#!/usr/bin/env python
# -*- coding: utf-8 -*-
 
 
"""
Copyright 2014 Jan-Philip Gehrcke (http://gehrcke.de)
 
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
 
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""
 
"""
Re-populate a minecraft world. That is, set the TerrainPopulated property
to False for all chunks in a world.
 
From http://minecraft.gamepedia.com/Chunk_format:
 
TerrainPopulated: 1 or not present (true/false) indicate whether the terrain
in this chunk was populated with special things. (Ores, special blocks, trees,
dungeons, flowers, waterfalls, etc.) If set to zero then Minecraft will
regenerate these features in the blocks that already exist.
 
Based on the notes in
https://github.com/mcedit/pymclevel/blob/master/mclevel.py
 
and on the repop method used in
https://github.com/mcedit/mcedit/blob/master/editortools/chunk.py
 
Usage:
 
repop.py path/to/world/directory
 
A world directory is a single directory containing at least one
file named level.dat.
"""
 
 
import os
import sys
import time
import logging
 
logging.basicConfig(
    format='%(asctime)s,%(msecs)-6.1f - %(module)s:%(levelname)s: %(message)s',
    datefmt='%H:%M:%S')
log = logging.getLogger()
log.setLevel(logging.INFO)
 
 
install_note = """
$ virtualenv pyvenv
$ source pyvenv/bin/activate
$ pip install cython numpy pyyaml
$ pip install git+git://github.com/mcedit/pymclevel.git
"""
 
 
try:
    from pymclevel import mclevel
except ImportError:
    sys.exit("Cannot import pymclevel. Consider setting it up via %s" %
        install_note)
 
usage = "%s path/to/world/directory" % os.path.basename(sys.argv[0])
if not len(sys.argv) == 2:
    sys.exit("One argument is required. Usage: %s" % usage)
 
world_directory = sys.argv[1]
 
if not os.path.isdir(world_directory):
    sys.exit("Not a directory: %s" % world_directory)
 
log.info(("Attempting to read world. This scans the directory "
    "for chunks. Might take a while."))
world = mclevel.fromFile(world_directory)
 
log.info("Get chunk positions iterator.")
chunk_positions = world.allChunks
 
log.info("Iterate through chunks, set TerrainPopulated=0 for all of them.")
t0 = time.time()
for idx, (x, z) in enumerate(chunk_positions):
    if (idx + 1) % 1000 == 0:
        log.info("Processed %s chunks." % (idx + 1))
    # Retrieve an AnvilChunk object. This object will load and
    # decompress the chunk as needed, and remember whether it
    # needs to be saved or relighted.
    chunk = world.getChunk(x, z)
    chunk.TerrainPopulated = False
    # The above sets `chunk.dirty` which is processed during
    # `saveInPlace()` below. Leads to `saveChunk(cx, cz, data)`.
duration = time.time() - t0
chunks_per_sec = (idx + 1) / duration
log.info("Total number of modified chunks: %s." % (idx+1))
log.info("Duration: %.2f s. Chunks per second: %.2f." % (
    duration, chunks_per_sec))
 
# Save the level.dat and any chunks that have been marked for
# writing to disk. This also compresses any chunks marked for
# recompression.
log.info("Save modified world to disk (might take a moment).")
world.saveInPlace()
log.info("Exiting.")