////////////////////////////////////////////////////////////////
// Debugging

use super::*;
use routing_table::*;

fn get_bucket_entry_state(text: &str) -> Option<BucketEntryState> {
    if text == "dead" {
        Some(BucketEntryState::Dead)
    } else if text == "reliable" {
        Some(BucketEntryState::Reliable)
    } else if text == "unreliable" {
        Some(BucketEntryState::Unreliable)
    } else {
        None
    }
}
fn get_number(text: &str) -> Option<usize> {
    usize::from_str(text).ok()
}
fn get_dht_key(text: &str) -> Option<DHTKey> {
    DHTKey::try_decode(text).ok()
}
fn get_debug_argument<T, G: FnOnce(&str) -> Option<T>>(
    value: &str,
    context: &str,
    argument: &str,
    getter: G,
) -> Result<T, VeilidAPIError> {
    if let Some(val) = getter(value) {
        Ok(val)
    } else {
        Err(VeilidAPIError::InvalidArgument {
            context: context.to_owned(),
            argument: argument.to_owned(),
            value: value.to_owned(),
        })
    }
}
fn get_debug_argument_at<T, G: FnOnce(&str) -> Option<T>>(
    debug_args: &[String],
    pos: usize,
    context: &str,
    argument: &str,
    getter: G,
) -> Result<T, VeilidAPIError> {
    if pos >= debug_args.len() {
        return Err(VeilidAPIError::MissingArgument {
            context: context.to_owned(),
            argument: argument.to_owned(),
        });
    }
    let value = &debug_args[pos];
    if let Some(val) = getter(value) {
        Ok(val)
    } else {
        Err(VeilidAPIError::InvalidArgument {
            context: context.to_owned(),
            argument: argument.to_owned(),
            value: value.to_owned(),
        })
    }
}

impl VeilidAPI {
    async fn debug_buckets(&self, args: String) -> Result<String, VeilidAPIError> {
        let args: Vec<String> = args.split_whitespace().map(|s| s.to_owned()).collect();
        let mut min_state = BucketEntryState::Unreliable;
        if args.len() == 1 {
            min_state = get_debug_argument(
                &args[0],
                "debug_buckets",
                "min_state",
                get_bucket_entry_state,
            )?;
        }
        // Dump routing table bucket info
        let rpc = self.rpc_processor()?;
        let routing_table = rpc.routing_table();
        Ok(routing_table.debug_info_buckets(min_state))
    }

    async fn debug_dialinfo(&self, _args: String) -> Result<String, VeilidAPIError> {
        // Dump routing table dialinfo
        let rpc = self.rpc_processor()?;
        let routing_table = rpc.routing_table();
        Ok(routing_table.debug_info_dialinfo())
    }

    async fn debug_entries(&self, args: String) -> Result<String, VeilidAPIError> {
        let args: Vec<String> = args.split_whitespace().map(|s| s.to_owned()).collect();

        let mut min_state = BucketEntryState::Unreliable;
        let mut limit = 20;
        for arg in args {
            if let Some(ms) = get_bucket_entry_state(&arg) {
                min_state = ms;
            } else if let Some(lim) = get_number(&arg) {
                limit = lim;
            } else {
                return Err(VeilidAPIError::InvalidArgument {
                    context: "debug_entries".to_owned(),
                    argument: "unknown".to_owned(),
                    value: arg,
                });
            }
        }

        // Dump routing table entries
        let rpc = self.rpc_processor()?;
        let routing_table = rpc.routing_table();
        Ok(routing_table.debug_info_entries(limit, min_state))
    }

    async fn debug_entry(&self, args: String) -> Result<String, VeilidAPIError> {
        let args: Vec<String> = args.split_whitespace().map(|s| s.to_owned()).collect();

        let node_id = get_debug_argument_at(&args, 0, "debug_entry", "node_id", get_dht_key)?;

        // Dump routing table entry
        let rpc = self.rpc_processor()?;
        let routing_table = rpc.routing_table();
        Ok(routing_table.debug_info_entry(node_id))
    }

    async fn debug_nodeinfo(&self, _args: String) -> Result<String, VeilidAPIError> {
        // Dump routing table entry
        let rpc = self.rpc_processor()?;
        let routing_table = rpc.routing_table();
        Ok(routing_table.debug_info_nodeinfo())
    }

    async fn debug_config(&self, args: String) -> Result<String, VeilidAPIError> {
        let config = self.config()?;
        let args = args.trim_start();
        if args.is_empty() {
            return config
                .get_key_json("")
                .map_err(|e| VeilidAPIError::Internal { message: e });
        }
        let (arg, rest) = args.split_once(' ').unwrap_or((args, ""));
        let rest = rest.trim_start().to_owned();

