====== Input method in FreeBSD virtual terminal (Week4) ======

Date: 06/27-07/04

===== Python Bindings =====
This week I decided to replace //SWIG// with //ctypes//. The reason is that I found it's quite complicated to return a void pointer or a C-style string in //SWIG//. While in //ctypes// I can set a functions's return type to //c_void_p// to return a void pointer, and one can even cast it into //c_char_p// to convert it into a Python string.

Take function //rime_wrapper_get_input_str()// as an example:

<code>
rime_wrapper_get_input_str.restype = c_void_p
</code>

Then convert the type to char pointer, copy the string and free the origin pointer:

<code>
_input_str = rime_wrapper_get_input_str(self.rime_wrapper_ptr)
input_str = cast(_input_str, c_char_p).value.decode('utf-8')
rime_wrapper_free_str(_input_str)
return input_str
</code>

Moreover, I found it's not as difficult as I thought few weeks ago to define the contents of a C struct in Python, and it turned out that it paid off since I could directly access the members in a structure in Python without processing them in C.

===== Tmux-rime =====

The origin idea of the server is acted as a rime session manager, which can handle multiple sessions and send different actions to different sessions depending on the //session_id// sent by the client. Later I found ''%%RimeAPI%%'' only can be initialized once during the program runtime, so the server can no longer handle multiple sessions simultaneously. Therefore I modified both client and server such that only when the user presses the tmux-rime prefix key do the server start.

I also had established and implemented the six basic commands for the server:
  * ''%%commit_raw_str%%'': Commit the raw input text   
  * ''%%delete_char%%'': Delete a char in composing  
  * ''%%handle_key%%'': Handle a regular key 
  * ''%%clear_state%%'': Clear the current composition 
  * ''%%get_output_text%%'': Get the text that will be inserted later
  * ''%%get_status_str%%'': Get the display string of the status bar

As for the tmux part, I had implemented these two functions:
  * Text inserting: Inserting the CJK characters in where the cursor places
  * IME status bar: Show preedit string and candidates in the tmux status bar