source: branches/help/PRIMER_DESIGN/PRD_SearchFIFO.cxx

// =============================================================== //
//                                                                 //
//   File      : PRD_SearchFIFO.cxx                                //
//   Purpose   :                                                   //
//                                                                 //
//   Coded by Wolfram Foerster in February 2001                    //
//   Institute of Microbiology (Technical University Munich)       //
//   http://www.arb-home.de/                                       //
//                                                                 //
// =============================================================== //

#include "PRD_SearchFIFO.hxx"
#include <cmath>

using std::printf;
using std::fabs;

//
// Constructor
//
void SearchFIFO::init(Node *root_, PRD_Sequence_Pos min_distance_to_next_match_, bool expand_IUPAC_Codes_) {
    begin   = NULp;
    end     = NULp;
    current = NULp;

    root                       = root_;
    expand_IUPAC_Codes         = expand_IUPAC_Codes_;
    min_distance_to_next_match = min_distance_to_next_match_;
}

SearchFIFO::SearchFIFO (Node *root_, PRD_Sequence_Pos min_distance_to_next_match_, bool expand_IUPAC_Codes_) {
    init(root_, min_distance_to_next_match_, expand_IUPAC_Codes_);
}

SearchFIFO::SearchFIFO () {
    init(NULp, -1, false);
}


//
// Destructor
//
SearchFIFO::~SearchFIFO () {
    flush();
}


//
// flush : clear FIFO
//
void SearchFIFO::flush () {
    SearchParameter *to_delete;

    current = begin;
    while (current) {
        to_delete = current;
        current   = current->next;
        delete to_delete;
    }

    begin   = NULp;
    end     = NULp;
    current = NULp;
}


//
// append new SearchParameter to the FIFO
//
// the current_node is determined from root with the given base
// multiple parameters are generated for unsure bases like 'N'
//
void SearchFIFO::push (unsigned char base_) {
    unsigned int     bits = CHAR2BIT.FIELD[base_];
    Node            *child_of_root;
    SearchParameter *new_parameter;

    if (bits & 1) {
        child_of_root = root->child[2];   // 2 = A
        if (child_of_root) {
            new_parameter = new SearchParameter;

            new_parameter->node      = child_of_root;
            new_parameter->next      = NULp;
            new_parameter->previous  = end;

            if (end) end->next = new_parameter;
            if (!begin) begin = new_parameter;
            end = new_parameter;
        }
    }

    if (bits & 2) {
        child_of_root = root->child[3];   // 3 = T/U
        if (child_of_root) {
            new_parameter = new SearchParameter;

            new_parameter->node      = child_of_root;
            new_parameter->next      = NULp;
            new_parameter->previous  = end;

            if (end) end->next = new_parameter;
            if (!begin) begin = new_parameter;
            end = new_parameter;
        }
    }

    if (bits & 4) {
        child_of_root = root->child[0];   // 0 = C
        if (child_of_root) {
            new_parameter = new SearchParameter;

            new_parameter->node      = child_of_root;
            new_parameter->next      = NULp;
            new_parameter->previous  = end;

            if (end) end->next = new_parameter;
            if (!begin) begin = new_parameter;
            end = new_parameter;
        }
    }

    if (bits & 8) {
        child_of_root = root->child[1];   // 1 = G
        if (child_of_root) {
            new_parameter = new SearchParameter;

            new_parameter->node      = child_of_root;
            new_parameter->next      = NULp;
            new_parameter->previous  = end;

            if (end) end->next = new_parameter;
            if (!begin) begin = new_parameter;
            end = new_parameter;
        }
    }

}


//
// step down in tree at all the SearchParameters with the given base(s)
//
void SearchFIFO::push_front(Node *child_of_current_) {
    SearchParameter *new_parameter = new SearchParameter;

    new_parameter->node      = child_of_current_;
    new_parameter->next      = begin;
    new_parameter->previous  = NULp;

    if (!end) end             = new_parameter;
    if (begin) begin->previous = new_parameter;
    begin = new_parameter;
}

void SearchFIFO::iterateWith (PRD_Sequence_Pos pos_, unsigned char base_) {
    if (!begin) return;

    current = begin;

    if (!expand_IUPAC_Codes) {
        while (current) {

            // get childnode of parameters current node
            Node *child = current->node->childByBase(base_);

            // erase parameter if child doesn't exist
            if (!child) {
                erase(current);
            }
            else {
                // step down as child exists
                current->node = child;

                // invalidate if node is primer and is in range
                if (child->isValidPrimer()) {
                    if (min_distance_to_next_match <= 0) {
                        child->last_base_index = -pos_;
                    }
                    else {
                        if (min_distance_to_next_match >= fabs(double(pos_ - child->last_base_index))) child->last_base_index = -pos_;
                    }
                }

                // erase parameter if child is leaf
                if (child->isLeaf()) {
                    erase(current);

                    // erase node in tree if leaf and invalid primer
                    if (!child->isValidPrimer()) {
                        // remove child from parent
                        child->parent->child[CHAR2CHILD.INDEX[base_]] = NULp;
                        child->parent->child_bits &= ~CHAR2BIT.FIELD[base_];
                        // erase node
                        delete child;
                    }
                }
            }

