# cachethg.py - overlay/status cache
#
# Copyright 2008 Steve Borho <steve@borho.org>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.

import os
import sys

from mercurial import hg, util, ui, node, merge, error, scmutil
from tortoisehg.util import paths, debugthg, hglib

debugging = False
enabled = True
localonly = False
includepaths = []
excludepaths = []

try:
    from _winreg import HKEY_CURRENT_USER, OpenKey, QueryValueEx
    from win32api import GetTickCount
    CACHE_TIMEOUT = 5000
    try:
        hkey = OpenKey(HKEY_CURRENT_USER, r"Software\TortoiseHg")
        enabled = QueryValueEx(hkey, 'EnableOverlays')[0] in ('1', 'True')
        localonly = QueryValueEx(hkey, 'LocalDisksOnly')[0] in ('1', 'True')
        incs = QueryValueEx(hkey, 'IncludePath')[0]
        excs = QueryValueEx(hkey, 'ExcludePath')[0]
        debugging = QueryValueEx(hkey, 'OverlayDebug')[0] in ('1', 'True')
        for p in incs.split(';'):
            path = p.strip()
            if path:
                includepaths.append(path)
        for p in excs.split(';'):
            path = p.strip()
            if path:
                excludepaths.append(path)
    except EnvironmentError:
        pass
except ImportError:
    from time import time as GetTickCount
    CACHE_TIMEOUT = 5.0
    debugging = debugthg.debug('O')

if debugging:
    debugf = debugthg.debugf
    debugf('Enabled %s', enabled)
    debugf('LocalDisksOnly %s', localonly)
    debugf('IncludePaths %s', includepaths)
    debugf('ExcludePaths %s', excludepaths)
else:
    debugf = debugthg.debugf_No

STATUS_STATES = 'MAR!?IC'
MODIFIED, ADDED, REMOVED, DELETED, UNKNOWN, IGNORED, UNCHANGED = STATUS_STATES
NOT_IN_REPO = ' '
ROOT = "r"
UNRESOLVED = 'U'

# file status cache
overlay_cache = {}
cache_tick_count = 0
cache_root = None
cache_pdir = None


def add_dirs(list):
    dirs = set()
    if list:
        dirs.add('')
    for f in list:
        pdir = os.path.dirname(f)
        if pdir in dirs:
            continue
        while pdir:
            dirs.add(pdir)
            pdir = os.path.dirname(pdir)
    list.extend(dirs)


def get_state(upath, repo=None):
    """
    Get the state of a given path in source control.
    """
    states = get_states(upath, repo)
    return states and states[0] or NOT_IN_REPO


def get_states(upath, repo=None):
    """
    Get the states of a given path in source control.
    """
    global overlay_cache, cache_tick_count
    global cache_root, cache_pdir
    global enabled, localonly
    global includepaths, excludepaths

    #debugf("called: _get_state(%s)", path)
    tc = GetTickCount()

    try:
        # handle some Asian charsets
        path = upath.encode('mbcs')
    except:
        path = upath
     # check if path is cached
    pdir = os.path.dirname(path)
    status = overlay_cache.get(path, '')
    if overlay_cache and (cache_pdir == pdir or cache_pdir and
              status not in ' r' and path.startswith(cache_pdir)):
        #use cached data when pdir has not changed or when the cached state is a repo state
        if tc - cache_tick_count < CACHE_TIMEOUT:
            if not status:
                if os.path.isdir(os.path.join(path, '.hg')):
                    add(path, ROOT)
                    status = ROOT
                else:
                    status = overlay_cache.get(pdir + '*', NOT_IN_REPO)
                    add(path, status)
                debugf("%s: %s (cached~)", (path, status))
            else:
                debugf("%s: %s (cached)", (path, status))
            return status
        else:
            debugf("Timed out!!")
            overlay_cache.clear()
            cache_tick_count = GetTickCount()
     # path is a drive
    if path.endswith(":\\"):
        add(path, NOT_IN_REPO)
        return NOT_IN_REPO
     # open repo
    if cache_pdir == pdir:
        root = cache_root
    else:
        debugf("find new root")
        root = paths.find_root(path)
        if root == path:
            if not overlay_cache:
                cache_root = pdir
            add(path, ROOT)
            debugf("%s: r", path)
            return ROOT
        cache_root = root
        cache_pdir = pdir

