/* the Music Player Daemon (MPD)
 * (c)2003-2006 by Warren Dukes (warren.dukes@gmail.com)
 * This project's homepage is: http://www.musicpd.org
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "conf.h"

#include "log.h"

#include "utils.h"
#include "buffer2array.h"
#include "list.h"

#include <sys/param.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>
#include <errno.h>

#define MAX_STRING_SIZE	MAXPATHLEN+80

#define CONF_COMMENT		'#'
#define CONF_BLOCK_BEGIN	"{"
#define CONF_BLOCK_END		"}"

#define CONF_REPEATABLE_MASK	0x01
#define CONF_BLOCK_MASK		0x02

typedef struct _configEntry {
	unsigned char mask;
	List * configParamList;
} ConfigEntry;

static List * configEntriesList = NULL;

static ConfigParam * newConfigParam(char * value, int line) {
	ConfigParam * ret = malloc(sizeof(ConfigParam));

	if(!value) ret->value = NULL;
	else ret->value = strdup(value);

	ret->line = line;

	ret->numberOfBlockParams = 0;
	ret->blockParams = NULL;

	return ret;
}

static void freeConfigParam(ConfigParam * param) {
	int i;

	if(param->value) free(param->value);

	for(i=0; i<param->numberOfBlockParams; i++) {
		if(param->blockParams[i].name) {
			free(param->blockParams[i].name);
		}
		if(param->blockParams[i].value) {
			free(param->blockParams[i].value);
		}
	}

	if(param->numberOfBlockParams) free(param->blockParams);

	free(param);
}

ConfigEntry * newConfigEntry(int repeatable, int block) {
	ConfigEntry * ret =  malloc(sizeof(ConfigEntry));

	ret->mask = 0;
	ret->configParamList = makeList((ListFreeDataFunc *)freeConfigParam, 1);

	if(repeatable) ret->mask |= CONF_REPEATABLE_MASK;
	if(block) ret->mask |= CONF_BLOCK_MASK;

	return ret;
}

void freeConfigEntry(ConfigEntry * entry) {
	freeList(entry->configParamList);
	free(entry);
}

static void registerConfigParam(char * name, int repeatable, int block) {
	ConfigEntry * entry;

	if(findInList(configEntriesList, name, NULL)) {
		ERROR("config parameter \"%s\" already registered\n", name);
		exit(EXIT_FAILURE);
	}

	entry = newConfigEntry(repeatable, block);

	insertInList(configEntriesList, name, entry);
}

void finishConf(void) {
	freeList(configEntriesList);
}

void initConf(void) {
	configEntriesList = makeList((ListFreeDataFunc *)freeConfigEntry, 1);

	/* registerConfigParam(name,                   repeatable,  block); */
	registerConfigParam(CONF_PORT, 				0,	0);
	registerConfigParam(CONF_PID_FILE, 			0,	0);
	registerConfigParam(CONF_MUSIC_DIR,			0,	0);
	registerConfigParam(CONF_PLAYLIST_DIR,			0,	0);
	registerConfigParam(CONF_LOG_FILE,			0,	0);
	registerConfigParam(CONF_ERROR_FILE,			0,	0);
	registerConfigParam(CONF_CONN_TIMEOUT,			0,	0);
	registerConfigParam(CONF_MIXER_DEVICE,			0,	0);
	registerConfigParam(CONF_MAX_CONN,			0,	0);
	registerConfigParam(CONF_MAX_PLAYLIST_LENGTH,		0,	0);
	registerConfigParam(CONF_BUFFER_BEFORE_PLAY,		0,	0);
	registerConfigParam(CONF_MAX_COMMAND_LIST_SIZE,		0,	0);
	registerConfigParam(CONF_MAX_OUTPUT_BUFFER_SIZE,	0,	0);
	registerConfigParam(CONF_AUDIO_OUTPUT,			1,	1);
	registerConfigParam(CONF_SAVE_ABSOLUTE_PATHS,		0,	0);
	registerConfigParam(CONF_BIND_TO_ADDRESS,		1,	0);
	registerConfigParam(CONF_MIXER_TYPE,			0,	0);
	registerConfigParam(CONF_STATE_FILE,			0,	0);
	registerConfigParam(CONF_USER,				0,	0);
	registerConfigParam(CONF_DB_FILE,			0,	0);
	registerConfigParam(CONF_LOG_LEVEL,			0,	0);
	registerConfigParam(CONF_MIXER_CONTROL,			0,	0);
	registerConfigParam(CONF_FS_CHARSET,			0,	0);
	registerConfigParam(CONF_PASSWORD,			1,	0);
	registerConfigParam(CONF_DEFAULT_PERMS,			0,	0);
	registerConfigParam(CONF_AUDIO_BUFFER_SIZE,		0,	0);
	registerConfigParam(CONF_REPLAYGAIN,			0,	0);
	registerConfigParam(CONF_AUDIO_OUTPUT_FORMAT,		0,	0);
	registerConfigParam(CONF_HTTP_PROXY_HOST,		0,	0);
	registerConfigParam(CONF_HTTP_PROXY_PORT,		0,	0);
	registerConfigParam(CONF_HTTP_PROXY_USER,		0,	0);
	registerConfigParam(CONF_HTTP_PROXY_PASSWORD,		0,	0);
	registerConfigParam(CONF_HTTP_BUFFER_SIZE,		0,	0);
	registerConfigParam(CONF_HTTP_PREBUFFER_SIZE,		0,	0);
	registerConfigParam(CONF_REPLAYGAIN_PREAMP,		0,	0);
	registerConfigParam(CONF_METADATA_TO_USE,		0,	0);
	registerConfigParam(CONF_ID3V1_ENCODING,                0,      0);
}

