#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <ctype.h>
#include "fm.h"
#include "gc.h"
#include "terms.h"


/* Prototype declaration of internal functions */
#ifdef HAVE_READLINE
#include <readline/readline.h>
#else  /* ! HAVE_READLINE */
static char *readline( char* );
#endif /* ! HAVE_READLINE */
static TextList* split( char * );


/* Prototype declaration of command functions */
static void get( TextList* );
static void post( TextList* );
static void set( TextList* );
static void show( TextList* );
static void quit( TextList* );
static void help( TextList* );


/* Table of command functions */
struct {
    const char *name;
    const char *option_string;
    const char *help;
    void (*func)( TextList* );
} command_table[] = {
    { "get", "[-download_only] URL", "Retrieve URL.", get },
    { "post", "[-download_only] [-target TARGET] [-charset CHARSET]"
      " [-enctype ENCTYPE] [-body BODY] [-boundary BOUNDARY] [-length LEN] URL",
      "Retrieve URL.", post },
    { "set", "VARIABLE VALUE", "Set VALUE to VARIABLE.", set },
    { "show", "VARIABLE", "Show value of VARIABLE.", show },
    { "quit", "", "Quit program.", quit },
    { "help", "", "Display help messages.", help },
    { NULL, NULL, NULL, NULL },
};


/* Prototype declaration of functions to manipulate configuration variables */
static void set_column( TextList* );
static void show_column( TextList* );


/* Table of configuration variables */
struct {
    const char *name;
    void (*set_func)( TextList* );
    void (*show_func)( TextList* );
} variable_table[] = {
    { "column", set_column, show_column },
    { NULL, NULL, NULL },
};


static char* get_mime_charset_name( int coding ){
    Str r;
    switch( coding ){
	case CODE_EUC:
	    r = Strnew_charp( "euc-japan" );
	    break;
	case CODE_SJIS:
	    r = Strnew_charp( "shift_jis" );
	    break;
	case CODE_JIS_m:
	case CODE_JIS_n:
	case CODE_JIS_N:
	case CODE_JIS_j:
	case CODE_JIS_J:
	    r = Strnew_charp( "iso-2022-jp" );
	    break;
	default:
	    return NULL;
    }
    return r->ptr;
}


static void print_headers( Buffer *buf, int len ){
    TextListItem *tp;

    if( buf->document_header ){
	for( tp = buf->document_header->first; tp; tp = tp->next )
	    printf( "%s\n", tp->ptr );
    }
    printf( "w3m-content-type: %s\n", buf->type );
#ifdef JP_CHARSET
    if( buf->document_code )
	printf( "w3m-content-charset: %s\n",
		get_mime_charset_name( buf->document_code ) );
#endif
    if( len > 0 )
	printf( "w3m-content-length: %d\n", len );
}


static void print_formlist( int fid, FormList *fp ){
    Str s = Sprintf( "w3m-form: (formlist (fid %d) (action \"%s\") (method \"%s\")",
		     fid,
		     fp->action->ptr,
		     ( fp->method == FORM_METHOD_POST )? "post"
		     :( ( fp->method == FORM_METHOD_INTERNAL )? "internal" : "get" ) );
    if( fp->target )
	Strcat( s, Sprintf( " (target \"%s\")", fp->target ) );
    if( fp->charset )
	Strcat( s, Sprintf( " (charset '%s)", get_mime_charset_name(fp->charset) ) );
    if( fp->enctype == FORM_ENCTYPE_MULTIPART )
	Strcat_charp( s, " (enctype \"multipart/form-data\")" );
    if( fp->boundary )
	Strcat( s, Sprintf( " (boundary \"%s\")", fp->boundary ) );
    Strcat_charp( s, ")\n" );
    Strfputs( s, stdout );
}


static void internal_get( char *url, int flag, FormList *request ){
    Buffer *buf;

    backend_halfdump_str = Strnew_charp( "<pre>\n" );
    do_download = flag;
    buf = loadGeneralFile( url, NULL, NO_REFERER, 0, request );
    do_download = FALSE;
    if( buf != NULL && buf != NO_BUFFER ){
	if( !strcasecmp( buf->type, "text/html" ) ){
	    Strcat( backend_halfdump_str,
		    Sprintf( "</pre><title>%s</title>\n", buf->buffername ) );
	    print_headers( buf, backend_halfdump_str->length );
	    if( buf->formlist ){
		FormList *fp;
		int fid = 0;
		for( fp = buf->formlist; fp; fp = fp->next ) fid++;
		for( fp = buf->formlist; fp; fp = fp->next )
		    print_formlist( --fid, fp );
	    }
	    printf( "\n" );
	    Strfputs( backend_halfdump_str, stdout );
	} else {
	    if( !strcasecmp( buf->type, "text/plain" ) ){
		Line *lp;
		int len = 0;
		for( lp = buf->firstLine; lp; lp = lp->next ){
		    len += lp->len;
		    if( lp->lineBuf[lp->len-1] != '\n' ) len++;
		}
		print_headers( buf, len );
		printf( "\n" );
		saveBuffer( buf, stdout );
	    } else {
		print_headers( buf, 0 );
	    }
	}
    }
}


/* Command: get */
static void get( TextList *argv ){
    char *p, *url = NULL;
    int flag = FALSE;

    while(( p = popText( argv ) )){
	if( !strcasecmp( p, "-download_only" ) )
	    flag = TRUE;
	else
	    url = p;
    }
    if( url ){
	internal_get( url, flag, NULL );
    }
}


