import json
import sqlite3
import time
from pathlib import Path

import tiktoken

from llm_server import opts

tokenizer = tiktoken.get_encoding("cl100k_base")


def init_db():
    if not Path(opts.database_path).exists():
        conn = sqlite3.connect(opts.database_path)
        c = conn.cursor()
        c.execute('''
            CREATE TABLE prompts (
                ip TEXT,
                token TEXT DEFAULT NULL,
                model TEXT,
                backend_mode TEXT,
                backend_url TEXT,
                request_url TEXT,
                generation_time FLOAT,
                prompt TEXT,
                prompt_tokens INTEGER,
                response TEXT,
                response_tokens INTEGER,
                response_status INTEGER,
                parameters TEXT CHECK (parameters IS NULL OR json_valid(parameters)),
                headers TEXT CHECK (headers IS NULL OR json_valid(headers)),
                timestamp INTEGER
            )
        ''')
        c.execute('''
            CREATE TABLE token_auth (
                token TEXT UNIQUE,
                type TEXT NOT NULL,
                priority INTEGER default 9999,
                uses INTEGER default 0,
                max_uses INTEGER,
                expire INTEGER,
                disabled BOOLEAN default 0
            )
        ''')
        conn.commit()
        conn.close()


def log_prompt(ip, token, prompt, response, gen_time, parameters, headers, backend_response_code, request_url, response_tokens: int = None, is_error: bool = False):
    prompt_tokens = len(tokenizer.encode(prompt))

    if not is_error:
        if not response_tokens:
            response_tokens = len(tokenizer.encode(response, disallowed_special=()))
    else:
        response_tokens = None

    # Sometimes we may want to insert null into the DB, but
    # usually we want to insert a float.
    if gen_time:
        gen_time = round(gen_time, 3)
    if is_error:
        gen_time = None

    if not opts.log_prompts:
        prompt = None

    if not opts.log_prompts and not is_error:
        # TODO: test and verify this works as expected
        response = None

    timestamp = int(time.time())
    conn = sqlite3.connect(opts.database_path)
    c = conn.cursor()
    c.execute("INSERT INTO prompts VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)",
              (ip, token, opts.running_model, opts.mode, opts.backend_url, request_url, gen_time, prompt, prompt_tokens, response, response_tokens, backend_response_code, json.dumps(parameters), json.dumps(headers), timestamp))
    conn.commit()
    conn.close()


def is_valid_api_key(api_key):
    conn = sqlite3.connect(opts.database_path)
    cursor = conn.cursor()
    cursor.execute("SELECT token, uses, max_uses, expire, disabled FROM token_auth WHERE token = ?", (api_key,))
    row = cursor.fetchone()
    if row is not None:
        token, uses, max_uses, expire, disabled = row
        disabled = bool(disabled)
        if (uses is None or uses < max_uses) and (expire is None or expire > time.time()) and not disabled:
            return True
    return False


def increment_uses(api_key):
    conn = sqlite3.connect(opts.database_path)
    cursor = conn.cursor()
    cursor.execute("SELECT token FROM token_auth WHERE token = ?", (api_key,))
    row = cursor.fetchone()
    if row is not None:
        cursor.execute("UPDATE token_auth SET uses = COALESCE(uses, 0) + 1 WHERE token = ?", (api_key,))
        conn.commit()
        return True
    return False


def get_number_of_rows(table_name):
    conn = sqlite3.connect(opts.database_path)
    cur = conn.cursor()
    cur.execute(f'SELECT COUNT(*) FROM {table_name}')
    result = cur.fetchone()
    conn.close()
    return result[0]


def average_column(table_name, column_name):
    conn = sqlite3.connect(opts.database_path)
    cursor = conn.cursor()
    cursor.execute(f"SELECT AVG({column_name}) FROM {table_name}")
    result = cursor.fetchone()
    conn.close()
    return result[0]


def average_column_for_model(table_name, column_name, model_name):
    conn = sqlite3.connect(opts.database_path)
    cursor = conn.cursor()
    cursor.execute(f"SELECT AVG({column_name}) FROM {table_name} WHERE model = ?", (model_name,))
    result = cursor.fetchone()
    conn.close()
    return result[0]


def weighted_average_column_for_model(table_name, column_name, model_name, backend_name, backend_url, exclude_zeros: bool = False):
    conn = sqlite3.connect(opts.database_path)
    cursor = conn.cursor()
    # cursor.execute(f"SELECT DISTINCT model, backend_mode FROM {table_name}")
    # models_backends = [(row[0], row[1]) for row in cursor.fetchall()]
    #
    # model_averages = {}
    # for model, backend in models_backends:
    #     if backend != backend_name:
    #         continue
    cursor.execute(f"SELECT {column_name}, ROWID FROM {table_name} WHERE model = ? AND backend_mode = ? AND backend_url = ? ORDER BY ROWID DESC", (model_name, backend_name, backend_url))
    results = cursor.fetchall()

    # if not results:
    #     continue

    total_weight = 0
    weighted_sum = 0
    for i, (value, rowid) in enumerate(results):
        if value is None or (exclude_zeros and value == 0):
            continue
        weight = i + 1
        total_weight += weight
        weighted_sum += weight * value

    # if total_weight == 0:
    #     continue

    if total_weight > 0:
        # Avoid division by zero
        calculated_avg = weighted_sum / total_weight
    else:
        calculated_avg = 0

    conn.close()

    return calculated_avg


def sum_column(table_name, column_name):
    conn = sqlite3.connect(opts.database_path)
    cursor = conn.cursor()
    cursor.execute(f"SELECT SUM({column_name}) FROM {table_name}")
    result = cursor.fetchone()
    conn.close()
    return result[0] if result[0] else 0


def get_distinct_ips_24h():
    # Get the current time and subtract 24 hours (in seconds)
    past_24_hours = int(time.time()) - 24 * 60 * 60
    conn = sqlite3.connect(opts.database_path)
    cur = conn.cursor()
    cur.execute("SELECT COUNT(DISTINCT ip) FROM prompts WHERE timestamp >= ?", (past_24_hours,))
    result = cur.fetchone()
    conn.close()
    return result[0] if result else 0