#include <u.h>
#include <libn.h>
#include <libbio.h>

// -----------------------------------------------------------------------
// subtree manipulation methods

error
phylo·addchild(bio·Node* parent, bio·Node* child)
{
    bio·Node *it, *sibling;
    switch (parent->nchild) {
    case 1:
        parent->child[0]->sibling = child;
    case 0:
        parent->child[parent->nchild++] = child;
    break;

    default:
        sibling = parent->child[1];
        for (it = parent->child[1]->sibling; it != nil; it = it->sibling) {
            sibling = it;
        }
        sibling->sibling = child;
        parent->nchild++;
    }

    child->parent = parent;
    return 0;
}

error
phylo·rmchild(bio·Node* parent, bio·Node* child)
{
    bio·Node *it, *prev;
    enum {
        error·nil,
        error·notfound,
    };

    prev = nil;
    for (it = parent->child[0]; it != nil && it != child; it = it->sibling) {
        prev = it;
    }
    if (it == nil) return error·notfound;



    return error·nil;
}

// -----------------------------------------------------------------------
// subtree statistics

error
phylo·countnodes(bio·Node *node, int *n)
{
    error     err;
    bio·Node *child;
    
    *n += 1;
    for (child = node->child[0]; child != nil; child = child->sibling) {
        if (err = phylo·countnodes(child, n), err) {
            errorf("node count: failure at '%s'", child->name);
            return 1;
        }
    }

    return 0;
}

error
phylo·countleafs(bio·Node *node, int *n)
{
    error     err;
    bio·Node *child;
    
    if (!node->nchild) {
        *n += 1;
    }

    for (child = node->child[0]; child != nil; child = child->sibling) {
        if (err = phylo·countleafs(child, n), err) {
            errorf("leaf count: failure at '%s'", child->name);
            return 1;
        }
    }

    return 0;
}

// -----------------------------------------------------------------------
// tree editing

error
phylo·ladderize(bio·Node *root)
{
    int       i;
    error     err;
    bio·Node *child;
    double    dists[50];

    if (!root->nchild) return 0;
    Assert(root->nchild < arrlen(dists));

    for (i = 0, child = root->child[0]; child != nil; child = child->sibling, i++) {
        if (err = phylo·ladderize(child), err) {
            errorf("ladderize: failure at '%s'", child->name);
            return 1;
        }
        dists[i] = child->dist;
    }

    return 0;
}