/*
 * biblio.c: process the bibliography
 */

#include <assert.h>
#include "halibut.h"

static wchar_t *gentext(int num) {
    wchar_t text[22];
    wchar_t *p = text + lenof(text);
    *--p = L'\0';
    *--p = L']';
    while (num != 0) {
	assert(p > text);
	*--p = L"0123456789"[num % 10];
	num /= 10;
    }
    assert(p > text);
    *--p = L'[';
    return ustrdup(p);
}

static void cite_biblio(keywordlist *kl, wchar_t *key, filepos fpos) {
    keyword *kw = kw_lookup(kl, key);
    if (!kw)
	error(err_nosuchkw, &fpos, key);
    else {
	/*
	 * We've found a \k reference. If it's a
	 * bibliography entry ...
	 */
	if (kw->para->type == para_Biblio) {
	    /*
	     * ... then mark the paragraph as cited.
	     */
	    kw->para->type = para_BiblioCited;
	}
    }
}

/*
 * Make a pass through the source form, generating citation formats
 * for bibliography entries and also marking which bibliography
 * entries are actually cited (or \nocite-ed).
 */

void gen_citations(paragraph *source, keywordlist *kl) {
    paragraph *para;
    int bibnum = 0;

    for (para = source; para; para = para->next) {
	word *ptr;

	/*
	 * \BR and \nocite paragraphs get special processing here.
	 */
	if (para->type == para_BR) {
	    keyword *kw = kw_lookup(kl, para->keyword);
	    if (!kw) {
		error(err_nosuchkw, &para->fpos, para->keyword);
	    } else if (kw->text) {
		error(err_multiBR, &para->fpos, para->keyword);
	    } else {
		kw->text = dup_word_list(para->words);
	    }
	} else if (para->type == para_NoCite) {
	    wchar_t *wp = para->keyword;
	    while (*wp) {
		cite_biblio(kl, wp, para->fpos);
		wp = uadv(wp);
	    }
	}

	/*
	 * Scan for keyword references.
	 */
	for (ptr = para->words; ptr; ptr = ptr->next) {
	    if (ptr->type == word_UpperXref ||
		ptr->type == word_LowerXref)
		cite_biblio(kl, ptr->text, ptr->fpos);
	}
    }

    /*
     * We're now almost done; all that remains is to scan through
     * the cited bibliography entries and invent default citation
     * texts for the ones that don't already have explicitly
     * provided \BR text.
     */
    for (para = source; para; para = para->next) {
	if (para->type == para_BiblioCited) {
	    keyword *kw = kw_lookup(kl, para->keyword);
	    assert(kw != NULL);
	    if (!kw->text) {
		word *wd = smalloc(sizeof(word));
		wd->text = gentext(++bibnum);
		wd->type = word_Normal;
		wd->alt = NULL;
		wd->next = NULL;
		kw->text = wd;
	    }
	    para->kwtext = kw->text;
	}
    }
}