//
// Created by jedi on 11/5/18.
//

#include "node.h"
#include "gfx/layout.h"

void layout::render() {
    for (int j = 0; j < allocated_; j++) {
        node *node_ptr;
        if (node_ptr = slots[j].content) {
            slots[j].canvas_->clear();
            node_ptr->render(*slots[j].canvas_);
            screen_.draw(slots[j].pos_, 0, *slots[j].canvas_);
        }
    }
}

int layout::apply(node* node) {
    int rootslot = allocate_(node, maxslots);
    int minsize = pack_(rootslot + 1);
    expand_(minsize);
    if (cursor == nullptr)
        cursor = slots[rootslot].content->getCursor();
    return 0;
}

int layout::pack_(int usedslots) {
    int minsum = 0;
    int i;
    for (i = 0; i < usedslots; i++) {
        if (!slots[i].content) break;
        if (minsum + slots[i].content->minsize > maxwidth_) break;
        minsum += slots[i].content->minsize;
    }
    allocated_ = i;
    return minsum;
}

int layout::expand_(int packedsize) {
    int diff = maxwidth_ - packedsize;
    int pos = 0;
    for (int i = allocated_ - 1; i >= 0; i--) {
        slots[i].pos_ = pos;
        int size = slots[i].content->minsize + (diff * slots[i].content->minsize) / packedsize;
        if (size > slots[i].content->maxsize)
            size = slots[i].content->maxsize;
        slots[i].size_ = size;
        if(slots[i].canvas_)
            delete slots[i].canvas_;
        slots[i].canvas_ = new canvas(size, maxheight_);
        pos += size;
    }
    return 0;
}

int layout::allocate_(node* current, int depth) {
    if (node* next = current->getCursor()) {
        int i = allocate_(next, depth) + 1;
        slots[i].content = current;
        return i;
    } else {
        slots[0].content = current;
        return 0;
    }
}