-- Copyright (c) 1991-2002, The Numerical ALgorithms Group Ltd.
-- All rights reserved.
-- Copyright (C) 2007-2012, Gabriel Dos Reis.
-- All rights reserved.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions are
-- met:
--
--     - Redistributions of source code must retain the above copyright
--       notice, this list of conditions and the following disclaimer.
--
--     - Redistributions in binary form must reproduce the above copyright
--       notice, this list of conditions and the following disclaimer in
--       the documentation and/or other materials provided with the
--       distribution.
--
--     - Neither the name of The Numerical ALgorithms Group Ltd. nor the
--       names of its contributors may be used to endorse or promote products
--       derived from this software without specific prior written permission.
--
-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
-- IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
-- TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
-- PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
-- OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-- EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
-- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
-- PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
-- LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
-- NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import g_-util
namespace BOOT

--=======================================================================
--                        Build Directories
--=======================================================================
buildFunctionTable(dicts) ==
  sayKeyedMsg("S2GL0011",nil)
  buildWordTable getListOfFunctionNames dicts
 
buildWordTable u ==
  table:= hashTable 'EQ
  for s in u repeat
    key := charUpcase stringChar(s,0)
    tableValue(table,key) := [[s,:wordsOfString s],:tableValue(table,key)]
  for [key,:val] in entries table repeat
    tableValue(table,key) := 
      listSort(function GLESSEQP,removeDupOrderedAlist
        listSort(function GLESSEQP,val,function first),function second)
  table
 
writeFunctionTables(filemode) ==
  $functionTable := nil
  writeFunctionTable(filemode,'SPADU,'(SPAD))
  $functionTable := nil
  writeFunctionTable(filemode,'SPADD,'(SPADSYS))
  $functionTable := nil
  writeFunctionTable(filemode,'SPADC,'(SPADSYS SCRATCHPAD_-COMPILER))
  $functionTable := nil
  'done
 
writeFunctionTable(filemode,name,dicts) ==
  removeFile makeFullFilePath makePathname(name,'DATABASE,filemode)
  stream:= writeLib(name,'DATABASE)
  if not $functionTable then
    $functionTable:= buildFunctionTable dicts
  for [key,:val] in entries $functionTable repeat
    rwrite(object2Identifier key,val,stream)
  RSHUT stream
  'done
 
readFunctionTable() ==
  sayKeyedMsg("S2GL0011",nil)
  name :=
    $wordDictionary = 'user => 'SPADU
    $wordDictionary = 'development => 'SPADD
    'SPADC
  stream:= readLib(name,'DATABASE)
  table:= hashTable 'EQ
  for key in RKEYIDS makePathname(name,'DATABASE,"*") repeat
    tableValue(table,kk:=object2Identifier key) := rread(kk,stream,nil)
  RSHUT stream
  table
 
removeDupOrderedAlist u ==
  -- removes duplicate entries in ordered alist
  -- (where duplicates are adjacent)
  for x in tails u repeat
    (y := rest x) and first first x = first first y => x.rest := rest y
  u
 
getListOfFunctionNames(fnames) ==
  -- fnames is a list of directories
  res := nil
  for fn in fnames repeat
    null IOSTATE(fn,'DIRECT,'_*) => 'iterate
    stream:= DEFIOSTREAM(['(MODE . INPUT),['FILE,fn,'DIRECT,'_*]],80,0)
    while (x:= readLine stream) ~= %nothing repeat
      (s := # x) < 26 => 'iterate
      res:= [subString(x,26),:res]
    SHUT stream
  res
 
wordsOfString(s) ==
  [stringUpcase x for x in wordsOfStringKeepCase s]
 
wordsOfStringKeepCase s == wordsOfString1(s,0) or [copyTree s]
 
