/*
** 2017-12-17
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** Utility functions sqlar_compress() and sqlar_uncompress(). Useful
** for working with sqlar archives and used by the shell tool's built-in
** sqlar support.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <zlib.h>

/*
** Implementation of the "sqlar_compress(X)" SQL function.
**
** If the type of X is SQLITE_BLOB, and compressing that blob using
** zlib utility function compress() yields a smaller blob, return the
** compressed blob. Otherwise, return a copy of X.
*/
static void sqlarCompressFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  assert( argc==1 );
  if( sqlite3_value_type(argv[0])==SQLITE_BLOB ){
    const Bytef *pData = sqlite3_value_blob(argv[0]);
    uLong nData = sqlite3_value_bytes(argv[0]);
    uLongf nOut = compressBound(nData);
    Bytef *pOut;

    pOut = (Bytef*)sqlite3_malloc(nOut);
    if( pOut==0 ){
      sqlite3_result_error_nomem(context);
      return;
    }else{
      if( Z_OK!=compress(pOut, &nOut, pData, nData) ){
        sqlite3_result_error(context, "error in compress()", -1);
      }else if( nOut<nData ){
        sqlite3_result_blob(context, pOut, nOut, SQLITE_TRANSIENT);
      }else{
        sqlite3_result_value(context, argv[0]);
      }
      sqlite3_free(pOut);
    }
  }else{
    sqlite3_result_value(context, argv[0]);
  }
}

/*
** Implementation of the "sqlar_uncompress(X,SZ)" SQL function
**
** Parameter SZ is interpreted as an integer. If it is less than or
** equal to zero, then this function returns a copy of X. Or, if
** SZ is equal to the size of X when interpreted as a blob, also
** return a copy of X. Otherwise, decompress blob X using zlib
** utility function uncompress() and return the results (another
** blob).
*/
static void sqlarUncompressFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  uLong nData;
  uLongf sz;

  assert( argc==2 );
  sz = sqlite3_value_int(argv[1]);

  if( sz<=0 || sz==(nData = sqlite3_value_bytes(argv[0])) ){
    sqlite3_result_value(context, argv[0]);
  }else{
    const Bytef *pData= sqlite3_value_blob(argv[0]);
    Bytef *pOut = sqlite3_malloc(sz);
    if( Z_OK!=uncompress(pOut, &sz, pData, nData) ){
      sqlite3_result_error(context, "error in uncompress()", -1);
    }else{
      sqlite3_result_blob(context, pOut, sz, SQLITE_TRANSIENT);
    }
    sqlite3_free(pOut);
  }
}


#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_sqlar_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Unused parameter */
  rc = sqlite3_create_function(db, "sqlar_compress", 1, SQLITE_UTF8, 0,
                               sqlarCompressFunc, 0, 0);
  if( rc==SQLITE_OK ){
    rc = sqlite3_create_function(db, "sqlar_uncompress", 2, SQLITE_UTF8, 0,
                                 sqlarUncompressFunc, 0, 0);
  }
  return rc;
}

	./mkkeywordhash >keywordhash.h

# Source files that go into making shell.c
SHELL_SRC = \
	$(TOP)/src/shell.c.in \
	$(TOP)/ext/misc/shathree.c \
	$(TOP)/ext/misc/fileio.c \
	$(TOP)/ext/misc/completion.c


shell.c:	$(SHELL_SRC) $(TOP)/tool/mkshellc.tcl
	tclsh $(TOP)/tool/mkshellc.tcl >shell.c



# Rules to build the extension objects.

	./mkkeywordhash >keywordhash.h

# Source files that go into making shell.c
SHELL_SRC = \
	$(TOP)/src/shell.c.in \
	$(TOP)/ext/misc/shathree.c \
	$(TOP)/ext/misc/fileio.c \
	$(TOP)/ext/misc/completion.c \
	$(TOP)/ext/misc/sqlar.c

shell.c:	$(SHELL_SRC) $(TOP)/tool/mkshellc.tcl
	tclsh $(TOP)/tool/mkshellc.tcl >shell.c



# Rules to build the extension objects.

#define SQLITE_EXTENSION_INIT1
#define SQLITE_EXTENSION_INIT2(X) (void)(X)

INCLUDE ../ext/misc/shathree.c
INCLUDE ../ext/misc/fileio.c
INCLUDE ../ext/misc/completion.c
#ifdef SQLITE_HAVE_ZLIB
INCLUDE ../ext/misc/compress.c
#endif

#if defined(SQLITE_ENABLE_SESSION)
/*
** State information for a single open session
*/
typedef struct OpenSession OpenSession;
................................................................................
#ifndef SQLITE_OMIT_LOAD_EXTENSION
    sqlite3_enable_load_extension(p->db, 1);
#endif
    sqlite3_fileio_init(p->db, 0, 0);
    sqlite3_shathree_init(p->db, 0, 0);
    sqlite3_completion_init(p->db, 0, 0);
#ifdef SQLITE_HAVE_ZLIB
    sqlite3_compress_init(p->db, 0, 0);
#endif
    sqlite3_create_function(p->db, "shell_add_schema", 2, SQLITE_UTF8, 0,
                            shellAddSchemaName, 0, 0);
  }
}

#if HAVE_READLINE || HAVE_EDITLINE
................................................................................


