#
#   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 formatted in HTML or plaintext. Writing to disk and/or
#   emailng data is left to __main__.py.
#

import os
import re
import locale
from string import Template
from math import floor, ceil
from tabulate import tabulate

import logparse
from logparse import interface, util, mail, 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 = ['│', '─']
JXNCHARS_DOUBLE = ['╠', '╣', '╦', '╩', '╬']
JXNCHARS_SINGLE = ['├', '┤', '┬', '┴', '┼']
BULLET = "• "
INDENT = "  "

global VARSUBST

def init_var():
    global VARSUBST
    css_path = config.prefs.get("html", "css")
    if config.prefs.getboolean("html", "css-relpath"):
        if interface.argparser.parse_args().no_write:
            css_path = os.path.relpath(css_path, ".")
        elif interface.argparser.parse_args().destination:
            css_path = os.path.relpath(css_path, interface.argparser.parse_args().destination())
        elif config.prefs.get("logparse", "output"):
            css_path = os.path.relpath(css_path, config.prefs.get("logparse", "output"))
    VARSUBST = {
        "title": config.prefs.get("logparse", "title"),
        "date": interface.start.strftime(DATEFMT),
        "time": interface.start.strftime(TIMEFMT),
        "hostname": util.hostname(config.prefs.get("logparse", "hostname-path")),
        "version": logparse.__version__,
        "css": css_path
    }


class Output:
    """
    Base class for a data processor. 
    """
    
    def __init__(self):
        self.content = ""
        self.destination = ""

    def append(self, content):
        """
        Add a string
        """
        self.content += content

    def write(self, destination=""):
        """
        Output contents into a file
        """
        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))

    def print_stdout(self, lines=False):
        """
        Echo the contents to the console
        """
        print()
        if lines:
            line = PlaintextLine(linewidth=config.prefs.getint("plain", "linewidth"), double=True)
            print(line.draw())
        print(self.content)
        if lines:
            print(line.draw())
        print()



class PlaintextOutput(Output):
    """
    Processes & outputs data in a plaintext form which can be read with cat or plaintext email.
    """

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

    def append_header(self, template=''):
        """
        Print details with some primitive formatting
        """
        box = PlaintextBox(content=Template("$title $version on $hostname\n\n$time $date").safe_substitute(VARSUBST), vpadding=2, hpadding="\t\t", linewidth=self.linewidth)
        line = PlaintextLine(self.linewidth)
        self.append(box.draw() + line.draw())

    def append_footer(self):
        """
        Append a horizontal line and some details
        """
        self.append(PlaintextLine(self.linewidth, vpadding=1).draw())
        self.append(Template("$hostname $time $date").safe_substitute(VARSUBST))

    def append_section(self, section):
        """
        Call the appropriate methods to format a section (provided by a parser).
        This should be run by interface.py after every instance of parse_log().
        """
        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')
        for table in section.tables:
            self.append(table.draw_plain())
        self.append("\n")

    def _fmt_data(self, subtitle, data = None):   # write title and data
        """
        Format the properties of a data object into usable plaintext form with a few fancy symbols/formatting tricks.
        Subtitle is required, data is not. If only subtitle is supplied or subtitle + one data item, a single line will be printed.
        """
        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 = BULLET + datum
                    if len(datum) > self.linewidth - 3:
                        words = datum.split()
                        if max(map(len, words)) > self.linewidth - len(INDENT):
                            continue
                        res, part, others = [], words[0], words[1:]
                        for word in others:
                            if 1 + len(word) > self.linewidth - len(part):
                                res.append(part)
                                part = word
                            else:
                                part += ' ' + word
                        if part:
                            res.append(part)
                        datum = ('\n    ').join(res)
                    datum = INDENT + datum
                    itemoutput += datum + '\n'
                return itemoutput

class HtmlOutput(Output):
    """
    Process and output data in HTML format.
    All HTML formatting functions now reside in this class to differentiate them from plaintext.
    """

