use std::str::FromStr;
use std::time::Duration;

use super::Error;
use crate::constants::{ACCOUNT, ACTIVE_VM, DELETED_VM, NEW_VM_REQ, VM_NODE};
use crate::db::general::Report;
use crate::old_brain;
use serde::{Deserialize, Serialize};
use surrealdb::engine::remote::ws::Client;
use surrealdb::sql::Datetime;
use surrealdb::{Notification, RecordId, Surreal};
use tokio_stream::StreamExt as _;

#[derive(Debug, Serialize, Deserialize)]
pub struct VmNode {
    pub id: RecordId,
    pub operator: RecordId,
    pub country: String,
    pub region: String,
    pub city: String,
    pub ip: String,
    pub avail_mem_mb: u32,
    pub avail_vcpus: u32,
    pub avail_storage_gbs: u32,
    pub avail_ipv4: u32,
    pub avail_ipv6: u32,
    pub avail_ports: u32,
    pub max_ports_per_vm: u32,
    pub price: u64,
    pub offline_minutes: u64,
}

#[derive(Serialize)]
pub struct VmNodeResources {
    pub avail_mem_mb: u32,
    pub avail_vcpus: u32,
    pub avail_storage_gbs: u32,
    pub avail_ipv4: u32,
    pub avail_ipv6: u32,
    pub avail_ports: u32,
    pub max_ports_per_vm: u32,
}

impl VmNodeResources {
    pub async fn merge(self, db: &Surreal<Client>, node_id: &str) -> Result<(), Error> {
        let _: Option<VmNode> = db.update((VM_NODE, node_id)).merge(self).await?;
        Ok(())
    }
}

impl VmNode {
    pub async fn register(self, db: &Surreal<Client>) -> Result<(), Error> {
        let _: Option<VmNode> = db.upsert(self.id.clone()).content(self).await?;
        Ok(())
    }
}

#[derive(Debug, Serialize, Deserialize)]
pub struct VmNodeWithReports {
    pub id: RecordId,
    pub operator: RecordId,
    pub country: String,
    pub region: String,
    pub city: String,
    pub ip: String,
    pub avail_mem_mb: u32,
    pub avail_vcpus: u32,
    pub avail_storage_gbs: u32,
    pub avail_ipv4: u32,
    pub avail_ipv6: u32,
    pub avail_ports: u32,
    pub max_ports_per_vm: u32,
    pub price: u64,
    pub offline_minutes: u64,
    pub reports: Vec<Report>,
}

impl VmNodeWithReports {
    // TODO: find a more elegant way to do this than importing gRPC in the DB module
    // https://en.wikipedia.org/wiki/Dependency_inversion_principle
    pub async fn find_by_filters(
        db: &Surreal<Client>,
        filters: detee_shared::snp::pb::vm_proto::VmNodeFilters,
    ) -> Result<Vec<Self>, Error> {
        let mut query = format!(
            "select *, <-report.* as reports from {VM_NODE} where
            avail_ports >= {} &&
            max_ports_per_vm >= {} &&
            avail_ipv4 >= {} &&
            avail_ipv6 >= {} &&
            avail_vcpus >= {} &&
            avail_mem_mb >= {} &&
            avail_storage_gbs >= {}\n",
            filters.free_ports,
            filters.free_ports,
            filters.offers_ipv4 as u32,
            filters.offers_ipv6 as u32,
            filters.vcpus,
            filters.memory_mb,
            filters.storage_gb
        );
        if !filters.city.is_empty() {
            query += &format!("&& city = '{}' ", filters.city);
        }
        if !filters.region.is_empty() {
            query += &format!("&& region = '{}' ", filters.region);
        }
        if !filters.country.is_empty() {
            query += &format!("&& country = '{}' ", filters.country);
        }
        if !filters.ip.is_empty() {
            query += &format!("&& ip = '{}' ", filters.ip);
        }
        query += ";";
        let mut result = db.query(query).await?;
        let vm_nodes: Vec<Self> = result.take(0)?;
        Ok(vm_nodes)
    }
}

pub enum VmDaemonNotification {
    Create(NewVmReq),
    Update(UpdateVmReq),
    Delete(DeletedVm),
}

impl From<NewVmReq> for VmDaemonNotification {
    fn from(value: NewVmReq) -> Self {
        Self::Create(value)
    }
}

impl From<UpdateVmReq> for VmDaemonNotification {
    fn from(value: UpdateVmReq) -> Self {
        Self::Update(value)
    }
}

impl From<DeletedVm> for VmDaemonNotification {
    fn from(value: DeletedVm) -> Self {
        Self::Delete(value)
    }
}

