#include <errno.h>
#include <ctype.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#if HAVE_ALLOCA_H
# include <alloca.h>
#endif

#include "findme.h"
#include "popt.h"
#include "poptint.h"

#ifndef HAVE_STRERROR
static char * strerror(int errno) {
    extern int sys_nerr;
    extern char * sys_errlist[];

    if ((0 <= errno) && (errno < sys_nerr))
	return sys_errlist[errno];
    else
	return "unknown errno";
}
#endif

void poptSetExecPath(poptContext con, const char * path, int allowAbsolute) {
    if (con->execPath) free(con->execPath);
    con->execPath = strdup(path);
    con->execAbsolute = allowAbsolute;
}

poptContext poptGetContext(char * name, int argc, char ** argv, 
			   const struct poptOption * options, int flags) {
    poptContext con = malloc(sizeof(*con));

    memset(con, 0, sizeof(*con));

    con->os = con->optionStack;
    con->os->argc = argc;
    con->os->argv = argv;

    if (!(flags & POPT_CONTEXT_KEEP_FIRST))
	con->os->next = 1;			/* skip argv[0] */

    con->leftovers = malloc(sizeof(char *) * (argc + 1));
    con->options = options;
    con->finalArgv = malloc(sizeof(*con->finalArgv) * (argc * 2));
    con->finalArgvAlloced = argc * 2;
    con->flags = flags;
    con->execAbsolute = 1;

    if (getenv("POSIXLY_CORRECT") || getenv("POSIX_ME_HARDER"))
	con->flags |= POPT_CONTEXT_POSIXMEHARDER;
    
    if (name)
	con->appName = strcpy(malloc(strlen(name) + 1), name);

    return con;
}

void poptResetContext(poptContext con) {
    con->os = con->optionStack;
    con->os->currAlias = NULL;
    con->os->nextCharArg = NULL;
    con->os->nextArg = NULL;
    con->os->next = 1;			/* skip argv[0] */

    con->numLeftovers = 0;
    con->nextLeftover = 0;
    con->restLeftover = 0;
    con->doExec = NULL;
    con->finalArgvCount = 0;
}

/* Only one of longName, shortName may be set at a time */
static int handleExec(poptContext con, char * longName, char shortName) {
    int i;

    i = con->numExecs - 1;
    if (longName) {
	while (i >= 0 && (!con->execs[i].longName ||
	    strcmp(con->execs[i].longName, longName))) i--;
    } else {
	while (i >= 0 &&
	    con->execs[i].shortName != shortName) i--;
    }

    if (i < 0) return 0;

    if (con->flags & POPT_CONTEXT_NO_EXEC)
	return 1;

    if (!con->doExec) {
	con->doExec = con->execs + i;
	return 1;
    }

    /* We already have an exec to do; remember this option for next
       time 'round */
    if ((con->finalArgvCount + 1) >= (con->finalArgvAlloced)) {
	con->finalArgvAlloced += 10;
	con->finalArgv = realloc(con->finalArgv,
			sizeof(*con->finalArgv) * con->finalArgvAlloced);
    }

    i = con->finalArgvCount++;
    con->finalArgv[i] = malloc((longName ? strlen(longName) : 0) + 3);
    if (longName)
	sprintf(con->finalArgv[i], "--%s", longName);
    else 
	sprintf(con->finalArgv[i], "-%c", shortName);

    return 1;
}

/* Only one of longName, shortName may be set at a time */
static int handleAlias(poptContext con, char * longName, char shortName,
		       char * nextCharArg) {
    int i;

    if (con->os->currAlias && con->os->currAlias->longName && longName &&
	!strcmp(con->os->currAlias->longName, longName)) 
	return 0;
    if (con->os->currAlias && shortName == con->os->currAlias->shortName)
	return 0;

    i = con->numAliases - 1;
    if (longName) {
	while (i >= 0 && (!con->aliases[i].longName ||
	    strcmp(con->aliases[i].longName, longName))) i--;
    } else {
	while (i >= 0 &&
	    con->aliases[i].shortName != shortName) i--;
    }

