#include <opkele/types.h>
#include <opkele/exception.h>
#include <opkele/util.h>
#include <algorithm>

namespace opkele {
    using std::for_each;
    using std::unary_function;

    struct __om_copier : public unary_function<const string&,void> {
	public:
	    const basic_fields& from;
	    basic_fields& to;

	    __om_copier(basic_fields& t,const basic_fields& f)
		: from(f), to(t) { }

	    result_type operator()(argument_type f) {
		to.set_field(f,from.get_field(f)); }
    };

    basic_fields::basic_fields(const basic_fields& x) {
	x.copy_to(*this);
    }
    void basic_fields::copy_to(basic_fields& x) const {
	x.reset_fields();
	for_each(fields_begin(),fields_end(),
		__om_copier(x,*this) );
    }
    void basic_fields::append_to(basic_fields& x) const {
	for_each(fields_begin(),fields_end(),
		__om_copier(x,*this) );
    }

    struct __om_query_builder : public unary_function<const string&,void> {
	public:
	    const basic_fields& om;
	    bool first;
	    string& rv;
	    const char *pfx;

	    __om_query_builder(const char *p,string& r,const basic_fields& m)
		: om(m), first(true), rv(r), pfx(p) {
		    for_each(om.fields_begin(),om.fields_end(),*this);
		}
	    __om_query_builder(const char *p,string& r,const basic_fields& m,const string& u)
		: om(m), first(true), rv(r), pfx(p) {
		    rv = u;
		    if(rv.find('?')==string::npos)
			rv += '?';
		    else
			first = false;
		    for_each(om.fields_begin(),om.fields_end(),*this);
		}

	    result_type operator()(argument_type f) {
		if(first)
		    first = false;
		else
		    rv += '&';
		if(pfx) rv += pfx;
		rv+= f;
		rv += '=';
		rv += util::url_encode(om.get_field(f));
	    }
    };

    string basic_fields::append_query(const string& url,const char *pfx) const {
	string rv;
	return __om_query_builder(pfx,rv,*this,url).rv;
    }
    string basic_fields::query_string(const char *pfx) const {
	string rv;
	return __om_query_builder(pfx,rv,*this).rv;
    }

    void basic_fields::reset_fields() {
	throw not_implemented(OPKELE_CP_ "reset_fields() not implemented");
    }
    void basic_fields::set_field(const string&,const string&) {
	throw not_implemented(OPKELE_CP_ "set_field() not implemented");
    }
    void basic_fields::reset_field(const string&) {
	throw not_implemented(OPKELE_CP_ "reset_field() not implemented");
    }


}