    if root is None:
        debugf("_get_state: not in repo")
        overlay_cache = {None: None}
        cache_tick_count = GetTickCount()
        return NOT_IN_REPO
    debugf("_get_state: root = " + root)
    hgdir = os.path.join(root, '.hg', '')
    if pdir == hgdir[:-1] or pdir.startswith(hgdir):
        add(pdir, NOT_IN_REPO)
        return NOT_IN_REPO
    try:
        if not enabled:
            overlay_cache = {None: None}
            cache_tick_count = GetTickCount()
            debugf("overlayicons disabled")
            return NOT_IN_REPO
        if localonly and not paths.is_on_fixed_drive(path):
            debugf("%s: is a network drive", path)
            overlay_cache = {None: None}
            cache_tick_count = GetTickCount()
            return NOT_IN_REPO
        if includepaths:
            for p in includepaths:
                if path.startswith(p):
                    break
            else:
                debugf("%s: is not in an include path", path)
                overlay_cache = {None: None}
                cache_tick_count = GetTickCount()
                return NOT_IN_REPO
        for p in excludepaths:
            if path.startswith(p):
                debugf("%s: is in an exclude path", path)
                overlay_cache = {None: None}
                cache_tick_count = GetTickCount()
                return NOT_IN_REPO
        tc1 = GetTickCount()
        real = os.path.realpath #only test if necessary (symlink in path)
        if not repo or (repo.root != root and repo.root != real(root)):
            repo = hg.repository(ui.ui(), path=root)
            debugf("hg.repository() took %g ticks", (GetTickCount() - tc1))
    except error.RepoError:
        # We aren't in a working tree
        debugf("%s: not in repo", pdir)
        add(pdir + '*', IGNORED)
        return IGNORED
    except Exception, e:
        debugf("error while handling %s:", pdir)
        debugf(e)
        add(pdir + '*', UNKNOWN)
        return UNKNOWN

     # get file status
    tc1 = GetTickCount()

    try:
        matcher = scmutil.match(repo[None], [pdir])
        repostate = repo.status(match=matcher, ignored=True,
                        clean=True, unknown=True)
    except util.Abort, inst:
        debugf("abort: %s", inst)
        debugf("treat as unknown : %s", path)
        return UNKNOWN

    debugf("status() took %g ticks", (GetTickCount() - tc1))
    mergestate = repo.dirstate.parents()[1] != node.nullid and \
              hasattr(merge, 'mergestate')

    # cached file info
    tc = GetTickCount()
    overlay_cache = {}
    add(root, ROOT)
    add(os.path.join(root, '.hg'), NOT_IN_REPO)
    states = STATUS_STATES
    if mergestate:
        mstate = merge.mergestate(repo)
        unresolved = [f for f in mstate if mstate[f] == 'u']
        if unresolved:
            modified = repostate[0]
            modified[:] = set(modified) - set(unresolved)
            repostate.insert(0, unresolved)
            states = [UNRESOLVED] + states
    states = zip(repostate, states)
    states[-1], states[-2] = states[-2], states[-1] #clean before ignored
    for grp, st in states:
        add_dirs(grp)
        for f in grp:
            fpath = os.path.join(root, os.path.normpath(f))
            add(fpath, st)
    status = overlay_cache.get(path, UNKNOWN)
    debugf("%s: %s", (path, status))
    cache_tick_count = GetTickCount()
    return status


def add(path, state):
    overlay_cache[path] = overlay_cache.get(path, '') + state
