#
#   format.py
#   
#   This file contains global functions for formatting and printing data. This
#   file should be imported into individual log-parsing scripts located in
#   logs/*. Data is all formatted in HTML. Writing to disk and/or emailng data
#   is left to __main__.py.
#

import os
import re
import locale
from string import Template

import logparse
from . import interface, util, config

import logging
logger = logging.getLogger(__name__)

locale.setlocale(locale.LC_ALL, '') # inherit system locale
#DEG = "°".encode('unicode_escape')
DEG = u'\N{DEGREE SIGN}'
CEL = "C"
TIMEFMT = "%X"
DATEFMT = "%x"
CORNERCHARS_DOUBLE = ['╚', '╝', '╗', '╔']
CORNERCHARS_SINGLE = ['└', '┘', '┐', '┌']
LINECHARS_DOUBLE = ['║', '═']
LINECHARS_SINGLE = ['│', '─']

class Output:
    
    def __init__(self):
        self.content = ""
        self.destination = ""

    def append(self, content):
        self.content += content

    def write(self, destination=""):
        if destination == "":
            destination = self.destination
        if destination == "":
            logger.warning("No destination path provided")
            return 1
        with open(destination, 'w') as f:
            f.write(self.content)
            logger.info("Written output to {}".format(destination))


class PlaintextOutput(Output):

    def __init__(self, linewidth=80):
        self.content = ""
        self.destination = ""
        self.linewidth = linewidth;

    def append_header(self, template=''):
        init_varfilter()
        box = PlaintextBox(content=Template("$title $version on $hostname\n\n$time $date").safe_substitute(varsubst), vpadding=2, hpadding="\t\t", linewidth=config.prefs['linewidth'])
        line = PlaintextLine(self.linewidth)
        self.append(box.draw() + line.draw())

    def append_footer(self):
        init_varfilter()
        self.append(PlaintextLine(self.linewidth, vpadding=1).draw())
        self.append(Template("$hostname $time $date").safe_substitute(varsubst))

    def append_section(self, section):
        self.append(PlaintextBox(content=section.title, double=False, fullwidth=False, vpadding=0, hpadding=" ").draw())
        self.append('\n'*2)
        for data in section.data:
            self.append(self._fmt_data(data.subtitle, data.items))
        self.append('\n')

    def _fmt_data(self, subtitle, data = None):   # write title and data
        if (subtitle == ""):
            logger.warning("No subtitle provided.. skipping section")
            return

        if (data == None or len(data) == 0):
            logger.debug("No data provided.. just printing subtitle")
            return subtitle + '\n'
        else:
            logger.debug("Received data " + str(data))
            subtitle += ':'
            if (len(data) == 1):
                return subtitle + ' ' + data[0] + '\n'
            else:
                itemoutput = subtitle + '\n'
                for datum in data:
                    datum = '• ' + datum
                    if len(datum) > config.prefs['linewidth']:
                        words = datum.split()
                        if max(map(len, words)) > config.prefs['linewidth']:
                            raise ValueError("Content width is too small")
                        res, part, others = [], words[0], words[1:]
                        for word in others:
                            if len(' ') + len(word) > config.prefs['linewidth'] - len(part):
                                res.append(part)
                                part = word
                            else:
                                part += ' ' + word
                        if part:
                            res.append(part)
                        datum = '\n'.join(res)
                    itemoutput += datum + '\n'
                return itemoutput


class HtmlOutput(Output):

    def __init__(self):
        self.content = ""
        self.destination = ""
        self.css = ""

    def embed_css(self, css):
        self.content = mail.mailprep(self.content, css)

    def append_header(self, template):   # insert variables into header template file
        init_varfilter()
        headercontent = Template(open(template, 'r').read())
        self.append(headercontent.safe_substitute(varsubst))
        self.append(opentag('div', id='main'))

    def append_footer(self):
        self.append(closetag('div') + closetag('body') + closetag('html'))

    def append_section(self, section):
        self.append(opentag('div', 1, section.title, 'section'))
        self.append(self._gen_title(section.title))
        for data in section.data:
            self.append(self._fmt_data(data.subtitle, data.items))
        self.append(closetag('div', 1))

    def _gen_title(self, title):  # write title for a section
        if (title == '' or '\n' in title):
            logger.error("Invalid title")
            raise ValueError 
        logger.debug("Writing title for " + title)
        return tag('h2', 0, title)

