/*
** Copyright (c) 2006 D. Richard Hipp
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public
** License version 2 as published by the Free Software Foundation.
**
** 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 library; if not, write to the
** Free Software Foundation, Inc., 59 Temple Place - Suite 330,
** Boston, MA  02111-1307, USA.
**
** Author contact information:
**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*******************************************************************************
**
** Commands and procedures used for creating, processing, editing, and
** querying information about users.
*/
#include "config.h"
#include "user.h"


/*
** Strip leading and trailing space from a string and add the string
** onto the end of a blob.
*/
static void strip_string(Blob *pBlob, char *z){
  int i;
  blob_reset(pBlob);
  while( isspace(*z) ){ z++; }
  for(i=0; z[i]; i++){
    if( z[i]=='\r' || z[i]=='\n' ){
       while( i>0 && isspace(z[i-1]) ){ i--; }
       z[i] = 0;
       break;
    }
    if( z[i]<' ' ) z[i] = ' ';
  }
  blob_append(pBlob, z, -1);
}

#ifdef __MINGW32__
/*
** getpass for Windows
*/
static char *getpass(const char *prompt){
  static char pwd[64];
  size_t i;

  fputs(prompt,stderr);
  fflush(stderr);
  for(i=0; i<sizeof(pwd)-1; ++i){
    pwd[i] = _getch();
    if(pwd[i]=='\r' || pwd[i]=='\n'){
      break;
    }
    /* BS or DEL */
    else if(i>0 && (pwd[i]==8 || pwd[i]==127)){
      i -= 2;
      continue;
    }
    /* CTRL-C */
    else if(pwd[i]==3) {
      i=0;
      break;
    }
    /* ESC */
    else if(pwd[i]==27){
      i=0;
      break;
    }
    else{
      fputc('*',stderr);
    }
  }
  pwd[i]='\0';
  fputs("\n", stderr);
  return pwd;
}
#endif

/*
** Do a single prompt for a passphrase.  Store the results in the blob.
*/
static void prompt_for_passphrase(const char *zPrompt, Blob *pPassphrase){
  char *z = getpass(zPrompt);
  strip_string(pPassphrase, z);
}

/*
** Prompt the user for a password.  Store the result in the pPassphrase
** blob.
**
** Behavior is controlled by the verify parameter:
**
**     0     Just ask once.
**
**     1     If the first answer is a non-empty string, ask for
**           verification.  Repeat if the two strings do not match.
**
**     2     Ask twice, repeat if the strings do not match.
*/
void prompt_for_password(
  const char *zPrompt,
  Blob *pPassphrase,
  int verify
){
  Blob secondTry;
  blob_zero(pPassphrase);
  blob_zero(&secondTry);
  while(1){
    prompt_for_passphrase(zPrompt, pPassphrase);
    if( verify==0 ) break;
    if( verify==1 && blob_size(pPassphrase)==0 ) break;
    prompt_for_passphrase("Again: ", &secondTry);
    if( blob_compare(pPassphrase, &secondTry) ){
      printf("Passphrases do not match.  Try again...\n");
    }else{
      break;
    }
  }
  blob_reset(&secondTry);
}

/*
** Prompt the user to enter a single line of text.
*/
void prompt_user(const char *zPrompt, Blob *pIn){
  char *z;
  char zLine[1000];
  blob_zero(pIn);
  printf("%s", zPrompt);
  fflush(stdout);
  z = fgets(zLine, sizeof(zLine), stdin);
  if( z ){
    strip_string(pIn, z);
  }
}


/*
** COMMAND:  user
**
** Usage: %fossil user SUBCOMMAND ...  ?-R|--repository FILE?
**
** Run various subcommands on users of the open repository or of
** the repository identified by the -R or --repository option.
**
**    %fossil user capabilities USERNAME ?STRING?
**
**        Query or set the capabilities for user USERNAME
**
**    %fossil user default ?USERNAME?
**
**        Query or set the default user.  The default user is the
**        user for command-line interaction.
**
**    %fossil user list
**
**        List all users known to the repository
**
**    %fossil user new ?USERNAME?
**
**        Create a new user in the repository.  Users can never be
**        deleted.  They can be denied all access but they must continue
**        to exist in the database.
**
**    %fossil user password USERNAME
**
**        Change the web access password for a user.
*/
void user_cmd(void){
  int n;
  db_find_and_open_repository();
  if( g.argc<3 ){
    usage("capabilities|default|list|new|password ...");
  }
  n = strlen(g.argv[2]);
  if( n>=2 && strncmp(g.argv[2],"new",n)==0 ){
    Blob passwd, login, contact;