#[derive(Debug, Serialize, Deserialize)]
pub struct NewVmReq {
    pub id: RecordId,
    #[serde(rename = "in")]
    pub admin: RecordId,
    #[serde(rename = "out")]
    pub vm_node: RecordId,
    pub hostname: String,
    pub extra_ports: Vec<u32>,
    pub public_ipv4: bool,
    pub public_ipv6: bool,
    pub disk_size_gb: u32,
    pub vcpus: u32,
    pub memory_mb: u32,
    pub dtrfs_url: String,
    pub dtrfs_sha: String,
    pub kernel_sha: String,
    pub kernel_url: String,
    pub created_at: Datetime,
    pub price_per_unit: u64,
    pub locked_nano: u64,
    pub error: String,
}

impl NewVmReq {
    pub async fn get(db: &Surreal<Client>, id: &str) -> Result<Option<Self>, Error> {
        let new_vm_req: Option<Self> = db.select((NEW_VM_REQ, id)).await?;
        Ok(new_vm_req)
    }

    pub async fn delete(db: &Surreal<Client>, id: &str) -> Result<(), Error> {
        let _: Option<Self> = db.delete((NEW_VM_REQ, id)).await?;
        Ok(())
    }

    pub async fn submit_error(db: &Surreal<Client>, id: &str, error: String) -> Result<(), Error> {
        #[derive(Serialize)]
        struct NewVmError {
            error: String,
        }
        let _: Option<Self> = db.update((NEW_VM_REQ, id)).merge(NewVmError { error }).await?;
        Ok(())
    }

    pub async fn submit(self, db: &Surreal<Client>) -> Result<(), Error> {
        let _: Vec<Self> = db.insert(NEW_VM_REQ).relation(self).await?;
        Ok(())
    }
}

/// first string is the vm_id
pub enum NewVmResp {
    // TODO: find a more elegant way to do this than importing gRPC in the DB module
    // https://en.wikipedia.org/wiki/Dependency_inversion_principle
    Args(String, detee_shared::snp::pb::vm_proto::MeasurementArgs),
    Error(String, String),
}

impl NewVmResp {
    pub async fn listen(db: &Surreal<Client>, vm_id: &str) -> Result<NewVmResp, Error> {
        let mut resp = db
            .query(format!("live select * from {NEW_VM_REQ} where id = {NEW_VM_REQ}:{vm_id};"))
            .query(format!(
                "live select * from measurement_args where id = measurement_args:{vm_id};"
            ))
            .await?;
        let mut new_vm_stream = resp.stream::<Notification<NewVmReq>>(0)?;
        let mut args_stream =
            resp.stream::<Notification<detee_shared::snp::pb::vm_proto::MeasurementArgs>>(1)?;

        tokio::time::timeout(Duration::from_secs(10), async {
            loop {
                tokio::select! {
                    new_vm_req_notif = new_vm_stream.next() => {
                        log::debug!("Got stream 1...");
                        if let Some(new_vm_req_notif) = new_vm_req_notif {
                            match new_vm_req_notif {
                                Ok(new_vm_req_notif) => {
                                    if new_vm_req_notif.action == surrealdb::Action::Update && !new_vm_req_notif.data.error.is_empty() {
                                        return Ok::<NewVmResp, Error>(Self::Error(vm_id.to_string(), new_vm_req_notif.data.error));
                                    };
                                },
                                Err(e) => return Err(e.into()),
                            }
                        }
                    }
                    args_notif = args_stream.next() => {
                        if let Some(args_notif) = args_notif {
                            match args_notif {
                                Ok(args_notif) => {
                                    if args_notif.action == surrealdb::Action::Create {
                                        return Ok(Self::Args(vm_id.to_string(), args_notif.data));
                                    };
                                },
                                Err(e) => return Err(e.into()),
                            }
                        }
                    }
                }
            }
        }).await?
    }
}