    def _fmt_data(self, subtitle, data = None):   # write title and data
        if (subtitle == ""):
            logger.warning("No subtitle provided.. skipping section")
            return

        if (data == None or len(data) == 0):
            logger.debug("No data provided.. just printing subtitle")
            return tag('p', 0, subtitle)
        else:
            logger.debug("Received data " + str(data))
            subtitle += ':'
            if (len(data) == 1):
                return tag('p', 0, subtitle + ' ' + data[0])
            else:
                output = ""
                output += tag('p', 0, subtitle)
                output += opentag('ul', 1)
                coderegex = re.compile('`(.*)`')
                for datum in data:
                    if datum == "" or datum == None:
                        continue
                    datum = coderegex.sub(r'<code>{\1}</code>', str(datum))
                    output += tag('li', 0, datum)
                output += closetag('ul', 1)
                return output


class Section:

    def __init__(self, title):
        self.title = title
        self.data = []

    def add_data(self, data):
        self.data.append(data)

class Data:
    
    def __init__(self, subtitle, items=None):
        self.subtitle = subtitle
        self.items = items 


class PlaintextLine:

    def __init__(self, linewidth=80, double=True, vpadding=1, hpadding=""):
        self.linewidth = linewidth
        self.double = False
        self.vpadding = vpadding
        self.hpadding = hpadding

    def draw(self):
        line = (LINECHARS_DOUBLE[1] if self.double else LINECHARS_SINGLE[1])
        return "\n" * self.vpadding + self.hpadding +  line * (self.linewidth - 2 * len(self.hpadding)) + self.hpadding + "\n" * self.vpadding

class PlaintextBox:

    def __init__(self, content="", double=True, fullwidth=True, linewidth=80, hpadding="\t", vpadding=1):
        self.content = content
        self.fullwidth = fullwidth
        self.linewidth = linewidth
        self.hpadding = hpadding 
        self.vpadding = vpadding
        self.double = double

    def draw(self):

        if self.double == True:
            cornerchars = CORNERCHARS_DOUBLE
            linechars = LINECHARS_DOUBLE
        else:
            cornerchars = CORNERCHARS_SINGLE
            linechars = LINECHARS_SINGLE

        # Check hpadding has a definite width
        self.hpadding = self.hpadding.replace("\t", " "*4)

        # Calculate number of characters per line
        contentlines = self.content.splitlines()
        contentwidth = int((self.linewidth if self.linewidth > 0 else 80) if self.content.splitlines() else len(max(contentlines, key=len)))
        logger.debug("Contentwidth is {0}".format(str(contentwidth)))
        logger.debug("Longest line is {0}".format(len(max(contentlines, key=len))))
        contentwidth += -2*(len(self.hpadding)+1)
        if not self.fullwidth:
            longestline = len(max(contentlines, key=len))
            if longestline <= self.linewidth - 2*(len(self.hpadding)+1):
                contentwidth = longestline

        # Split lines that are too long
        for i, line in enumerate(contentlines):
            if len(line) > contentwidth:
                words = line.split()
                if max(map(len, words)) > contentwidth:
                    raise ValueError("Content width is too small")
                res, part, others = [], words[0], words[1:]
                for word in others:
                    if len(' ') + len(word) > contentwidth - len(part):
                        res.append(part)
                        part = word
                    else:
                        part += ' ' + word
                if part:
                    res.append(part)
                contentlines[i] = res

        # Flatten list
        #   Note list comprehension doesn't work here, so we must iterate through each item
        newlines = []
        for line in contentlines:
            if isinstance(line, list):
                for subline in line:
                    newlines.append(subline)
            else:
                newlines.append(line)
        contentlines = newlines
               
        # Add vertical padding
        for _ in range(self.vpadding):
            contentlines.insert(0, ' '*contentwidth)
            contentlines.append(' '*contentwidth)