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

    def embed_css(self, css):
        """
        Convert stylesheet to inline tags
        """
        if not self._embedded:
            self._embedded = mail.mailprep(self.content, css)
        return self._embedded

    def append_header(self, template):
        """
        Insert variables into header template file and append HTML tags
        """
        headercontent = Template(open(template, 'r').read())
        self.append(headercontent.safe_substitute(VARSUBST))
        self.append(opentag('div', id='main'))

    def append_footer(self):
        """
        Close HTML tags that were opened in the template.
        TODO: add footer template similar to header template.
        """
        self.append(closetag('div') + closetag('body') + closetag('html'))

    def append_section(self, section):
        """
        Call the appropriate methods to generate HTML tags for a section (provided by a parser).
        This should be run by interface.py after every instance of parse_log().
        """
        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))
        for table in section.tables:
            self.append(table.draw_html())
        self.append(closetag('div', 1))

    def _gen_title(self, title):
        """
        Format the 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', False, title)

    def _fmt_data(self, subtitle, data = None):
        """
        Format the properties of a data object into usable HTML tags.
        Subtitle is required, data is not. If only subtitle is supplied or subtitle + one data item, a single line will be printed.
        """
        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', False, subtitle)
        else:
            logger.debug("Received data " + str(data))
            subtitle += ':'
            if (len(data) == 1):
                return tag('p', False, subtitle + ' ' + data[0])
            else:
                output = ""
                output += tag('p', False, 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', False, datum)
                output += closetag('ul', True)
                return output


class Section:
    """
    Each parser should output a Section() which contains the title and returned data.
    """

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

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

    def append_table(self, table):
        self.tables.append(table)


class Data:
    """
    Each section (parser) can have one or more Data() objects which are essentially glorified lists.
    """
    
    def __init__(self, subtitle="", items=[]):
        self.subtitle = subtitle
        self.items = items 

    def truncl(self, limit):      # truncate list
        """
        Truncate self.items to a specified value and state how many items are hidden.
        """
        if (len(self.items) > limit):
            more = len(self.items) - limit
            if more == 1:
                return 0
            self.items = self.items[:limit]
            self.items.append("+ {0} more".format(str(more)))

    def orderbyfreq(self):
        """
        Order a list by frequency of each item, then remove duplicates and append frequency in parentheses.
        """
        unsorted = list(self.items)
        self.items = ["{0} ({1})".format(y, unsorted.count(y)) for y in sorted(set(unsorted), key = lambda x: -unsorted.count(x))]

class Table(object):
    """
    A wrapper for python-tabulate's Tabulate type.
    """
    
    def __init__(self, double=False, borders=False, hpadding=" ", maxwidth=80, headers=[]):
        self.rows =  []     # List of row objects
        self.keymap = {}    # For fast lookup of row by value of first column 
        self.double = double
        self.borders = borders
        self.align_cols = []
        self.hpadding = hpadding
        self.maxwidth = maxwidth
        self.headers = headers
        self._align_cols = []

    def add_row(self, row):

        self.rows.append(row)
        if len(row.columns) > 0:
            self.keymap[row.columns[0]] = row

        logger.debug("Added row with {0} columns".format(str(len(row.columns))))

    def align_column(self, i, align):
        while len(self._align_cols) -1 < i:
            self._align_cols.append("")
        self._align_cols[i] = align
        for row in self.rows:
            row.columns[i].align = align
        logger.debug("Column alignment is now {0}".format(str(self._align_cols)))

    def _gen_list(self):
        hierarchy = []
        for row in self.rows:
            row_data = []
            for column in row.columns:
                row_data.append(column.content)
            hierarchy.append(row_data)
        return hierarchy

    def draw_html(self):
        output = tabulate(self._gen_list(), self.headers, tablefmt="html", colalign=tuple(self._align_cols))
        return output

    def draw_plain(self):
        output = tabulate(self._gen_list(), self.headers, tablefmt="fancy_grid" if self.borders else "plain", colalign=tuple(self._align_cols))
        return output + "\n"*2


class Table0(object):
    """
    A two-dimensional information display.
    This is a hacky implementation - Table() now relies on the Tabulate package which is much more reliable.
    """

