#include <agar/core.h>
#include <agar/net/web.h>

typedef struct web_application {
	const char *name;			/* Description */
	const char *copyright;			/* Copyright notice */
	const char *availLangs[WEB_LANGS_MAX];	/* Available languages */
	const char *homeOp;			/* Default operation */
	Uint flags;				/* Option flags */
	void (*destroyFn)(void);
	void (*logFn)(enum web_loglvl, const char *s);
	/* ... */
} WEB_Application;

WEB_Application myExampleApp = {
	"ExampleApp",
	"Copyright (c) my name",
	{ "en", "es", "fr", NULL },  /* English, Spanish, French */
	"main_welcome",
	0,		/* flags */
	NULL,		/* destroy */
	NULL		/* log */
};

typedef struct web_module {
	char *name;                     /* Short name */
	char *icon;                     /* Icon (HTML) */
	char *lname;                    /* Long name (HTML) */
	char *desc;                     /* Description (HTML) */
	int  (*init)(void *sess);       /* App initialization */
	void (*destroy)(void);          /* App cleanup */
	int  (*sessOpen)(void *sess);   /* Session opened */
	void (*sessClose)(void *sess);  /* Session closed */
	int (*indexFn)(WEB_Query *q);   /* Default op */
	void (*menu)(WEB_Query *q,      /* Menu override */
	             WEB_Variable *V);
	WEB_MenuSection *menuSections;  /* Menu sections or NULL */
	WEB_Command *commands;          /* Command map */
} WEB_Module;

typedef struct web_command {
	char *name;                         /* Method name */
	int (*fn)(void *mod, WEB_Query *q); /* Function */
	const char *type;                   /* MIME type (or NULL) */
} WEB_Command;

static WEB_Command mymodCommands[] = {
	{ "mymod_hello",	mymod_hello,	"text/html",     "Pi" },
	{ "mymod_image",	mymod_image,	"image/png",     "" },
	{ "mymod_json",		mymod_json,	"[json]",        "" },
	{ "mymod_status",	mymod_status,	"[json-status]", "" },
	{ "mymod_customtype",	mymod_custtype,	NULL,            "" },
	{ NULL,			NULL,		NULL,            "" }
};

{ "code": -1,
  "error": "<text from AG_GetError()>",
  "backend_version": "<agar version>" }

{ "lang": <language code>,
  <extra JSON emitted by function>,
  "code": <return code from function>,
  "error": "<text from AG_GetError() on failure>",
  "backend_version": "<agar version on failure>" }

typedef struct web_cookie {
	char name[WEB_COOKIE_NAME_MAX];      /* Name (RO) */
	char value[WEB_COOKIE_VALUE_MAX];    /* Value */
	char expires[WEB_COOKIE_EXPIRE_MAX]; /* Expiration date */
	char domain[WEB_COOKIE_DOMAIN_MAX];  /* Domain match */
	char path[WEB_COOKIE_PATH_MAX];      /* Path attribute */
	Uint flags;
#define WEB_COOKIE_SECURE 0x01               /* Set Secure attribute */
} WEB_Cookie;

enum web_loglvl {
	WEB_LOG_EMERG,   /* General panic condition */
	WEB_LOG_ALERT,   /* Immediate attention required */
	WEB_LOG_CRIT,    /* Critical conditions, I/O errors */
	WEB_LOG_ERR,     /* General errors */
	WEB_LOG_WARNING, /* Warning messages */
	WEB_LOG_NOTICE,  /* Condition should be handled specially */
	WEB_LOG_INFO,    /* Informational messages */
	WEB_LOG_DEBUG,   /* Debugging information */
	WEB_LOG_QUERY,   /* HTTP query (e.g., GET, POST) parsing */
	WEB_LOG_WORKER,  /* Errors specific to worker processes */
	WEB_LOG_EVENT    /* Errors related to Push events */
};

typedef struct web_variable {
	char	 key[WEB_VAR_NAME_MAX]; /* Name ("\0" = anonymous) */
	char	*value;                 /* Value (C string) */
	AG_Size	 len;                   /* Content length (characters) */
	AG_Size	 bufSize;               /* Buffer size */
	int	 global;                /* Persistent across queries */
	AG_TAILQ_ENTRY(web_variable) vars;
} WEB_Variable;

WEB_VAR_SetS("username", "nobody");
WEB_VAR_SetS("password", "test1234");
WEB_OutputHTML("login_form");
WEB_VAR_Wipe("password");

WEB_VAR *v;
v = WEB_VAR_SetS(NULL, "Hello, ");      /* Anonymous variable */
WEB_VAR_CatS(v, "world!");
WEB_VAR_Free(v);

typedef struct web_session_ops {
	const char *name;             /* Session class name */
	AG_Size size;                 /* Structure size */
	Uint flags;
#define WEB_SESSION_PREFORK_AUTH 0x01 /* Call auth() before fork() */
	time_t sessTimeout;           /* Session inactivity (s) */
	time_t workerTimeout;         /* Worker inactivity (s) */

	void (*init)(void *sess);
	void (*destroy)(void *sess);
	int  (*load)(void *sess, AG_DataSource *);
	void (*save)(void *sess, AG_DataSource *);
	int  (*auth)(void *sess, const char *user, const char *pass);
	WEB_CommandPreAuth preAuthCmds[10];
	int  (*sessOpen)(void *sess, const char *user);
	void (*sessRestored)(void *sess, const char *user);
	void (*sessClose)(void *sess);
	void (*sessExpired)(void *sess);
	void (*beginFrontQuery)(WEB_Query *q, const char *op);
	void (*loginPage)(WEB_Query *q);
	void (*logout)(WEB_Query *q);
	void (*addSelectFDs)(void *sess, fd_set *rd, fd_set *wr, int *max);
	void (*procSelectFDs)(void *sess, fd_set *rd, fd_set *wr);
} WEB_SessionOps;

