#!/usr/bin/python3
import json
import os
import subprocess
import sys
import time
import shutil
from pathlib import Path

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


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 get_clip_by_seqid(clips, seqid):
    selected = None
    for i, clip in enumerate(clips):
        if clip['seqid'] == seqid:
            selected = i
            break
    if selected is not None:
        return clips.pop(i)
    return None


def compose(clips, target=150, base=1024, voice_over=None):
    length = 0
    scene = {
        'front': {
            'V1': [],
            'V2': [],
        },
        'back': {
            'V1': [],
            'V2': [],
        },
        'audio': {
            'A1': [],
            'A2': [],
            'A3': [],
            'A4': [],
        }
    }
    all_clips = clips.copy()
    seq = random(base)

    voice_overs = []
    if voice_over:
        vo_keys = list(voice_over)
        if chance(seq, 0.5):
            voice_overs.append(voice_over[vo_keys[chance(seq, len(vo_keys))]])
        elif len(vo_keys) >= 2:
            vo1 = vo_keys.pop(chance(seq, len(vo_keys)))
            vo2 = vo_keys.pop(chance(seq, len(vo_keys)))
            voice_overs.append(voice_over[vo1])
            if voice_over[vo1]["duration"] + voice_over[vo2]["duration"] < target:
                voice_overs.append(voice_over[vo2])
        vo_min = sum([vo['duration'] for vo in voice_overs])
        if vo_min > target:
            target = vo_min
        elif vo_min < target:
            offset = (target - vo_min) / 2
            scene['audio']['A3'].append({
                'blank': True,
                'duration': offset
            })
            vo_min += offset
        for vo in voice_overs:
            scene['audio']['A3'].append(vo)

    clip = None
    while target - length > 0 and clips:
        # coin flip which site is visible (50% chance)
        if length:
            remaining = target - length
            remaining = remaining * 1.05  # allow for max of 10% over time
            clips = [c for c in clips if c['duration'] <= remaining]
            if not clips:
                break
        if clip:
            if chance(seq, 0.5):
                next_seqid = clip['seqid'] + 1
                clip = get_clip_by_seqid(clips, next_seqid)
            else:
                clip = None
        if not clip:
            clip = random_choice(seq, clips, True)
        if not clips:
            clips = [c for c in all_clips if c != clip]
            if not clips:
                clips = all_clips.copy()
        if length + clip['duration'] > target and length >= vo_min:
            break
        print('%06.3f %06.3f' % (length, clip['duration']), os.path.basename(clip['original']))
        length += clip['duration']

        if "foreground" not in clip and "animation" in clip:
            fg = clip['animation']
            transparancy = 1
        else:
            fg = clip['foreground']
            if 'foreground2' in clip:
                if 'foreground3' in clip:
                    n = seq()
                    if n <= 3:  # 0,1,2,3
                        clip['foreground']
                    elif n <= 6:  # 4,5,6
                        clip['foreground2']
                    else:  # 7,8,9
                        clip['foreground3']
                elif chance(seq, 0.5):
                    fg = clip['foreground2']
            transparancy = seq() / 10
        if 'foley' in clip:
            foley = clip['foley']
        else:
            foley = fg
        scene['front']['V2'].append({
            'duration': clip['duration'],
            'src': fg,
            "filter": {
                'transparency': transparancy,
            }
        })

