# 2020-01-29
#
# 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.
#
#***********************************************************************
# 

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix bestindex8

ifcapable !vtab {
  finish_test
  return
}

register_tcl_module db

proc vtab_command {src method args} {
  switch -- $method {
    xConnect {
      return "CREATE TABLE xxx(a, b)"
    }

    xBestIndex {
      set hdl [lindex $args 0]
      set clist [$hdl constraints]
      set orderby [$hdl orderby]
      lappend ::lBestIndexDistinct [$hdl distinct]

      #puts "ORDERBY: $orderby" 
      set iCons 0
      set ret [list]
      foreach cons $clist {
        catch { array unset C }
        array set C $cons
        if {$C(usable)} {
          lappend ret use $iCons
        }
        incr iCons
      }
      if {$orderby=="{column 0 desc 0} {column 1 desc 0}"
       || $orderby=="{column 0 desc 0}"
      } {
        lappend ret orderby 1
        lappend ret idxnum 1
        set ::lOrderByConsumed 1
      }
      return $ret
    }

    xFilter {
      set idxnum [lindex $args 0]
      if {$idxnum} {
        return [list sql "SELECT rowid, a, b FROM $src order by 2, 3"]
      }
      return [list sql "SELECT rowid, a, b FROM $src"]
    }

  }

  return {}
}

do_execsql_test 1.0 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a, b);
  INSERT INTO t1 VALUES('a', 'b'), ('c', 'd');
  INSERT INTO t1 VALUES('a', 'b'), ('c', 'd');
  CREATE VIRTUAL TABLE vt1 USING tcl(vtab_command t1);

  CREATE TABLE t0(c0);
  INSERT INTO t0(c0) VALUES (1), (0);
}

foreach {tn sql bDistinct idxinsert bConsumed res} {
  1 "SELECT a, b FROM vt1"                              0 0 0 {a b c d a b c d}
  2 "SELECT DISTINCT a, b FROM vt1"                     2 1 1 {a b c d}
  3 "SELECT DISTINCT a FROM vt1"                        2 1 1 {a c}
  4 "SELECT DISTINCT b FROM vt1"                        2 1 0 {b d}
  5 "SELECT DISTINCT b FROM vt1 ORDER BY a"             0 1 1 {b d}
  6 "SELECT DISTINCT t0.c0 FROM vt1, t0 ORDER BY vt1.a" 0 1 1 {1 0}
  7 "SELECT DISTINCT a, b FROM vt1 ORDER BY a, b"       3 0 1 {a b c d}
  8 "SELECT DISTINCT a, b FROM vt1 ORDER BY a"          0 1 1 {a b c d}
  9 "SELECT DISTINCT a FROM vt1 ORDER BY a, b"          0 1 1 {a c}

 10 "SELECT DISTINCT a, b FROM vt1 WHERE b='b'"         2 1 1 {a b}
 11 "SELECT DISTINCT a, b FROM vt1 WHERE +b='b'"        2 1 1 {a b}
} {
  set ::lBestIndexDistinct ""
  set ::lOrderByConsumed 0
  do_execsql_test 1.$tn.1 $sql $res
  do_test 1.$tn.2 {
    set ::lBestIndexDistinct
  } $bDistinct
  do_test 1.$tn.3 {
    expr {[lsearch [execsql "explain $sql"] IdxInsert]>=0}
  } $idxinsert
  do_test 1.$tn.4 {
    set ::lOrderByConsumed
  } $bConsumed
}

#-------------------------------------------------------------------------
reset_db
register_tcl_module db

proc vtab_command {src method args} {
  switch -- $method {
    xConnect {
      return "CREATE TABLE xxx(a, b)"
    }

    xBestIndex {
      set hdl [lindex $args 0]
      set ret [list]

      set iCons 0
      foreach cons [$hdl constraints] {
        array set C $cons
        if {($C(op)=="limit" || $C(op)=="offset") && $C(usable)} {
          lappend ret use $iCons
        }
        incr iCons
      }

      return $ret
    }

    xFilter {
      lappend ::lFilterArgs [lindex $args 2]
      return [list sql "SELECT rowid, a, b FROM $src"]
    }

  }

  return {}
}

do_execsql_test 2.0 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a, b);
  CREATE VIRTUAL TABLE vt1 USING tcl(vtab_command t1);
}

do_test 2.1 {
  set ::lFilterArgs [list]
  execsql { SELECT * FROM vt1 LIMIT 10 }
  set ::lFilterArgs
} {10}

do_test 2.2 {
  set ::lFilterArgs [list]
  execsql { SELECT * FROM vt1 LIMIT 5 OFFSET 50 }
  set ::lFilterArgs
} {{50 5}}

do_test 2.3 {
  set ::lFilterArgs [list]
  execsql { SELECT * FROM vt1 ORDER BY a, b LIMIT 1 OFFSET 1 }
  set ::lFilterArgs
} {{1 1}}

do_test 2.4 {
  set ::lFilterArgs [list]
  execsql { SELECT * FROM vt1 ORDER BY a, +b LIMIT 1 OFFSET 1 }
  set ::lFilterArgs
} {{}}