wordsOfString1(s,j) ==
  k := or/[i for i in j..(maxIndex(s)-1) | isBreakCharacter stringChar(s,i)] =>
    tailWords:=
      isBreakCharacter s.(k+1) =>
        n:= or/[i for i in (k+2)..(maxIndex(s)-1)|not isBreakCharacter stringChar(s,i)]
        null n => [subString(s,k)]
        n > k+1 => [subString(s,k,n-k-1),:wordsOfString1(s,n-1)]
      m := or/[i for i in (k+2)..(maxIndex(s)-1) | isBreakCharacter stringChar(s,i)] =>
        [subString(s,k,m-k),:wordsOfString1(s,m)]
      [subString(s,k)]
    k > j+1 => [subString(s,j,k-j),:tailWords]
    tailWords
  nil
 
isBreakCharacter x == null SMALL__LITER x
 
--=======================================================================
--               Augment Function Directories
--=======================================================================
add2WordFunctionTable fn ==
--called from DEF
  $functionTable and
    null LASSOC(s := PNAME fn,tableValue($functionTable,(key := UPCASE s.0))) =>
      tableValue($functionTable,key) := [[s,:wordsOfString s],:tableValue($functionTable,key)]
 
--=======================================================================
--                       Guess Function Name
--=======================================================================
guess word ==
  u := bootFind word => makeSymbol u
  nil
 
bootFind word ==
  not $useWordFacility => nil
  list:= bootSearch word
  PNAME word in list => nil --mismatch of directories: pretend it was not found
  null list => centerAndHighlight('"no match found",80,'" ")
  1 = #list => doYouWant? first list
  pickANumber(word,list)
 
doYouWant? nam ==
  center80 ['"Do you mean",:bright nam,'"?"]
  center80 ['"If so, type",:bright 'y,"or",:bright 'yes]
  center80 ['"Anything else means",:bright 'no]
  x := UPCASE queryUser nil
  STRING2ID_-N(x,1) in '(Y YES) => nam
  nil
 
pickANumber(word,list) ==
  clearScreen()
  centerNoHighlight(['"You asked for",:bright word],80,'"-")
  centerAndHighlight('"Do you mean one of the following?",80,'" ")
  n:= #list
  xx:= (n > 99 => 3; n > 9 => 2; 1)
  maxWidth:= 38 - 2*(1+xx)
  [short,long] := say2Split(list,nil,nil,maxWidth)
  extra:=
    REMAINDER(length := # short,2) ~= 0 => 1
    0
  halfLength:= length/2
  firstList:= take(halfLength,short)
  secondList:= take(-halfLength,short)
  secondStartIndex:= halfLength + extra
  shortList:=
    "append"/[[[:bright i,fillerSpaces(xx-WIDTH i,char " "),x],
      [:bright(i+secondStartIndex),fillerSpaces(xx-WIDTH (i+halfLength),char " "),y]]
        for i in 1.. for x in firstList for y in secondList]
  say2PerLineThatFit shortList
  i:= 1 + halfLength
  if extra=1 then
    sayBrightly [:bright i,fillerSpaces(xx-WIDTH i,char " "),list.(i-1)]
  for x in long for i in (1+length).. repeat
    sayBrightly [:bright i,fillerSpaces(xx-WIDTH i,char " "),x]
  center80 ['"If so: type a number between",:bright 1,'"and",:bright n,"and ENTER"]
  center80 ['"Anything else means",:bright 'no]
  y := queryUser nil
  x:= string2Integer y
  integer? x and x >= 1 and x <= #list => list.(x-1)
  nil
 
bootSearch word ==
--if not $functionTable then $functionTable:= buildFunctionTable()
  if not $functionTable then $functionTable:= readFunctionTable()
  key := PNAME word
  list :=
    hasWildCard? key =>
      pattern := patternTran key -- converts * to &
      pattern.0 ~= char "&" =>
        [x for [x,:.] in tableValue($functionTable,UPCASE pattern.0)|
          match?(pattern,copyTree x)]
      "append"/[[x for [x,:.] in v | match?(pattern,copyTree x)]
                  for [k,:v] in entries $functionTable]
    findApproximateWords(PNAME word,$functionTable)
  list
 
findApproximateWords(word,table) ==
  words:= wordsOfString word
  upperWord:= UPCASE copyTree word
  n := #words
  threshold:=
    n = 1 => 3
    4
  alist:= tableValue(table,UPCASE word.0)
 