/*
** Implementation of .ar "eXtract" command. 
*/
static int arExtractCommand(ShellState *p, sqlite3 *db, ArCommand *pAr){
  const char *zSql1 = 

    "SELECT :1 || name, writefile(:1 || name, "
    "CASE WHEN (data AND sz>=0 AND sz!=length(data)) THEN "
    "    uncompress(data) "
    "ELSE"
    "    data "
    "END, "
    "mode, mtime) FROM sqlar WHERE (%s) AND (data IS NULL OR :2 = 0)";

  struct timespec times[2];
  sqlite3_stmt *pSql = 0;
  int rc = SQLITE_OK;
  char *zDir = 0;
  char *zWhere = 0;
  int i;
................................................................................
      "name TEXT PRIMARY KEY,  -- name of the file\n"
      "mode INT,               -- access permissions\n"
      "mtime INT,              -- last modification time\n"
      "sz INT,                 -- original file size\n"
      "data BLOB               -- compressed content\n"
  ")";
  const char *zDrop = "DROP TABLE IF EXISTS sqlar";
  const char *zInsert = "REPLACE INTO sqlar VALUES(?, ?, ?, ?, ?)";

  sqlite3_stmt *pStmt = 0;        /* Directory traverser */
  sqlite3_stmt *pInsert = 0;      /* Compilation of zInsert */
  int i;                          /* For iterating through azFile[] */
  int rc;                         /* Return code */

  Bytef *aCompress = 0;           /* Compression buffer */
  int nCompress = 0;              /* Size of compression buffer */

  rc = sqlite3_exec(db, "SAVEPOINT ar;", 0, 0, 0);
  if( rc!=SQLITE_OK ) return rc;

  if( bUpdate==0 ){
    rc = sqlite3_exec(db, zDrop, 0, 0, 0);
    if( rc!=SQLITE_OK ) return rc;
  }
................................................................................
      sqlite3_bind_text(pInsert, 1, zName, -1, SQLITE_STATIC);
      sqlite3_bind_int(pInsert, 2, mode);
      sqlite3_bind_int64(pInsert, 3, (sqlite3_int64)mtime);

      if( S_ISDIR(mode) ){
        sz = 0;
        sqlite3_bind_null(pInsert, 5);


      }else if( S_ISLNK(mode) ){
        sz = -1;
        sqlite3_bind_value(pInsert, 5, sqlite3_column_value(pStmt, 3));
      }else{
        uLongf nReq;              /* Required size of compression buffer */
        const Bytef *pData = (const Bytef*)sqlite3_column_blob(pStmt, 3);
        sz = sqlite3_column_bytes(pStmt, 3);
        nReq = compressBound(sz);
        if( aCompress==0 || nReq>nCompress ){
          Bytef *aNew = sqlite3_realloc(aCompress, nReq);
          if( aNew==0 ){
            rc = SQLITE_NOMEM;
          }else{
            aCompress = aNew;
            nCompress = nReq;
          }
        }

        if( Z_OK!=compress(aCompress, &nReq, pData, sz) ){
          rc = SQLITE_ERROR;
        }
        if( nReq<sz ){
          sqlite3_bind_blob(pInsert, 5, aCompress, nReq, SQLITE_STATIC);
        }else{
          sqlite3_bind_blob(pInsert, 5, pData, sz, SQLITE_STATIC);
        }
      }

      if( rc==SQLITE_OK ){
        sqlite3_bind_int(pInsert, 4, sz);
        sqlite3_step(pInsert);
        rc = sqlite3_reset(pInsert);
      }
    }
    shellReset(&rc, pStmt);
  }

  if( rc!=SQLITE_OK ){
    sqlite3_exec(db, "ROLLBACK TO ar; RELEASE ar;", 0, 0, 0);
  }else{
    rc = sqlite3_exec(db, "RELEASE ar;", 0, 0, 0);
  }
  shellFinalize(&rc, pStmt);
  shellFinalize(&rc, pInsert);
  sqlite3_free(aCompress);
  return rc;
}

/*
** Implementation of .ar "Create" command. 
**
** Create the "sqlar" table in the database if it does not already exist.
................................................................................
        raw_printf(stderr, "cannot open file: %s (%s)\n", 
            cmd.zFile, sqlite3_errmsg(db)
        );
        sqlite3_close(db);
        return rc;
      }
      sqlite3_fileio_init(db, 0, 0);
      sqlite3_compress_init(db, 0, 0);
    }else{
      db = pState->db;
    }

    switch( cmd.eCmd ){
      case AR_CMD_CREATE:
        rc = arCreateCommand(pState, db, &cmd);

