#include <stdint.h>
#include <stdlib.h>
#include "stack.h"

Stack* CreateStack()
{
    int32_t i;
    Stack *stack = (Stack*) malloc(sizeof(Stack));
    stack->stackCapacity = 4;
    stack->stackFrames = (StackFrame*) malloc(sizeof(StackFrame) * stack->stackCapacity);
    for (i = 0; i < stack->stackCapacity; i += 1)
    {
        stack->stackFrames[i].nodes = NULL;
        stack->stackFrames[i].nodeCapacity = 0;
        stack->stackFrames[i].nodeCount = 0;
    }
    stack->stackIndex = 0;

    PushStackFrame(stack);
    return stack;
}

void PushStackFrame(Stack *stack)
{
    stack->stackIndex += 1;

    if (stack->stackIndex == stack->stackCapacity)
    {
        stack->stackCapacity += 1;
        stack->stackFrames = (StackFrame*) realloc(stack->stackFrames, sizeof(StackFrame) * stack->stackCapacity);
        stack->stackFrames[stack->stackIndex].nodes = NULL;
        stack->stackFrames[stack->stackIndex].nodeCapacity = 0;
        stack->stackFrames[stack->stackIndex].nodeCount = 0;
    }

    stack->stackFrames[stack->stackIndex].nodeCount = 0;
}

void PopStackFrame(Stack *stack)
{
    stack->stackIndex -= 1;
}

void AddNode(Stack *stack, Node *statementNode)
{
    StackFrame *stackFrame = &stack->stackFrames[stack->stackIndex];
    if (stackFrame->nodeCount == stackFrame->nodeCapacity)
    {
        stackFrame->nodeCapacity += 1;
        stackFrame->nodes = (Node**) realloc(stackFrame->nodes, sizeof(Node*) * stackFrame->nodeCapacity);
    }
    stackFrame->nodes[stackFrame->nodeCount] = statementNode;
    stackFrame->nodeCount += 1;
}

Node** GetNodes(Stack *stack, uint32_t *pCount)
{
    if (stack->stackIndex < 0) {
        *pCount= 0;
        return NULL;
    }

    *pCount = stack->stackFrames[stack->stackIndex].nodeCount;
    return stack->stackFrames[stack->stackIndex].nodes;
}