import ast
import base64
import copy
import functools
import io
import json
import re
from datetime import datetime
from pathlib import Path

import yaml
from PIL import Image

import modules.shared as shared
from modules.extensions import apply_extensions
from modules.html_generator import chat_html_wrapper, make_thumbnail
from modules.logging_colors import logger
from modules.text_generation import (generate_reply, get_encoded_length,
                                     get_max_prompt_length)
from modules.utils import replace_all


def get_turn_substrings(state, instruct=False):
    if instruct:
        if 'turn_template' not in state or state['turn_template'] == '':
            template = '<|user|>\n<|user-message|>\n<|bot|>\n<|bot-message|>\n'
        else:
            template = state['turn_template'].replace(r'\n', '\n')
    else:
        template = '<|user|>: <|user-message|>\n<|bot|>: <|bot-message|>\n'

    replacements = {
        '<|user|>': state['name1_instruct' if instruct else 'name1'].strip(),
        '<|bot|>': state['name2_instruct' if instruct else 'name2'].strip(),
    }

    output = {
        'user_turn': template.split('<|bot|>')[0],
        'bot_turn': '<|bot|>' + template.split('<|bot|>')[1],
        'user_turn_stripped': template.split('<|bot|>')[0].split('<|user-message|>')[0],
        'bot_turn_stripped': '<|bot|>' + template.split('<|bot|>')[1].split('<|bot-message|>')[0],
    }

    for k in output:
        output[k] = replace_all(output[k], replacements)

    return output


def generate_chat_prompt(user_input, state, **kwargs):
    impersonate = kwargs.get('impersonate', False)
    _continue = kwargs.get('_continue', False)
    also_return_rows = kwargs.get('also_return_rows', False)
    history = kwargs.get('history', shared.history)['internal']
    is_instruct = state['mode'] == 'instruct'

    # Find the maximum prompt size
    max_length = min(get_max_prompt_length(state), state['chat_prompt_size'])
    all_substrings = {
        'chat': get_turn_substrings(state, instruct=False),
        'instruct': get_turn_substrings(state, instruct=True)
    }

    substrings = all_substrings['instruct' if is_instruct else 'chat']

    # Create the template for "chat-instruct" mode
    if state['mode'] == 'chat-instruct':
        wrapper = ''
        command = state['chat-instruct_command'].replace('<|character|>', state['name2'] if not impersonate else state['name1'])
        wrapper += state['context_instruct']
        wrapper += all_substrings['instruct']['user_turn'].replace('<|user-message|>', command)
        wrapper += all_substrings['instruct']['bot_turn_stripped']
        if impersonate:
            wrapper += substrings['user_turn_stripped'].rstrip(' ')
        elif _continue:
            wrapper += apply_extensions("bot_prefix", substrings['bot_turn_stripped'])
            wrapper += history[-1][1]
        else:
            wrapper += apply_extensions("bot_prefix", substrings['bot_turn_stripped'].rstrip(' '))
    else:
        wrapper = '<|prompt|>'

    # Build the prompt
    min_rows = 3
    i = len(history) - 1
    rows = [state['context_instruct'] if is_instruct else f"{state['context'].strip()}\n"]
    while i >= 0 and get_encoded_length(wrapper.replace('<|prompt|>', ''.join(rows))) < max_length:
        if _continue and i == len(history) - 1:
            if state['mode'] != 'chat-instruct':
                rows.insert(1, substrings['bot_turn_stripped'] + history[i][1].strip())
        else:
            rows.insert(1, substrings['bot_turn'].replace('<|bot-message|>', history[i][1].strip()))

        string = history[i][0]
        if string not in ['', '<|BEGIN-VISIBLE-CHAT|>']:
            rows.insert(1, replace_all(substrings['user_turn'], {'<|user-message|>': string.strip(), '<|round|>': str(i)}))

        i -= 1

    if impersonate:
        if state['mode'] == 'chat-instruct':
            min_rows = 1
        else:
            min_rows = 2
            rows.append(substrings['user_turn_stripped'].rstrip(' '))
    elif not _continue:
        # Add the user message
        if len(user_input) > 0:
            rows.append(replace_all(substrings['user_turn'], {'<|user-message|>': user_input.strip(), '<|round|>': str(len(history))}))

