# -*- python -*-

# This example uses a text based configuration file to make
# it easier for non-programmers to use Blueshift. It is however
# rather limited, the lisp-esque example is a bit more complex
# but do much more. It will # read a file with the same pathname
# just with ‘.conf’ # appended (‘textconf.conf’ in this case.)
# However, if the filename of this file ends with with ‘rc’,
# that part will be removed, for example, if you rename this
# script to ‘~/.blueshiftrc’ it will read ‘~/.blueshift.conf’
# rather than ‘~/.blueshiftrc.conf’.


# Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
# 
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import os
import sys
import time
import subprocess


# Get the name of .conf file
conf = '%s.conf' % (config_file[:-2] if config_file.endswith('rc') else config_file)


# Read .conf file
with open(conf, 'r') as file:
    conf = file.read()


# Parse .conf file
sections = {'blueshift' : []}
section = []
sections['blueshift'].append(section)
def remove_comment(text, spawn_aware):
    if (';' in text) or ('#' in text):
        if not spawn_aware:
            return text[:text.replace('#', ';').find(';')]
        buf, cmd, stack = '', 0, 0
        for c in text:
            if cmd > 0:
                if c == '(':
                    stack += 1
                elif c == ')':
                    stack -= 1
                if cmd == 1:
                    cmd = 2 if c == '(' else 0
                elif (c == ')') and (stack == 0):
                    cmd = 0
            elif c == '$':
                cmd = 1
                stack = 0
            elif (c == ';') or (c == '#'):
                break
            buf += c
        return buf
    return text
for line in conf.split('\n'):
    line = line.strip()
    if line.startswith('[') and remove_comment(line, False).rstrip().endswith(']'):
        line = remove_comment(line, False).rstrip()
        section_name = line[1 : -1].strip().lower()
        if section_name not in sections:
            sections[section_name] = []
        section = []
        sections[section_name].append(section)
    elif line.startswith(';') or line.startswith('#'):
        continue
    elif ('=' in line) or (':' in line):
        line = remove_comment(line, True)
        if ('=' in line) or (':' in line):
            eq = len(line) if '=' not in line else line.find('=')
            cl = len(line) if ':' not in line else line.find(':')
            eq = min(eq, cl)
            section.append((line[:eq].strip().lower(), line[eq + 1:].strip()))
        elif len(line.strip()) > 0:
            sys.stderr.buffer.write(('Malformated line: %s\n' % line).encode('utf-8'))
    elif len(line.strip()) > 0:
        sys.stderr.buffer.write(('Malformated line: %s\n' % line).encode('utf-8'))
sys.stderr.buffer.flush()


# Default values
location = None
adjustment_method_x = ['randr']
adjustment_method_tty = ['drm']
points = ['solar', '3', '-6']


# List of adjustments and temporary monitor information
adjustments = []
monitors = []
crtc = None
screen = None
name = None
edid = None
bldev = []
blmin = []


def parse_value(value):
    '''
    Parse a setting value
    
    @param   value:str                       The value to parse
    @return  :(list<str>, bool, bool, bool)  The words in the value string, with commands spawned,
                                             and with 'linear', 'cie' and 'default' filtered out,
                                             and their
                                             existance is put as booleans
    '''
    def spawn(cmd):
        '''
        Spawn an external process and read its output, but only the first line
        
        @param   cmd:str  The command to spawn
        @return  :str?    The first line of the command's output, `None` on failure
        '''
        proc = subprocess.Popen(['sh', '-c', cmd], stdout = subprocess.PIPE, stderr = sys.stderr)
        output = proc.communicate()[0].split('\n')[0]
        if (proc.returncode == 0) and (len(output) > 0):
            return output
        return None
    words, buf, cmd, stack = [], '', None, 0
    for c in value:
        if cmd is not None:
            if c == '(':
                stack += 1
            elif c == ')':
                stack -= 1
            if cmd == '':
                if c == '(':
                    cmd += '('
                else:
                    cmd = None
                    buf += '$'
            else:
                cmd += c
                if (c == ')') and (stack == 0):
                    cmd = cmd[1 : -1]
                    cmd = spawn(cmd)
                    if cmd is not None:
                        buf = cmd
                    cmd = None
        elif c == ' ':
            if not buf == '':
                words.append(buf)
                buf = ''
        elif c == '$':
            cmd = ''
            stack = 0
        else:
            buf += c
    if not buf == '':
        words.append(buf)
    return ([w for w in words if w not in ['linear', 'cie', 'default']],
            'linear' in words, 'cie' in words, 'default' in words)