        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
        transparency_original = seq() / 10
        if "background" in clip:
            scene['front']['V1'].append({
                'duration': clip['duration'],
                'src': clip['background'],
                "filter": {
                    'transparency': transparency_front
                }
            })
            scene['back']['V2'].append({
                'duration': clip['duration'],
                'src': clip['background'],
                "filter": {
                    'transparency': transparency_back
                }
            })
        else:
            scene['front']['V1'].append({
                'duration': clip['duration'],
                'src': clip['animation'],
                "filter": {
                    'transparency': 0,
                }
            })
            scene['back']['V2'].append({
                'duration': clip['duration'],
                'src': clip['original'],
                "filter": {
                    'transparency': 0,
                }
            })

        scene['back']['V1'].append({
            'duration': clip['duration'],
            'src': clip['original'],
            "filter": {
                'transparency': transparency_original,
            }
        })
        # 50 % chance to blur original from 0 to 30
        if chance(seq, 0.5):
            blur = seq() * 3
            if blur:
                scene['back']['V1'][-1]['filter']['blur'] = blur
        scene['audio']['A1'].append({
            'duration': clip['duration'],
            'src': clip['original'],
        })
        # TBD: Foley
        scene['audio']['A2'].append({
            'duration': clip['duration'],
            'src': foley,
        })
    print("scene duration %0.3f (target: %0.3f)" % (length, target))
    return scene

def get_scene_duration(scene):
    duration = 0
    for key, value in scene.items():
        for name, clips in value.items():
            for clip in clips:
                duration += clip['duration']
            return duration

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)
        if timeline == "audio":
            duration = project.get_duration()
            for track, clips in data.items():
                project = KDEnliveProject(root)
                for clip in clips:
                    project.append_clip(track, clip)
                track_duration = project.get_duration()
                delta = duration - track_duration
                if delta > 0:
                    project.append_clip(track, {'blank': True, "duration": delta/24})
                path = os.path.join(root, prefix + "%s-%s.kdenlive" % (timeline, track))
                with open(path, 'w') as fd:
                    fd.write(project.to_xml())
                files.append(path)
    return files

def get_fragments(clips, voice_over):
    import itemlist.models
    import item.models
    from collections import defaultdict

    fragments = []

    for l in itemlist.models.List.objects.filter(status='featured').order_by('name'):
        if l.name.split(' ')[0].isdigit():
            fragment = {
                'name': l.name,
                'tags': [t['value'] for t in l.query['conditions'][1]['conditions']],
                'description': l.description
            }
            fragment["id"] = int(fragment['name'].split(' ')[0])
            fragment['clips'] = []
            for clip in clips:
                if set(clip['tags']) & set(fragment['tags']):
                    fragment['clips'].append(clip)
            fragment["voice_over"] = voice_over.get(str(fragment["id"]), {})
            fragments.append(fragment)
    fragments.sort(key=lambda f: ox.sort_string(f['name']))
    return fragments


def render_all(options):
    prefix = options['prefix']
    duration = int(options['duration'])
    base = int(options['offset'])

    _cache = os.path.join(prefix, "cache.json")
    if os.path.exists(_cache):
        with open(_cache) as fd:
            _CACHE.update(json.load(fd))

    with open(os.path.join(prefix, "clips.json")) as fd:
        clips = json.load(fd)
    with open(os.path.join(prefix, "voice_over.json")) as fd:
        voice_over = json.load(fd)
    fragments = get_fragments(clips, voice_over)
    with open(os.path.join(prefix, "fragments.json"), "w") as fd:
        json.dump(fragments, fd, indent=2, ensure_ascii=False)
    position = target_position = 0
    target = fragment_target = duration / len(fragments)
    base_prefix = os.path.join(prefix, 'render', str(base))
    for fragment in fragments:
        fragment_id = int(fragment['name'].split(' ')[0])
        name = fragment['name'].replace(' ', '_')
        if fragment_id < 10:
            name = '0' + name
        if not fragment['clips']:
            print("skipping empty fragment", name)
            continue
        fragment_prefix = os.path.join(base_prefix, name)
        os.makedirs(fragment_prefix, exist_ok=True)