        # Add the character prefix
        if state['mode'] != 'chat-instruct':
            rows.append(apply_extensions("bot_prefix", substrings['bot_turn_stripped'].rstrip(' ')))

    while len(rows) > min_rows and get_encoded_length(wrapper.replace('<|prompt|>', ''.join(rows))) >= max_length:
        rows.pop(1)

    prompt = wrapper.replace('<|prompt|>', ''.join(rows))
    if also_return_rows:
        return prompt, rows
    else:
        return prompt


def get_stopping_strings(state):
    stopping_strings = []
    if state['mode'] in ['instruct', 'chat-instruct']:
        stopping_strings += [
            state['turn_template'].split('<|user-message|>')[1].split('<|bot|>')[0] + '<|bot|>',
            state['turn_template'].split('<|bot-message|>')[1] + '<|user|>'
        ]

        replacements = {
            '<|user|>': state['name1_instruct'],
            '<|bot|>': state['name2_instruct']
        }

        for i in range(len(stopping_strings)):
            stopping_strings[i] = replace_all(stopping_strings[i], replacements).rstrip(' ').replace(r'\n', '\n')

    if state['mode'] in ['chat', 'chat-instruct']:
        stopping_strings += [
            f"\n{state['name1']}:",
            f"\n{state['name2']}:"
        ]

    stopping_strings += ast.literal_eval(f"[{state['custom_stopping_strings']}]")
    return stopping_strings


def extract_message_from_reply(reply, state):
    next_character_found = False
    stopping_strings = get_stopping_strings(state)

    if state['stop_at_newline']:
        lines = reply.split('\n')
        reply = lines[0].strip()
        if len(lines) > 1:
            next_character_found = True
    else:
        for string in stopping_strings:
            idx = reply.find(string)
            if idx != -1:
                reply = reply[:idx]
                next_character_found = True

        # If something like "\nYo" is generated just before "\nYou:"
        # is completed, trim it
        if not next_character_found:
            for string in stopping_strings:
                for j in range(len(string) - 1, 0, -1):
                    if reply[-j:] == string[:j]:
                        reply = reply[:-j]
                        break
                else:
                    continue

                break

    return reply, next_character_found


def chatbot_wrapper(text, history, state, regenerate=False, _continue=False, loading_message=True):
    output = copy.deepcopy(history)
    output = apply_extensions('history', output)
    if shared.model_name == 'None' or shared.model is None:
        logger.error("No model is loaded! Select one in the Model tab.")
        yield output
        return

    # Defining some variables
    just_started = True
    visible_text = None
    eos_token = '\n' if state['stop_at_newline'] else None
    stopping_strings = get_stopping_strings(state)

    # Preparing the input
    if not any((regenerate, _continue)):
        text, visible_text = apply_extensions('input_hijack', text, visible_text)
        if visible_text is None:
            visible_text = text

        text = apply_extensions('input', text)
        # *Is typing...*
        if loading_message:
            yield {'visible': output['visible'] + [[visible_text, shared.processing_message]], 'internal': output['internal']}
    else:
        text, visible_text = output['internal'][-1][0], output['visible'][-1][0]
        if regenerate:
            output['visible'].pop()
            output['internal'].pop()
            # *Is typing...*
            if loading_message:
                yield {'visible': output['visible'] + [[visible_text, shared.processing_message]], 'internal': output['internal']}
        elif _continue:
            last_reply = [output['internal'][-1][1], output['visible'][-1][1]]
            if loading_message:
                yield {'visible': output['visible'][:-1] + [[visible_text, last_reply[1] + '...']], 'internal': output['internal']}

    # Generating the prompt
    kwargs = {
        '_continue': _continue,
        'history': output,
    }

    prompt = apply_extensions('custom_generate_chat_prompt', text, state, **kwargs)
    if prompt is None:
        prompt = generate_chat_prompt(text, state, **kwargs)

    # Generate
    cumulative_reply = ''
    for i in range(state['chat_generation_attempts']):
        reply = None
        for j, reply in enumerate(generate_reply(prompt + cumulative_reply, state, eos_token=eos_token, stopping_strings=stopping_strings, is_chat=True)):
            reply = cumulative_reply + reply

            # Extract the reply
            reply, next_character_found = extract_message_from_reply(reply, state)
            visible_reply = re.sub("(<USER>|<user>|{{user}})", state['name1'], reply)
            visible_reply = apply_extensions("output", visible_reply)

