# walker.py                                     -*- coding: ISO-8859-1 -*-
#
#   Copyright © 2000, 2004 Carey Evans.
#
#   Permission to use, copy, modify, and distribute this software and
#   its documentation for any purpose and without fee is hereby granted,
#   provided that the above copyright notice appear in all copies and
#   that both that copyright notice and this permission notice appear in
#   supporting documentation.
#
#   $Id: walker.py 15 2004-01-12 05:15:13Z carey $

"""walker.py

Check all the pages passed from the sitemap, and build where necessary.
"""

import sys, os, errno
import shutil

import builder

loglevel = 1

def log(message, level=0):
    if level <= loglevel:
        sys.stderr.write(message)

class PageWalker:
    def __init__(self, srcdir, dstdir, build_all):
        self.srcdir = srcdir
        self.dstdir = dstdir
        self.all = build_all
        self.builder = builder.PageBuilder()

    def process(self, dirs):
        for d in dirs:
            log('Entering %s\n' % d.srcfile(self.srcdir), 1)
            self.process_pages(d)
            self.process_datafiles(d)

    def process_pages(self, dir):
        for p in dir.pages:
            src = p.srcfile(self.srcdir)
            dst = p.dstfile(self.dstdir)
            if self.checkbuild(p.path[-1], src, dst):
                d = os.path.dirname(dst)
                if not os.path.isdir(d):
                    os.makedirs(d)
                self.builder.build(p, src, dst)

    def process_datafiles(self, dir):
        for d in dir.datafiles:
            src = d.srcfile(self.srcdir)
            dst = d.dstfile(self.dstdir)
            if self.checkbuild(d.path[-1], src, dst):
                shutil.copyfile(src, dst)

    def checkbuild(self, file, src, dst):
        try:
            srctime = os.path.getmtime(src)
        except OSError, e:
            if e.errno == errno.ENOENT:
                log(' ! Source not found, skipping %s\n' % (file,))
                return 0
            else:
                raise

        if self.all:
            log(' + Build all, processing %s\n' % (file,), 1)
            return 1

        try:
            dsttime = os.path.getmtime(dst)
        except OSError, e:
            if e.errno == errno.ENOENT:
                log(' + Dest not found, processing %s\n' % (file,), 1)
                return 1
            raise

        if srctime > dsttime:
            log(' + Source is newer, processing %s\n' % (file,), 1)
            return 1
        else:
            log(' - Dest is newer, skipping %s\n' % (file,), 2)
            return 0