#[derive(Debug, Serialize, Deserialize)]
pub struct ActiveVm {
    pub id: RecordId,
    #[serde(rename = "in")]
    pub admin: RecordId,
    #[serde(rename = "out")]
    pub vm_node: RecordId,
    pub hostname: String,
    pub mapped_ports: Vec<(u32, u32)>,
    pub public_ipv4: String,
    pub public_ipv6: String,
    pub disk_size_gb: u32,
    pub vcpus: u32,
    pub memory_mb: u32,
    pub dtrfs_sha: String,
    pub kernel_sha: String,
    pub created_at: Datetime,
    pub price_per_unit: u64,
    pub locked_nano: u64,
    pub collected_at: Datetime,
}

impl ActiveVm {
    pub async fn activate(
        db: &Surreal<Client>,
        id: &str,
        args: detee_shared::vm_proto::MeasurementArgs,
    ) -> Result<(), Error> {
        let new_vm_req = match NewVmReq::get(db, id).await? {
            Some(r) => r,
            None => return Ok(()),
        };

        let mut public_ipv4 = String::new();
        let mut public_ipv6 = String::new();

        for ip in args.ips.iter() {
            if let Ok(ipv4_addr) = std::net::Ipv4Addr::from_str(&ip.address) {
                if !ipv4_addr.is_private() && !ipv4_addr.is_link_local() {
                    public_ipv4 = ipv4_addr.to_string();
                }
                continue;
            }
            if let Ok(ipv6_addr) = std::net::Ipv6Addr::from_str(&ip.address) {
                public_ipv6 = ipv6_addr.to_string();
            }
        }

        let mut mapped_ports = Vec::new();
        let mut guest_ports = vec![22];
        guest_ports.append(&mut args.exposed_ports.clone());
        let mut i = 0;
        while i < new_vm_req.extra_ports.len() && i < guest_ports.len() {
            mapped_ports.push((args.exposed_ports[i], guest_ports[i]));
            i += 1;
        }

        let active_vm = ActiveVm {
            id: RecordId::from((ACTIVE_VM, id)),
            admin: new_vm_req.admin,
            vm_node: new_vm_req.vm_node,
            hostname: new_vm_req.hostname,
            mapped_ports,
            public_ipv4,
            public_ipv6,
            disk_size_gb: new_vm_req.disk_size_gb,
            vcpus: new_vm_req.vcpus,
            memory_mb: new_vm_req.memory_mb,
            dtrfs_sha: new_vm_req.dtrfs_sha,
            kernel_sha: new_vm_req.kernel_sha,
            created_at: new_vm_req.created_at.clone(),
            price_per_unit: new_vm_req.price_per_unit,
            locked_nano: new_vm_req.locked_nano,
            collected_at: new_vm_req.created_at,
        };

        let _: Vec<ActiveVm> = db.insert(()).relation(active_vm).await?;

        NewVmReq::delete(db, id).await?;
        Ok(())
    }
}

#[derive(Debug, Serialize, Deserialize)]
pub struct UpdateVmReq {
    pub id: RecordId,
    #[serde(rename = "in")]
    pub admin: RecordId,
    #[serde(rename = "out")]
    pub vm_node: RecordId,
    pub disk_size_gb: u32,
    pub vcpus: u32,
    pub memory_mb: u32,
    pub dtrfs_url: String,
    pub dtrfs_sha: String,
    pub kernel_sha: String,
    pub kernel_url: String,
    pub created_at: Datetime,
    pub price_per_unit: u64,
    pub locked_nano: u64,
}

