import time

import asyncpg
import asyncpg.exceptions

from pluralkit import stats
from pluralkit.bot import logger

async def connect():
    while True:
        try:
            return await asyncpg.create_pool(user="postgres", password="postgres", database="postgres", host="db")
        except (ConnectionError, asyncpg.exceptions.CannotConnectNowError):
            pass


def db_wrap(func):
    async def inner(*args, **kwargs):
        before = time.perf_counter()
        try:
            res = await func(*args, **kwargs)
            after = time.perf_counter()

            logger.debug(" - DB call {} took {:.2f} ms".format(func.__name__, (after - before) * 1000))
            await stats.report_db_query(func.__name__, after - before, True)

            return res
        except asyncpg.exceptions.PostgresError:
            await stats.report_db_query(func.__name__, time.perf_counter() - before, False)
            logger.exception("Error from database query {}".format(func.__name__))
    return inner

@db_wrap
async def create_system(conn, system_name: str, system_hid: str):
    logger.debug("Creating system (name={}, hid={})".format(
        system_name, system_hid))
    return await conn.fetchrow("insert into systems (name, hid) values ($1, $2) returning *", system_name, system_hid)


@db_wrap
async def remove_system(conn, system_id: int):
    logger.debug("Deleting system (id={})".format(system_id))
    await conn.execute("delete from systems where id = $1", system_id)


@db_wrap
async def create_member(conn, system_id: int, member_name: str, member_hid: str):
    logger.debug("Creating member (system={}, name={}, hid={})".format(
        system_id, member_name, member_hid))
    return await conn.fetchrow("insert into members (name, system, hid) values ($1, $2, $3) returning *", member_name, system_id, member_hid)


@db_wrap
async def delete_member(conn, member_id: int):
    logger.debug("Deleting member (id={})".format(member_id))
    await conn.execute("delete from members where id = $1", member_id)


@db_wrap
async def link_account(conn, system_id: int, account_id: str):
    logger.debug("Linking account (account_id={}, system_id={})".format(
        account_id, system_id))
    await conn.execute("insert into accounts (uid, system) values ($1, $2)", int(account_id), system_id)


@db_wrap
async def unlink_account(conn, system_id: int, account_id: str):
    logger.debug("Unlinking account (account_id={}, system_id={})".format(
        account_id, system_id))
    await conn.execute("delete from accounts where uid = $1 and system = $2", int(account_id), system_id)


@db_wrap
async def get_linked_accounts(conn, system_id: int):
    return [row["uid"] for row in await conn.fetch("select uid from accounts where system = $1", system_id)]


@db_wrap
async def get_system_by_account(conn, account_id: str):
    return await conn.fetchrow("select systems.* from systems, accounts where accounts.uid = $1 and accounts.system = systems.id", int(account_id))


@db_wrap
async def get_system_by_hid(conn, system_hid: str):
    return await conn.fetchrow("select * from systems where hid = $1", system_hid)


@db_wrap
async def get_system(conn, system_id: int):
    return await conn.fetchrow("select * from systems where id = $1", system_id)


@db_wrap
async def get_member_by_name(conn, system_id: int, member_name: str):
    return await conn.fetchrow("select * from members where system = $1 and lower(name) = lower($2)", system_id, member_name)


@db_wrap
async def get_member_by_hid_in_system(conn, system_id: int, member_hid: str):
    return await conn.fetchrow("select * from members where system = $1 and hid = $2", system_id, member_hid)


@db_wrap
async def get_member_by_hid(conn, member_hid: str):
    return await conn.fetchrow("select * from members where hid = $1", member_hid)


@db_wrap
async def get_member(conn, member_id: int):
    return await conn.fetchrow("select * from members where id = $1", member_id)

@db_wrap
async def get_members(conn, members: list):
    return await conn.fetch("select * from members where id = any($1)", members)

@db_wrap
async def get_message(conn, message_id: str):
    return await conn.fetchrow("select * from messages where mid = $1", message_id)


@db_wrap
async def update_system_field(conn, system_id: int, field: str, value):
    logger.debug("Updating system field (id={}, {}={})".format(
        system_id, field, value))
    await conn.execute("update systems set {} = $1 where id = $2".format(field), value, system_id)


@db_wrap
async def update_member_field(conn, member_id: int, field: str, value):
    logger.debug("Updating member field (id={}, {}={})".format(
        member_id, field, value))
    await conn.execute("update members set {} = $1 where id = $2".format(field), value, member_id)


@db_wrap
async def get_all_members(conn, system_id: int):
    return await conn.fetch("select * from members where system = $1", system_id)


@db_wrap
async def get_members_exceeding(conn, system_id: int, length: int):
    return await conn.fetch("select * from members where system = $1 and length(name) > $2", system_id, length)


@db_wrap
async def get_webhook(conn, channel_id: str):
    return await conn.fetchrow("select webhook, token from webhooks where channel = $1", int(channel_id))


@db_wrap
async def add_webhook(conn, channel_id: str, webhook_id: str, webhook_token: str):
    logger.debug("Adding new webhook (channel={}, webhook={}, token={})".format(
        channel_id, webhook_id, webhook_token))
    await conn.execute("insert into webhooks (channel, webhook, token) values ($1, $2, $3)", int(channel_id), int(webhook_id), webhook_token)


