use std::path::Path;

use serde::Deserialize;

#[derive(Debug, Deserialize)]
pub struct BridgeConfig {
    pub irc: IrcConfig,
    pub owncast: OwncastConfig,
    #[serde(default)]
    pub bridge: BridgeSettings,
    #[serde(default)]
    pub control: ControlConfig,
}

#[derive(Debug, Clone, Deserialize)]
pub struct IrcConfig {
    pub server: String,
    #[serde(default = "default_irc_port")]
    pub port: u16,
    #[serde(default)]
    pub tls: bool,
    #[serde(default = "default_nick")]
    pub nick: String,
    pub channel: String,
}

#[derive(Debug, Deserialize)]
pub struct OwncastConfig {
    pub url: String,
    #[serde(default = "default_webhook_port")]
    pub webhook_port: u16,
    #[serde(default)]
    pub websocket_enabled: bool,
    #[serde(default = "default_health_poll_interval")]
    pub health_poll_interval_secs: u64,
}

#[derive(Debug, Deserialize)]
pub struct BridgeSettings {
    #[serde(default = "default_irc_prefix")]
    pub irc_prefix: String,
    #[serde(default = "default_owncast_prefix")]
    pub owncast_prefix: String,
    #[serde(default)]
    pub message_buffer_size: usize,
}

#[derive(Debug, Deserialize)]
pub struct ControlConfig {
    #[serde(default = "default_socket_path")]
    pub socket_path: String,
}

impl BridgeConfig {
    pub fn load(path: &Path) -> anyhow::Result<Self> {
        let contents = std::fs::read_to_string(path)?;
        let config: BridgeConfig = toml::from_str(&contents)?;
        Ok(config)
    }

    pub fn owncast_access_token(&self) -> anyhow::Result<String> {
        std::env::var("OWNCAST_ACCESS_TOKEN")
            .map_err(|_| anyhow::anyhow!("OWNCAST_ACCESS_TOKEN env var not set"))
    }
}

fn default_irc_port() -> u16 { 6667 }
fn default_nick() -> String { "owncast-bridge".to_string() }
fn default_webhook_port() -> u16 { 9078 }
fn default_health_poll_interval() -> u64 { 30 }
fn default_irc_prefix() -> String { "[IRC]".to_string() }
fn default_owncast_prefix() -> String { "[OC]".to_string() }
fn default_socket_path() -> String { "/tmp/owncast-irc-bridge.sock".to_string() }

impl Default for BridgeSettings {
    fn default() -> Self {
        Self {
            irc_prefix: default_irc_prefix(),
            owncast_prefix: default_owncast_prefix(),
            message_buffer_size: 0,
        }
    }
}

impl Default for ControlConfig {
    fn default() -> Self {
        Self { socket_path: default_socket_path() }
    }
}

#[cfg(test)]
impl BridgeConfig {
    pub fn default_for_test() -> Self {
        Self {
            irc: IrcConfig {
                server: "localhost".to_string(),
                port: 6667,
                tls: false,
                nick: "test-bot".to_string(),
                channel: "#test".to_string(),
            },
            owncast: OwncastConfig {
                url: "http://localhost:8080".to_string(),
                webhook_port: 9078,
                websocket_enabled: false,
                health_poll_interval_secs: 30,
            },
            bridge: BridgeSettings::default(),
            control: ControlConfig::default(),
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_parse_minimal_config() {
        let toml_str = r##"
[irc]
server = "irc.example.com"
channel = "#test"

[owncast]
url = "https://owncast.example.com"
"##;
        let config: BridgeConfig = toml::from_str(toml_str).unwrap();
        assert_eq!(config.irc.server, "irc.example.com");
        assert_eq!(config.irc.port, 6667);
        assert_eq!(config.irc.tls, false);
        assert_eq!(config.irc.nick, "owncast-bridge");
        assert_eq!(config.irc.channel, "#test");
        assert_eq!(config.owncast.url, "https://owncast.example.com");
        assert_eq!(config.owncast.webhook_port, 9078);
        assert_eq!(config.owncast.websocket_enabled, false);
        assert_eq!(config.owncast.health_poll_interval_secs, 30);
        assert_eq!(config.bridge.irc_prefix, "[IRC]");
        assert_eq!(config.bridge.owncast_prefix, "[OC]");
        assert_eq!(config.bridge.message_buffer_size, 0);
        assert_eq!(config.control.socket_path, "/tmp/owncast-irc-bridge.sock");
    }

    #[test]
    fn test_parse_full_config() {
        let toml_str = r##"
[irc]
server = "irc.example.com"
port = 6697
tls = true
nick = "mybot"
channel = "#mychan"

[owncast]
url = "https://oc.example.com"
webhook_port = 8888
websocket_enabled = true
health_poll_interval_secs = 10

[bridge]
irc_prefix = "<IRC>"
owncast_prefix = "<OC>"
message_buffer_size = 50

[control]
socket_path = "/var/run/bridge.sock"
"##;
        let config: BridgeConfig = toml::from_str(toml_str).unwrap();
        assert_eq!(config.irc.port, 6697);
        assert!(config.irc.tls);
        assert_eq!(config.irc.nick, "mybot");
        assert_eq!(config.owncast.webhook_port, 8888);
        assert!(config.owncast.websocket_enabled);
        assert_eq!(config.bridge.message_buffer_size, 50);
        assert_eq!(config.control.socket_path, "/var/run/bridge.sock");
    }

    #[test]
    fn test_access_token_from_env() {
        std::env::set_var("OWNCAST_ACCESS_TOKEN", "test-token-123");
        let config = BridgeConfig::default_for_test();
        let token = config.owncast_access_token();
        assert_eq!(token.unwrap(), "test-token-123");
        std::env::remove_var("OWNCAST_ACCESS_TOKEN");
    }
}