Add python.nsh

Author: hoffmabc

windows/python.nsh

@@ -0,0 +1,56 @@
+/*
+ * python.nsh
+ *
+ * Configure Python
+ */
+
+!include StrFunc.nsh
+;${StrRep}
+
+; On Windows NT-derived operating systems, Python.org installer for Python 2.4
+; can be installed for all users or current user only.
+; define the following symbol to install if Python is installed only for current user.
+; !define INSTALL_IF_PYTHON_FOR_CURRENT_USER
+
+!define STRING_PYTHON_NOT_FOUND "Python is not installed on this system. $\nPlease install Python first. $\n$\nClick OK to cancel installation and remove installation Files."
+
+!define STRING_PYTHON_CURRENT_USER_FOUND "Python is installed for the current user only. $\n$\nOpenBazaar does not support use with Python so configured. $\n$\nClick OK to cancel installation and remove installation Files."
+
+var PythonRoot
+var PythonExecutable
+var StrNoUsablePythonFound
+
+Function ValidatePythonVersion
+  ClearErrors
+  MessageBox MB_OK "$PythonExecutable Here"
+  nsExec::ExecToStack '"$PythonExecutable" "-c" "import sys; ver=sys.version_info[:2]; exit({True:0,False:1}[ver<(2,7) or ver>(2,7)])"'
+FunctionEnd
+
+; This must be a macro because the registry root key cannot be a variable
+!macro EnumeratePython id hk_root hk
+  loop${id}:
+    EnumRegKey $1 HKLM "SOFTWARE\Python" $0
+    DetailPrint $1
+    StrCmp $1 "" done${id}
+    IntOp $0 $0 + 1
+    ReadRegStr $7 ${hk_root} "${hk}\$1\InstallPath" ""
+    StrCpy $PythonExecutable "$7\python.exe"
+    Call ValidatePythonVersion
+    Pop $7
+    StrCmp $7 0 ok loop${id}
+  done${id}:
+    StrCpy $PythonExecutable ""
+!macroend
+
+Function CheckForPython_new
+    !insertmacro EnumeratePython 1 HKLM Software\Python\PythonCore
+    !insertmacro EnumeratePython 2 HKLM Wow6432Node\Software\Python\PythonCore
+    !insertmacro EnumeratePython 3 HKCU Software\Python\PythonCore
+    !insertmacro EnumeratePython 4 HKCU Wow6432Node\Software\Python\PythonCore
+
+  ok:
+    MessageBox MB_OK "Found Python executable at '$PythonExecutable'"
+    Push $PythonExecutable
+    ${GetParent} $PythonExecutable $PythonRoot
+
+FunctionEnd