/*
    picoweb / litheweb -- a web server and application framework
                          for resource constraint systems.

    Copyright (C) 2012 - 2014 Wolfgang Draxinger

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 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 General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#pragma once
#ifndef PICOHTTP_H_HEADERGUARD
#define PICOHTTP_H_HEADERGUARD

#include <stddef.h>
#include <stdint.h>

/* max 70 for boundary + 4 chars for "<CR><LF>--" */
#define PICOHTTP_MULTIPARTBOUNDARY_MAX_LEN 74
#define PICOHTTP_DISPOSITION_NAME_MAX 48

#define PICOHTTP_METHOD_GET  1
#define PICOHTTP_METHOD_HEAD 2
#define PICOHTTP_METHOD_POST 4

#define PICOHTTP_CONTENTTYPE_APPLICATION	0x1000
#define PICOHTTP_CONTENTTYPE_APPLICATION_OCTETSTREAM 0x1000

#define PICOHTTP_CONTENTTYPE_AUDIO		0x2000
#define PICOHTTP_CONTENTTYPE_IMAGE		0x3000
#define PICOHTTP_CONTENTTYPE_MESSAGE		0x4000
#define PICOHTTP_CONTENTTYPE_MODEL		0x5000

#define PICOHTTP_CONTENTTYPE_MULTIPART		0x6000
#define PICOHTTP_CONTENTTYPE_MULTIPART_FORMDATA	0x6004

#define PICOHTTP_CONTENTTYPE_TEXT		0x7000
#define PICOHTTP_CONTENTTYPE_TEXT_CSV		0x7003
#define PICOHTTP_CONTENTTYPE_TEXT_HTML		0x7004
#define PICOHTTP_CONTENTTYPE_TEXT_PLAIN		0x7006

#define PICOHTTP_CONTENTTYPE_VIDEO		0x8000

#define PICOHTTP_CODING_IDENTITY 0
#define PICOHTTP_CODING_COMPRESS 1
#define PICOHTTP_CODING_DEFLATE  2
#define PICOHTTP_CODING_GZIP     4
#define PICOHTTP_CODING_CHUNKED  8

#define PICOHTTP_STATUS_200_OK 200
#define PICOHTTP_STATUS_400_BAD_REQUEST 400
#define PICOHTTP_STATUS_401_UNAUTHORIZED 401
#define PICOHTTP_STATUS_403_FORBIDDEN 402
#define PICOHTTP_STATUS_404_NOT_FOUND 404
#define PICOHTTP_STATUS_405_METHOD_NOT_ALLOWED 405
#define PICOHTTP_STATUS_414_REQUEST_URI_TOO_LONG 414
#define PICOHTTP_STATUS_500_INTERNAL_SERVER_ERROR 500
#define PICOHTTP_STATUS_501_NOT_IMPLEMENTED 501
#define PICOHTTP_STATUS_505_HTTP_VERSION_NOT_SUPPORTED 505

struct picohttpIoOps {
	int (*read)(size_t /*count*/, void* /*buf*/, void*);
	int (*write)(size_t /*count*/, void const* /*buf*/, void*);
	int (*getch)(void*); // returns negative value on error
	int (*putch)(int, void*);
	int (*flush)(void*);
	void *data;
};

#define picohttpIoWrite(ioops,size,buf) (ioops->write(size, buf, ioops->data))
#define picohttpIoRead(ioops,size,buf)  (ioops->read(size, buf, ioops->data))
#define picohttpIoGetch(ioops)          (ioops->getch(ioops->data))
#define picohttpIoPutch(ioops,c)        (ioops->putch(c, ioops->data))
#define picohttpIoFlush(ioops)          (ioops->flush(ioops->data))

enum picohttpVarType {
	PICOHTTP_TYPE_UNDEFINED = 0,
	PICOHTTP_TYPE_INTEGER = 1,
	PICOHTTP_TYPE_REAL = 2,
	PICOHTTP_TYPE_BOOLEAN = 3,
	PICOHTTP_TYPE_TEXT = 4
};

