import time
from datetime import datetime

from llm_server import opts
from llm_server.database.database import get_distinct_ips_24h, sum_column
from llm_server.helpers import deep_sort, round_up_base
from llm_server.llm.info import get_running_model
from llm_server.netdata import get_power_states
from llm_server.routes.cache import redis
from llm_server.routes.queue import priority_queue
from llm_server.routes.stats import get_active_gen_workers, get_total_proompts, server_start_time


def calculate_wait_time(gen_time_calc, proompters_in_queue, concurrent_gens, active_gen_workers):
    if active_gen_workers < concurrent_gens:
        return 0
    elif active_gen_workers >= concurrent_gens:
        # Calculate how long it will take to complete the currently running gens and the queued requests.
        # If the proompters in the queue are equal to the number of workers, just use the calculated generation time.
        # Otherwise, use how many requests we can process concurrently times the calculated generation time. Then, round
        # that number up to the nearest base gen_time_calc (ie. if gen_time_calc is 8 and the calculated number is 11.6, we will get 18). Finally,
        # Add gen_time_calc to the time to account for the currently running generations.
        # This assumes that all active workers will finish at the same time, which is unlikely.
        # Regardless, this is the most accurate estimate we can get without tracking worker elapsed times.
        proompters_in_queue_wait_time = gen_time_calc if (proompters_in_queue / concurrent_gens) <= 1 \
            else round_up_base(((proompters_in_queue / concurrent_gens) * gen_time_calc), base=gen_time_calc)
        return proompters_in_queue_wait_time + gen_time_calc if active_gen_workers > 0 else 0
    elif proompters_in_queue == 0 and active_gen_workers == 0:
        # No queue, no workers
        return 0
    else:
        # No queue
        return gen_time_calc


# TODO: have routes/__init__.py point to the latest API version generate_stats()

def generate_stats(regen: bool = False):
    if not regen:
        c = redis.get('proxy_stats', dict)
        if c:
            return c

    model_name, error = get_running_model()  # will return False when the fetch fails
    if isinstance(model_name, bool):
        online = False
    else:
        online = True
        redis.set('running_model', model_name)

    # t = elapsed_times.copy()  # copy since we do multiple operations and don't want it to change
    # if len(t) == 0:
    #     estimated_wait = 0
    # else:
    #     waits = [elapsed for end, elapsed in t]
    #     estimated_wait = int(sum(waits) / len(waits))

    active_gen_workers = get_active_gen_workers()
    proompters_in_queue = len(priority_queue)

    # This is so wildly inaccurate it's disabled until I implement stats reporting into VLLM.
    # estimated_avg_tps = redis.get('estimated_avg_tps', float, default=0)

    average_generation_time = redis.get('average_generation_elapsed_sec', float, default=0)
    estimated_wait_sec = calculate_wait_time(average_generation_time, proompters_in_queue, opts.concurrent_gens, active_gen_workers)

    if opts.netdata_root:
        netdata_stats = {}
        power_states = get_power_states()
        for gpu, power_state in power_states.items():
            netdata_stats[gpu] = {
                'power_state': power_state,
                # 'wh_wasted_1_hr': get_gpu_wh(int(gpu.strip('gpu')))
            }
    else:
        netdata_stats = {}

    base_client_api = redis.get('base_client_api', str)
    proompters_5_min = redis.get('proompters_5_min', int)

    output = {
        'stats': {
            'proompters': {
                '5_min': proompters_5_min,
                '24_hrs': get_distinct_ips_24h(),
            },
            'proompts_total': get_total_proompts() if opts.show_num_prompts else None,
            'uptime': int((datetime.now() - server_start_time).total_seconds()) if opts.show_uptime else None,
            'average_generation_elapsed_sec': int(average_generation_time),
            # 'estimated_avg_tps': estimated_avg_tps,
            'tokens_generated': sum_column('prompts', 'response_tokens') if opts.show_total_output_tokens else None,
            'nvidia': netdata_stats
        },
        'online': online,
        'endpoints': {
            'blocking': f'https://{base_client_api}',
            'streaming': f'wss://{base_client_api}/v1/stream' if opts.enable_streaming else None,
        },
        'queue': {
            'processing': active_gen_workers,
            'queued': proompters_in_queue,
            'estimated_wait_sec': int(estimated_wait_sec),
        },
        'timestamp': int(time.time()),
        'config': {
            'gatekeeper': 'none' if opts.auth_required is False else 'token',
            'context_size': opts.context_size,
            'concurrent': opts.concurrent_gens,
            'model': opts.manual_model_name if opts.manual_model_name else model_name,
            'mode': opts.mode,
            'simultaneous_requests_per_ip': opts.simultaneous_requests_per_ip,
        },
        'keys': {
            'openaiKeys': '∞',
            'anthropicKeys': '∞',
        },
        'backend_info': redis.get_dict('backend_info') if opts.show_backend_info else None,
    }
    result = deep_sort(output)

    # It may take a bit to get the base client API, so don't cache until then.
    if base_client_api:
        redis.set_dict('proxy_stats', result)  # Cache with no expiry
    return result