hatemap = { }

local function OnNPCKilled( npc, attacker, inflictor )
    local a, b, k, v, d

    a = npc:GetClass( )
    b = attacker:GetClass( )

    hatemap[ a ] = hatemap[ a ] or { }
    hatemap[ a ][ b ] = hatemap[ a ][ b ] or 0

    hatemap[ b ] = hatemap[ b ] or { }
    hatemap[ b ][ a ] = hatemap[ b ][ a ] or 0

    hatemap[ a ][ b ] = hatemap[ a ][ b ] - 100
    hatemap[ b ][ a ] = hatemap[ b ][ a ] + 100

    d = hatemap[ a ][ b ]

    for k, v in ents.FindByClass( a ) do
        v:AddRelationship( string.format( "%s %s %d", b, d > 0 and "D_LI" or "D_HT", math.abs( d ) ) )
        if d > 0 then
            v:AddRelationship( string.format( "%s D_HT 0", b ) )
        end
    end

    d = hatemap[ b ][ a ]

    for k, v in ents.FindByClass( b ) do
        v:AddRelationship( string.format( "%s %s %d", b, d > 0 and "D_LI" or "D_HT", math.abs( d ) )
        if d > 0 then
            v:AddRelationship( string.format( "%s D_HT 0", b ) )
        end
    end
end

local function EntityTakeDamage( ent, inflictor, attacker, amount, info )
    local a, b

    if not ( ent:IsPlayer( ) or ent:IsNPC( ) ) then
        return
    end

    a = ent:GetClass( )
    b = attacker:GetClass( )

    hatemap[ a ] = hatemap[ a ] or { }
    hatemap[ a ][ b ] = hatemap[ a ][ b ] or 0

    hatemap[ b ] = hatemap[ b ] or { }
    hatemap[ b ][ a ] = hatemap[ b ][ a ] or 0

    hatemap[ a ][ b ] = hatemap[ a ][ b ] - amount
    hatemap[ b ][ a ] = hatemap[ b ][ a ] + amount

    d = hatemap[ a ][ b ]

    for k, v in ents.FindByClass( a ) do
        v:AddRelationship( string.format( "%s %s %d", b, d > 0 and "D_LI" or "D_HT", math.abs( d ) ) )
        if d > 0 then
            v:AddRelationship( string.format( "%s D_HT 0", b ) )
        end
    end

    d = hatemap[ b ][ a ]

    for k, v in ents.FindByClass( b ) do
        v:AddRelationship( string.format( "%s %s %d", b, d > 0 and "D_LI" or "D_HT", math.abs( d ) )
        if d > 0 then
            v:AddRelationship( string.format( "%s D_HT 0", b ) )
        end
    end
end

local function OnEntityCreated( ent )
    local a, k, v

    a = ent:GetClass( )

    if hatemap[ a ] and ent:IsNPC( ) then
        for k, v in pairs( hatemap[ a ] ) do
            ent:AddRelationship( string.format( "%s %s %d", k, v > 0 and "D_LI" or "D_HT", v ) )
        end
    end
end

hook.Add( "OnNPCKilled", "Hatemap.OnNPCKilled", OnNPCKilled )
hook.Add( "EntityTakeDamage", "Hatemap.EntityTakeDamage", EntityTakeDamage )
hook.Add( "OnEntityCreated", "Hatemap.OnEntityCreated", OnEntityCreated )