@db_wrap
async def add_message(conn, message_id: str, channel_id: str, member_id: int, sender_id: str, content: str):
    logger.debug("Adding new message (id={}, channel={}, member={}, sender={})".format(
        message_id, channel_id, member_id, sender_id))
    await conn.execute("insert into messages (mid, channel, member, sender, content) values ($1, $2, $3, $4, $5)", int(message_id), int(channel_id), member_id, int(sender_id), content)


@db_wrap
async def get_members_by_account(conn, account_id: str):
    # Returns a "chimera" object
    return await conn.fetch("""select
            members.id, members.hid, members.prefix, members.suffix, members.color, members.name, members.avatar_url,
            systems.tag, systems.name as system_name, systems.hid as system_hid
        from
            systems, members, accounts
        where
            accounts.uid = $1
            and systems.id = accounts.system
            and members.system = systems.id""", int(account_id))


@db_wrap
async def get_message_by_sender_and_id(conn, message_id: str, sender_id: str):
    return await conn.fetchrow("""select
        messages.*,
        members.name, members.hid, members.avatar_url,
        systems.name as system_name, systems.hid as system_hid
    from
        messages, members, systems
    where
        messages.member = members.id
        and members.system = systems.id
        and mid = $1 and sender = $2""", int(message_id), int(sender_id))


@db_wrap
async def delete_message(conn, message_id: str):
    logger.debug("Deleting message (id={})".format(message_id))
    await conn.execute("delete from messages where mid = $1", int(message_id))

@db_wrap
async def front_history(conn, system_id: int, count: int):
    return await conn.fetch("""select
        switches.*,
        array(
            select member from switch_members
            where switch_members.switch = switches.id
            order by switch_members.id asc
        ) as members
    from switches
    where switches.system = $1
    order by switches.timestamp desc
    limit $2""", system_id, count)

@db_wrap
async def add_switch(conn, system_id: int):
    logger.debug("Adding switch (system={})".format(system_id))
    res = await conn.fetchrow("insert into switches (system) values ($1) returning *", system_id)
    return res["id"]

@db_wrap
async def move_last_switch(conn, system_id: int, switch_id: int, new_time):
    logger.debug("Moving latest switch (system={}, id={}, new_time={})".format(system_id, switch_id, new_time))
    await conn.execute("update switches set timestamp = $1 where system = $2 and id = $3", new_time, system_id, switch_id)

@db_wrap
async def add_switch_member(conn, switch_id: int, member_id: int):
    logger.debug("Adding switch member (switch={}, member={})".format(switch_id, member_id))
    await conn.execute("insert into switch_members (switch, member) values ($1, $2)", switch_id, member_id)

@db_wrap
async def get_server_info(conn, server_id: str):
    return await conn.fetchrow("select * from servers where id = $1", int(server_id))

@db_wrap
async def update_server(conn, server_id: str, logging_channel_id: str):
    logging_channel_id = int(logging_channel_id) if logging_channel_id else None
    logger.debug("Updating server settings (id={}, log_channel={})".format(server_id, logging_channel_id))
    await conn.execute("insert into servers (id, log_channel) values ($1, $2) on conflict (id) do update set log_channel = $2", int(server_id), logging_channel_id)

@db_wrap
async def member_count(conn):
    return await conn.fetchval("select count(*) from members")

@db_wrap
async def system_count(conn):
    return await conn.fetchval("select count(*) from systems")

async def create_tables(conn):
    await conn.execute("""create table if not exists systems (
        id          serial primary key,
        hid         char(5) unique not null,
        name        text,
        description text,
        tag         text,
        avatar_url  text,
        created     timestamp not null default current_timestamp
    )""")
    await conn.execute("""create table if not exists members (
        id          serial primary key,
        hid         char(5) unique not null,
        system      serial not null references systems(id) on delete cascade,
        color       char(6),
        avatar_url  text,
        name        text not null,
        birthday    date,
        pronouns    text,
        description text,
        prefix      text,
        suffix      text,
        created     timestamp not null default current_timestamp
    )""")
    await conn.execute("""create table if not exists accounts (
        uid         bigint primary key,
        system      serial not null references systems(id) on delete cascade
    )""")
    await conn.execute("""create table if not exists messages (
        mid         bigint primary key,
        channel     bigint not null,
        member      serial not null references members(id) on delete cascade,
        content     text not null,
        sender      bigint not null references accounts(uid)
    )""")
    await conn.execute("""create table if not exists switches (
        id          serial primary key,
        system      serial not null references systems(id) on delete cascade,
        timestamp   timestamp not null default current_timestamp
    )""")
    await conn.execute("""create table if not exists switch_members (
        id          serial primary key,
        switch      serial not null references switches(id) on delete cascade,
        member      serial not null references members(id) on delete cascade
    )""")
    await conn.execute("""create table if not exists webhooks (
        channel     bigint primary key,
        webhook     bigint not null,
        token       text not null
    )""")
    await conn.execute("""create table if not exists servers (
        id          bigint primary key,
        log_channel bigint
    )""")