#![allow(dead_code)]
use crate::grpc::brain as grpc;
use dashmap::DashMap;
use log::{debug, info, warn};
use std::sync::RwLock;
use tokio::sync::mpsc::Sender;
use tokio::sync::oneshot::Sender as OneshotSender;

#[derive(Eq, Hash, PartialEq, Clone)]
pub struct Node {
    pub public_key: String,
    pub owner_key: String,
    pub country: 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,
}

impl From<grpc::RegisterNodeRequest> for Node {
    fn from(node: grpc::RegisterNodeRequest) -> Self {
        Node {
            public_key: node.node_pubkey,
            owner_key: node.owner_pubkey,
            country: node.country,
            city: node.city,
            ip: node.ip,
            avail_mem_mb: node.avail_memory_mb,
            avail_vcpus: node.avail_vcpus,
            avail_storage_gbs: node.avail_storage_gb,
            avail_ipv4: node.avail_ipv4,
            avail_ipv6: node.avail_ipv6,
            avail_ports: node.avail_ports,
            max_ports_per_vm: node.max_ports_per_vm,
        }
    }
}

impl Into<grpc::NodeListResp> for Node {
    fn into(self) -> grpc::NodeListResp {
        grpc::NodeListResp {
            node_pubkey: self.public_key,
            country: self.country,
            city: self.city,
            ip: self.ip,
            server_rating: 0,
            provider_rating: 0,
        }
    }
}

#[derive(Clone, Debug)]
pub struct Contract {
    pub uuid: String,
    pub hostname: String,
    pub admin_pubkey: String,
    pub node_pubkey: String,
    pub exposed_ports: Vec<u32>,
    pub public_ipv4: String,
    pub public_ipv6: String,
    pub disk_size_gb: u32,
    pub vcpus: u32,
    pub memory_mb: u32,
    pub kernel_sha: String,
    pub dtrfs_sha: String,
    pub created_at: String,
}

impl Into<grpc::VmContract> for Contract {
    fn into(self) -> grpc::VmContract {
        grpc::VmContract {
            uuid: self.uuid,
            hostname: self.hostname,
            admin_pubkey: self.admin_pubkey,
            node_pubkey: self.node_pubkey,
            exposed_ports: self.exposed_ports,
            public_ipv4: self.public_ipv4,
            public_ipv6: self.public_ipv6,
            disk_size_gb: self.disk_size_gb,
            vcpus: self.vcpus,
            memory_mb: self.memory_mb,
            kernel_sha: self.kernel_sha,
            dtrfs_sha: self.dtrfs_sha,
            created_at: self.created_at,
        }
    }
}

#[derive(Default)]
pub struct BrainData {
    nodes: RwLock<Vec<Node>>,
    contracts: RwLock<Vec<Contract>>,
    tmp_vmrequests: DashMap<String, (grpc::NewVmRequest, OneshotSender<grpc::NewVmConfirmation>)>,
    tmp_updatevmrequests: DashMap<String, (grpc::UpdateVmRequest, OneshotSender<grpc::UpdateVmResp>)>,
    daemon_deletevm_tx: DashMap<String, Sender<grpc::DeletedVmUpdate>>,
    daemon_newvm_tx: DashMap<String, Sender<grpc::NewVmRequest>>,
    daemon_updatevm_tx: DashMap<String, Sender<grpc::UpdateVmRequest>>,
}

#[derive(Debug)]
enum TxType {
    CliContract,
    DaemonDeleteVm,
    DaemonNewVm,
}

impl BrainData {
    pub fn new() -> Self {
        Self {
            nodes: RwLock::new(Vec::new()),
            contracts: RwLock::new(Vec::new()),
            tmp_vmrequests: DashMap::new(),
            tmp_updatevmrequests: DashMap::new(),
            daemon_deletevm_tx: DashMap::new(),
            daemon_newvm_tx: DashMap::new(),
            daemon_updatevm_tx: DashMap::new(),
        }
    }

    pub fn insert_node(&self, node: grpc::RegisterNodeRequest) {
        info!("Registering node {node:?}");
        let mut nodes = self.nodes.write().unwrap();
        for n in nodes.iter_mut() {
            if n.public_key == node.node_pubkey {
                info!("Node {} already exists. Updating data.", n.public_key);
                *n = node.into();
                return;
            }
        }
        nodes.push(node.into());
    }

    pub fn add_daemon_deletevm_tx(&self, node_pubkey: &str, tx: Sender<grpc::DeletedVmUpdate>) {
        self.daemon_deletevm_tx.insert(node_pubkey.to_string(), tx);
    }