/* Per session data */
typedef struct mySiteSession {
	struct web_session _inherit;  /* WEB_Session->MySiteSession */
	char username[32];            /* Authenticated username */
	time_t lastLogin;             /* Last login */
	/* ... */
} MySiteSession;

static void
Init(void *pSess)
{
	MySiteSession *S = pSess;
	S->username[0] = '\0';
	S->lastLogin = 0;
}
static void
Load(void *pSess, AG_DataSource *ds)
{
	MySiteSession *S = pSess;
	S->lastLogin = (time_t)AG_ReadUint64(ds);
}
static void
Save(void *pSess, AG_DataSource *ds)
{
	MySiteSession *S = pSess;
	AG_WriteUint64(ds, S->lastLogin);
}
static int
Auth(void *pSess, const char *user, const char *password)
{
	return AuthSuccessful(user, password) ? 0 : -1;
}
static void
AuthRegChallenge(WEB_Query *q)
{
	GenerateCaptchaGif();
	WEB_Write(q, captchaGif, captchaGifSize);
}
static void
AuthRegFinish(WEB_Query *q)
{
	/* Process POSTDATA from registration form and create account */
}
static void
AuthRegConfirm(WEB_Query *q)
{
	/* Complete e-mail or mobile verification */
}
static int
SessOpen(void *pSess, const char *username)
{
	MySiteSession *S = pSess;
	time_t t;

	Strlcpy(S->username, username, sizeof(S->username));
	time(&t);
	S->lastLogin = t;
	WEB_LogInfo("User %s logged in", username);
	return (0);
}
static void
SessRestored(void *pSess, const char *username)
{
	MySiteSession *S = pSess;
	WEB_Session *WS = pSess;

	Strlcpy(S->username, username, sizeof(S->username));
	WEB_LogInfo("User %s recovered session %s", username, WS->id);
}
static void
SessClose(void *pSess)
{
	MySiteSession *S = pSess;
	WEB_LogInfo("User %s logged out", S->username);
}
static void
BeginPreAuthCmd(WEB_Query *q, const char *op)
{
	/* Set common variables for all preAuthCmds[] methods */
	WEB_VAR_SetS("_admin", "webmaster@example.com");
	WEB_VAR_SetS("_user", "");
	WEB_VAR_SetS("_theme", "Default");
	WEB_VAR_SetS("_modules",
	    "<li><a href='/'>Sign in</a></li>"
	    "<li><a href='/register.html'>Create account</a></li>");
}
static void
LoginPage(WEB_Query *q)
{
	const char *user = WEB_Get(q, "username", 32);
	const char *pass = WEB_Get(q, "password", 32);
	const char *op = WEB_Get(q, "op", WEB_OPNAME_MAX);

	WEB_VAR_SetS("login_username", (user) ? user : "");
	WEB_VAR_SetS("op", (op) ? op : "main_index");

	WEB_SetCode(q, "200 OK");
	WEB_SetHeaderS(q, "Vary", "accept-language,Accept-Encoding,"
	                          "User-Agent");
	WEB_SetHeaderS(q, "Last-Modified", q->date);
	WEB_SetHeaderS(q, "Content-Type", "text/html; charset=utf8");
	WEB_SetHeaderS(q, "Content-Language", q->lang);
	WEB_SetHeaderS(q, "Cache-Control", "no-cache, no-store, "
	                                   "must-revalidate");
	WEB_SetHeaderS(q, "Expires", "0");
	WEB_OutputHTML(q, "loginPage");
}
static void
Logout(WEB_Query *q)
{
	WEB_Cookie *ck;

	/* Clear the session ID cookie */
	ck = WEB_SetCookieS(q, "sess", "");
	ck->path[0] = '/';
	ck->path[1] = '\0';

	WEB_OutputHTML(q, "logoutPage");
}

WEB_SessionOps mySiteSessionOps = {
	"My Site's Auth Module",
	sizeof(MySiteSession),
	WEB_SESSION_PREFORK_AUTH, /* Invoke auth() before fork */
	7*24*60*60,               /* Session inactivity timeout (s) */
	1*60,                     /* Worker inactivity timeout (s) */
	Init,
	NULL,                     /* destroy */
	Load,
	Save,
	Auth,
	{
		{ "regChallenge", AuthRegChallenge, "image/gif" },
		{ "regFinish",    AuthRegFinish,    "text/html" },
		{ "regConfirm",   AuthRegConfirm,   "text/html" },
		/*
		 * Declare more methods to handle password recovery
		 * and other administrative functions.
		 */
		{ NULL,           NULL,             NULL        }
	},
	SessOpen,
	SessRestored,
	SessClose,
	NULL,             /* sessExpired */
	BeginPreAuthCmd,
	LoginPage,
	Logout,
	NULL,             /* addSelectFDs */
	NULL              /* procSelectFDs */
};

typedef int (*WEB_EventFilterFn)(char *sessID, char *user,
                                 char *langCode, const void *arg);