/* Copyright (C) 2020  C. McEnroe <june@causal.agency>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <err.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <sys/types.h>
#include <sysexits.h>

#include <kcgi.h>
#include <kcgihtml.h>
#include <sqlite3.h>

// Why does it return (const unsigned char *)?
#define sqlite3_column_text(...) (const char *)sqlite3_column_text(__VA_ARGS__)

#define SQL(...) #__VA_ARGS__

#define ENUM_PAGES \
	X("networks", Networks) \
	X("contexts", Contexts) \
	X("events", Events) \
	X("search", Search) \
	X("stylesheet", Stylesheet)

extern const char *CSS;

enum {
#define X(path, page) page,
	ENUM_PAGES
#undef X
	PagesLen,
};
extern const char *Pages[PagesLen];

#define ENUM_KEYS \
	X(kvalid_stringne, "network", Network) \
	X(kvalid_stringne, "context", Context) \
	X(kvalid_stringne, "before", Before) \
	X(kvalid_stringne, "after", After) \
	X(kvalid_stringne, "query", Query) \
	X(kvalid_int, "offset", Offset) \
	X(kvalid_int, "tidy", Tidy) \
	X(NULL, "export", Export)

enum Key {
#define X(valid, name, key) key,
	ENUM_KEYS
#undef X
	KeysLen,
};
extern const struct kvalid Keys[KeysLen];

extern int contextsRecent;
extern bool contextsPublic;
extern const char *NetworksQuery;
extern const char *ContextsQuery;
extern const char *ContextsMOTDQuery;
enum kcgi_err networksPage(struct kreq *req);
enum kcgi_err contextsPage(struct kreq *req);

extern int eventsGap;
extern int eventsOverlap;
extern int eventsLimit;
extern const char *EventsTopicQuery;
extern const char *EventsAfterQuery;
extern const char *EventsBeforeQuery;
extern const char *SearchQuery;
enum kcgi_err eventsPage(struct kreq *req);
enum kcgi_err searchPage(struct kreq *req);

extern sqlite3 *db;

#define ENUM_STMTS \
	X(networks, NetworksQuery) \
	X(contexts, ContextsQuery) \
	X(motd, ContextsMOTDQuery) \
	X(topic, EventsTopicQuery) \
	X(eventsAfter, EventsAfterQuery) \
	X(eventsBefore, EventsBeforeQuery) \
	X(search, SearchQuery)

extern struct Statements {
#define X(name, query) sqlite3_stmt *name;
	ENUM_STMTS
#undef X
} stmt;

static inline void dbPrepare(sqlite3_stmt **stmt, const char *query) {
	int error = sqlite3_prepare_v3(
		db, query, -1, SQLITE_PREPARE_PERSISTENT, stmt, NULL
	);
	if (error) errx(EX_SOFTWARE, "%s: %s", sqlite3_errmsg(db), query);
}

static inline int dbParam(sqlite3_stmt *stmt, const char *param) {
	int index = sqlite3_bind_parameter_index(stmt, param);
	if (index) return index;
	errx(EX_SOFTWARE, "no such parameter %s: %s", param, sqlite3_sql(stmt));
}

static inline void
dbBindInt(sqlite3_stmt *stmt, const char *param, sqlite3_int64 value) {
	if (!sqlite3_bind_int64(stmt, dbParam(stmt, param), value)) return;
	errx(EX_SOFTWARE, "sqlite3_bind_int64: %s", sqlite3_errmsg(db));
}

static inline void
dbBindText(sqlite3_stmt *stmt, const char *param, const char *value) {
	if (!sqlite3_bind_text(stmt, dbParam(stmt, param), value, -1, NULL)) return;
	errx(EX_SOFTWARE, "sqlite3_bind_text: %s", sqlite3_errmsg(db));
}

enum {
	DatabaseVersionMin = 4,
	DatabaseVersionMax = 5,
};

#define ENUM_TYPE \
	X(Privmsg, "privmsg") \
	X(Notice, "notice") \
	X(Action, "action") \
	X(Join, "join") \
	X(Part, "part") \
	X(Quit, "quit") \
	X(Kick, "kick") \
	X(Nick, "nick") \
	X(Topic, "topic") \
	X(Ban, "ban") \
	X(Unban, "unban")

enum Type {
#define X(id, name) id,
	ENUM_TYPE
#undef X
	TypesLen,
};

struct Event {
	int64_t event;
	time_t time;
	const char *network;
	const char *context;
	enum Type type;
	const char *nick;
	const char *user;
	const char *host;
	const char *target;
	const char *message;
};

extern bool htmlHideHost;
extern const char *htmlStylesheet;
enum kcgi_err htmlHead(
	struct khtmlreq *html, struct kreq *req, const char *title
);
enum kcgi_err htmlHidden(struct khtmlreq *html, struct kreq *req, enum Key key);
enum kcgi_err htmlNav(struct khtmlreq *html, struct kreq *req);
enum kcgi_err htmlIRC(struct khtmlreq *html, const char *str);
enum kcgi_err htmlEvent(
	struct khtmlreq *html, struct kreq *req, struct Event *event
);
enum kcgi_err htmlFooter(struct khtmlreq *html, struct kreq *req);

static inline enum kcgi_err
httpHead(struct kreq *req, enum khttp http, enum kmime mime) {
	enum kcgi_err error = 0
		|| khttp_head(req, kresps[KRESP_STATUS], "%s", khttps[http])
		|| khttp_head(req, kresps[KRESP_CONTENT_TYPE], "%s", kmimetypes[mime]);
	if (req->fieldmap[Export]) {
		error = error || khttp_head(
			req, kresps[KRESP_CONTENT_DISPOSITION],
			"attachment; filename=\"%s.%s\"", req->pagename, ksuffixes[mime]
		);
	}
	return error;
}

static inline enum kcgi_err
httpRedirect(struct kreq *req, const char *url) {
	return httpHead(req, KHTTP_302, KMIME_TEXT_PLAIN)
		|| khttp_head(req, kresps[KRESP_LOCATION], "%s", url)
		|| khttp_body(req)
		|| khttp_printf(req, "%s\n", url);
}

static inline enum kcgi_err httpFail(struct kreq *req, enum khttp http) {
	return httpHead(req, http, KMIME_TEXT_PLAIN)
		|| khttp_body(req)
		|| khttp_printf(req, "%s\n", khttps[http]);
}