#!/usr/bin/env python3
#
# See docs/subsystems/emoji.md for a high-level explanation of how this system
# works.
import os
import sys
import ujson

from typing import Any, Dict, List

from emoji_setup_utils import generate_emoji_catalog, generate_codepoint_to_name_map, \
    generate_name_to_codepoint_map, emoji_names_for_picker, EMOJISETS
from emoji_names import EMOJI_NAME_MAPS

ZULIP_PATH = os.path.join(os.path.dirname(os.path.abspath(__file__)), '../../../')
sys.path.append(ZULIP_PATH)

from scripts.lib.zulip_tools import generate_sha1sum_emoji, run

TARGET_EMOJI_DUMP = os.path.join(ZULIP_PATH, 'static', 'generated', 'emoji')
EMOJI_CACHE_PATH = "/srv/zulip-emoji-cache"
EMOJI_SCRIPT_DIR_PATH = os.path.join(ZULIP_PATH, 'tools', 'setup', 'emoji')
NODE_MODULES_PATH = os.path.join(ZULIP_PATH, 'node_modules')

EMOJI_CODES_FILE_TEMPLATE = """\
var emoji_codes = (function () {
var exports = {};

exports.names = %(names)s;

exports.name_to_codepoint = %(name_to_codepoint)s;

exports.codepoint_to_name = %(codepoint_to_name)s;

exports.emoji_catalog = %(emoji_catalog)s;

return exports;
}());
if (typeof module !== 'undefined') {
    module.exports = emoji_codes;
}
"""

SPRITE_CSS_FILE_TEMPLATE = """\
div.emoji,
span.emoji
{
    display: inline-block;
    background-image: url('sheet_%(emojiset)s_64.png');
    -webkit-background-size: 4900%%;
    -moz-background-size: 4900%%;
    background-size: 4900%%;
    background-repeat: no-repeat;

    /* Hide the text. */
    text-indent: 100%%;
    white-space: nowrap;
    overflow: hidden;
}

%(emoji_positions)s
"""

EMOJI_POS_INFO_TEMPLATE = """\
.emoji-%(codepoint)s {
    background-position: %(pos_x)s%% %(pos_y)s%%;
}
"""

# change directory
os.chdir(EMOJI_SCRIPT_DIR_PATH)

if 'TRAVIS' in os.environ:
    # In Travis CI, we don't have root access
    EMOJI_CACHE_PATH = "/home/travis/zulip-emoji-cache"

def main() -> None:
    success_stamp = get_success_stamp()
    source_emoji_dump = os.path.dirname(success_stamp)

    if not os.path.exists(success_stamp):
        print("Dumping emojis ...")
        dump_emojis(source_emoji_dump)
        run(['touch', success_stamp])

    print("Using cached emojis from {}".format(source_emoji_dump))
    run(['rm', '-rf', TARGET_EMOJI_DUMP])
    os.symlink(source_emoji_dump, TARGET_EMOJI_DUMP)

def get_success_stamp() -> str:
    sha1_hexdigest = generate_sha1sum_emoji(ZULIP_PATH)
    return os.path.join(EMOJI_CACHE_PATH, sha1_hexdigest, 'emoji', '.success-stamp')

def generate_sprite_css_files(cache_path: str, emoji_data: List[Dict[str, Any]]) -> None:
    # Spritesheet CSS generation code.
    emoji_positions = ""
    for emoji in emoji_data:
        if emoji["has_img_google"]:
            # Why is the test here has_img_google and not
            # emoji_is_universal?  Because we briefly supported all
            # Google emoji (not just the universal ones), we need to
            # ensure the spritesheet is setup to correctly display
            # those google emoji (in case anyone used them).
            emoji_positions += EMOJI_POS_INFO_TEMPLATE % {
                'codepoint': emoji['unified'].lower(),
                'pos_x': (emoji["sheet_x"] * 100) / 48,
                'pos_y': (emoji["sheet_y"] * 100) / 48,
            }

    for emojiset in EMOJISETS:
        SPRITE_CSS_PATH = os.path.join(cache_path, '%s_sprite.css' % (emojiset,))
        sprite_css_file = open(SPRITE_CSS_PATH, 'w')
        sprite_css_file.write(SPRITE_CSS_FILE_TEMPLATE % {'emojiset': emojiset,
                                                          'emoji_positions': emoji_positions,
                                                          })
        sprite_css_file.close()

def setup_emoji_farm(cache_path: str, emoji_data: List[Dict[str, Any]]) -> None:
    for emojiset in EMOJISETS:
        # Copy individual emoji images from npm packages.
        src_emoji_farm = os.path.join(
            NODE_MODULES_PATH, 'emoji-datasource-' + emojiset, 'img', emojiset, '64', '*')
        target_emoji_farm = os.path.join(cache_path, 'images-' + emojiset + '-64')
        run(['mkdir', '-p', target_emoji_farm])
        run(['cp', '-RPp', src_emoji_farm, target_emoji_farm], shell=True)

        # Copy zulip.png to the emoji farm.
        zulip_image = "{}/static/assets/zulip-emoji/*".format(ZULIP_PATH)
        run(['cp', '-RPp', zulip_image, target_emoji_farm], shell=True)