  --first try to break up as list of words
  firstTry := [x for [x,:wordList] in alist | p] where p() ==
    n = #wordList =>
      sum := 0
      for entry in wordList for part in words while sum < threshold repeat
        sum:= sum + deltaWordEntry(part,entry)
      sum < threshold => true
      n < 3 => false
      sum := 0
      badWord := false
      for entry in wordList for part in words while sum < threshold repeat
        k:= deltaWordEntry(part,entry)
        k < 2 => sum:= sum + k
        null badWord => badWord := true
        sum := 1000
      sum < threshold
    n+1 = #wordList =>    --assume one word is missing
      sum := 0
      badWord := false
      for entries in tails wordList for part in words
           while sum < threshold repeat
        entry := first entries
        k:= deltaWordEntry(part,entry)
        k < 2 => sum:= sum + k
        null badWord =>
          badWord := true
          entries := rest entries      --skip this bad word
          entry := first entries
          k := deltaWordEntry(part,entry)
          k < 2 => sum := sum + k
          sum := 1000
        sum := 1000
      sum < threshold
    n-1 = #wordList =>    --assume one word too many
      sum := 0
      badWord := false
      for entry in wordList for parts in tails words
           while sum < threshold repeat
        part := first parts
        k:= deltaWordEntry(part,entry)
        k < 2 => sum:= sum + k
        null badWord =>
          badWord := true
          parts := rest parts      --skip this bad word
          part := first parts
          k := deltaWordEntry(part,entry)
          k < 2 => sum := sum + k
          sum := 1000
        sum := 1000
      sum < threshold
    false
  firstTry => firstTry
 
  --no winners, so try flattening to upper case and checking again
 
  wordSize := # word
  lastThreshold := MAX(3,wordSize/2)
  vec := GETREFV lastThreshold
  for [x,:.] in alist repeat
    k := deltaWordEntry(upperWord,UPCASE copyTree x)
    k < lastThreshold => vec.k := [x,:vec.k]
  or/[vec.k for k in 0..maxIndex vec]
 
guessFromList(key,stringList) ==
  threshold := MAX(3,(# key)/2)
  vec := GETREFV threshold
  for x in stringList repeat
    k := deltaWordEntry(key,x)
    k < threshold => vec.k := [x,:vec.k]
  or/[vec.k for k in 0..maxIndex vec]
 
deltaWordEntry(word,entry) ==
  word = entry => 0
  abs(diff := # word - # entry) > 4 => 1000
  canForgeWord(word,entry)
 
--+ Note these are optimized definitions below-- see commented out versions
--+   to understand the algorithm
canForgeWord(word,entry) ==
  forge(word,0,maxIndex word,entry,0,maxIndex entry,0)
 
forge(word,w,W,entry,e,E,n) ==
  w > W =>
    e > E => n
    E-e + n + 1
  e > E => W-w + n + 1
  word.w = entry.e => forge(word,w+1,W,entry,e+1,E,n)
  w=W or e=E => forge(word,w+1,W,entry,e+1,E,n + 1)
  word.w=entry.(e+1) =>
    word.(w+1) = entry.e => forge(word,w+2,W,entry,e+2,E,n + 1)
    forge(word,w+1,W,entry,e+2,E,n + 1)
  word.(w+1)=entry.e => forge(word,w+2,W,entry,e+1,E,n + 1)
 