            # We need this global variable to handle the Stop event,
            # otherwise gradio gets confused
            if shared.stop_everything:
                yield output
                return

            if just_started:
                just_started = False
                if not _continue:
                    output['internal'].append(['', ''])
                    output['visible'].append(['', ''])

            if _continue:
                output['internal'][-1] = [text, last_reply[0] + reply]
                output['visible'][-1] = [visible_text, last_reply[1] + visible_reply]
                if state['stream']:
                    yield output
            elif not (j == 0 and visible_reply.strip() == ''):
                output['internal'][-1] = [text, reply.lstrip(' ')]
                output['visible'][-1] = [visible_text, visible_reply.lstrip(' ')]
                if state['stream']:
                    yield output

            if next_character_found:
                break

        if reply in [None, cumulative_reply]:
            break
        else:
            cumulative_reply = reply

    yield output


def impersonate_wrapper(text, start_with, state):
    if shared.model_name == 'None' or shared.model is None:
        logger.error("No model is loaded! Select one in the Model tab.")
        yield ''
        return

    # Defining some variables
    cumulative_reply = ''
    eos_token = '\n' if state['stop_at_newline'] else None
    prompt = generate_chat_prompt('', state, impersonate=True)
    stopping_strings = get_stopping_strings(state)

    yield text + '...'
    cumulative_reply = text
    for i in range(state['chat_generation_attempts']):
        reply = None
        for reply in generate_reply(prompt + cumulative_reply, state, eos_token=eos_token, stopping_strings=stopping_strings, is_chat=True):
            reply = cumulative_reply + reply
            reply, next_character_found = extract_message_from_reply(reply, state)
            yield reply.lstrip(' ')
            if shared.stop_everything:
                return

            if next_character_found:
                break

        if reply in [None, cumulative_reply]:
            break
        else:
            cumulative_reply = reply

    yield cumulative_reply.lstrip(' ')


def generate_chat_reply(text, history, state, regenerate=False, _continue=False, loading_message=True):
    if regenerate or _continue:
        text = ''
        if (len(history['visible']) == 1 and not history['visible'][0][0]) or len(history['internal']) == 0:
            yield history
            return

    for history in chatbot_wrapper(text, history, state, regenerate=regenerate, _continue=_continue, loading_message=loading_message):
        yield history


# Same as above but returns HTML for the UI
def generate_chat_reply_wrapper(text, start_with, state, regenerate=False, _continue=False):
    if start_with != '' and _continue == False:
        if regenerate == True:
            text = remove_last_message()
            regenerate = False

        _continue = True
        send_dummy_message(text)
        send_dummy_reply(start_with)

    for i, history in enumerate(generate_chat_reply(text, shared.history, state, regenerate, _continue, loading_message=True)):
        if i != 0:
            shared.history = copy.deepcopy(history)

        yield chat_html_wrapper(history['visible'], state['name1'], state['name2'], state['mode'], state['chat_style'])


def remove_last_message():
    if len(shared.history['visible']) > 0 and shared.history['internal'][-1][0] != '<|BEGIN-VISIBLE-CHAT|>':
        last = shared.history['visible'].pop()
        shared.history['internal'].pop()
    else:
        last = ['', '']

    return last[0]


def send_last_reply_to_input():
    if len(shared.history['internal']) > 0:
        return shared.history['internal'][-1][1]
    else:
        return ''


def replace_last_reply(text):
    if len(shared.history['visible']) > 0:
        shared.history['visible'][-1][1] = text
        shared.history['internal'][-1][1] = apply_extensions("input", text)


def send_dummy_message(text):
    shared.history['visible'].append([text, ''])
    shared.history['internal'].append([apply_extensions("input", text), ''])


def send_dummy_reply(text):
    if len(shared.history['visible']) > 0 and not shared.history['visible'][-1][1] == '':
        shared.history['visible'].append(['', ''])
        shared.history['internal'].append(['', ''])

    shared.history['visible'][-1][1] = text
    shared.history['internal'][-1][1] = apply_extensions("input", text)


def clear_chat_log(greeting, mode):
    shared.history['visible'] = []
    shared.history['internal'] = []

    if mode != 'instruct':
        if greeting != '':
            shared.history['internal'] += [['<|BEGIN-VISIBLE-CHAT|>', greeting]]
            shared.history['visible'] += [['', apply_extensions("output", greeting)]]

        save_history(mode)


def redraw_html(name1, name2, mode, style, reset_cache=False):
    return chat_html_wrapper(shared.history['visible'], name1, name2, mode, style, reset_cache=reset_cache)


def tokenize_dialogue(dialogue, name1, name2):
    history = []
    messages = []
    dialogue = re.sub('<START>', '', dialogue)
    dialogue = re.sub('<start>', '', dialogue)
    dialogue = re.sub('(\n|^)[Aa]non:', '\\1You:', dialogue)
    dialogue = re.sub('(\n|^)\[CHARACTER\]:', f'\\g<1>{name2}:', dialogue)
    idx = [m.start() for m in re.finditer(f"(^|\n)({re.escape(name1)}|{re.escape(name2)}):", dialogue)]
    if len(idx) == 0:
        return history

