//! ACME plugin configuration helpers (SectionConfig implementation)

use anyhow::Error;
use lazy_static::lazy_static;
use serde_json::Value;

use proxmox_schema::{ApiType, Schema};
use proxmox_section_config::{SectionConfig, SectionConfigData, SectionConfigPlugin};

use crate::config::AcmeApiConfig;
use crate::types::{PLUGIN_ID_SCHEMA, DnsPlugin, StandalonePlugin};

lazy_static! {
    static ref CONFIG: SectionConfig = init();
}

impl DnsPlugin {
    pub fn decode_data(&self, output: &mut Vec<u8>) -> Result<(), Error> {
        Ok(base64::decode_config_buf(
            &self.data,
            base64::URL_SAFE_NO_PAD,
            output,
        )?)
    }
}

fn init() -> SectionConfig {
    let mut config = SectionConfig::new(&PLUGIN_ID_SCHEMA);

    let standalone_schema = match &StandalonePlugin::API_SCHEMA {
        Schema::Object(schema) => schema,
        _ => unreachable!(),
    };
    let standalone_plugin = SectionConfigPlugin::new(
        "standalone".to_string(),
        Some("id".to_string()),
        standalone_schema,
    );
    config.register_plugin(standalone_plugin);

    let dns_challenge_schema = match DnsPlugin::API_SCHEMA {
        Schema::AllOf(ref schema) => schema,
        _ => unreachable!(),
    };
    let dns_challenge_plugin = SectionConfigPlugin::new(
        "dns".to_string(),
        Some("id".to_string()),
        dns_challenge_schema,
    );
    config.register_plugin(dns_challenge_plugin);

    config
}

// LockGuard for the plugin configuration
pub(crate) struct AcmePluginConfigLockGuard {
    _file: Option<std::fs::File>,
}

impl AcmeApiConfig {
    pub(crate) fn lock_plugin_config(&self) -> Result<AcmePluginConfigLockGuard, Error> {
        self.make_acme_dir()?;
        let file_owner = (self.file_owner)();

        let mode = nix::sys::stat::Mode::from_bits_truncate(0o0660);
        let options = proxmox_sys::fs::CreateOptions::new()
            .perm(mode)
            .owner(file_owner.uid)
            .group(file_owner.gid);

        let timeout = std::time::Duration::new(10, 0);

        let plugin_cfg_lockfile = self.plugin_cfg_lockfile();
        let file = proxmox_sys::fs::open_file_locked(&plugin_cfg_lockfile, timeout, true, options)?;
        Ok(AcmePluginConfigLockGuard { _file: Some(file) })
    }

    pub(crate) fn plugin_config(&self) -> Result<(PluginData, [u8; 32]), Error> {
        let plugin_cfg_filename = self.plugin_cfg_filename();

        let content =
            proxmox_sys::fs::file_read_optional_string(&plugin_cfg_filename)?.unwrap_or_default();

        let digest = openssl::sha::sha256(content.as_bytes());
        let mut data = CONFIG.parse(&plugin_cfg_filename, &content)?;

        if data.sections.get("standalone").is_none() {
            let standalone = StandalonePlugin::default();
            data.set_data("standalone", "standalone", &standalone)
                .unwrap();
        }

        Ok((PluginData { data }, digest))
    }

    pub(crate) fn save_plugin_config(&self, config: &PluginData) -> Result<(), Error> {
        self.make_acme_dir()?;
        let plugin_cfg_filename = self.plugin_cfg_filename();
        let raw = CONFIG.write(&plugin_cfg_filename, &config.data)?;
        let file_owner = (self.file_owner)();

        let mode = nix::sys::stat::Mode::from_bits_truncate(0o0640);
        // set the correct owner/group/permissions while saving file
        let options = proxmox_sys::fs::CreateOptions::new()
            .perm(mode)
            .owner(file_owner.uid)
            .group(file_owner.gid);

        proxmox_sys::fs::replace_file(plugin_cfg_filename, raw.as_bytes(), options, true)
    }
}

pub(crate) struct PluginData {
    data: SectionConfigData,
}

// And some convenience helpers.
impl PluginData {
    pub fn remove(&mut self, name: &str) -> Option<(String, Value)> {
        self.data.sections.remove(name)
    }

    pub fn contains_key(&mut self, name: &str) -> bool {
        self.data.sections.contains_key(name)
    }

    pub fn get(&self, name: &str) -> Option<&(String, Value)> {
        self.data.sections.get(name)
    }

    pub fn get_mut(&mut self, name: &str) -> Option<&mut (String, Value)> {
        self.data.sections.get_mut(name)
    }

    pub fn insert(&mut self, id: String, ty: String, plugin: Value) {
        self.data.sections.insert(id, (ty, plugin));
    }

    pub fn iter(&self) -> impl Iterator<Item = (&String, &(String, Value))> + Send {
        self.data.sections.iter()
    }
}