# Evaluate .conf file
def make_f(f, value, default):
    '''
    Make an adjustment function
    
    @param  f:(*¿V??)→void      The function that makes the adjustment
    @param  value:list<¿V??>    The values for each time point
    @param  default:list<¿V??>  The default value
    '''
    ff = None
    value_ = []
    for val in value:
        value_ += val
    if any(map(lambda v : v is None, value_ + default)):
        def ff(t, a):
            val0 = value[(int(t) + 0) % len(value)]
            val1 = value[(int(t) + 1) % len(value)]
            t %= 1
            val = zip(val0, val1, default)
            def interpol(v0, v1, d):
                if (v0 is None) or (v1 is None) or (d is None):
                    if ( d is None) and a == 0:  return None
                    if (v0 is None) and t == 0:  return None
                    if (v1 is None) and t == 1:  return None
                v0 = v0 * (1 - t) if v0 is not None else 0
                v1 = v1 * t       if v1 is not None else 0
                return v0 + v1
            val = [interpol(v0, v1, d) for v0, v1, d in val]
            f(*val)
    else:
        def ff(t, a):
            val0 = value[(int(t) + 0) % len(value)]
            val1 = value[(int(t) + 1) % len(value)]
            t %= 1
            val = zip(val0, val1, default)
            val = [(v0 * (1 - t) + v1 * t) * a + (1 - a) * d for v0, v1, d in val]
            f(*val)
    return ff

def float3(value):
    '''
    Parse a string representation of a float trio
    
    @param   value:str                  The float trio as a string
    @return  :[float?, float?, float?]  The float trio as a float list
    '''
    value = [None if v == 'none' else float(v) for v in value.split(':')]
    if len(value) < 3:
        value *= 3
    return value[:3]

def float6(value):
    '''
    Parse a string representation of a float pair-trio
    
    @param   value:str    The float pair-trio as a string
    @return  :[float?]*6  The float pair-trio as a float list
    '''
    (part1, part2) = [[float(v) for v in val.split(':')] for val in value.split('..')]
    if len(part1) < 3:  part1 *= 3
    if len(part2) < 3:  part2 *= 3
    part1 = part1[:3]
    part2 = part2[:3]
    value = []
    for p, q in zip(part1, part2):
        value.append(p)
        value.append(q)
    return value

backlight_value = 1
def add_adjustments(adjsections, adjustments):
    '''
    Add adjustions from a section to a list
    
    @param  adjsections:list<list<(str, str)>>     The sections
    @param  adjustments:list<(float, float)→void>  The list to fill with adjustments
    '''
    global location, points, adjustment_method_x, adjustment_method_tty, crtc, screen, bldev, blmin, name, edid
    for section in adjsections:
        for (setting, value) in section:
            (value, linear, cie, default) = parse_value(value)
            new_adjustment = None
            if linear:
                adjustments.append(lambda _t, _a: linearise())
            if   setting == 'location':               location = value
            elif setting == 'points':                 points = value
            elif setting == 'adjustment-method-x':    adjustment_method_x = value
            elif setting == 'adjustment-method-tty':  adjustment_method_tty = value
            elif setting == 'crtc':                   crtc = value
            elif setting == 'screen':                 screen = value
            elif setting == 'card':                   screen = value
            elif setting == 'name':                   name = value
            elif setting == 'edid':                   edid = value
            elif setting == 'backlight-device':       bldev = value
            elif setting == 'backlight-minimum':      blmin = [int(v) for v in value]
            elif setting == 'backlight':
                def f(x):
                    global backlight_value
                    backlight_value *= f
                new_adjustment = make_f(f, [[float(v)] for v in value], [1])
            elif setting == 'temperature':
                f_ = cie_temperature if cie else temperature
                f = lambda x : f_(x, lambda t : divide_by_maximum(cmf_10deg(t)))
                new_adjustment = make_f(f, [[float(v)] for v in value], [6500])
            elif setting == 'contrast':
                f = cie_contrast if cie else rgb_contrast
                new_adjustment = make_f(f, [float3(v) for v in value], 3 * [1])
            elif setting == 'brightness':
                f = cie_brightness if cie else rgb_brightness
                new_adjustment = make_f(f, [float3(v) for v in value], 3 * [1])
            elif setting == 'gamma':
                def f(*levels):
                    clip()
                    gamma(*levels)
                new_adjustment = make_f(f, [float3(v) for v in value], 3 * [1])
            elif setting == 'negative':
                def f(*values):
                    negative(*[not v == 0 for v in values])
                new_adjustment = make_f(f, [float3(v) for v in value], 3 * [0])
            elif setting == 'invert':
                def f(*values):
                    (cie_invert if cie else rgb_invert)(*[not v == 0 for v in values])
                new_adjustment = make_f(f, [float3(v) for v in value], 3 * [0])
            elif setting == 'sigmoid':
                new_adjustment = make_f(sigmoid, [float3(v) for v in value], 3 * [None])
            elif setting == 'limits':
                f = cie_limits if cie else rgb_limits
                new_adjustment = make_f(f, [float6(v) for v in value], 3 * [0, 1])
            elif setting == 'icc':
                def noop():
                    pass
                profiles = [noop if val == 'none' else load_load(val) for val in value]
                new_adjustment = make_icc_interpolation(profiles)
            elif setting == 'monitor':
                add_adjustments(sections[' '.join(['monitor'] + value)], adjustments)
            else:
                sys.stderr.buffer.write(('Setting not recognised: %s\n' % setting).encode('utf-8'))
                sys.stderr.buffer.flush()
            if new_adjustment is not None:
                if default:
                    new_adjustment_ = new_adjustment
                    def f(t, a):
                        new_adjustment_(t, 1)
                    new_adjustment = f
                adjustments.append(new_adjustment)
            if linear:
                adjustments.append(lambda _t, _a: standardise())