    for i in range(len(idx) - 1):
        messages.append(dialogue[idx[i]:idx[i + 1]].strip())

    messages.append(dialogue[idx[-1]:].strip())
    entry = ['', '']
    for i in messages:
        if i.startswith(f'{name1}:'):
            entry[0] = i[len(f'{name1}:'):].strip()
        elif i.startswith(f'{name2}:'):
            entry[1] = i[len(f'{name2}:'):].strip()
            if not (len(entry[0]) == 0 and len(entry[1]) == 0):
                history.append(entry)

            entry = ['', '']

    print("\033[1;32;1m\nDialogue tokenized to:\033[0;37;0m\n", end='')
    for row in history:
        for column in row:
            print("\n")
            for line in column.strip().split('\n'):
                print("|  " + line + "\n")

            print("|\n")
        print("------------------------------")

    return history


def save_history(mode, timestamp=False):
    # Instruct mode histories should not be saved as if
    # Alpaca or Vicuna were characters
    if mode == 'instruct':
        if not timestamp:
            return

        fname = f"Instruct_{datetime.now().strftime('%Y%m%d-%H%M%S')}.json"
    else:
        if shared.character == 'None':
            return

        if timestamp:
            fname = f"{shared.character}_{datetime.now().strftime('%Y%m%d-%H%M%S')}.json"
        else:
            fname = f"{shared.character}_persistent.json"

    if not Path('logs').exists():
        Path('logs').mkdir()

    with open(Path(f'logs/{fname}'), 'w', encoding='utf-8') as f:
        f.write(json.dumps({'data': shared.history['internal'], 'data_visible': shared.history['visible']}, indent=2))


def load_history(file, name1, name2):
    file = file.decode('utf-8')
    try:
        j = json.loads(file)
        if 'data' in j:
            shared.history['internal'] = j['data']
            if 'data_visible' in j:
                shared.history['visible'] = j['data_visible']
            else:
                shared.history['visible'] = copy.deepcopy(shared.history['internal'])
    except:
        shared.history['internal'] = tokenize_dialogue(file, name1, name2)
        shared.history['visible'] = copy.deepcopy(shared.history['internal'])


def replace_character_names(text, name1, name2):
    text = text.replace('{{user}}', name1).replace('{{char}}', name2)
    return text.replace('<USER>', name1).replace('<BOT>', name2)


def build_pygmalion_style_context(data):
    context = ""
    if 'char_persona' in data and data['char_persona'] != '':
        context += f"{data['char_name']}'s Persona: {data['char_persona']}\n"

    if 'world_scenario' in data and data['world_scenario'] != '':
        context += f"Scenario: {data['world_scenario']}\n"

    context = f"{context.strip()}\n<START>\n"
    return context


def generate_pfp_cache(character):
    cache_folder = Path("cache")
    if not cache_folder.exists():
        cache_folder.mkdir()

    for path in [Path(f"characters/{character}.{extension}") for extension in ['png', 'jpg', 'jpeg']]:
        if path.exists():
            img = make_thumbnail(Image.open(path))
            img.save(Path('cache/pfp_character.png'), format='PNG')
            return img

    return None


def load_character(character, name1, name2, instruct=False):
    shared.character = character
    context = greeting = turn_template = ""
    greeting_field = 'greeting'
    picture = None

    # Deleting the profile picture cache, if any
    if Path("cache/pfp_character.png").exists():
        Path("cache/pfp_character.png").unlink()

    if character != 'None':
        folder = 'characters' if not instruct else 'characters/instruction-following'
        picture = generate_pfp_cache(character)
        for extension in ["yml", "yaml", "json"]:
            filepath = Path(f'{folder}/{character}.{extension}')
            if filepath.exists():
                break

        file_contents = open(filepath, 'r', encoding='utf-8').read()
        data = json.loads(file_contents) if extension == "json" else yaml.safe_load(file_contents)

        # Finding the bot's name
        for k in ['name', 'bot', '<|bot|>', 'char_name']:
            if k in data and data[k] != '':
                name2 = data[k]
                break