#[derive(Debug, Serialize, Deserialize)]
pub struct DeletedVm {
    pub id: RecordId,
    #[serde(rename = "in")]
    pub admin: RecordId,
    #[serde(rename = "out")]
    pub vm_node: RecordId,
    pub hostname: String,
    pub mapped_ports: Vec<(u32, u32)>,
    pub public_ipv4: String,
    pub public_ipv6: String,
    pub disk_size_gb: u32,
    pub vcpus: u32,
    pub memory_mb: u32,
    pub dtrfs_sha: String,
    pub kernel_sha: String,
    pub created_at: Datetime,
    pub deleted_at: Datetime,
    pub price_per_unit: u64,
}

impl DeletedVm {
    pub async fn get_by_uuid(db: &Surreal<Client>, uuid: &str) -> Result<Option<Self>, Error> {
        let contract: Option<Self> =
            db.query(format!("select * from {DELETED_VM}:{uuid};")).await?.take(0)?;
        Ok(contract)
    }

    pub async fn list_by_admin(db: &Surreal<Client>, admin: &str) -> Result<Vec<Self>, Error> {
        let mut result =
            db.query(format!("select * from {DELETED_VM} where in = {ACCOUNT}:{admin};")).await?;
        let contracts: Vec<Self> = result.take(0)?;
        Ok(contracts)
    }

    pub async fn list_by_node(db: &Surreal<Client>, admin: &str) -> Result<Vec<Self>, Error> {
        let mut result =
            db.query(format!("select * from {DELETED_VM} where out = {VM_NODE}:{admin};")).await?;
        let contracts: Vec<Self> = result.take(0)?;
        Ok(contracts)
    }

    pub async fn list_by_operator(
        db: &Surreal<Client>,
        operator: &str,
    ) -> Result<Vec<Self>, Error> {
        let mut result = db
            .query(format!(
                "select
                (select * from ->operator->vm_node<-{DELETED_VM}) as contracts
            from {ACCOUNT}:{operator};"
            ))
            .await?;

        #[derive(Deserialize)]
        struct Wrapper {
            contracts: Vec<DeletedVm>,
        }

        let c: Option<Wrapper> = result.take(0)?;
        match c {
            Some(c) => Ok(c.contracts),
            None => Ok(Vec::new()),
        }
    }

    /// total hardware units of this VM
    fn total_units(&self) -> u64 {
        // TODO: Optimize this based on price of hardware.
        // I tried, but this can be done better.
        // Storage cost should also be based on tier
        (self.vcpus as u64 * 10)
            + ((self.memory_mb + 256) as u64 / 200)
            + (self.disk_size_gb as u64 / 10)
            + (!self.public_ipv4.is_empty() as u64 * 10)
    }

    /// Returns price per minute in nanoLP
    pub fn price_per_minute(&self) -> u64 {
        self.total_units() * self.price_per_unit
    }
}

impl ActiveVm {
    /// total hardware units of this VM
    fn total_units(&self) -> u64 {
        // TODO: Optimize this based on price of hardware.
        // I tried, but this can be done better.
        // Storage cost should also be based on tier
        (self.vcpus as u64 * 10)
            + ((self.memory_mb + 256) as u64 / 200)
            + (self.disk_size_gb as u64 / 10)
            + (!self.public_ipv4.is_empty() as u64 * 10)
    }

    /// Returns price per minute in nanoLP
    pub fn price_per_minute(&self) -> u64 {
        self.total_units() * self.price_per_unit
    }
}

#[derive(Debug, Serialize, Deserialize)]
pub struct ActiveVmWithNode {
    pub id: RecordId,
    #[serde(rename = "in")]
    pub admin: RecordId,
    #[serde(rename = "out")]
    pub vm_node: VmNode,
    pub hostname: String,
    pub mapped_ports: Vec<(u32, u32)>,
    pub public_ipv4: String,
    pub public_ipv6: String,
    pub disk_size_gb: u32,
    pub vcpus: u32,
    pub memory_mb: u32,
    pub dtrfs_sha: String,
    pub kernel_sha: String,
    pub created_at: Datetime,
    pub price_per_unit: u64,
    pub locked_nano: u64,
    pub collected_at: Datetime,
}

impl ActiveVmWithNode {
    pub async fn get_by_uuid(db: &Surreal<Client>, uuid: &str) -> Result<Option<Self>, Error> {
        let contract: Option<Self> =
            db.query(format!("select * from {ACTIVE_VM}:{uuid} fetch out;")).await?.take(0)?;
        Ok(contract)
    }

    pub async fn list_by_admin(db: &Surreal<Client>, admin: &str) -> Result<Vec<Self>, Error> {
        let mut result = db
            .query(format!("select * from {ACTIVE_VM} where in = {ACCOUNT}:{admin} fetch out;"))
            .await?;
        let contracts: Vec<Self> = result.take(0)?;
        Ok(contracts)
    }

