use std::collections::HashMap;

use anyhow::{anyhow, Result};
use serde::{Deserialize, Serialize};

use crate::config::RuntimeConfigConsul;

#[derive(Serialize, Deserialize, Debug)]
pub struct ServiceEntry {
    #[serde(rename = "Tags")]
    pub tags: Vec<String>,
}

#[derive(Serialize, Deserialize, Debug, Default)]
pub struct CatalogNode {
    #[serde(rename = "Services")]
    pub services: HashMap<String, ServiceEntry>,
}

pub struct Consul {
    client: reqwest::Client,
    url: String,
    idx: Option<u64>,
}

impl Consul {
    pub fn new(config: &RuntimeConfigConsul) -> Self {
        let client = if let Some((ca, skip_verify, ident)) = config.tls.clone() {
            if skip_verify {
                reqwest::Client::builder()
                    .use_rustls_tls()
                    .danger_accept_invalid_certs(true)
                    .identity(ident)
                    .build()
                    .expect("Unable to build reqwest client")
            } else if let Some(ca) = ca {
                reqwest::Client::builder()
                    .use_rustls_tls()
                    .add_root_certificate(ca)
                    .identity(ident)
                    .build()
                    .expect("Unable to build reqwest client")
            } else {
                reqwest::Client::builder()
                    .use_rustls_tls()
                    .identity(ident)
                    .build()
                    .expect("Unable to build reqwest client")
            }
        } else {
            reqwest::Client::new()
        };
        return Self {
            client,
            url: config.url.clone(),
            idx: None,
        };
    }

    pub fn watch_node_reset(&mut self) -> () {
        self.idx = None;
    }

    pub async fn watch_node(&mut self, host: &str) -> Result<CatalogNode> {
        let url = match self.idx {
            Some(i) => format!("{}/v1/catalog/node/{}?index={}", self.url, host, i),
            None => format!("{}/v1/catalog/node/{}", self.url, host),
        };

        let http = self.client.get(&url).send().await?;
        self.idx = match http.headers().get("X-Consul-Index") {
            Some(v) => Some(v.to_str()?.parse::<u64>()?),
            None => return Err(anyhow!("X-Consul-Index header not found")),
        };

        let resp: Option<CatalogNode> = http.json().await?;
        return Ok(resp.unwrap_or_default());
    }

    pub async fn kv_put(&self, key: &str, bytes: Vec<u8>) -> Result<()> {
        let url = format!("{}/v1/kv/{}", self.url, key);
        let http = self.client.put(&url).body(bytes).send().await?;
        http.error_for_status()?;
        Ok(())
    }
}