static void addBlockParam(ConfigParam * param, char * name, char * value,
		int line) 
{
	param->numberOfBlockParams++;

	param->blockParams = realloc(param->blockParams, 
			param->numberOfBlockParams*sizeof(BlockParam));
	
	param->blockParams[param->numberOfBlockParams-1].name = strdup(name);
	param->blockParams[param->numberOfBlockParams-1].value = strdup(value);
	param->blockParams[param->numberOfBlockParams-1].line = line;
}

static ConfigParam * readConfigBlock(FILE * fp, int * count, char * string) {
	ConfigParam * ret = newConfigParam(NULL, *count);

	char ** array;
	int i;
	int numberOfArgs;
	int argsMinusComment;

	while(myFgets(string, MAX_STRING_SIZE ,fp)) {
		(*count)++;

		numberOfArgs = buffer2array(string, &array);

		for(i=0; i<numberOfArgs; i++) {
			if(array[i][0] == CONF_COMMENT) break;
		}

		argsMinusComment = i;

		if(0 == argsMinusComment) {
			freeArgArray(array, numberOfArgs);
			continue;
		}

		if(1 == argsMinusComment && 
				0 == strcmp(array[0], CONF_BLOCK_END))
		{
			freeArgArray(array, numberOfArgs);
			break;
		}

		if(2 != argsMinusComment) {
			ERROR("improperly formatted config file at line %i:"
					" %s\n", *count, string);
			exit(EXIT_FAILURE);
		}

		if(0 == strcmp(array[0], CONF_BLOCK_BEGIN) ||
				0 == strcmp(array[1], CONF_BLOCK_BEGIN) ||
				0 == strcmp(array[0], CONF_BLOCK_END) ||
				0 == strcmp(array[1], CONF_BLOCK_END))
		{
			ERROR("improperly formatted config file at line %i:"
					" %s\n", count, string);
			ERROR("in block begining at line %i\n", ret->line);
			exit(EXIT_FAILURE);
		}

		addBlockParam(ret, array[0], array[1], *count);

		freeArgArray(array, numberOfArgs);
	}

	return ret;
}

void readConf(char * file) {
	FILE * fp;
	char string[MAX_STRING_SIZE+1];
	char ** array;
	int i;
	int numberOfArgs;
	int argsMinusComment;
	int count = 0;
	ConfigEntry * entry;
	void * voidPtr;
	ConfigParam * param;

	if(!(fp=fopen(file,"r"))) {
		ERROR("problems opening file %s for reading: %s\n", file,
			strerror(errno));
		exit(EXIT_FAILURE);
	}

	while(myFgets(string, MAX_STRING_SIZE, fp)) {
		count++;

		numberOfArgs = buffer2array(string, &array);

		for(i=0; i<numberOfArgs; i++) {
			if(array[i][0] == CONF_COMMENT) break;
		}

		argsMinusComment = i;

		if(0 == argsMinusComment) {
			freeArgArray(array, numberOfArgs);
			continue;
		}

		if(2 != argsMinusComment) {
			ERROR("improperly formatted config file at line %i:"
					" %s\n", count, string);
			exit(EXIT_FAILURE);
		}

