#!/usr/bin/python3
import json
import os
import subprocess
import sys
import time

import ox
from .pi import random
from .render_kdenlive import KDEnliveProject


def random_choice(seq, items, pop=False):
    n = n_ = len(items) - 1
    #print('len', n)
    if n == 0:
        if pop:
            return items.pop(n)
        return items[n]
    r = seq()
    base = 10
    while n > 10:
        n /= 10
        #print(r)
        r += seq()
        base += 10
    r = int(n_ * r / base)
    #print('result', r, items)
    if pop:
        return items.pop(r)
    return items[r]

def chance(seq, chance):
    return (seq() / 10) >= chance


def compose(clips, target=150, base=1024):
    length = 0
    scene = {
        'front': {
            'V1': [],
            'V2': [],
        },
        'back': {
            'V1': [],
            'V2': [],
        },
        'audio': {
            'A1': [],
            'A2': [],
            'A3': [],
            'A4': [],
        }
    }
    all_clips = clips.copy()
    seq = random(base)
    while target - length > 10 and clips:
        clip = random_choice(seq, clips, True)
        if not clips:
            clips = [c for c in all_clips if c != clip]
        if length + clip['duration'] > target:
            break
        length += clip['duration']

        fg = clip['foreground']
        if 'foreground2' in clip:
            if chance(seq, 0.5):
                fg = clip['foreground2']

        scene['front']['V1'].append({
            'duration': clip['duration'],
            'src': fg,
            "filter": {
                'transparency': seq() / 10,
            }
        })

        transparency = seq() / 10
        # coin flip which site is visible (50% chance)
        if chance(seq, 0.5):
            transparency_front = transparency
            transparency_back = 0
        else:
            transparency_back = transparency
            transparency_front = 0
        scene['front']['V2'].append({
            'duration': clip['duration'],
            'src': clip['background'],
            "filter": {
                'transparency': transparency_front
            }
        })
        scene['back']['V1'].append({
            'duration': clip['duration'],
            'src': clip['background'],
            "filter": {
                'transparency': transparency_back
            }
        })
        scene['back']['V2'].append({
            'duration': clip['duration'],
            'src': clip['original'],
            "filter": {
                'transparency': seq() / 10,
            }
        })
        # 50 % chance to blur original from 0 to 30
        if chance(seq, 0.5):
            blur = seq() * 3
            if blur:
                scene['back']['V2'][-1]['filter']['blur'] = blur
        scene['audio']['A1'].append({
            'duration': clip['duration'],
            'src': clip['original'],
        })
        scene['audio']['A2'].append({
            'duration': clip['duration'],
            'src': fg,
        })
    return scene


def render(root, scene, prefix=''):
    fps = 24
    files = []
    for timeline, data in scene.items():
        print(timeline)
        project = KDEnliveProject(root)

        tracks = []
        for track, clips in data.items():
            print(track)
            for clip in clips:
                project.append_clip(track, clip)
        path = os.path.join(root, prefix + "%s.kdenlive" % timeline)
        with open(path, 'w') as fd:
            fd.write(project.to_xml())
        files.append(path)
    return files