struct picohttpVarSpec {
	char const * const name;
	enum picohttpVarType type;
	size_t max_len;
};

struct picohttpVar {
	struct picohttpVarSpec const *spec;
	union {
		char *text;
		float real;
		int integer;
		uint8_t boolean;
	} value;
	struct picohttpVar *next;
};

struct picohttpRequest;

typedef void (*picohttpHandler)(struct picohttpRequest*);

struct picohttpURLRoute {
	char const * urlhead;
	struct picohttpVarSpec const * get_vars;
	picohttpHandler handler;
	unsigned int max_urltail_len;
	int allowed_methods;
};

#define PICOHTTP_EPOCH_YEAR 1970

struct picohttpDateTime {
	unsigned int Y:7; /* EPOCH + 127 years */
	unsigned int M:4;
	unsigned int D:5;
	unsigned int h:5;
	unsigned int m:6;
	unsigned int s:5; /* seconds / 2 */
};

struct picohttpAuthData {
	size_t const username_maxlen;
	char  * const username;

	size_t const realm_maxlen;
	char* const realm;

	/* Basic auth password or Digest auth response */
	size_t const pwresponse_maxlen;
	char * const pwresponse;

#if 0
	size_t const uri_maxlen;
	char * const uri;
#endif

	unsigned int message_qop;
	uint32_t nonce_count;
};

struct picohttpRequest {
	struct picohttpIoOps const * ioops;
	struct picohttpURLRoute const * route;
	struct picohttpVar *get_vars;
	char *url;
	char *urltail;
	int status;
	int method;
	struct {
		uint8_t major;
		uint8_t minor;
	} httpversion;
	struct {
		int contenttype;
		size_t contentlength;
		uint8_t contentencoding;
		uint8_t transferencoding;
		char multipartboundary[PICOHTTP_MULTIPARTBOUNDARY_MAX_LEN+1];
		size_t chunklength;
		struct picohttpAuthData *auth;
	} query;
	struct {
		char const *contenttype;
		char const *disposition;
		char const *www_authenticate;
		struct picohttpDateTime lastmodified;
		int max_age;
		size_t contentlength;
		uint8_t contentencoding;
		uint8_t transferencoding;
	} response;
	size_t received_octets;
	struct {
		size_t octets;
		uint8_t header;
	} sent;
	void *userdata;
};

struct picohttpMultipart {
	struct picohttpRequest *req;
	uint8_t finished;
	int contenttype;
	struct {
		char name[PICOHTTP_DISPOSITION_NAME_MAX+1];
	} disposition;
	int in_boundary;
	int replay;
	int replayhead;
	int mismatch;
};

typedef void (*picohttpHeaderFieldCallback)(
	void * const data,
	char const *headername,
	char const *headervalue);

size_t picohttpRoutesMaxUrlLength(
	struct picohttpURLRoute const * const routes );

void picohttpProcessRequest(
	struct picohttpIoOps const * const ioops,
	struct picohttpURLRoute const * const routes,
	struct picohttpAuthData * const authdata,
	void *userdata );

void picohttpStatusResponse(
	struct picohttpRequest *req, int status );

void picohttpAuthRequired(
	struct picohttpRequest *req,
	char const * const realm );


int picohttpResponseSendHeader (
	struct picohttpRequest * const req );

int picohttpResponseWrite (
	struct picohttpRequest * const req,
	size_t len,
	void const *buf );

int picohttpGetch(struct picohttpRequest * const req);

struct picohttpMultipart picohttpMultipartStart(
	struct picohttpRequest * const req);

int picohttpMultipartNext(
	struct picohttpMultipart * const mp);

int picohttpMultipartGetch(
	struct picohttpMultipart * const mp);

int picohttpMultipartRead(
	struct picohttpMultipart * const mp,
	size_t len,
	char * const buf);

#endif/*PICOHTTP_H_HEADERGUARD*/