		if(!findInList(configEntriesList, array[0], &voidPtr)) {
			ERROR("unrecognized parameter in config file at line "
					"%i: %s\n", count, string);
			exit(EXIT_FAILURE);
		}

		entry = (ConfigEntry *) voidPtr;

		if( !(entry->mask & CONF_REPEATABLE_MASK) &&
			entry->configParamList->numberOfNodes)
		{
			param = entry->configParamList->firstNode->data;
			ERROR("config parameter \"%s\" is first defined on line "
					"%i and redefined on line %i\n",
					array[0], param->line, count);
			exit(EXIT_FAILURE);
		}

		if(entry->mask & CONF_BLOCK_MASK) {
			if(0 != strcmp(array[1], CONF_BLOCK_BEGIN)) {
				ERROR("improperly formatted config file at "
					"line %i: %s\n", count, string);
				exit(EXIT_FAILURE);
			}
			param = readConfigBlock(fp, &count, string);
		}
		else param = newConfigParam(array[1], count);

		insertInListWithoutKey(entry->configParamList, param);

		freeArgArray(array, numberOfArgs);
	}
	fclose(fp);
}

ConfigParam * getNextConfigParam(char * name, ConfigParam * last) {
	void * voidPtr;
	ConfigEntry * entry;
	ListNode * node;
	ConfigParam * param;

	if(!findInList(configEntriesList, name, &voidPtr)) return NULL;

	entry = voidPtr;

	node = entry->configParamList->firstNode;

	if(last) {
		while(node!=NULL) {
			param = node->data;
			node = node->nextNode;
			if(param == last) break;
		}
	}

	if(node == NULL)  return NULL;

	param = node->data;

	return param;
}

char * getConfigParamValue(char * name) {
	ConfigParam * param = getConfigParam(name);

	if(!param) return NULL;

	return param->value;
}

BlockParam * getBlockParam(ConfigParam * param, char * name) {
	BlockParam * ret = NULL;
	int i;

	for(i = 0; i < param->numberOfBlockParams; i++) {
		if(0 == strcmp(name, param->blockParams[i].name)) {
			if(ret) {
				ERROR("\"%s\" first defined on line %i, and "
					"redefined on line %i\n", name, 
					ret->line, param->blockParams[i].line);
			}
			ret = param->blockParams+i;
		}
	}

	return ret;
}

ConfigParam * parseConfigFilePath(char * name, int force) {
	ConfigParam * param = getConfigParam(name);
	char * path;

	if(!param && force) {
		ERROR("config parameter \"%s\" not found\n", name);
		exit(EXIT_FAILURE);
	}

	if(!param) return NULL;

	path = param->value;

	if(path[0] != '/' && path[0] != '~') {
		ERROR("\"%s\" is not an absolute path at line %i\n",
				param->value, param->line);
		exit(EXIT_FAILURE);
	}
	/* Parse ~ in path */
	else if(path[0] == '~') {
		struct passwd * pwd = NULL;
		char * newPath;
		int pos = 1;
		if(path[1]=='/' || path[1] == '\0') {
			ConfigParam * userParam = getConfigParam(CONF_USER);

			if(userParam) {
				pwd = getpwnam(userParam->value);
				if(!pwd) {
					ERROR("no such user %s at line %i\n",
							userParam->value, 
							userParam->line);
					exit(EXIT_FAILURE);
				}
			}
			else {
				uid_t uid = geteuid();
				if((pwd = getpwuid(uid)) == NULL) {
					ERROR("problems getting passwd entry "
							"for current user\n");
					exit(EXIT_FAILURE);
				}
			}
		}
		else {
			int foundSlash = 0;
			char * ch = path+1;
			for(;*ch!='\0' && *ch!='/';ch++);
			if(*ch=='/') foundSlash = 1;
			* ch = '\0';
			pos+= ch-path-1;
			if((pwd = getpwnam(path+1)) == NULL) {
				ERROR("user \"%s\" not found at line %i\n",
						path+1, param->line);
				exit(EXIT_FAILURE);
			}
			if(foundSlash) *ch = '/';
		}
		newPath = malloc(strlen(pwd->pw_dir)+strlen(path+pos)+1);
		strcpy(newPath, pwd->pw_dir);
		strcat(newPath, path+pos);
		free(param->value);
		param->value = newPath;
	}

	return param;
}