    if (i < 0) return 0;

    if ((con->os - con->optionStack + 1) 
	    == POPT_OPTION_DEPTH)
	return POPT_ERROR_OPTSTOODEEP;

    if (nextCharArg && *nextCharArg)
	con->os->nextCharArg = nextCharArg;

    con->os++;
    con->os->next = 0;
    con->os->stuffed = 0;
    con->os->nextArg = con->os->nextCharArg = NULL;
    con->os->currAlias = con->aliases + i;
    con->os->argc = con->os->currAlias->argc;
    con->os->argv = con->os->currAlias->argv;

    return 1;
}

static void execCommand(poptContext con) {
    char ** argv;
    int pos = 0;
    char * script = con->doExec->script;

    argv = malloc(sizeof(*argv) * 
			(6 + con->numLeftovers + con->finalArgvCount));

    if (!con->execAbsolute && strchr(script, '/')) return;

    if (!strchr(script, '/') && con->execPath) {
	argv[pos] = alloca(strlen(con->execPath) + strlen(script) + 2);
	sprintf(argv[pos], "%s/%s", con->execPath, script);
    } else {
	argv[pos] = script;
    }
    pos++;

    argv[pos] = findProgramPath(con->os->argv[0]);
    if (argv[pos]) pos++;
    argv[pos++] = ";";

    memcpy(argv + pos, con->finalArgv, sizeof(*argv) * con->finalArgvCount);
    pos += con->finalArgvCount;

    if (con->numLeftovers) {
	argv[pos++] = "--";
	memcpy(argv + pos, con->leftovers, sizeof(*argv) * con->numLeftovers);
	pos += con->numLeftovers;
    }

    argv[pos++] = NULL;

#ifdef __hpux
    setresuid(getuid(), getuid(),-1);
#else
    setreuid(getuid(), getuid()); /*hlauer: not portable to hpux9.01 */
#endif

    execvp(argv[0], argv);
}

static const struct poptOption * findOption(const struct poptOption * table,
					    const char * longName,
					    const char shortName,
					    poptCallbackType * callback,
					    void ** callbackData) {
    const struct poptOption * opt = table;
    const struct poptOption * opt2;
    const struct poptOption * cb = NULL;

    while (opt->longName || opt->shortName || opt->arg) {
	if (opt->argInfo == POPT_ARG_INCLUDE_TABLE) {
	    opt2 = findOption(opt->arg, longName, shortName, callback, 
			      callbackData);
	    if (opt2) return opt2;
	} else if (opt->argInfo == POPT_ARG_CALLBACK) {
	    cb = opt;
	} else if (longName && opt->longName && 
		   !strcmp(longName, opt->longName)) {
	    break;
	} else if (shortName && shortName == opt->shortName) {
	    break;
	}
	opt++;
    }

    if (!opt->longName && !opt->shortName) return NULL;
    if (cb) {
	*callback = cb->arg;
	*callbackData = cb->descrip;
    } else {
	*callback = NULL;
    }

    return opt;
}

/* returns 'val' element, -1 on last item, POPT_ERROR_* on error */
int poptGetNextOpt(poptContext con) {
    char * optString, * chptr, * localOptString;
    char * longArg = NULL;
    char * origOptString;
    long aLong;
    char * end;
    const struct poptOption * opt = NULL;
    int done = 0;
    int i;
    poptCallbackType cb;
    void * cbData;

    while (!done) {
	while (!con->os->nextCharArg && con->os->next == con->os->argc 
		&& con->os > con->optionStack)
	    con->os--;
	if (!con->os->nextCharArg && con->os->next == con->os->argc) {
	    if (con->doExec) execCommand(con);
	    return -1;
	}

	if (!con->os->nextCharArg) {
		
	    origOptString = con->os->argv[con->os->next++];

	    if (con->restLeftover || *origOptString != '-') {
		con->leftovers[con->numLeftovers++] = origOptString;
		if (con->flags & POPT_CONTEXT_POSIXMEHARDER)
		    con->restLeftover = 1;
		continue;
	    }

