/* Authorship:
   Written by Jeff Dunlop.  Explicitly released to the public domain.  
   There is no code contained within that is derivative of any 
   copyrighted  code.

   Predictability:  
   Template expansion is currently supported for the following 
   constructs: if(), while(), do while (), for() and switch().  It 
   occurs if there is only one group of contiguous alphabetic characters 
   preceding the cursor, the group of characters is recognized as a 
   substring of a supported construct and the space-bar is pressed.
   
   Configurability:  
   This source is active if c-mode is active.  In general, CloseBack and 
   Topindent govern indentation behavior.  The only issue remaining to 
   be resolved is whether your opening bracket is on its own line.  This 
   is controlled by old_style, which defaults to false.  A relatively 
   non-issue is whether templates are turned on (the default).  Setting 
   enable_templates to 0 disables them.  If you find working around 
   expansion when you know it's going to happen a pain, you might try 
   assigning expansion to another key or alternately, assign a space 
   character to a different key.  However, it is not too difficult to 
   use the right-arrow key in cases where you want lateral movement 
   without expansion as long as virtual-space is enabled. */

keytable c_tab;                 /* key table for c mode */

#include <eel.h>

int old_style = 0,
    enable_templates = 1;

expand_if(where)
{
	/* 1. Examine the line to see if we should expand */
        char *template = "if (  )\n{\n}",
             *oldtemplate = "if (  ) {\n}",
             *p = where + ( old_style ? oldtemplate : template );
             
        while ( *p )
        {
            insert(*p);
            if ( *p == '{' || *p == '}')
            {
                fix_c_indentation();
            }
            p++;
        }
        search(-1, ")");
        point--;        
}	

expand_while(where)
{
    char *template = "while (  )\n{\n}",
         *oldtemplate = "while (  ) {\n}",
         *p = where + ( old_style ? oldtemplate : template );
    
    while ( *p )
    {
        insert(*p);
        if ( *p == '{' || *p == '}')
            fix_c_indentation();
        p++;
    }
    search(-1, ")");
    point--;
}

expand_for(where)
{
    char *template = "for ( ; ; )\n{\n}",
         *oldtemplate = "for ( ; ; ) {\n}",
         *p = where + ( old_style ? oldtemplate : template );
         
    while ( *p )
    {
        insert(*p);
        if ( *p == '{' || *p == '}')
            fix_c_indentation();
        p++;
    }
    search(-1, ")");
    point -= 4;
}

expand_dowhile(where)
{
    char *template = "do\n{\n} while (  );",
         *oldtemplate = "do {\n} while (  );",
         *p = where + ( old_style ? oldtemplate : template );
         
    while ( *p )
    {
        insert(*p);
        if ( *p == '{' || *p == '}')
            fix_c_indentation();
        p++;
    }
    search(-1, ")");
    point--;
}

expand_switch(where)
{
    char *template = "switch (  )\n{\ncase:\n};",
         *oldtemplate = "switch (  ) {\ncase:\n};",
         *p = where + ( old_style ? oldtemplate : template );
         
    while ( *p )
    {
        insert(*p);
        if ( *p == '{' || *p == '}' || *p == ':')
            fix_c_indentation();
        p++;
    }
    search(-1, ")");
    point--;
} 

expand_comment()
{
}

int max(a, b)
{
    return a < b ? a : b;
}

expand_template() on c_tab[' ']
{
    char buf[80];
    
    int len, here = point;
    
    if ( !enable_templates )
    {
        insert(' ');
        return;
    }
        
    if ( !all_blanks(point, give_end_line()) ) 
    {
        insert(' ');
        return;
    }
    
    re_search(-1, "[^a-z]");
    if ( point < give_begin_line() )
        point = give_begin_line();
    if ( isspace(curchar()) )
        point++;
    if ( !all_blanks(give_begin_line(), point) )
    {
        point = here;
        insert(' ');
        return;
    }
    len = here - point;
    if ( len < 80 )
    {
        grab(point, here, buf);
        buf[len] = 0;
    }
    else
    {
        point = here;
        insert(' ');
        return;
    }
    say("buf=%s, len=%d", buf, len);
    if ( len < 1 )
    {
        point = here;
        insert(' ');
        return;
    }
    if ( strncmp(buf, "if", max(2, len)) == 0 )
    {
        point = here;
        expand_if(len);
        return;
    }            
    if ( strncmp(buf, "while", max(5, len)) == 0 )
    {
        point = here;
        expand_while(len);
        return;
    }
    if ( strncmp(buf, "for", max(3, len)) == 0 )
    {
        point = here;
        expand_for(len);
        return;
    }
    if ( strncmp(buf, "do", max(2, len)) == 0 )
    {
        point = here;
        expand_dowhile(len);
        return;
    }
    if ( strncmp(buf, "switch", max(5, len)) == 0 )
    {
        point = here;
        expand_switch(len);
        return;
    }
    point = here;
    insert(' ');
    return;
}