/* Command: post */
static void post( TextList *argv ){
    FormList *request;
    char *p, *target = NULL, *charset = NULL,
	*enctype = NULL, *body = NULL, *boundary = NULL, *url = NULL;
    int flag = FALSE, length = 0;

    while(( p = popText( argv ) )){
	if( !strcasecmp( p, "-download_only" ) )
	    flag = TRUE;
	else if( !strcasecmp( p, "-target" ) )
	    target = popText( argv );
	else if( !strcasecmp( p, "-charset" ) )
	    charset = popText( argv );
	else if( !strcasecmp( p, "-enctype" ) )
	    enctype = popText( argv );
	else if( !strcasecmp( p, "-body" ) )
	    body = popText( argv );
	else if( !strcasecmp( p, "-boundary" ) )
	    boundary = popText( argv );
	else if( !strcasecmp( p, "-length" ) )
	    length = atol( popText( argv ) );
	else
	    url = p;
    }
    if( url ){
	request = newFormList( NULL, "post", charset, enctype, target, NULL );
	request->body = body;
	request->boundary = boundary;
	request->length = ( length > 0 )? length : ( body ? strlen(body) : 0 );
	internal_get( url, flag, request );
    }
}


/* Command: set */
static void set( TextList *argv ){
    if( argv->nitem > 1 ){
	int i;
	for( i = 0; variable_table[i].name; i++ ){
	    if( !strcasecmp( variable_table[i].name, argv->first->ptr ) ){
		popText( argv );
		if( variable_table[i].set_func )
		    variable_table[i].set_func( argv );
		break;
	    }
	}
    }
}


/* Command: show */
static void show( TextList *argv ){
    if( argv->nitem >= 1 ){
	int i;
	for( i = 0; variable_table[i].name; i++ ){
	    if( !strcasecmp( variable_table[i].name, argv->first->ptr ) ){
		popText( argv );
		if( variable_table[i].show_func )
		    variable_table[i].show_func( argv );
		break;
	    }
	}
    }
}


/* Command: quit */
static void quit( TextList *argv ){
    deleteFiles();
#ifdef USE_COOKIE
    save_cookies();
#endif /* USE_COOKIE */
    exit(0);
}


/* Command: help */
static void help( TextList *argv ){
    int i;
    for( i = 0; command_table[i].name; i++ )
	printf( "%s %s\n    %s\n",
		command_table[i].name,
		command_table[i].option_string,
		command_table[i].help );
}


/* Sub command: set COLS */
static void set_column( TextList *argv ){
    if( argv->nitem == 1 ){
	COLS = atol( argv->first->ptr );
    }
}

/* Sub command: show COLS */
static void show_column( TextList *argv ){
    fprintf( stdout, "column=%d\n", COLS );
}


/* Call appropriate command function based on given string */
static void call_command_function( char *str ){
    int i;
    TextList *argv = split( str );
    if( argv->nitem > 0 ){
	for( i = 0; command_table[i].name; i++ ){
	    if( !strcasecmp( command_table[i].name, argv->first->ptr ) ){
		popText( argv );
		if( command_table[i].func )
		    command_table[i].func( argv );
		break;
	    }
	}
    }
}


/* Main function */
int backend( void ){
    char *str;
    extern int w3m_dump;		/* Declared in main.c. */

    w3m_dump     = FALSE;
    w3m_halfdump = FALSE;
    if (COLS == 0) COLS = 80;
#ifdef MOUSE
    mouse_end();
    use_mouse = FALSE;
#endif /* MOUSE */

    if( backend_batch_commands ){
	while(( str = popText(backend_batch_commands) ))
	    call_command_function( str );
    } else {
	while(( str = readline( "w3m> " ) ))
	    call_command_function( str );
    }
    quit( NULL );
    return 0;
}


/* Dummy function of readline(). */
#ifndef HAVE_READLINE
static char *readline( char *prompt ){
    Str s;
    fputs( prompt, stdout );
    fflush( stdout );
    s = Strfgets( stdin );
    if( feof( stdin ) && (strlen( s->ptr ) == 0) )
	return NULL;
    else
	return s->ptr;
}
#endif /* ! HAVE_READLINE */


/* Splits a string into a list of tokens and returns that list. */
static TextList* split( char *p ){
    int in_double_quote = FALSE, in_single_quote = FALSE;
    Str s = Strnew();
    TextList* tp = newTextList();

    for( ; *p; p++ ){
	switch( *p ){
	    case '"':
		if( in_single_quote )
		    Strcat_char( s, '"' );
		else
		    in_double_quote = !in_double_quote;
		break;
	    case '\'':
		if( in_double_quote )
		    Strcat_char( s, '\'' );
		else
		    in_single_quote = !in_single_quote;
		break;
	    case '\\':
		if( !in_single_quote ){
		    /* Process escape characters. */
		    p++;
		    switch( *p ){
			case 't':
			    Strcat_char( s, '\t' );
			    break;
			case 'r':
			    Strcat_char( s, '\r' );
			    break;
			case 'f':
			    Strcat_char( s, '\f' );
			    break;
			case 'n':
			    Strcat_char( s, '\n' );
			    break;
			case '\0':
			    goto LAST;
			default:
			    Strcat_char( s, *p );
		    }
		} else {
		    Strcat_char( s, *p );
		}
		break;
	    case ' ':
	    case '\t':
	    case '\r':
	    case '\f':
	    case '\n':
		/* Separators are detected. */
		if( in_double_quote || in_single_quote ){
		    Strcat_char( s, *p );
		} else if( s->length > 0 ){
		    pushText( tp, s->ptr );
		    s = Strnew();
		}
		break;
	    default:
		Strcat_char( s, *p );
	}
    }
LAST:
    if( s->length > 0 )
	pushText( tp, s->ptr );
    return tp;
}