SQLite

  set scan(littleEndian) i*
  set scan(bigEndian) I*
  binary scan $blob $scan($::tcl_platform(byteOrder)) r
  return $r
}
db func mit mit

proc fix_phrase_expr {cols expr colfiltervar} {
  upvar $colfiltervar iColFilter

  set out [list]
  foreach t $expr {
    if {[string match *:* $t]} {
      set col [lindex [split $t :] 0]
      set t   [lindex [split $t :] 1]
      set iCol [lsearch $cols $col]
      if {$iCol<0} { error "unknown column: $col" }
      if {$iColFilter < 0} {
        set iColFilter $iCol
      } elseif {$iColFilter != $iCol} {
        set iColFilter [llength $cols]
      }
    }
    lappend out $t
  }

  return $out
}

proc fix_near_expr {cols expr colfiltervar} { 
  upvar $colfiltervar iColFilter
 
  set iColFilter -1

  set out [list]
  lappend out [fix_phrase_expr $cols [lindex $expr 0] iColFilter]
  foreach {a b} [lrange $expr 1 end] {
    if {[string match -nocase near $a]}   { set a 10 }
    if {[string match -nocase near/* $a]} { set a [string range $a 5 end] }
    lappend out $a
    lappend out [fix_phrase_expr $cols $b iColFilter]
  }
  return $out
}

proc get_single_near_results {tbl expr deferred arrayvar nullvar} {
  upvar $arrayvar aMatchinfo
  upvar $nullvar nullentry
  catch {array unset aMatchinfo}

  set cols [list]
  set miss [list]
  db eval "PRAGMA table_info($tbl)" A { lappend cols $A(name) ; lappend miss 0 }
  set expr [fix_near_expr $cols $expr iColFilter]

  # Calculate the expected results using [fts3_near_match]. The following
  # loop populates the "hits" and "counts" arrays as follows:
  # 
  #   1. For each document in the table that matches the NEAR expression,
  #      hits($docid) is set to 1. The set of docids that match the expression
  #      can therefore be found using [array names hits].
  #
  #   2. For each column of each document in the table, counts($docid,$iCol)
  #      is set to the -phrasecountvar output.
  #
  set res [list]
  catch { array unset hits }
  db eval "SELECT docid, * FROM $tbl" d {
    set iCol 0
    foreach col [lrange $d(*) 1 end] {
      set docid $d(docid)
      if {$iColFilter<0 || $iCol==$iColFilter} {
        set hit [fts3_near_match $d($col) $expr -p counts($docid,$iCol)]
        if {$hit} { set hits($docid) 1 }
      } else {
        set counts($docid,$iCol) $miss
      }
      incr iCol
    }
  }
  set nPhrase [expr ([llength $expr]+1)/2]
  set nCol $iCol

  # This block populates the nHit and nDoc arrays. For each phrase/column

}

#--------------------------------------------------------------------------
# The following test cases - fts3auto-5.* - focus on using prefix indexes.
#
set chunkconfig [fts3_configure_incr_load 1 1]
foreach {tn create pending} {


  1    "fts4(a, b)"                                  1
  2    "fts4(a, b, order=ASC, prefix=1)"             1
  3    "fts4(a, b, order=ASC,  prefix=1,3)"          0
  4    "fts4(a, b, order=DESC, prefix=2,4)"          0
  5    "fts4(a, b, order=DESC, prefix=1)"            0
  6    "fts4(a, b, order=ASC,  prefix=1,3)"          0
} {

  execsql [subst {

  do_fts3query_test 5.$tn.1.5 t1 {a*}
  do_fts3query_test 5.$tn.1.6 t1 {th* NEAR/5 a* NEAR/5 w*}
  do_fts3query_test 5.$tn.1.7 t1 {"b* th* art* fair*"}

  if {$pending} {execsql COMMIT}
}
eval fts3_configure_incr_load $chunkconfig

foreach {tn pending create} {
  1    0 "fts4(a, b, c, d)"
  2    1 "fts4(a, b, c, d)"
  3    0 "fts4(a, b, c, d, order=DESC)"
  4    1 "fts4(a, b, c, d, order=DESC)"
} {
  execsql [subst {
    DROP TABLE IF EXISTS t1;
    CREATE VIRTUAL TABLE t1 USING $create;
  }]


  if {$pending} { execsql BEGIN }

  foreach {a b c d} {
    "A B C" "D E F" "G H I" "J K L"
    "B C D" "E F G" "H I J" "K L A"
    "C D E" "F G H" "I J K" "L A B"
    "D E F" "G H I" "J K L" "A B C"
    "E F G" "H I J" "K L A" "B C D"
    "F G H" "I J K" "L A B" "C D E"
  } {
    execsql { INSERT INTO t1 VALUES($a, $b, $c, $d) }
  }

  do_fts3query_test 6.$tn.1 t1 {b:G}
  do_fts3query_test 6.$tn.2 t1 {b:G AND c:I}
  do_fts3query_test 6.$tn.3 t1 {b:G NEAR c:I}
  do_fts3query_test 6.$tn.4 t1 {a:C OR b:G OR c:K OR d:C}
  do_fts3query_test 6.$tn.5 t1 {a:G OR b:G}

  catchsql { COMMIT }
}

set sqlite_fts3_enable_parentheses $sfep
finish_test