    def __init__(self, double=False, borders=True, hpadding="+", maxwidth=80):
        self.rows =  []     # List of row objects
        self.keymap = {}    # For fast lookup of row by value of first column 
        self.double = double
        self.borders = borders
        self.align_cols = []
        self.hpadding = hpadding
        self.maxwidth = maxwidth
        self._colwidths = []

    def add_row(self, row):
        self.rows.append(row)
        for i, col in enumerate(row.columns):
            if len(self._colwidths) >= i + 1:
                self._colwidths[i] = max([self._colwidths[i], len(col.content)])
            else:
                self._colwidths.append(len(col.content))
        logger.debug("Added row with {0} columns. Column widths are now {1}.".format(str(len(row.columns)), str(self._colwidths)))
        if len(row.columns) > 0:
            self.keymap[row.columns[0]] = row
    
    def align_column(self, i, align):
        for row in self.rows:
            row.columns[i].align = align
        

    def draw_html(self):
        output = ""
        output += opentag("table", True, cl="data_table") 
        for row in self.rows:
            if row.header:
                output += opentag("th", block=True, cl="header")
            else:
                output += opentag("tr", block=True)
            for column in row.columns:
                output += tag("td", content=column.content, style={"text-align": column.align} if column.align else {})
            if row.header:
                output += closetag("th", True)
            else:
                output += closetag("tr", True)
        output += closetag("table", True)
        logger.debug("Built table with {0} rows and {1} columns".format(str(len(self.rows)), str(max([x.n for x in self.rows]))))
        return output

    def draw_plain(self):
        output = ""
        cols = [list(x) for x in zip(self.rows)]
        logger.debug("Cols are " + str(cols))

        if self.double == True:
            cornerchars = CORNERCHARS_DOUBLE
            linechars = LINECHARS_DOUBLE
            jxnchars = JXNCHARS_DOUBLE
        else:
            cornerchars = CORNERCHARS_SINGLE
            linechars = LINECHARS_SINGLE
            jxnchars = JXNCHARS_SINGLE
        
        lengths = []
        row_lengths = []
        for row in self.rows:
            for i, col in enumerate(row.columns):
                if len(lengths) >= i + 1:
                    lengths[i] = max([lengths[i], len(col.content)])
                else:
                    lengths.append(len(col.content))

        logger.debug("Lengths are " + str(lengths))

        for i, row in enumerate(self.rows):
            l = (len(INDENT) + len(self.hpadding)*2*len(row.columns) + ((1+len(row.columns)) if self.borders else 0) + sum([len(col.content) for col in row.columns]))
            if l > self.maxwidth:
                logger.debug("Line overflow for cell in row {0} of table".format(str(i)))
                words = row.columns[-1].content.split()
                if max(map(len, words)) > self.maxwidth:
                    continue
                res, part, others = [], words[0], words[1:]
                for word in others:
                    if l - len(word) < self.maxwidth:
                        res.append(part)
                        part = word
                    else:
                        part += ' ' + word
                if part:
                    res.append(part)
                self._colwidths[-1] = max([len(f) for f in res] + [len(r.columns[-1].content) for r in self.rows if r != row])
                if self.borders:
                    row.columns[-1].content = res[0][:-1] + self.hpadding + " "*(self._colwidths[-1]-len(res[0])+1) + linechars[0]
                    for fragment in res[1:]:
                        row.columns[-1].content += "\n" + INDENT + "".join([(linechars[0] + self.hpadding + " "*x + self.hpadding) for x in lengths]) + linechars[0] + self.hpadding + fragment + " " * (max(self._colwidths) - len(fragment))

        if self.borders:
            top = INDENT + cornerchars[3] + jxnchars[2].join(linechars[1] * (l+2) for l in self._colwidths) + cornerchars[2] + "\n"
            bottom = INDENT + cornerchars[0] + jxnchars[3].join(linechars[1] * (l+2) for l in self._colwidths) + cornerchars[1] + "\n"
            rowtext = INDENT + linechars[0] + linechars[0].join("{:>%d}" % l for l in self._colwidths) + linechars[0] + "\n"
            line = INDENT + jxnchars[0] + jxnchars[4].join(linechars[1] * (l+2) for l in self._colwidths) + jxnchars[1] + "\n"
        else:
            top = bottom = line = ""
            rowtext = " ".join("{:>%d}" % l for l in self._colwidths) + "\n"