#-------------------------------------------------------------------------
reset_db
register_tcl_module db

proc vtab_command {src method args} {
  switch -- $method {
    xConnect {
      return "CREATE TABLE xxx(a, b)"
    }

    xBestIndex {
      set hdl [lindex $args 0]
      set lCons [$hdl constraints]

      set ret [list]
      for {set i 0} {$i < [llength $lCons]} {incr i} {
        array set C [lindex $lCons $i]
        if {$C(usable)} {
          lappend ret use $i
          $hdl in $i 1
        }
      }
      return $ret
    }

    xFilter {
      set lArg [lindex $args 2]
      lappend ::lFilterArg {*}$lArg
      return [list sql "SELECT rowid, a, b FROM $src"]
    }

  }

  return {}
}

do_execsql_test 3.0 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a, b);
  CREATE VIRTUAL TABLE vt1 USING tcl(vtab_command t1);
}

foreach {tn sql lfa} {
  1 "SELECT * FROM vt1 WHERE b IN (10, 20, 30)" {{10 20 30}}
  2 "SELECT * FROM vt1 WHERE b IN ('abc', 'def')" {{abc def}}
  3 "SELECT * FROM vt1 WHERE a IS NULL AND b IN ('abc', 'def')" {{} {abc def}}
  4 "SELECT * FROM vt1 WHERE a IN (1,2,3) AND b IN ('abc', 'def')" 
     {{1 2 3} {abc def}}

  5 "SELECT * FROM vt1 
     WHERE a IN (SELECT 1 UNION SELECT 2) AND b IN ('abc', 'def')"
     {{1 2} {abc def}}

  6 "SELECT * FROM vt1 
     WHERE b IN ('abc', 'def') AND a IN (SELECT 1 UNION SELECT 2)"
     {{abc def} {1 2}}
} {
  do_test 3.$tn {
    set ::lFilterArg [list]
    execsql $sql
    set ::lFilterArg
  } $lfa
}

#explain_i { SELECT * FROM vt1 WHERE b IN (10, 20, 30) }

#-------------------------------------------------------------------------
reset_db
register_tcl_module db

proc vtab_command {src method args} {
  switch -- $method {
    xConnect {
      return "CREATE TABLE xxx(a, b, c)"
    }

    xBestIndex {
      set hdl [lindex $args 0]
      set lCons [$hdl constraints]

      set ret [list]
      for {set i 0} {$i < [llength $lCons]} {incr i} {
        lappend ::lBestIndexRhs [$hdl rhs_value $i -]
      }
      return $ret
    }

    xFilter {
      return [list sql "SELECT rowid, a, b, c FROM $src"]
    }

  }

  return {}
}

do_execsql_test 4.0 {
  CREATE TABLE t1(a, b, c);
  CREATE VIRTUAL TABLE vt1 USING tcl(vtab_command t1);
}

foreach {tn sql lbir} {
  1 "SELECT * FROM vt1 WHERE b = 10" {10}
  2 "SELECT * FROM vt1 WHERE a = 'abc' AND b < 30" {abc 30}
  3 "SELECT * FROM vt1 WHERE a = 'abc' AND b < 30+2" {abc -}
  4 "SELECT * FROM vt1 WHERE a IN (1,2,3) AND b < 30+2" {- -}
  5 "SELECT * FROM vt1 WHERE a IS 111 AND b < 30+2" {111 -}
} {
  do_test 4.$tn {
    set ::lBestIndexRhs [list]
    execsql $sql
    set ::lBestIndexRhs
  } $lbir
}

#-------------------------------------------------------------------------
reset_db
db cache size 0
register_tcl_module db

set ::vtab_handle_in 1
proc vtab_command {src method args} {
  switch -- $method {
    xConnect {
      return "CREATE TABLE xxx(a, b, c)"
    }

    xBestIndex {
      set lCols [list a b c]

      set hdl [lindex $args 0]
      set lCons [$hdl constraints]
      set lOrder [$hdl order]

      set L ""
      set O ""
      set W [list]
      set a 0
      for {set i 0} {$i < [llength $lCons]} {incr i} {
        array set C [lindex $lCons $i]
        if {$C(usable)} {
          if { $C(op)=="eq" } {
            set bIn 0
            if {$::vtab_handle_in} { set bIn [$hdl in $i 1] }
            if {$bIn} {
              lappend W "[lindex $lCols $C(column)] IN (%I$a%)"
            } else {
              lappend W "[lindex $lCols $C(column)] = %$a%"
            }
            lappend ret omit $i
          }
          if { $C(op)=="limit"  } { set L " LIMIT %$a%"  ; lappend ret use $i }
          if { $C(op)=="offset" } { set O " OFFSET %$a%" ; lappend ret use $i }
          incr a
        }
      }