	    /* Make a copy we can hack at */
	    localOptString = optString = 
			strcpy(alloca(strlen(origOptString) + 1), 
			origOptString);

	    if (!optString[0])
		return POPT_ERROR_BADOPT;

	    if (optString[1] == '-' && !optString[2]) {
		con->restLeftover = 1;
		continue;
	    } else if (optString[1] == '-') {
		optString += 2;

		if (handleAlias(con, optString, '\0', NULL))
		    continue;
		if (handleExec(con, optString, '\0'))
		    continue;

		chptr = optString;
		while (*chptr && *chptr != '=') chptr++;
		if (*chptr == '=') {
		    longArg = origOptString + (chptr - localOptString) + 1;
		    *chptr = '\0';
		}

		opt = findOption(con->options, optString, '\0', &cb, &cbData);
		if (!opt) return POPT_ERROR_BADOPT;
	    } else 
		con->os->nextCharArg = origOptString + 1;
	}

	if (con->os->nextCharArg) {
	    origOptString = con->os->nextCharArg;

	    con->os->nextCharArg = NULL;

	    if (handleAlias(con, NULL, *origOptString,
			    origOptString + 1)) {
		origOptString++;
		continue;
	    }
	    if (handleExec(con, NULL, *origOptString))
		continue;

	    opt = findOption(con->options, NULL, *origOptString, &cb, &cbData);
	    if (!opt) return POPT_ERROR_BADOPT;

	    origOptString++;
	    if (*origOptString)
		con->os->nextCharArg = origOptString;
	}

	if (opt->arg && opt->argInfo == POPT_ARG_NONE) 
	    *((int *)opt->arg) = 1;
	else if (opt->argInfo != POPT_ARG_NONE) {
	    if (longArg) {
		con->os->nextArg = longArg;
	    } else if (con->os->nextCharArg) {
		con->os->nextArg = con->os->nextCharArg;
		con->os->nextCharArg = NULL;
	    } else { 
		while (con->os->next == con->os->argc && 
		       con->os > con->optionStack)
		    con->os--;
		if (con->os->next == con->os->argc)
		    return POPT_ERROR_NOARG;

		con->os->nextArg = con->os->argv[con->os->next++];
	    }

	    if (opt->arg) {
		switch (opt->argInfo) {
		  case POPT_ARG_STRING:
		    *((char **) opt->arg) = con->os->nextArg;
		    break;

		  case POPT_ARG_INT:
		  case POPT_ARG_LONG:
		    aLong = strtol(con->os->nextArg, &end, 0);
		    if (*end) 
			return POPT_ERROR_BADNUMBER;

		    if (aLong == LONG_MIN || aLong == LONG_MAX)
			return POPT_ERROR_OVERFLOW;
		    if (opt->argInfo == POPT_ARG_LONG) {
			*((long *) opt->arg) = aLong;
		    } else {
			if (aLong > INT_MAX || aLong < INT_MIN)
			    return POPT_ERROR_OVERFLOW;
			*((int *) opt->arg) =aLong;
		    }
		    break;

		  default:
		    printf("option type not implemented in popt\n");
		    exit(1);
		}
	    }
	}

	if (cb)
	    cb(con, opt->val, con->os->nextArg, cbData);
	else if (opt->val) 
	    done = 1;

	if ((con->finalArgvCount + 2) >= (con->finalArgvAlloced)) {
	    con->finalArgvAlloced += 10;
	    con->finalArgv = realloc(con->finalArgv,
			    sizeof(*con->finalArgv) * con->finalArgvAlloced);
	}

	i = con->finalArgvCount++;
	con->finalArgv[i] = 
		malloc((opt->longName ? strlen(opt->longName) : 0) + 3);
	if (opt->longName)
	    sprintf(con->finalArgv[i], "--%s", opt->longName);
	else 
	    sprintf(con->finalArgv[i], "-%c", opt->shortName);

	if (opt->arg && opt->argInfo != POPT_ARG_NONE) 
	    con->finalArgv[con->finalArgvCount++] = strdup(con->os->nextArg);
    }

