#!/usr/bin/env python2

"""
namegen.py
==========

---------------------
random name generator
---------------------

:Authors: Elena ``of Valhalla'' Grandi, Diego Roversi
:Date: 2011-09-06
:Copyright: 2011 Elena Grandi, Diego Roversi
:Version: 0.20110906
:Manual Section: 1

SYNOPSIS
--------

   namegen.py (-s <stat_file>)|(-l <list_file>) [-S <dest_file>] [-n <n>]

DESCRIPTION
-----------

OPTIONS
-------

-s <stat_file>, --stats=<stat_file>
   Load rules from <stat_file>.
-l <list_file>, --list=<list_file>
   Generate rules from the files in <list_file>.
-S <dest_file>, --save_stats=<dest_file>
   Save stats in <dest_file>.
-n <n>, --number=<n>
   Generate <n> names (0 to generate no name).
-c <n>, --context=<n>
   Use <n> characters of context in the stats.
-h, --help
   Show an help message.

LICENSE
-------

"""

import sys
import random

try:
    import yaml
    skip_yaml = False
except ImportError:
    sys.stderr.write("Could not find module YAML: will not be able to save / load statistics\n")
    skip_yaml = True

class Stats:

    def __init__(self,context):
        """"""
        self.stats = {}
        self.context = context

    def _increment_stats(self,cont,key):
        if cont in self.stats:
            if key in self.stats[cont]:
                self.stats[cont][key] += 1
            else:
                self.stats[cont][key] = 1
        else:
            self.stats[cont] = {key: 1}

    def read_names(self,fp):
        """Calculate stats from a list of names in a file-like object."""

        for name in fp.readlines():
            for i in xrange(min(self.context,len(name))):
                self._increment_stats(name[0:i],name[i])
            for i in xrange(self.context,len(name)):
                self._increment_stats(name[i-self.context:i],name[i])

    def load_stats(self,fp):
        """Load stats from a yaml in a string or file-like object"""
        if skip_yaml:
            return False
        self.stats = yaml.safe_load(fp)

    def save_stats(self,fp):
        """Save stats in yaml to a file-like object"""
        if skip_yaml:
            return False
        yaml.safe_dump(self.stats,fp)
        return True


    def generate_name(self):
        """Generate a name following the stats"""
        name = ''
        c = ''
        while c != '\n':
            if len(name) <= self.context:
                cont = name
            else:
                cont = name[-self.context:]
            
            chars = ''.join([k*self.stats[cont][k] for k in self.stats[cont]])
            c = random.choice(chars)
            name += c

        return name

def main():
    mystats = Stats(3)
    fp = open('data/nomif2.txt')
    mystats.read_names(fp)
    fp.close()
    print mystats.generate_name(),

if __name__ == '__main__': main()