        scene = compose(fragment['clips'], target=target, base=base, voice_over=fragment['voice_over'])
        scene_duration = get_scene_duration(scene)
        print("%s %6.3f -> %6.3f (%6.3f)" % (name, target, scene_duration, fragment_target))
        position += scene_duration
        target_position += fragment_target
        if position > target_position:
            target = fragment_target - (position-target_position)
            print("adjusting target duration for next fragment: %6.3f -> %6.3f" % (fragment_target, target))
        elif position < target_position:
            target = target + 0.1 * fragment_target

        timelines = render(prefix, scene, fragment_prefix[len(prefix) + 1:] + '/')

        with open(os.path.join(fragment_prefix, 'scene.json'), 'w') as fd:
            json.dump(scene, fd, indent=2, ensure_ascii=False)

        if not options['no_video']:
            for timeline in timelines:
                print(timeline)
                ext = '.mp4'
                if '/audio' in timeline:
                    ext = '.wav'
                cmd = [
                    'xvfb-run', '-a',
                    'melt', timeline,
                    '-quiet',
                    '-consumer', 'avformat:%s' % timeline.replace('.kdenlive', ext),
                ]
                if ext == '.wav':
                    cmd += ['vn=1']
                else:
                    cmd += ['an=1', 'vcodec=libx264', 'x264opts=keyint=1', 'crf=15']
                subprocess.call(cmd)
                if ext == '.wav' and timeline.endswith('audio.kdenlive'):
                    cmd = [
                        'ffmpeg', '-y',
                        '-nostats', '-loglevel', 'error',
                        '-i',
                        timeline.replace('.kdenlive', ext),
                        timeline.replace('.kdenlive', '.mp4')
                    ]
                    subprocess.call(cmd)
                    os.unlink(timeline.replace('.kdenlive', ext))

            fragment_prefix = Path(fragment_prefix)
            cmds = []
            for src, out1, out2 in (
                ("audio-A1.wav", "fl.wav", "fr.wav"),
                ("audio-A2.wav", "fc.wav", "lfe.wav"),
                ("audio-A3.wav", "bl.wav", "br.wav"),
            ):
                cmds.append([
                    "ffmpeg", "-y",
                    "-nostats", "-loglevel", "error",
                    "-i", fragment_prefix / src,
                    "-filter_complex",
                    "[0:0]pan=1|c0=c0[left]; [0:0]pan=1|c0=c1[right]",
                    "-map", "[left]", fragment_prefix / out1,
                    "-map", "[right]", fragment_prefix / out2,
                ])
            cmds.append([
                "ffmpeg", "-y",
                "-nostats", "-loglevel", "error",
                "-i", fragment_prefix / "fl.wav",
                "-i", fragment_prefix / "fr.wav",
                "-i", fragment_prefix / "fc.wav",
                "-i", fragment_prefix / "lfe.wav",
                "-i", fragment_prefix / "bl.wav",
                "-i", fragment_prefix / "br.wav",
                "-filter_complex", "[0:a][1:a][2:a][3:a][4:a][5:a]amerge=inputs=6[a]",
                "-map", "[a]", "-c:a", "aac", fragment_prefix / "audio-5.1.mp4"
            ])
            cmds.append([
                "ffmpeg", "-y",
                "-nostats", "-loglevel", "error",
                "-i", fragment_prefix / "back.mp4",
                "-i", fragment_prefix / "audio-5.1.mp4",
                "-c", "copy",
                fragment_prefix / "back-5.1.mp4",
            ])
            for cmd in cmds:
                #print(" ".join([str(x) for x in cmd]))
                subprocess.call(cmd)
            shutil.move(fragment_prefix / "back-5.1.mp4", fragment_prefix / "back.mp4")
            for fn in (
                "audio-5.1.mp4", "fl.wav", "fr.wav", "fc.wav", "lfe.wav", "bl.wav", "br.wav",
            ):
                fn = fragment_prefix / fn
                if os.path.exists(fn):
                    os.unlink(fn)
    print("Duration - Target: %s Actual: %s" % (target_position, position))
    with open(_cache, "w") as fd:
        json.dump(_CACHE, fd)