library Pool

globals
    hashtable     HASH = InitHashtable()
    integer array VALUES
    real    array WEIGHT_META
    integer array META
endglobals

function POOL_NEW takes nothing returns integer
    local integer I = META[0]
    
    if I > 0 then
        set META[0] = META[META[0]]
    else
        if I == -64 then
            return F_NULL
        endif
        set META[0] = META[0] - 1
        set I = -META[0]
    endif
    
    set META[I] = -1
    return I
endfunction

function POOL_REM takes integer I returns nothing
    if META[I] != -1 then
        return
    endif
    set META[I] = META[0]
    set META[0] = I
    set META[127*I - 63 + 1] = 0
    set META[127*I - 63 + 2] = 0
endfunction

function POOL_ADD_INT takes integer POOL, integer VALUE, real WEIGHT returns nothing
    local integer TMP
    
    if META[POOL] != -1 or META[127*POOL -63 +1] == 127 then
        return
    endif
    
    set TMP = LoadInteger(HASH, POOL, VALUE)
    if TMP == 0 then
        set META[127*POOL -63 +1] = META[127*POOL -63 +1] +1
        set TMP    = 128*(POOL-1) + META[127*POOL -63 +1]
        call SaveInteger(HASH, POOL, VALUE, TMP)
        set VALUES[TMP] = VALUE
    endif
    if WEIGHT <= 0.0 then
        set META[127*POOL -63 +2] = 1
        return
    endif
    set WEIGHT_META[128*(POOL-1)] = WEIGHT_META[128*(POOL-1)] +WEIGHT -WEIGHT_META[TMP]
    set WEIGHT_META[TMP] = WEIGHT    
    
endfunction

function POOL_REM_INT takes integer POOL, integer VALUE returns nothing
    
    local integer I = LoadInteger(HASH, POOL, VALUE)
    
    if I == 0 then
        return
    endif
    
    call RemoveSavedInteger(HASH, POOL, VALUE)    
    set WEIGHT_META[128*(POOL-1)] = WEIGHT_META[128*(POOL-1)] -WEIGHT_META[I]
    
    set VALUES[I]                 =      VALUES[128*(POOL-1) +META[127*POOL -63 +1]]
    set WEIGHT_META[I]            = WEIGHT_META[128*(POOL-1) +META[127*POOL -63 +1]]
    
    call SaveInteger(HASH,POOL,VALUES[I],I)
    set META[127*POOL -63 +1] = META[127*POOL -63 +1] - 1
    
endfunction

function POOL_REM_LST takes integer POOL returns integer
    
    if META[127*POOL -63 +1] == 0 then
        return F_NULL
    endif
        
    call RemoveSavedInteger(HASH, POOL, VALUES[META[127*POOL -63 +1] +128*(POOL-1)])
    
    set WEIGHT_META[128*(POOL-1)] = WEIGHT_META[128*(POOL-1)] -WEIGHT_META[META[127*POOL -63 +1] +128*(POOL-1)]
    set META[127*POOL -63 +1] = META[127*POOL -63 +1] - 1
    
    return VALUES[META[127*POOL -63 +1] + 128*(POOL-1) + 1]
        
endfunction 

function POOL_RND_INT takes integer POOL returns integer
    local real    RANDOM = 0
    local integer OFFSET = 128*(POOL-1)
    
    if META[127*POOL -63 +1] == 0 then
        return F_NULL
    endif
    
    if META[127*POOL - 63 + 2] != 0 then
        set OFFSET = GetRandomInt(1,META[127*POOL -63 +1]) + OFFSET
        return VALUES[OFFSET]
    else
        set RANDOM = GetRandomReal(0,WEIGHT_META[OFFSET])
        loop
            set OFFSET = OFFSET + 1
            set RANDOM = RANDOM - WEIGHT_META[OFFSET]
            exitwhen RANDOM <= 0
        endloop
        
        return VALUES[OFFSET]
    endif
    
endfunction

function POOL_COPY takes integer POOL returns integer
    local integer A = POOL_NEW()
    local integer B = META[127*POOL - 63 + 1]
    
    if META[POOL] != -1 or A == F_NULL then
        return F_NULL
    endif
    
    set META[127*A - 63 + 2]   = META[127*POOL - 63 + 2]
    set WEIGHT_META[128*(A-1)] = WEIGHT_META[128*(POOL-1)]
    set META[127*A - 63 + 1]   = META[127*POOL - 63 + 1]
    
    loop
        set VALUES     [128*(A-1) + B] = VALUES     [128*(POOL-1) + B]
        set WEIGHT_META[128*(A-1) + B] = WEIGHT_META[128*(POOL-1) + B]
        call SaveInteger(HASH, A, VALUES[128*(POOL-1) + B], 128*(A-1) + B)
        set B = B - 1
        exitwhen B == 0
    endloop
    
    return A
    
endfunction

function VALUE_WEIGHT takes integer POOL, integer VALUE returns real
    return WEIGHT_META[LoadInteger(HASH, POOL, VALUE)]
endfunction

function VALUE_CHANCE takes integer POOL, integer VALUE returns real
    if WEIGHT_META[128*(POOL-1)] > 0. then
        return WEIGHT_META[LoadInteger(HASH, POOL, VALUE)]/WEIGHT_META[128*(POOL-1)]
    endif
    return 0.
endfunction

endlibrary

local integer A = POOL_NEW()
    local integer B = 0
    local integer C = 0
    
    call POOL_ADD_INT(A,'Hpal',10 )
    call POOL_ADD_INT(A,'Hamg',10 )
    call POOL_ADD_INT(A,'Hmkg',10 )
    call POOL_ADD_INT(A,'Hblm',0.1)
    
    set B = POOL_COPY(A)
    
    loop
        set C = POOL_RND_INT(A)
        call POOL_REM_INT(A,C)
        call CreateUnit(Player(0),C,0.0,0.0,270.0)
        exitwhen C == F_NULL
    endloop
    
    loop
        set C = POOL_RND_INT(B)
        call POOL_REM_INT(B,C)
        call CreateUnit(Player(0),C,0.0,0.0,270.0)
        exitwhen C == F_NULL
    endloop