add_adjustments(sections['blueshift'], adjustments)

adjustment_method = adjustment_method_tty if ttymode else adjustment_method_x
adjustment_method = adjustment_method[0]
list_method = 'randr' if adjustment_method == 'vidmode' else adjustment_method
screen_list = None

for section in sections[adjustment_method]:
    output_adjustments = []
    crtc, screen, name, edid, bldev, blmin = None, None, None, None, [], []
    add_adjustments([section], output_adjustments)
    crtc_screen = (crtc is None) or (screen is None)
    name_edid = (name is not None) or (edid is not None)
    if (screen_list is None) and (crtc_screen or name_edid):
        screen_list = list_screens(list_method)
    if screen is None:
        screen = list(range(len(screen_list)))
    else:
        screen = [int(s) for s in screen]
    crtcs = {}
    for s in screen:
        crtcs[s] = []
        if crtc is not None:
            crtcs[s] += [int(c) for c in crtc]
        elif (name is None) and (edid is None):
            crtcs[s] += list(range(screen_list[s].crtc_count))
        if name is not None:
            s = crtcs[s]
            crtcs[s] += [(d.crtc for d in screen_list.find_by_name(n) if d.crtc not in s) for n in name]
        if edid is not None:
            s = crtcs[s]
            crtcs[s] += [(d.crtc for d in screen_list.find_by_edid(e) if d.crtc not in s) for e in edid]
    monitors.append((crtcs, screen, bldev, blmin, output_adjustments))


# Get gamma adjustment/reader functions
get_method = {'randr' : randr_get, 'vidmode' : vidmode_get, 'drm' : drm_get}
set_method = {'randr' : randr,     'vidmode' : vidmode,     'drm' : drm    }
get_method = get_method[adjustment_method]
set_method = set_method[adjustment_method]


# Save gamma ramps
saved = {}
for crtcs, screens, _bldev, _blmin, _adj in monitors:
    for screen in screens:
        if screen not in saved:
            saved[screen] = {}
        saved_ = saved[screen]
        for crtc in crtcs[screen]:
            saved_[crtc] = get_method(crtc, screen)


# Evaluate location
latitude, longitude = None, None
if 'solar' in points:
    if (location is None) or (len(location) == 0):
        sys.stderr.buffer.write(('Location missing\n').encode('utf-8'))
        sys.stderr.buffer.flush()
        sys.exit(1)
    try:
        if not len(location) == 2:
            raise Exception()
        location = [float(c) for c in location]
    except:
        sys.stderr.buffer.write(('Malformation location\n').encode('utf-8'))
        sys.stderr.buffer.flush()
        sys.exit(1)
    if not ((-90 <= location[0] <= 90) and (-180 <= location[0] <= 180)):
        sys.stderr.buffer.write(('Invalid location\n').encode('utf-8'))
        sys.stderr.buffer.flush()
        sys.exit(1)
    (latitude, longitude) = location


# Evaluate point ## TODO Make this a standard part of Blueshift
if ('solar' not in points) and ('time' not in points):
    sys.stderr.buffer.write(('Invalid points settings\n').encode('utf-8'))
    sys.stderr.buffer.flush()
    sys.exit(1)
reduce_points = 'reduce' in points
solar_points = 'solar' in points
# TODO support brackets (see textconf.conf)
def t(point):
    point = [float(p) for p in point.split(':')]
    while len(point) > 3:
        point.append(0)
    v = sum([v * 60 ** (2 - i) for i, v in enumerate(point)])
    return v % (24 * 60 * 60)
points = [float(p) if solar_points else t(p) for p in points if p not in ['solar', 'time', 'reduce']]
points = list(enumerate(points))
if reduce_points:
    n = len(points) - 1
    points = [(r / n, v) for r, v in points]
get_timepoint = None
points.sort(key = lambda x : x[1])
if not solar_points: # TODO does these really handle `reduce` correctly?
    one_day = 24 * 60 * 60
    points.append((points[0][0], points[0][1] + one_day))
    points = [(points[-2][0], points[-2][1] - one_day)] + points
    def get_timepoint():
        v = time.time() % one_day
        for i in range(len(points) - 1):
            a, b = points[i][1], points[i + 1][1]
            if a <= v <= b:
                a_, b_ = points[i][0], points[i + 1][0]
                v = (v - a) / (b - a)
                if (a_ + 1 == b_) or (b_ == 0):
                    return v + points[i][0]
                else:
                    return points[i][1] - v
        return 1 # should never happen
if solar_points:
    def get_timepoint():
        v = solar_elevation(latitude, longitude)
        for i in range(len(points) - 1):
            a, b = points[i][1], points[i + 1][1]
            if a <= v <= b:
                a_, b_ = points[i][0], points[i + 1][0]
                v = (v - a) / (b - a)
                if (a_ + 1 == b_) or (b_ == 0):
                    return v + points[i][0]
                else:
                    return points[i][1] - v
        if v < points[0][1]:
            return points[0][0]
        return points[-1][0]
    