        for i, row in enumerate(self.rows):
            logger.debug("Processing row {0} of {1}".format(str(i), str(len(self.rows)-1)))
            row_output = ""
            if i == 0:
                row_output += top
            row_output += (INDENT + linechars[0] if self.borders else "")
            for j, column in enumerate(row.columns):
                if column.align == "right":
                    cell_output = self.hpadding + " "*(self._colwidths[j]-len(column.content)) + column.content + self.hpadding + (linechars[0] if self.borders else "")
                elif column.align == "left":
                    cell_output = self.hpadding + column.content + " "*(self._colwidths[j]-len(column.content)) + self.hpadding + (linechars[0] if self.borders else "")
                elif column.align == "center":
                    n_whitespace = (self._colwidths[j]-len(column.content))/2
                    cell_output = self.hpadding + " "*(floor(n_whitespace) if len(column.content) % 2 == 0 else ceil(n_whitespace)) + column.content + " "*(ceil(n_whitespace) if len(column.content) % 2 == 0 else floor(n_whitespace)) + self.hpadding + (linechars[0] if self.borders else "")
                else:
                    logger.warning("Couldn't find alignment value for cell {0} of row {1} with content \"{2}\"".format(str(j), str(i), column.content()))
                    continue
                row_output += cell_output
                if len(row_output) > self.maxwidth:
                    logger.warning("Line overflow for row {0} of table".format(str(i)))

            output += row_output + "\n"
            if i == len(self.rows)-1:
                output += (bottom if self.borders else "")
            else:
                output += (line if self.borders else "")

        return output

class Row(object):
    
    def __init__(self, columns=[], header=False):
        self.columns = columns
        self.header = header
        self.n = len(self.columns)

    def add_column(self, column):
        self.columns.append(column)
        self.n += 1

    def rm_column(self, column):
        self.remove(column)
        self.n -= 1

class Column(object):

    def __init__(self, content="", align="right"):
        self.content = content
        self.align = align

class PlaintextLine:
    """
    Draw a horizontal line for plain text format, with optional padding/styling.
    """

    def __init__(self, linewidth=80, double=True, vpadding=1, hpadding=""):
        self.linewidth = linewidth
        self.double = double
        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:
    """
    Draw a rectangular box around text, with customisable padding/size/style
    """

    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:
                    continue
                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 backticks(l):
    return ["`" + x + "`" for x in l]


def plural(noun, quantity, print_quantity=True):
    """
    Return "1 noun" or "n nouns"
    """
    if print_quantity:
        if (quantity == 1):
            return(str(quantity) + " " + noun)
        else:
            return(str(quantity) + " " + noun + "s")
    else:
        if (quantity == 1):
            return noun
        else:
            return 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(subject):
    """
    Replace variables in the title template provided in config
    """
    r = Template(subject).safe_substitute(VARSUBST)
    logger.debug("Returning subject line " + r)
    return r

def opentag(tag, block=False, id=None, cl=None, style=None):
    """
    Write HTML opening tag
    """
    output = ""
    if block:
        output += '\n'
    output += '<' + tag
    if id:
        output += " id='" + id + "'"
    if cl:
        output += " class='" + cl + "'"
    if style:
        output += " style='"
        output += " ".join("{0}: {1};".format(attr, value) for attr, value in style.items())
        output += "'"
    output += '>'
    if block:
        output += '\n'
    return output

def closetag(tag, block=False):
    """
    Write HTML closing tag
    """
    if block:
        return "\n</" + tag + ">\n"
    else:
        return "</" + tag + ">"

def tag(tag, block=False, content="", id=None, cl=None, style=None):
    """
    Write HTML opening tag, content, and closing tag
    """
    o = opentag(tag, block, id, cl, style)
    c = closetag(tag, block)
    return o + content + c