#include <u.h>
#include <libc.h>
#include <bio.h>
#include <auth.h>
#include <libsec.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
#include "cvsfs.h"

typedef struct {
	Ent *ent;
	Rev *rev;
} Log;

/* Sort order designed for simplest changelog contents */
static int
logcomp(void *a, void *b)
{
	int d;
	Log *la = a;
	Log *lb = b;

	if (labs(la->rev->mtime - lb->rev->mtime) > ATOMIC)
		return la->rev->mtime - lb->rev->mtime;
	if ((d = strcmp(la->rev->author, lb->rev->author)))
		return d;
	if ((d = strcmp(la->rev->desc, lb->rev->desc)))
		return d;
	if ((d = strcmp(la->ent->path, lb->ent->path)))
		return d;
	return 0;
}

static int
mklog(Sess *s, Log **log)
{
	Ent *e;
	Rev *r;
	Log *l;
	int nlog;

	nlog = 0;
	for (e = s->ents; e < s->ents+s->nents; e++)
		for (r = e->revs; r; r = r->next)
			nlog++;

	*log = emalloc9p(nlog * sizeof(Log));

	l = *log;
	for (e = s->ents; e < s->ents+s->nents; e++)
		for (r = e->revs; r; r = r->next){
			l->ent = e;
			l->rev = r;
			l++;
		}

	qsort(*log, nlog, sizeof(Log), logcomp);

	return nlog;
}


char *
changelog(Sess *s)
{
	Fmt f;
	Tm *tp;
	int nlog;
	long omtime;
	Log *log, *l;
	char *p, *op, *opath, *path, *oauthor, *odesc, *chglog;
	char *months[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };

	omtime = 0;
	oauthor = "";
	odesc = "";
	op = opath = "";

	nlog = mklog(s, &log);

	fmtstrinit(&f);
	for (l = log; l < log+nlog; l++){
		if (strcmp(l->rev->desc, odesc) != 0 ||
		    strcmp(l->rev->author, oauthor) != 0 ||
		    labs(l->rev->mtime - omtime) > 60){
			tp = localtime(l->rev->mtime);
			fmtprint(&f, "\n");
			fmtprint(&f, "%d/%s/%d %02d:%02d:%02d  %s\n",
				tp->mday, months[tp->mon], tp->year+1900,
				tp->hour, tp->min, tp->sec, l->rev->author);
			fmtprint(&f, "%s", l->rev->desc);
			op = opath = "";
		}

		path = l->ent->path;
		assert((p = strrchr(path, '/')) != nil);
		if (p-path != op-opath || strncmp(path, opath, p-path) != 0)
			fmtprint(&f, "\t%.*s/...\n", (int)(p-path), path);
		fmtprint(&f, "\t\t%-32s  ", p+1);

		fmtprint(&f, "%s ", l->rev->rev);

		if (l->rev->added || l->rev->removed)
			fmtprint(&f, "+%d-%d ", l->rev->added, l->rev->removed);

		if (strcmp(l->ent->keysub, "key-val") != 0)
			fmtprint(&f, "%s ", l->ent->keysub);

		if (l->rev->locker)
			fmtprint(&f, "locked-by=%s ", l->rev->locker);

		fmtprint(&f, "\n");

		op = p;
		opath = l->ent->path;
		omtime = l->rev->mtime;
		oauthor = l->rev->author;
		odesc = l->rev->desc;
	}
	chglog = fmtstrflush(&f);
	free(log);
	return chglog;
}