wait_period = 5
'''
:float  The number of seconds to wait before invoking `periodically` again
'''


# Create backlight device connection
adjbl = False
if 'PATH' in os.environ:
    path = os.environ['PATH'].split(os.path.pathsep)
    sep = os.path.sep
    for p in path:
        f = p + sep + 'adjbacklight'
        if os.path.exists(f):
            if os.access(f, os.X_OK):
                adjbl = True
                break
makebl = lambda dev, blmin : Backlight(dev, adjbacklight = adjbl, minimum = blmin)
makebls = lambda dev, blmin : [makebl(d, b) for d, b in zip(dev, blmin) if not d == 'None']
monitors = [(crtcs, screens, makebls(dev, blmin), adj) for crtcs, screens, dev, blmin, adj in monitors]

# Save backlight settings
saved_backlight_ = [[(b, b.brightness) for b in bl] for _c, _s, bl, _a in monitors if bl is not None]
saved_backlight = []
for sb in saved_backlight_:
    saved_backlight += sb


def periodically(year, month, day, hour, minute, second, weekday, fade):
    '''
    :(int, int, int, int, int, int, int, float?)?→void  Place holder for periodically invoked function
    
    Invoked periodically
    
    If you want to control at what to invoke this function next time
    you can set the value of the global variable `wait_period` to the
    number of seconds to wait before invoking this function again.
    The value does not need to be an integer.
    
    @param   year:int     The year
    @param   month:int    The month, 1 = January, 12 = December
    @param   day:int      The day, minimum value is 1, probable maximum value is 31 (*)
    @param   hour:int     The hour, minimum value is 0, maximum value is 23
    @param   minute:int   The minute, minimum value is 0, maximum value is 59
    @param   second:int   The second, minimum value is 0, probable maximum value is 60 (**)
    @param   weekday:int  The weekday, 1 = Monday, 7 = Sunday
    @param   fade:float?  Blueshift can use this function to fade into a state when it start
                          or exits. `fade` can either be negative, zero or positive or `None`,
                          but the magnitude of value cannot exceed 1. When Blueshift starts,
                          this function will be invoked multiple with the time parameters
                          of the time it is invoked and each time `fade` will increase towards
                          1, starting at 0, when the value is 1, the settings should be applied
                          to 100 %. After this this function will be invoked once again with
                          `fade` being `None`. When Blueshift exits the same behaviour is used
                          except, `fade` decrease towards -1 but start slightly below 0, when
                          -1 is reached all settings should be normal. Then Blueshift will NOT
                          invoke this function with `fade` being `None`, instead it will by
                          itself revert all settings and quit.
    
    (*)  Can be exceeded if the calendar system is changed, like in 1712-(02)Feb-30
    (**) See https://en.wikipedia.org/wiki/Leap_second
    '''
    global backlight_value
    start_over()
    
    alpha = 1 if fade is None else abs(fade)
    timepoint = get_timepoint()
    backlight_value = 1
    
    for adjustment in adjustments:
        adjustment(timepoint, alpha)
    
    stored = store()
    stored_backlight_value = backlight_value
    for crtcs, screens, bldevs, output_adjustments in monitors:
        restore(stored)
        backlight_value = stored_backlight_value
        for adjustment in output_adjustments:
            adjustment(timepoint, alpha)
        
        for screen in screens:
            set_method(*(crtcs[screen]), screen = screen)
        for bldev in bldevs:
            bldev.brightness = backlight_value * bldev.maximum


def reset():
    '''
    Invoked to reset the displays
    '''
    for crtcs, screens, _bldevs, _adj in monitors:
        for screen in screens:
            saved_ = saved[screen]
            for crtc in crtcs[screen]:
                start_over()
                saved_[crtc]()
                set_method(crtc, screen = screen)
    for dev, lvl in saved_backlight:
        dev.brightness = lvl