        // Must be detached
        if matches!(
            self.get_state().await?.attachment,
            AttachmentState::Detached | AttachmentState::Detaching
        ) {
            return Err(VeilidAPIError::Internal {
                message: "Must be detached to change config".to_owned(),
            });
        }

        // One argument is 'config get'
        if rest.is_empty() {
            return config
                .get_key_json(arg)
                .map_err(|e| VeilidAPIError::Internal { message: e });
        }
        config
            .set_key_json(arg, &rest)
            .map_err(|e| VeilidAPIError::Internal { message: e })?;
        Ok("Config value set".to_owned())
    }

    async fn debug_purge(&self, args: String) -> Result<String, VeilidAPIError> {
        let args: Vec<String> = args.split_whitespace().map(|s| s.to_owned()).collect();
        if !args.is_empty() {
            if args[0] == "buckets" {
                // Must be detached
                if matches!(
                    self.get_state().await?.attachment,
                    AttachmentState::Detached | AttachmentState::Detaching
                ) {
                    return Err(VeilidAPIError::Internal {
                        message: "Must be detached to purge".to_owned(),
                    });
                }
                self.network_manager()?.routing_table().purge();
                Ok("Buckets purged".to_owned())
            } else {
                Err(VeilidAPIError::InvalidArgument {
                    context: "debug_purge".to_owned(),
                    argument: "parameter".to_owned(),
                    value: args[0].clone(),
                })
            }
        } else {
            Err(VeilidAPIError::MissingArgument {
                context: "debug_purge".to_owned(),
                argument: "parameter".to_owned(),
            })
        }
    }

    async fn debug_attach(&self, _args: String) -> Result<String, VeilidAPIError> {
        if !matches!(
            self.get_state().await?.attachment,
            AttachmentState::Detached
        ) {
            return Err(VeilidAPIError::Internal {
                message: "Not detached".to_owned(),
            });
        };

        self.attach().await?;

        Ok("Attached".to_owned())
    }

    async fn debug_detach(&self, _args: String) -> Result<String, VeilidAPIError> {
        if matches!(
            self.get_state().await?.attachment,
            AttachmentState::Detaching
        ) {
            return Err(VeilidAPIError::Internal {
                message: "Not attached".to_owned(),
            });
        };

        self.detach().await?;

        Ok("Detached".to_owned())
    }

    pub async fn debug_help(&self, _args: String) -> Result<String, VeilidAPIError> {
        Ok(r#">>> Debug commands:
        buckets [dead|reliable]
        dialinfo
        entries [dead|reliable] [limit]
        entry [node_id]
        nodeinfo
        config [key [new value]]
        purge buckets
        attach
        detach
    "#
        .to_owned())
    }

    pub async fn debug(&self, args: String) -> Result<String, VeilidAPIError> {
        let args = args.trim_start();
        if args.is_empty() {
            // No arguments runs help command
            return self.debug_help("".to_owned()).await;
        }
        let (arg, rest) = args.split_once(' ').unwrap_or((args, ""));
        let rest = rest.trim_start().to_owned();

        let mut out = String::new();
        if arg == "buckets" {
            out += self.debug_buckets(rest).await?.as_str();
        } else if arg == "dialinfo" {
            out += self.debug_dialinfo(rest).await?.as_str();
        } else if arg == "entries" {
            out += self.debug_entries(rest).await?.as_str();
        } else if arg == "entry" {
            out += self.debug_entry(rest).await?.as_str();
        } else if arg == "nodeinfo" {
            out += self.debug_nodeinfo(rest).await?.as_str();
        } else if arg == "purge" {
            out += self.debug_purge(rest).await?.as_str();
        } else if arg == "attach" {
            out += self.debug_attach(rest).await?.as_str();
        } else if arg == "detach" {
            out += self.debug_detach(rest).await?.as_str();
        } else if arg == "config" {
            out += self.debug_config(rest).await?.as_str();
        } else {
            out += ">>> Unknown command\n";
        }
        Ok(out)
    }
}