      set order ""
      set selectlist "rowid, a, b, c"
      if {[llength $lOrder]} {
        array set sl [list]
        set lO [list]
        foreach s $lOrder {
          array set C $s
          set ad ""
          if {$C(desc)} { set ad " DESC" }
          lappend lO "[lindex $lCols $C(column)]$ad"
          set sl($C(column)) 1
        }
        if {[$hdl distinct]==2} {
          set selectlist "DISTINCT 0"
          foreach i {0 1 2} {
            if {[info exists sl($i)]} {
              append selectlist ", [lindex $lCols $i]"
            } else {
              append selectlist ", 0"
            }
          }
        } else {
          set order " ORDER BY [join $lO ,]"
        }
      }

      set where ""
      if {[llength $W]} { set where " WHERE [join $W { AND }]" }
      set sql "SELECT $selectlist FROM $src$where$order$L$O"

      lappend ret idxStr $sql
      return $ret
    }

    xFilter {
      foreach {idxnum idxstr lArg} $args {}
      set ii 0
      set sql $idxstr
      foreach a $lArg {
        set sql [string map [list %$ii% $a] $sql]
        set sql [string map [list %I$ii% [join $a ,]] $sql]
        incr ii
      }
      lappend ::lFilterSql $sql

      if {[regexp {OFFSET (.*)$} $sql -> off]} {
        set real_sql "
          WITH c(i) AS ( SELECT 1 UNION ALL SELECT i+1 FROM c WHERE i<$off )
          SELECT 0,0,0,0 FROM c
          UNION ALL SELECT * FROM (
            $sql
          )
        "
      } else {
        set real_sql $sql
      }

      return [list sql $real_sql]
    }

  }

  return {}
}

do_execsql_test 5.0 {
  CREATE TABLE t1(a, b, c);
  CREATE VIRTUAL TABLE vt1 USING tcl(vtab_command t1);
  INSERT INTO t1 VALUES(1, 2, 3);
  INSERT INTO t1 VALUES(2, 3, 4);
  INSERT INTO t1 VALUES(3, 4, 5);
  INSERT INTO t1 VALUES(1, 5, 6);
  INSERT INTO t1 VALUES(2, 6, 7);
  INSERT INTO t1 VALUES(3, 7, 8);
  INSERT INTO t1 VALUES(1, 8, 9);
  INSERT INTO t1 VALUES(2, 9, 0);
}

proc do_vtab_test {tn sql vtsql {res {}}} {
  set ::lFilterSql [list]
  uplevel [list do_execsql_test $tn.1 $sql $res]
  uplevel [list do_test $tn.2 {set ::lFilterSql} [list {*}$vtsql]]
}

do_vtab_test 5.1.1 {
  SELECT DISTINCT a FROM vt1
} {
  {SELECT DISTINCT 0, a, 0, 0 FROM t1}
} {1 2 3}

do_vtab_test 5.1.2 {
  SELECT DISTINCT a FROM vt1 ORDER BY a
} {
  {SELECT rowid, a, b, c FROM t1 ORDER BY a}
} {1 2 3}

do_vtab_test 5.1.3 {
  SELECT DISTINCT a FROM vt1 WHERE c IN (4,5,6,7,8)
} {
  {SELECT DISTINCT 0, a, 0, 0 FROM t1 WHERE c IN (4,5,6,7,8)}
} {2 3 1}

set ::vtab_handle_in 0
do_vtab_test 5.1.4 {
  SELECT  DISTINCT a FROM vt1 WHERE c IN (4,5,6,7,8)
} {
  {SELECT DISTINCT 0, a, 0, 0 FROM t1 WHERE c = 4}
  {SELECT DISTINCT 0, a, 0, 0 FROM t1 WHERE c = 5}
  {SELECT DISTINCT 0, a, 0, 0 FROM t1 WHERE c = 6}
  {SELECT DISTINCT 0, a, 0, 0 FROM t1 WHERE c = 7}
  {SELECT DISTINCT 0, a, 0, 0 FROM t1 WHERE c = 8}
} {2 3 1}

set ::vtab_handle_in 1
do_vtab_test 5.1.5a {
  SELECT a, b, c FROM vt1 WHERE c IN (4,5,6,7,8) LIMIT 2 OFFSET 2
} {
  {SELECT rowid, a, b, c FROM t1 WHERE c IN (4,5,6,7,8) LIMIT 2 OFFSET 2}
} {1 5 6 2 6 7}

set ::vtab_handle_in 0
do_vtab_test 5.1.5b {
  SELECT a, b, c FROM vt1 WHERE c IN (4,5,6,7,8) LIMIT 2 OFFSET 2
} {
  {SELECT rowid, a, b, c FROM t1 WHERE c = 4}
  {SELECT rowid, a, b, c FROM t1 WHERE c = 5}
  {SELECT rowid, a, b, c FROM t1 WHERE c = 6}
  {SELECT rowid, a, b, c FROM t1 WHERE c = 7}
} {1 5 6 2 6 7}
set ::vtab_handle_in 1

finish_test