    pub async fn add_daemon_updatevm_tx(&self, node_pubkey: &str, tx: Sender<grpc::UpdateVmRequest>) {
        log::debug!("Adding daemon updatevm tx for node_pubkey: {}", node_pubkey);
        self.tmp_updatevmrequests
            .retain(|_, req| req.0.node_pubkey != node_pubkey);
        self.daemon_updatevm_tx.insert(node_pubkey.to_string(), tx);
    }

    pub async fn delete_vm(&self, delete_vm: grpc::DeletedVmUpdate) {
        if let Some(contract) = self.find_contract_by_uuid(&delete_vm.uuid) {
            info!("Found vm {}. Deleting...", delete_vm.uuid);
            if let Some(daemon_tx) = self.daemon_deletevm_tx.get(&contract.node_pubkey) {
                debug!(
                    "TX for daemon {} found. Informing daemon about deletion of {}.",
                    contract.node_pubkey, delete_vm.uuid
                );
                if daemon_tx.send(delete_vm.clone()).await.is_err() {
                    warn!(
                        "Failed to send deletion request to {}. Triggering memory cleanup.",
                        contract.node_pubkey
                    );
                }
            }
            let mut contracts = self.contracts.write().unwrap();
            contracts.retain(|c| c.uuid != delete_vm.uuid);
        }
    }

    pub async fn add_daemon_newvm_tx(&self, node_pubkey: &str, tx: Sender<grpc::NewVmRequest>) {
        self.tmp_vmrequests
            .retain(|_, req| req.0.node_pubkey != node_pubkey);
        self.daemon_newvm_tx.insert(node_pubkey.to_string(), tx);
    }

    pub async fn submit_vmconfirmation(&self, confirmation: grpc::NewVmConfirmation) {
        let newvmreq = match self.tmp_vmrequests.remove(&confirmation.uuid) {
            Some((_, r)) => r,
            None => {
                log::error!(
                    "Received confirmation for ghost NewVMReq {}",
                    confirmation.uuid
                );
                return;
            }
        };
        if let Err(e) = newvmreq.1.send(confirmation.clone()) {
            log::error!(
                "CLI RX for {} dropped before receiving confirmation {:?}. Error is: {:?}",
                &newvmreq.0.admin_pubkey,
                confirmation,
                e
            );
        }
        if confirmation.error != "" {
            return;
        }
        let contract = Contract {
            uuid: confirmation.uuid,
            exposed_ports: confirmation.exposed_ports,
            public_ipv4: confirmation.public_ipv4,
            public_ipv6: confirmation.public_ipv6,
            created_at: format!("{:?}", std::time::SystemTime::now()),
            hostname: newvmreq.0.hostname,
            admin_pubkey: newvmreq.0.admin_pubkey,
            node_pubkey: newvmreq.0.node_pubkey,
            disk_size_gb: newvmreq.0.disk_size_gb,
            vcpus: newvmreq.0.vcpus,
            memory_mb: newvmreq.0.memory_mb,
            kernel_sha: newvmreq.0.kernel_sha,
            dtrfs_sha: newvmreq.0.dtrfs_sha,
        };
        info!("Created new contract: {contract:?}");
        self.contracts.write().unwrap().push(contract);
    }

    pub async fn submit_update_vmconfirmation(&self, confirmation: grpc::UpdateVmResp) {
        let updatevmreq = match self.tmp_updatevmrequests.remove(&confirmation.uuid) {
            Some((_, r)) => r,
            None => {
                log::error!(
                    "Received confirmation for ghost UpdateVMRequest {}",
                    confirmation.uuid
                );
                return;
            }
        };
        if let Err(e) = updatevmreq.1.send(confirmation.clone()) {
            log::error!(
                "CLI RX for {} dropped before receiving confirmation {:?}. Error is: {:?}",
                &updatevmreq.0.node_pubkey,
                confirmation,
                e
            );
        }
        if confirmation.error != "" {
            return;
        }
        let mut contracts = self.contracts.write().unwrap();
        if let Some(contract) = contracts.iter_mut().find(|c| c.uuid == confirmation.uuid) {
            contract.disk_size_gb = updatevmreq.0.disk_size_gb;
            contract.vcpus = updatevmreq.0.vcpus;
            contract.memory_mb = updatevmreq.0.memory_mb;
            contract.kernel_sha = updatevmreq.0.kernel_sha;
            contract.dtrfs_sha = updatevmreq.0.dtrfs_sha;
        }
    }