    return opt->val;
}

char * poptGetOptArg(poptContext con) {
    char * ret = con->os->nextArg;
    con->os->nextArg = NULL;
    return ret;
}

char * poptGetArg(poptContext con) {
    if (con->numLeftovers == con->nextLeftover) return NULL;
    return (con->leftovers[con->nextLeftover++]);
}

char * poptPeekArg(poptContext con) {
    if (con->numLeftovers == con->nextLeftover) return NULL;
    return (con->leftovers[con->nextLeftover]);
}

char ** poptGetArgs(poptContext con) {
    if (con->numLeftovers == con->nextLeftover) return NULL;

    /* some apps like [like RPM ;-) ] need this NULL terminated */
    con->leftovers[con->numLeftovers] = NULL;

    return (con->leftovers + con->nextLeftover);
}

void poptFreeContext(poptContext con) {
    int i;

    for (i = 0; i < con->numAliases; i++) {
	if (con->aliases[i].longName) free(con->aliases[i].longName);
	free(con->aliases[i].argv);
    }

    for (i = 0; i < con->numExecs; i++) {
	if (con->execs[i].longName) free(con->execs[i].longName);
	free(con->execs[i].script);
    }

    for (i = 0; i < con->finalArgvCount; i++)
	free(con->finalArgv[i]);

    free(con->leftovers);
    free(con->finalArgv);
    if (con->appName) free(con->appName);
    if (con->aliases) free(con->aliases);
    if (con->otherHelp) free(con->otherHelp);
    free(con);
}

int poptAddAlias(poptContext con, struct poptAlias newAlias, int flags) {
    int aliasNum = con->numAliases++;
    struct poptAlias * alias;

    /* SunOS won't realloc(NULL, ...) */
    if (!con->aliases)
	con->aliases = malloc(sizeof(newAlias) * con->numAliases);
    else
	con->aliases = realloc(con->aliases, 
			       sizeof(newAlias) * con->numAliases);
    alias = con->aliases + aliasNum;
    
    *alias = newAlias;
    if (alias->longName)
	alias->longName = strcpy(malloc(strlen(alias->longName) + 1), 
				    alias->longName);
    else
	alias->longName = NULL;

    return 0;
}

char * poptBadOption(poptContext con, int flags) {
    struct optionStackEntry * os;

    if (flags & POPT_BADOPTION_NOALIAS)
	os = con->optionStack;
    else
	os = con->os;

    return os->argv[os->next - 1];
}

#define POPT_ERROR_NOARG	-10
#define POPT_ERROR_BADOPT	-11
#define POPT_ERROR_OPTSTOODEEP	-13
#define POPT_ERROR_BADQUOTE	-15	/* only from poptParseArgString() */
#define POPT_ERROR_ERRNO	-16	/* only from poptParseArgString() */

const char * poptStrerror(const int error) {
    switch (error) {
      case POPT_ERROR_NOARG:
	return "missing argument";
      case POPT_ERROR_BADOPT:
	return "unknown option";
      case POPT_ERROR_OPTSTOODEEP:
	return "aliases nested too deeply";
      case POPT_ERROR_BADQUOTE:
	return "error in paramter quoting";
      case POPT_ERROR_BADNUMBER:
	return "invalid numeric value";
      case POPT_ERROR_OVERFLOW:
	return "number too large or too small";
      case POPT_ERROR_ERRNO:
	return strerror(errno);
      default:
	return "unknown error";
    }
}

int poptStuffArgs(poptContext con, char ** argv) {
    int i;

    if ((con->os - con->optionStack) == POPT_OPTION_DEPTH)
	return POPT_ERROR_OPTSTOODEEP;

    for (i = 0; argv[i]; i++);

    con->os++;
    con->os->next = 0;
    con->os->nextArg = con->os->nextCharArg = NULL;
    con->os->currAlias = NULL;
    con->os->argc = i;
    con->os->argv = argv;
    con->os->stuffed = 1;

    return 0;
}