#define SQLITE_EXTENSION_INIT1
#define SQLITE_EXTENSION_INIT2(X) (void)(X)

INCLUDE ../ext/misc/shathree.c
INCLUDE ../ext/misc/fileio.c
INCLUDE ../ext/misc/completion.c
#ifdef SQLITE_HAVE_ZLIB
INCLUDE ../ext/misc/sqlar.c
#endif

#if defined(SQLITE_ENABLE_SESSION)
/*
** State information for a single open session
*/
typedef struct OpenSession OpenSession;
................................................................................
#ifndef SQLITE_OMIT_LOAD_EXTENSION
    sqlite3_enable_load_extension(p->db, 1);
#endif
    sqlite3_fileio_init(p->db, 0, 0);
    sqlite3_shathree_init(p->db, 0, 0);
    sqlite3_completion_init(p->db, 0, 0);
#ifdef SQLITE_HAVE_ZLIB
    sqlite3_sqlar_init(p->db, 0, 0);
#endif
    sqlite3_create_function(p->db, "shell_add_schema", 2, SQLITE_UTF8, 0,
                            shellAddSchemaName, 0, 0);
  }
}

#if HAVE_READLINE || HAVE_EDITLINE
................................................................................


/*
** Implementation of .ar "eXtract" command. 
*/
static int arExtractCommand(ShellState *p, sqlite3 *db, ArCommand *pAr){
  const char *zSql1 = 
    "SELECT "
    "  :1 || name, "

    "  writefile(:1 || name, sqlar_uncompress(data, sz), mode, mtime) "



    "FROM sqlar WHERE (%s) AND (data IS NULL OR :2 = 0)";

  struct timespec times[2];
  sqlite3_stmt *pSql = 0;
  int rc = SQLITE_OK;
  char *zDir = 0;
  char *zWhere = 0;
  int i;
................................................................................
      "name TEXT PRIMARY KEY,  -- name of the file\n"
      "mode INT,               -- access permissions\n"
      "mtime INT,              -- last modification time\n"
      "sz INT,                 -- original file size\n"
      "data BLOB               -- compressed content\n"
  ")";
  const char *zDrop = "DROP TABLE IF EXISTS sqlar";
  const char *zInsert = "REPLACE INTO sqlar VALUES(?,?,?,?,sqlar_compress(?))";

  sqlite3_stmt *pStmt = 0;        /* Directory traverser */
  sqlite3_stmt *pInsert = 0;      /* Compilation of zInsert */
  int i;                          /* For iterating through azFile[] */
  int rc;                         /* Return code */




  rc = sqlite3_exec(db, "SAVEPOINT ar;", 0, 0, 0);
  if( rc!=SQLITE_OK ) return rc;

  if( bUpdate==0 ){
    rc = sqlite3_exec(db, zDrop, 0, 0, 0);
    if( rc!=SQLITE_OK ) return rc;
  }
................................................................................
      sqlite3_bind_text(pInsert, 1, zName, -1, SQLITE_STATIC);
      sqlite3_bind_int(pInsert, 2, mode);
      sqlite3_bind_int64(pInsert, 3, (sqlite3_int64)mtime);

      if( S_ISDIR(mode) ){
        sz = 0;
        sqlite3_bind_null(pInsert, 5);
      }else{
        sqlite3_bind_value(pInsert, 5, sqlite3_column_value(pStmt, 3));
        if( S_ISLNK(mode) ){
          sz = -1;

        }else{


          sz = sqlite3_column_bytes(pStmt, 3);


















        }
      }


      sqlite3_bind_int(pInsert, 4, sz);
      sqlite3_step(pInsert);
      rc = sqlite3_reset(pInsert);

    }
    shellReset(&rc, pStmt);
  }

  if( rc!=SQLITE_OK ){
    sqlite3_exec(db, "ROLLBACK TO ar; RELEASE ar;", 0, 0, 0);
  }else{
    rc = sqlite3_exec(db, "RELEASE ar;", 0, 0, 0);
  }
  shellFinalize(&rc, pStmt);
  shellFinalize(&rc, pInsert);

  return rc;
}

/*
** Implementation of .ar "Create" command. 
**
** Create the "sqlar" table in the database if it does not already exist.
................................................................................
        raw_printf(stderr, "cannot open file: %s (%s)\n", 
            cmd.zFile, sqlite3_errmsg(db)
        );
        sqlite3_close(db);
        return rc;
      }
      sqlite3_fileio_init(db, 0, 0);
      sqlite3_sqlar_init(db, 0, 0);
    }else{
      db = pState->db;
    }

    switch( cmd.eCmd ){
      case AR_CMD_CREATE:
        rc = arCreateCommand(pState, db, &cmd);