    pub async fn submit_newvmrequest(
        &self,
        mut req: grpc::NewVmRequest,
        tx: OneshotSender<grpc::NewVmConfirmation>,
    ) {
        let uuid = uuid::Uuid::new_v4().to_string();

        req.uuid = uuid.clone();
        info!("Inserting new vm request in memory: {req:?}");
        self.tmp_vmrequests
            .insert(req.uuid.clone(), (req.clone(), tx));
        if let Some(server_tx) = self.daemon_newvm_tx.get(&req.node_pubkey) {
            debug!(
                "Found daemon TX for {}. Sending newVMReq {}",
                req.node_pubkey, req.uuid
            );
            if server_tx.send(req.clone()).await.is_ok() {
                return;
            } else {
                warn!(
                    "Daemon {} RX dropped before sending update. Cleaning memory...",
                    req.node_pubkey
                );
                self.submit_vmconfirmation(grpc::NewVmConfirmation {
                    error: "Daemon is offline.".to_string(),
                    uuid,
                    exposed_ports: Vec::new(),
                    public_ipv4: "".to_string(),
                    public_ipv6: "".to_string(),
                })
                .await;
            }
        }
    }

    pub async fn submit_updatevmrequest(
        &self,
        req: grpc::UpdateVmRequest,
        tx: OneshotSender<grpc::UpdateVmResp>,
    ) {
        let uuid = req.uuid.clone();
        info!("Inserting new vm update request in memory: {req:?}");
        self.tmp_updatevmrequests
            .insert(req.uuid.clone(), (req.clone(), tx));
        if let Some(server_tx) = self.daemon_updatevm_tx.get(&req.node_pubkey) {
            debug!(
                "Found daemon TX for {}. Sending updateVMReq {}",
                req.node_pubkey, req.uuid
            );
            if server_tx.send(req.clone()).await.is_ok() {
                return;
            } else {
                warn!(
                    "Daemon {} RX dropped before sending update. Cleaning memory...",
                    req.node_pubkey
                );
                self.submit_update_vmconfirmation(grpc::UpdateVmResp {
                    uuid,
                    timestamp: chrono::Utc::now().to_rfc3339(),
                    error: "Daemon is offline.".to_string(),
                })
                .await;
            }
        }
    }

    pub fn insert_contract(&self, contract: Contract) {
        let mut contracts = self.contracts.write().unwrap();
        contracts.push(contract);
    }

    pub fn find_nodes_by_pubkey(&self, public_key: &str) -> Option<Node> {
        let nodes = self.nodes.read().unwrap();
        nodes.iter().cloned().find(|n| n.public_key == public_key)
    }

    pub fn find_ns_by_owner_key(&self, owner_key: &str) -> Option<Node> {
        let nodes = self.nodes.read().unwrap();
        nodes.iter().cloned().find(|n| n.owner_key == owner_key)
    }

    pub fn find_nodes_by_filters(&self, filters: &crate::grpc::brain::NodeFilters) -> Vec<Node> {
        let nodes = self.nodes.read().unwrap();
        nodes
            .iter()
            .cloned()
            .filter(|n| {
                n.avail_ports >= filters.free_ports
                    && (!filters.offers_ipv4 || n.avail_ipv4 > 0)
                    && (!filters.offers_ipv6 || n.avail_ipv6 > 0)
                    && n.avail_vcpus >= filters.vcpus
                    && n.avail_mem_mb >= filters.memory_mb
                    && n.avail_storage_gbs >= filters.storage_gb
            })
            .collect()
    }

    pub fn find_contract_by_uuid(&self, uuid: &str) -> Option<Contract> {
        let contracts = self.contracts.read().unwrap();
        contracts.iter().cloned().find(|c| c.uuid == uuid)
    }

    pub fn find_contracts_by_admin_pubkey(&self, admin_pubkey: &str) -> Vec<Contract> {
        debug!("Searching contracts for admin pubkey {admin_pubkey}");
        let contracts: Vec<Contract> = self
            .contracts
            .read()
            .unwrap()
            .iter()
            .cloned()
            .filter(|c| c.admin_pubkey == admin_pubkey)
            .collect();
        debug!("Found {} contracts or {admin_pubkey}.", contracts.len());
        contracts
    }

    pub fn find_contracts_by_node_pubkey(&self, node_pubkey: &str) -> Vec<Contract> {
        let contracts = self.contracts.read().unwrap();
        contracts
            .iter()
            .cloned()
            .filter(|c| c.node_pubkey == node_pubkey)
            .collect()
    }
}