#!/usr/bin/env python

from __future__ import division
import ipdb
import os
import random
import sys
import time

import parse
import topsort
import yaml

        for subsection in ["intro", "body", "outro"]:
            try:
                print "; Subsection " + subsection
                subsection = section[subsection]

                unordered_instrs = []
                for instr in subsection:
                    subsection[instr]["name"] = instr
                    if not "sync" in subsection[instr].keys():
                        subsection[instr]["sync"] = None
                    unordered_instrs.append([subsection[instr]["sync"], instr])
                ordered_instrs = topsort.topsort(unordered_instrs)
                ordered_instrs.remove(None)  # None used as a placeholder for sort order for instruments with no sync setting

                instrs = []
                syncs = {}
                for instr in ordered_instrs:
                    print ";Instrument " + instr
                    instr = subsection[instr]

                    max_time = instr["duration"]
                    instr_score, syncs = render_instr(instr, syncs, max_time)
                    instrs.append(instr_score)
                    for line in generate_csound_score(instr_score, instr["score_line"], subsection_start):
                        print line
                longest_score = max(instrs, key=lambda i: score_len(i))
                subsection_start += score_len(longest_score)
                section_start += score_len(longest_score)
            except KeyError:
                pass


def render_instr(instr, syncs, max_time):
    for g in instr["grammars"]:
        for i in range(len(instr["grammars"][g])):
            instr["grammars"][g][i] = parse.parse(instr["grammars"][g][i])

    score= []



    try:
        score, syncs = choose_phrase(instr, syncs, 0, max_time)




        while True:
            score_index_to_replace = None
            for item in range(len(score)):  # Optimize this by caching the index of the last node I replaced and startng there
                if isinstance(score[item], tree.Tree):
                    score_index_to_replace = item
            if score_index_to_replace is None:
                raise ValueError("No more nodes to fill in")

            time_remaining = max_time - score_len(score)
            new_phrase, syncs = choose_phrase(instr, syncs, score_len(score), time_remaining)


            score = score[:node_index-1] + new_phrase + score[node_index+1:]














    except ValueError:
        return (score, syncs)


def choose_phrase(instr, syncs, current_time, time_remaining):
    '''Filters grammars for ones that match the sync option, and phrases that fit the time remaining in the score'''
    time_filtered_grammars = {}
    for grammar in instr["grammars"]:
        time_filtered_grammars[grammar] = get_phrases_that_fit(instr["grammars"][grammar], time_remaining)
    if len(time_filtered_grammars.keys()) == 0:
        raise ValueError("No available grammars that will fit in the score")

    grammar = None
#    if instr["name"] == "follow_instr":
#        ipdb.set_trace()


    if instr["sync"] is not None:
        guiding_instr = instr["sync"]
        sync_node = get_sync_node_at_time(syncs[guiding_instr], current_time)
        if sync_node in time_filtered_grammars.keys():
            grammar = sync_node
    if grammar is None:
        grammar = random.choice(time_filtered_grammars.keys())
    phrases = time_filtered_grammars[grammar]
    if instr["name"] not in syncs.keys():
        syncs[instr["name"]] = []
    syncs[instr["name"]].append({"node": grammar, "time": current_time})

    return random.choice(phrases), syncs


def get_phrases_that_fit(grammar, time_remaining):
    valid_phrases = []
    for phrase in grammar:
        if score_len(phrase) <= time_remaining:
            valid_phrases.append(phrase)


    return valid_phrases


def get_sync_node_at_time(syncs, t):
    for s in range(len(syncs)):
        if syncs[s]["time"] >= t:
            return syncs[s]["node"]


def score_len(score):
    total = 0
    for n in score:
        if not isinstance(n, tree.Tree):