        # Insert horizontal padding on lines that are too short
        contentlines = [linechars[0] + self.hpadding + x + ' '*(self.linewidth-(len(x)+2*len(self.hpadding)+2) if len(x) < contentwidth else 0) + self.hpadding + linechars[0] for x in contentlines]
        contentlines.insert(0, cornerchars[3] + linechars[1] * (contentwidth + len(self.hpadding)*2) + cornerchars[2])
        contentlines.append(cornerchars[0] + linechars[1] * (contentwidth + len(self.hpadding)*2) + cornerchars[1])
        return ('\n').join(contentlines)

def init_varfilter():
    global varfilter
    global varpattern
    global varsubst
    varfilter = {"$title$": config.prefs['title'], "$date$": interface.start.strftime(DATEFMT),"$time$": interface.start.strftime(TIMEFMT), "$hostname$": util.hostname(config.prefs['hostname-path']), "$version$": logparse.__version__, "$css$": os.path.relpath(config.prefs['css'], os.path.dirname(config.prefs['output']))}
    varfilter = dict((re.escape(k), v) for k, v in varfilter.items())
    varpattern = re.compile("|".join(varfilter.keys()))
    varsubst = dict(title=config.prefs['title'], date=interface.start.strftime(DATEFMT), time=interface.start.strftime(TIMEFMT), hostname=util.hostname(config.prefs['hostname-path']), version=logparse.__version__, css=os.path.relpath(config.prefs['css'], os.path.dirname(config.prefs['output'])))

def writetitle(title):  # write title for a section
    if (title == '' or '\n' in title):
        logger.error("Invalid title")
        raise ValueError 
    logger.debug("Writing title for " + title)
    return tag('h2', 0, title)

def opentag(tag, block = 0, id = None, cl = None):   # write html opening tag
    output = ""
    if (block):
        output += '\n'
    output += '<' + tag
    if (id != None):
        output += " id='" + id + "'"
    if (cl != None):
        output += " class='" + cl + "'"
    output += '>'
    if (block):
        output += '\n'
    return output

def closetag(tag, block = 0):  # write html closing tag
    if (block == 0):
        return "</" + tag + ">"
    else:
        return "\n</" + tag + ">\n"

def tag(tag, block = 0, content = ""):  # write html opening tag, content, and html closing tag
    o = opentag(tag, block)
    c = closetag(tag, block)
    return o + content + c

def orderbyfreq(l):     # order a list by the frequency of its elements and remove duplicates
    temp_l = l[:]
    l = list(set(l))
    l = [[i, temp_l.count(i)] for i in l]   # add count of each element
    l.sort(key=lambda x:temp_l.count(x[0])) # sort by count
    l = [i[0] + ' (' + str(i[1]) + ')' for i in l]  # put element and count into string
    l = l[::-1]     # reverse
    return l

def addtag(l, tag):  # add prefix and suffix tags to each item in a list
    l2 = ['<' + tag + '>' + i + '</' + tag + '>' for i in l]
    return l2

def truncl(input, limit):      # truncate list
    if (len(input) > limit):
        more = str(len(input) - limit)
        output = input[:limit]
        output.append("+ " + more + " more")
        return(output)
    else:
        return(input)

def plural(noun, quantity): # return "1 noun" or "n nouns"
    if (quantity == 1):
        return(str(quantity) + " " + noun)
    else:
        return(str(quantity) + " " + noun + "s")

def parsesize(num, suffix='B'):     # return human-readable size from number of bytes
    for unit in ['','Ki','Mi','Gi','Ti','Pi','Ei','Zi']:
        if abs(num) < 1024.0:
            return "%3.1f %s%s" % (num, unit, suffix)
        num /= 1024.0
    return "%.1f%s%s" % (num, 'Yi', suffix)

def fsubject(template): # Replace variables in the title template provided in config
    r = varpattern.sub(lambda m: varfilter[re.escape(m.group(0))], template)
    logger.debug("Returning subject line " + r)
    return r

def writedata(subtitle, data = None):   # write title and data
    if (subtitle == ""):
        logger.warning("No subtitle provided.. skipping section")
        return

    if (data == None or len(data) == 0):
        logger.debug("No data provided.. just printing subtitle")
        return tag('p', 0, subtitle)
    else:
        logger.debug("Received data " + str(data))
        subtitle += ':'
        if (len(data) == 1):
            return tag('p', 0, subtitle + ' ' + data[0])
        else:
            output = ""
            output += tag('p', 0, subtitle)
            output += opentag('ul', 1)
            for datum in data:
                output += tag('li', 0, datum)
            output += closetag('ul', 1)
            return output