf1434d53900 Mon Sep 17 00:00:00 2001
From: L-Nafaryus <l.nafaryus@gmail.com>
Date: Fri, 14 Jan 2022 00:12:08 +0500
Subject: [PATCH] Mod: mesh and shape io Mod: mesh patches

---
 anisotropy/meshing/mesh.py  | 68 +++++++++++++++++++++++++++----------
 anisotropy/shaping/shape.py | 45 ++++++++++++++++++++++++
 2 files changed, 95 insertions(+), 18 deletions(-)

diff --git a/anisotropy/meshing/mesh.py b/anisotropy/meshing/mesh.py
index 310ced5..11cc720 100644
--- a/anisotropy/meshing/mesh.py
+++ b/anisotropy/meshing/mesh.py
@@ -7,9 +7,19 @@ from netgen import meshing
 from numpy import array
 import os
 
+
+class NoGeometrySpecified(Exception):
+    def __init__(self, msg):
+        super().__init__(self, msg)
+
+
+class NotSupportedMeshFormat(Exception):
+    def __init__(self, msg):
+        super().__init__(self, msg)
+
 class Mesh(object):
-    def __init__(self, shape):
-        self.geometry = OCCGeometry(shape)
+    def __init__(self, shape: OCCGeometry = None):
+        self.geometry = OCCGeometry(shape) if shape else None
         self.mesh = None
 
         #   Parameters
@@ -43,15 +53,44 @@ class Mesh(object):
         )
 
     def build(self):
-        self.mesh = self.geometry.GenerateMesh(self.parameters)
+        if self.geometry:
+            self.mesh = self.geometry.GenerateMesh(self.parameters)
 
-    def export(self, filename: str):
-        """Export a shape.
+        else:
+            raise NoGeometrySpecified("Specify a geometry to build a mesh")
+
+    formats = {
+        "vol": "Netgen Format",
+        "mesh": "Neutral Format",
+        "msh": "Gmsh2 Format"
+    }
+
+    def load(self, filename: str):
+        """Import a mesh.
         
-        Supported formats: vol, mesh.
+        Use `Mesh.formats` to see supported formats.
         
         :param filename:
-            Name of the file to store the given shape in.
+            Name of the file to store the given mesh in.
+        """
+        ext = os.path.splitext(filename)[1][1: ]
+
+        if ext in self.formats.keys():
+            self.mesh = meshing.Mesh()
+            self.mesh.Load(filename)
+
+        else:
+            raise NotSupportedMeshFormat(f"Mesh format '{ ext }' is not supported")
+        
+        return self
+
+    def export(self, filename: str):
+        """Export a mesh.
+        
+        Use `Mesh.formats` to see supported formats.
+        
+        :param filename:
+            Name of the file to store the given mesh in.
         
         :return:
             Output, error messages and returncode
@@ -63,20 +102,13 @@ class Mesh(object):
             if ext == "vol":
                 self.mesh.Save(filename)
             
-            elif ext == "mesh":
-                self.mesh.Export(filename, "Neutral Format")
-
-            elif ext == "msh":
-                self.mesh.Export(filename, "Gmsh2 Format")
+            elif ext in self.formats.keys():
+                self.mesh.Export(filename, self.formats[ext])
 
             else:
-                raise NotImplementedError(f"Mesh format '{ ext }' is not supported")
+                raise NotSupportedMeshFormat(f"Mesh format '{ ext }' is not supported")
             
-        except NotImplementedError as e:
-            err = e
-            returncode = 1
-        
-        except Exception as e:
+        except (NotSupportedMeshFormat, Exception) as e:
             err = e
             returncode = 1
         
diff --git a/anisotropy/shaping/shape.py b/anisotropy/shaping/shape.py
index 0c0a2d2..1707c52 100644
--- a/anisotropy/shaping/shape.py
+++ b/anisotropy/shaping/shape.py
@@ -56,6 +56,51 @@ class Shape(object):
 
         else:
             raise NotImplementedError(f"Shape format '{ext}' is not supported")
+        
+        return self
+
+    def patches(self, group: bool = False, shiftIndex: bool = False, prefix: str = None):
+        """Get patches indices with their names.
+
+        :param group:
+            Group indices together with the same patches names.
+
+        :param shiftIndex:
+            Start numerating with one instead of zero.
+
+        :param prefix:
+            Add string prefix to the index.
+
+        :return:
+            List if group = False else dictionary.
+        """
+        if group:
+            patches_ = {}
+
+            for idn, face in enumerate(self.shape.faces):
+                if shiftIndex:
+                    idn += 1
+
+                item = idn if not prefix else prefix + str(idn)
+                
+                if patches_.get(face.name):
+                    patches_[face.name].append(item)
+
+                else:
+                    patches_[face.name] = [ item ]
+
+        else:
+            patches_ = []
+
+            for idn, face in enumerate(self.shape.faces):
+                if shiftIndex:
+                    idn += 1
+                
+                item = idn if not prefix else prefix + str(idn)
+
+                patches_.append((item, face.name))
+
+        return patches_ 
 
     def normal(self, face: FACE) -> numpy.array:
         """