    if( g.argc>=4 ){
      blob_zero(&login);
      blob_append(&login, g.argv[3], -1);
    }else{
      prompt_user("login: ", &login);
    }
    if( db_exists("SELECT 1 FROM user WHERE login=%B", &login) ){
      fossil_fatal("user %b already exists", &login);
    }
    prompt_user("contact-info: ", &contact);
    prompt_for_password("password: ", &passwd, 1);
    db_multi_exec(
      "INSERT INTO user(login,pw,cap,info)"
      "VALUES(%B,%B,'jnor',%B)",
      &login, &passwd, &contact
    );
  }else if( n>=2 && strncmp(g.argv[2],"default",n)==0 ){
    user_select();
    if( g.argc==3 ){
      printf("%s\n", g.zLogin);
    }else{
      if( !db_exists("SELECT 1 FROM user WHERE login=%Q", g.argv[3]) ){
        fossil_fatal("no such user: %s", g.argv[3]);
      }
      if( g.localOpen ){
        db_lset("default-user", g.argv[3]);
      }else{
        db_set("default-user", g.argv[3], 0);
      }
    }
  }else if( n>=2 && strncmp(g.argv[2],"list",n)==0 ){
    Stmt q;
    db_prepare(&q, "SELECT login, info FROM user ORDER BY login");
    while( db_step(&q)==SQLITE_ROW ){
      printf("%-12s %s\n", db_column_text(&q, 0), db_column_text(&q, 1));
    }
    db_finalize(&q);
  }else if( n>=2 && strncmp(g.argv[2],"password",2)==0 ){
    char *zPrompt;
    int uid;
    Blob pw;
    if( g.argc!=4 ) usage("password USERNAME");
    uid = db_int(0, "SELECT uid FROM user WHERE login=%Q", g.argv[3]);
    if( uid==0 ){
      fossil_fatal("no such user: %s", g.argv[3]);
    }
    zPrompt = mprintf("new passwd for %s: ", g.argv[3]);
    prompt_for_password(zPrompt, &pw, 1);
    if( blob_size(&pw)==0 ){
      printf("password unchanged\n");
    }else{
      db_multi_exec("UPDATE user SET pw=%B WHERE uid=%d", &pw, uid);
    }
  }else if( n>=2 && strncmp(g.argv[2],"capabilities",2)==0 ){
    int uid;
    if( g.argc!=4 && g.argc!=5 ){
      usage("user capabilities USERNAME ?PERMISSIONS?");
    }
    uid = db_int(0, "SELECT uid FROM user WHERE login=%Q", g.argv[3]);
    if( uid==0 ){
      fossil_fatal("no such user: %s", g.argv[3]);
    }
    if( g.argc==5 ){
      db_multi_exec(
        "UPDATE user SET cap=%Q WHERE uid=%d", g.argv[4],
        uid
      );
    }
    printf("%s\n", db_text(0, "SELECT cap FROM user WHERE uid=%d", uid));
  }else{
    fossil_panic("user subcommand should be one of: "
                 "capabilities default list new password");
  }
}

/*
** Attempt to set the user to zLogin
*/
static int attempt_user(const char *zLogin){
  int uid;

  if( zLogin==0 ){
    return 0;
  }
  uid = db_int(0, "SELECT uid FROM user WHERE login=%Q", zLogin);
  if( uid ){
    g.userUid = uid;
    g.zLogin = mprintf("%s", zLogin);
    return 1;
  }
  return 0;
}

/*
** Figure out what user is at the controls.
**
**   (1)  Use the --user and -U command-line options.
**
**   (2)  If the local database is open, check in VVAR.
**
**   (3)  Check the default user in the repository
**
**   (4)  Try the USER environment variable.
**
**   (5)  Use the first user in the USER table.
**
** The user name is stored in g.zLogin.  The uid is in g.userUid.
*/
void user_select(void){
  Stmt s;

  if( g.userUid ) return;
  if( attempt_user(g.zLogin) ) return;

  if( g.localOpen && attempt_user(db_lget("default-user",0)) ) return;

  if( attempt_user(db_get("default-user", 0)) ) return;

  if( attempt_user(getenv("USER")) ) return;

  db_prepare(&s, "SELECT uid, login FROM user"
                 " WHERE login NOT IN ('anonymous','nobody')");
  if( db_step(&s)==SQLITE_ROW ){
    g.userUid = db_column_int(&s, 0);
    g.zLogin = mprintf("%s", db_column_text(&s, 1));
  }
  db_finalize(&s);

  if( g.userUid==0 ){
    db_prepare(&s, "SELECT uid, login FROM user");
    if( db_step(&s)==SQLITE_ROW ){
      g.userUid = db_column_int(&s, 0);
      g.zLogin = mprintf("%s", db_column_text(&s, 1));
    }
    db_finalize(&s);
  }

  if( g.userUid==0 ){
    db_multi_exec(
      "INSERT INTO user(login, pw, cap, info)"
      "VALUES('anonymous', '', 'cfghjkmnoqw', '')"
    );
    g.userUid = db_last_insert_rowid();
    g.zLogin = "anonymous";
  }
}