        # Copy spritesheets.
        emoji_data_path = os.path.join(NODE_MODULES_PATH, 'emoji-datasource-' + emojiset)
        input_sprite_sheet = os.path.join(emoji_data_path, 'img', emojiset, 'sheets-256', '64.png')
        output_sprite_sheet = os.path.join(cache_path, 'sheet_%s_64.png' % (emojiset,))
        run(['cp', input_sprite_sheet, output_sprite_sheet])

    generate_sprite_css_files(cache_path, emoji_data)

def setup_old_emoji_farm(cache_path: str, emoji_map: Dict[str, str]) -> None:
    # Code for setting up old emoji farm.
    # Some image files in the old emoji farm had a different name than in the new emoji
    # farm. `remapped_emojis` is a map that contains a mapping of their name in the old
    # emoji farm to their name in the new emoji farm.
    remapped_emojis = {
        "0023": "0023-20e3",    # Hash
        "0030": "0030-20e3",    # Zero
        "0031": "0031-20e3",    # One
        "0032": "0032-20e3",    # Two
        "0033": "0033-20e3",    # Three
        "0034": "0034-20e3",    # Four
        "0035": "0035-20e3",    # Five
        "0036": "0036-20e3",    # Six
        "0037": "0037-20e3",    # Seven
        "0038": "0038-20e3",    # Eight
        "0039": "0039-20e3",    # Nine
        "1f48f": "1f469-200d-2764-200d-1f48b-200d-1f468",    # Couple kiss
        "1f491": "1f469-200d-2764-200d-1f468",  # Couple with heart
    }

    os.chdir(cache_path)
    emoji_cache_path = os.path.join(cache_path, 'images', 'emoji')
    unicode_emoji_cache_path = os.path.join(cache_path, 'images', 'emoji', 'unicode')
    google_emoji_cache_path = os.path.join(cache_path, 'images-google-64')
    run(['mkdir', '-p', emoji_cache_path])
    run(['mkdir', '-p', unicode_emoji_cache_path])

    # Symlink zulip.png image file.
    image_file_path = os.path.join(google_emoji_cache_path, 'zulip.png')
    symlink_path = os.path.join(emoji_cache_path, 'zulip.png')
    os.symlink(image_file_path, symlink_path)

    unicode_symlink_path = os.path.join(unicode_emoji_cache_path, 'zulip.png')
    os.symlink(image_file_path, unicode_symlink_path)

    for name, codepoint in emoji_map.items():
        mapped_codepoint = remapped_emojis.get(codepoint, codepoint)
        image_file_path = os.path.join(google_emoji_cache_path, '{}.png'.format(mapped_codepoint))
        symlink_path = os.path.join(emoji_cache_path, '{}.png'.format(name))
        os.symlink(image_file_path, symlink_path)
        try:
            # `emoji_map` contains duplicate entries for the same codepoint with different
            # names. So creation of symlink for <codepoint>.png may throw `FileExistsError`.
            unicode_symlink_path = os.path.join(unicode_emoji_cache_path, '{}.png'.format(codepoint))
            os.symlink(image_file_path, unicode_symlink_path)
        except FileExistsError:
            pass

def generate_map_files(cache_path: str, emoji_catalog: Dict[str, List[str]]) -> None:
    # This function generates the various data files consumed by webapp, mobile apps, bugdown etc.
    names = emoji_names_for_picker(EMOJI_NAME_MAPS)
    codepoint_to_name = generate_codepoint_to_name_map(EMOJI_NAME_MAPS)
    name_to_codepoint = generate_name_to_codepoint_map(EMOJI_NAME_MAPS)

    EMOJI_CODES_FILE_PATH = os.path.join(cache_path, 'emoji_codes.js')
    with open(EMOJI_CODES_FILE_PATH, 'w') as emoji_codes_file:
        emoji_codes_file.write(EMOJI_CODES_FILE_TEMPLATE % {
            'names': names,
            'name_to_codepoint': name_to_codepoint,
            'codepoint_to_name': codepoint_to_name,
            'emoji_catalog': emoji_catalog,
        })

    NAME_TO_CODEPOINT_PATH = os.path.join(cache_path, 'name_to_codepoint.json')
    with open(NAME_TO_CODEPOINT_PATH, 'w') as name_to_codepoint_file:
        name_to_codepoint_file.write(ujson.dumps(name_to_codepoint))

    CODEPOINT_TO_NAME_PATH = os.path.join(cache_path, 'codepoint_to_name.json')
    with open(CODEPOINT_TO_NAME_PATH, 'w') as codepoint_to_name_file:
        codepoint_to_name_file.write(ujson.dumps(codepoint_to_name))

def dump_emojis(cache_path: str) -> None:
    with open('emoji_map.json') as emoji_map_file:
        emoji_map = ujson.load(emoji_map_file)

    # `emoji.json` or any other data file can be sourced from any of the supported
    # emojiset packages, they all contain the same data files.
    EMOJI_DATA_FILE_PATH = os.path.join(NODE_MODULES_PATH, 'emoji-datasource-google', 'emoji.json')
    with open(EMOJI_DATA_FILE_PATH) as emoji_data_file:
        emoji_data = ujson.load(emoji_data_file)
    emoji_catalog = generate_emoji_catalog(emoji_data, EMOJI_NAME_MAPS)

    # Setup emoji farms.
    run(['rm', '-rf', cache_path])
    setup_emoji_farm(cache_path, emoji_data)
    setup_old_emoji_farm(cache_path, emoji_map)

    # Generate various map files.
    generate_map_files(cache_path, emoji_catalog)

if __name__ == "__main__":
    main()