        # Find the user name (if any)
        for k in ['your_name', 'user', '<|user|>']:
            if k in data and data[k] != '':
                name1 = data[k]
                break

        for field in ['context', 'greeting', 'example_dialogue', 'char_persona', 'char_greeting', 'world_scenario']:
            if field in data:
                data[field] = replace_character_names(data[field], name1, name2)

        if 'context' in data:
            context = data['context']
            if not instruct:
                context = context.strip() + '\n'
        elif "char_persona" in data:
            context = build_pygmalion_style_context(data)
            greeting_field = 'char_greeting'

        if 'example_dialogue' in data:
            context += f"{data['example_dialogue'].strip()}\n"

        if greeting_field in data:
            greeting = data[greeting_field]

        if 'turn_template' in data:
            turn_template = data['turn_template']

    else:
        context = shared.settings['context']
        name2 = shared.settings['name2']
        greeting = shared.settings['greeting']
        turn_template = shared.settings['turn_template']

    if not instruct:
        shared.history['internal'] = []
        shared.history['visible'] = []
        if shared.character != 'None' and Path(f'logs/{shared.character}_persistent.json').exists():
            load_history(open(Path(f'logs/{shared.character}_persistent.json'), 'rb').read(), name1, name2)
        else:
            # Insert greeting if it exists
            if greeting != "":
                shared.history['internal'] += [['<|BEGIN-VISIBLE-CHAT|>', greeting]]
                shared.history['visible'] += [['', apply_extensions("output", greeting)]]

            # Create .json log files since they don't already exist
            save_history('instruct' if instruct else 'chat')

    return name1, name2, picture, greeting, context, repr(turn_template)[1:-1]


@functools.cache
def load_character_memoized(character, name1, name2, instruct=False):
    return load_character(character, name1, name2, instruct=instruct)


def upload_character(json_file, img, tavern=False):
    json_file = json_file if type(json_file) == str else json_file.decode('utf-8')
    data = json.loads(json_file)
    outfile_name = data["char_name"]
    i = 1
    while Path(f'characters/{outfile_name}.json').exists():
        outfile_name = f'{data["char_name"]}_{i:03d}'
        i += 1

    if tavern:
        outfile_name = f'TavernAI-{outfile_name}'

    with open(Path(f'characters/{outfile_name}.json'), 'w', encoding='utf-8') as f:
        f.write(json_file)

    if img is not None:
        img = Image.open(io.BytesIO(img))
        img.save(Path(f'characters/{outfile_name}.png'))

    logger.info(f'New character saved to "characters/{outfile_name}.json".')
    return outfile_name


def upload_tavern_character(img, name1, name2):
    _img = Image.open(io.BytesIO(img))
    _img.getexif()
    decoded_string = base64.b64decode(_img.info['chara'])
    _json = json.loads(decoded_string)
    _json = {"char_name": _json['name'], "char_persona": _json['description'], "char_greeting": _json["first_mes"], "example_dialogue": _json['mes_example'], "world_scenario": _json['scenario']}
    return upload_character(json.dumps(_json), img, tavern=True)


def upload_your_profile_picture(img):
    cache_folder = Path("cache")
    if not cache_folder.exists():
        cache_folder.mkdir()

    if img is None:
        if Path("cache/pfp_me.png").exists():
            Path("cache/pfp_me.png").unlink()
    else:
        img = make_thumbnail(img)
        img.save(Path('cache/pfp_me.png'))
        logger.info('Profile picture saved to "cache/pfp_me.png"')


def delete_file(path):
    if path.exists():
        logger.warning(f'Deleting {path}')
        path.unlink(missing_ok=True)


def save_character(name, greeting, context, picture, filename, instruct=False):
    if filename == "":
        logger.error("The filename is empty, so the character will not be saved.")
        return

    folder = 'characters' if not instruct else 'characters/instruction-following'
    data = {
        'name': name,
        'greeting': greeting,
        'context': context,
    }

    data = {k: v for k, v in data.items() if v}  # Strip falsy
    filepath = Path(f'{folder}/{filename}.yaml')
    with filepath.open('w') as f:
        yaml.dump(data, f, sort_keys=False)

    logger.info(f'Wrote {filepath}')
    path_to_img = Path(f'{folder}/{filename}.png')
    if picture and not instruct:
        picture.save(path_to_img)
        logger.info(f'Wrote {path_to_img}')
    elif path_to_img.exists():
        delete_file(path_to_img)


def delete_character(name, instruct=False):
    folder = 'characters' if not instruct else 'characters/instruction-following'
    for extension in ["yml", "yaml", "json"]:
        delete_file(Path(f'{folder}/{name}.{extension}'))

    delete_file(Path(f'{folder}/{name}.png'))