            // next parameter (or begin if erase killed current while pointing to begin)
            current = current ? current->next : begin;
        }
    }
    else { // expand IUPAC-Codes
        while (current) {
            int bits = current->node->child_bits & CHAR2BIT.FIELD[base_];

            if (bits & 1) {   // A
                Node *child = current->node->child[2];   // 2 = A

                // invalidate if node is primer and is in range
                if (child->isValidPrimer()) {
                    if (min_distance_to_next_match <= 0) {
                        child->last_base_index = -pos_;
                    }
                    else {
                        if (min_distance_to_next_match >= fabs(double(pos_ - child->last_base_index))) child->last_base_index = -pos_;
                    }
                }

                // erase child if child is leaf
                if (child->isLeaf()) {
                    // erase node in tree if leaf and invalid primer
                    if (!child->isValidPrimer()) {
                        // remove child from parent
                        child->parent->child[CHAR2CHILD.INDEX[base_]] = NULp;
                        child->parent->child_bits &= ~CHAR2BIT.FIELD[base_];
                        // erase node
                        delete child;
                    }
                }
                else { // add new parameter at the begin of fifo
                    push_front(child);
                }
            }

            if (bits & 2) {   // T/U
                Node *child = current->node->child[3];   // 3 = T/U

                // invalidate if node is primer and is in range
                if (child->isValidPrimer()) {
                    if (min_distance_to_next_match <= 0) {
                        child->last_base_index = -pos_;
                    }
                    else {
                        if (min_distance_to_next_match >= fabs(double(pos_ - child->last_base_index))) child->last_base_index = -pos_;
                    }
                }

                // erase child if child is leaf
                if (child->isLeaf()) {
                    // erase node in tree if leaf and invalid primer
                    if (!child->isValidPrimer()) {
                        // remove child from parent
                        child->parent->child[CHAR2CHILD.INDEX[base_]] = NULp;
                        child->parent->child_bits &= ~CHAR2BIT.FIELD[base_];
                        // erase node
                        delete child;
                    }
                }
                else { // add new parameter at the begin of fifo
                    push_front(child);
                }
            }

            if (bits & 4) {   // C
                Node *child = current->node->child[0];   // 0 = C

                // invalidate if node is primer and is in range
                if (child->isValidPrimer()) {
                    if (min_distance_to_next_match <= 0) {
                        child->last_base_index = -pos_;
                    }
                    else {
                        if (min_distance_to_next_match >= fabs(double(pos_ - child->last_base_index))) child->last_base_index = -pos_;
                    }
                }

                // erase child if child is leaf
                if (child->isLeaf()) {
                    // erase node in tree if leaf and invalid primer
                    if (!child->isValidPrimer()) {
                        // remove child from parent
                        child->parent->child[CHAR2CHILD.INDEX[base_]] = NULp;
                        child->parent->child_bits &= ~CHAR2BIT.FIELD[base_];
                        // erase node
                        delete child;
                    }
                }
                else { // add new parameter at the begin of fifo
                    push_front(child);
                }
            }

            if (bits & 8) {   // G
                Node *child = current->node->child[1];   // 1 = G

                // invalidate if node is primer and is in range
                if (child->isValidPrimer()) {
                    if (min_distance_to_next_match <= 0) {
                        child->last_base_index = -pos_;
                    }
                    else {
                        if (min_distance_to_next_match >= fabs(double(pos_ - child->last_base_index))) child->last_base_index = -pos_;
                    }
                }

                // erase child if child is leaf
                if (child->isLeaf()) {
                    // erase node in tree if leaf and invalid primer
                    if (!child->isValidPrimer()) {
                        // remove child from parent
                        child->parent->child[CHAR2CHILD.INDEX[base_]] = NULp;
                        child->parent->child_bits &= ~CHAR2BIT.FIELD[base_];
                        // erase node
                        delete child;
                    }
                }
                else { // add new parameter at the begin of fifo
                    push_front(child);
                }
            }

            // erase old parameter
            erase(current);

            // next parameter (or begin if erase killed current while pointing to begin)
            current = current ? current->next : begin;
        }
    }
}


//
// erase given parameter while not invalidating current
//
void SearchFIFO::erase (SearchParameter *param_) {
    // unlink from doublelinked list
    if (param_->next) param_->next->previous = param_->previous; else end   = param_->previous;
    if (param_->previous) param_->previous->next = param_->next;       else begin = param_->next;

    // set current to current->previous if current is to delete
    if (param_ == current) current = param_->previous;

    delete param_;
}


//
// print positions-list
//
void SearchFIFO::print () {
    current = begin;
    if (begin)
        printf("print : begin %p (%p[%c],%p,%p)\t", begin, begin->node, begin->node->base, begin->previous, begin->next);
    else
        printf("print : begin (nil)\n");

    if (end)
        printf("end %p (%p[%c],%p,%p)\n", end, end->node, end->node->base, end->previous, end->next);
    else
        printf("end (nil)\n");

    while (current) {
        printf("print : %p (%p[%c],%p,%p)\n", current, current->node, current->node->base, current->previous, current->next);
        current = current->next;
    }
}