  (deltaW := W-w) > 1 and (deltaE := E-e) > 1 =>
    --if word is long, can we delete chars to match 2 consective chars
    deltaW >= deltaE and
      (k := or/[j for j in (w+2)..(W-1) | word.j = entry.e])
        and word.(k+1) = entry.(e+1) =>
          forge(word,k+2,W,entry,e+2,E,k-w + n)
    deltaW <= deltaE and
    --if word is short, can we insert chars so as to match 2 consecutive chars
      (k := or/[j for j in (e+2)..(E-1) | word.w = entry.j])
        and word.(w+1) = entry.(k+1) =>
          forge(word,w+2,W,entry,k+2,E,n + k-e)
    forge(word,w+1,W,entry,e+1,E,n + 1)
  --check for two consecutive matches down the line
  forge(word,w+1,W,entry,e+1,E,n + 1)
 
--+ DO NOT REMOVE DEFINITIONS BELOW which explain the algorithm
--+ canForgeWord(word,entry) ==--
--+ [d,i,s,t] := forge(word,0,maxIndex word,entry,0,maxIndex entry,0,0,0,0)
--+ --d=deletions, i=insertions, s=substitutions, t=transpositions
--+ --list is formed only for tuning purposes-- remove later on
--+ d + i + s + t
 
--+forge(word,w,W,entry,e,E,d,i,s,t) ==
--+  w > W =>
--+    e > E => [d,i,s,t]
--+    [d,E-e+i+1,s,t]
--+  e > E => [W-w+d+1,i,s,t]
--+  word.w = entry.e => forge(word,w+1,W,entry,e+1,E,d,i,s,t)
--+  w=W or e=E => forge(word,w+1,W,entry,e+1,E,d,i,s+1,t)
--+  word.w=entry.(e+1) =>
--+    word.(w+1) = entry.e => forge(word,w+2,W,entry,e+2,E,d,i,s,t+1)
--+    forge(word,w+1,W,entry,e+2,E,d,i+1,s,t)
--+  word.(w+1)=entry.e => forge(word,w+2,W,entry,e+1,E,d+1,i,s,t)
--+
--+  (deltaW := W-w) > 1 and (deltaE := E-e) > 1 =>
--+    --if word is long, can we delete chars to match 2 consective chars
--+    deltaW >= deltaE and
--+      (k := or/[j for j in (w+2)..(W-1) | word.j = entry.e])
--+        and word.(k+1) = entry.(e+1) =>
--+          forge(word,k+2,W,entry,e+2,E,d+k-w,i,s,t)
--+    deltaW <= deltaE and
--+    --if word is short, can we insert chars so as to match 2 consecutive chars
--+      (k := or/[j for j in (e+2)..(E-1) | word.w = entry.j])
--+        and word.(w+1) = entry.(k+1) =>
--+          forge(word,w+2,W,entry,k+2,E,d,i+k-e,s,t)
--+    forge(word,w+1,W,entry,e+1,E,d,i,s+1,t)
--+  --check for two consecutive matches down the line
--+  forge(word,w+1,W,entry,e+1,E,d,i,s+1,t)
 
--=======================================================================
--                          String Pattern Matching
--=======================================================================
patternTran pattern ==
  not hasWildCard? pattern and LITER pattern.0 and
    UPCASE copy pattern = pattern =>
      name:= abbreviation? makeSymbol pattern
        or browseError [:bright pattern,
          '"is not a constructor abbreviation"]
      DOWNCASE PNAME name
  maskConvert DOWNCASE pattern
 
hasWildCard? str ==
  or/[stringChar(str,i) = char "?" and
        (i=0 or stringChar(str,i-1) ~= char"__" ) for i in 0..maxIndex str]
 
maskConvert str ==
--replace all ? not preceded by an underscore by &
  buf:= makeString #str
  j:= 0  --index into res
  final := maxIndex str
  for i in 0..final repeat
    c := stringChar(str,i)
    if c = char "__" and i < final then
      i := i+1
      c := stringChar(str,i)
     else if c = char "?" then c := char "&"
    SUFFIX(c,buf)
  buf