    pub async fn list_by_node(db: &Surreal<Client>, admin: &str) -> Result<Vec<Self>, Error> {
        let mut result = db
            .query(format!("select * from {ACTIVE_VM} where out = {VM_NODE}:{admin} fetch out;"))
            .await?;
        let contracts: Vec<Self> = result.take(0)?;
        Ok(contracts)
    }

    pub async fn list_by_operator(
        db: &Surreal<Client>,
        operator: &str,
    ) -> Result<Vec<Self>, Error> {
        let mut result = db
            .query(format!(
                "select
                (select * from ->operator->vm_node<-{ACTIVE_VM} fetch out) as contracts
            from {ACCOUNT}:{operator};"
            ))
            .await?;

        #[derive(Deserialize)]
        struct Wrapper {
            contracts: Vec<ActiveVmWithNode>,
        }

        let c: Option<Wrapper> = result.take(0)?;
        match c {
            Some(c) => Ok(c.contracts),
            None => Ok(Vec::new()),
        }
    }

    /// total hardware units of this VM
    fn total_units(&self) -> u64 {
        // TODO: Optimize this based on price of hardware.
        // I tried, but this can be done better.
        // Storage cost should also be based on tier
        (self.vcpus as u64 * 10)
            + ((self.memory_mb + 256) as u64 / 200)
            + (self.disk_size_gb as u64 / 10)
            + (!self.public_ipv4.is_empty() as u64 * 10)
    }

    /// Returns price per minute in nanoLP
    pub fn price_per_minute(&self) -> u64 {
        self.total_units() * self.price_per_unit
    }
}

// TODO: delete all of these From implementation after migration 0 gets executed

impl From<&old_brain::BrainData> for Vec<VmNode> {
    fn from(old_data: &old_brain::BrainData) -> Self {
        let mut nodes = Vec::new();
        for old_node in old_data.vm_nodes.iter() {
            nodes.push(VmNode {
                id: RecordId::from((VM_NODE, old_node.public_key.clone())),
                operator: RecordId::from((ACCOUNT, old_node.operator_wallet.clone())),
                country: old_node.country.clone(),
                region: old_node.region.clone(),
                city: old_node.city.clone(),
                ip: old_node.ip.clone(),
                avail_mem_mb: old_node.avail_mem_mb,
                avail_vcpus: old_node.avail_vcpus,
                avail_storage_gbs: old_node.avail_storage_gbs,
                avail_ipv4: old_node.avail_ipv4,
                avail_ipv6: old_node.avail_ipv6,
                avail_ports: old_node.avail_ports,
                max_ports_per_vm: old_node.max_ports_per_vm,
                price: old_node.price,
                offline_minutes: old_node.offline_minutes,
            });
        }
        nodes
    }
}

impl From<&old_brain::BrainData> for Vec<ActiveVm> {
    fn from(old_data: &old_brain::BrainData) -> Self {
        let mut contracts = Vec::new();
        for old_c in old_data.vm_contracts.iter() {
            let mut mapped_ports = Vec::new();
            for port in old_c.exposed_ports.iter() {
                mapped_ports.push((*port, 8080u32));
            }
            contracts.push(ActiveVm {
                id: RecordId::from((ACTIVE_VM, old_c.uuid.replace("-", ""))),
                admin: RecordId::from((ACCOUNT, old_c.admin_pubkey.clone())),
                vm_node: RecordId::from((VM_NODE, old_c.node_pubkey.clone())),
                hostname: old_c.hostname.clone(),
                mapped_ports,
                public_ipv4: old_c.public_ipv4.clone(),
                public_ipv6: old_c.public_ipv6.clone(),
                disk_size_gb: old_c.disk_size_gb,
                vcpus: old_c.vcpus,
                memory_mb: old_c.memory_mb,
                dtrfs_sha: old_c.dtrfs_sha.clone(),
                kernel_sha: old_c.kernel_sha.clone(),
                price_per_unit: old_c.price_per_unit,
                locked_nano: old_c.locked_nano,
                created_at: old_c.created_at.into(),
                collected_at: old_c.collected_at.into(),
            });
        }
        contracts
    }
}