//! OAuth2 provider implementations.
//!
//! Implements OAuth2 authentication for various email providers:
//! - Fastmail (JMAP)
//! - Google/Gmail (Gmail API + IMAP XOAUTH2)
//! - Microsoft/Outlook (Graph API + IMAP XOAUTH2)

pub mod fastmail;
pub mod google;
pub mod microsoft;
pub use fastmail::FastmailProvider;
pub use google::GoogleProvider;
pub use microsoft::MicrosoftProvider;

use super::provider::OAuthProvider;
use goingson_core::EmailAuthType;

/// Registry of all supported OAuth providers.
pub struct ProviderRegistry {
    providers: Vec<Box<dyn OAuthProvider>>,
}

impl ProviderRegistry {
    /// Creates a new provider registry with default provider configurations.
    ///
    /// Client IDs should be loaded from environment or configuration.
    pub fn new(config: ProviderConfig) -> Self {
        let mut providers: Vec<Box<dyn OAuthProvider>> = Vec::new();

        if let Some(client_id) = config.fastmail_client_id {
            providers.push(Box::new(FastmailProvider::new(client_id)));
        }

        if let (Some(client_id), Some(client_secret)) = (config.google_client_id, config.google_client_secret) {
            providers.push(Box::new(GoogleProvider::new(client_id, client_secret)));
        }

        if let Some(client_id) = config.microsoft_client_id {
            providers.push(Box::new(MicrosoftProvider::new(client_id, config.microsoft_client_secret)));
        }

        Self { providers }
    }

    /// Returns a list of available provider IDs.
    pub fn available_providers(&self) -> Vec<&'static str> {
        self.providers.iter().map(|p| p.id()).collect()
    }

    /// Gets a provider by its ID.
    pub fn get(&self, id: &str) -> Option<&dyn OAuthProvider> {
        self.providers.iter().find(|p| p.id() == id).map(|p| p.as_ref())
    }

    /// Gets the auth type for a provider ID.
    pub fn auth_type_for(id: &str) -> EmailAuthType {
        match id {
            "fastmail" => EmailAuthType::OAuth2Fastmail,
            // Future providers will have their own EmailAuthType variants
            _ => EmailAuthType::Password,
        }
    }
}

/// Configuration for OAuth providers.
///
/// Client IDs and secrets should be loaded from environment variables
/// or a configuration file.
#[derive(Debug, Clone, Default)]
pub struct ProviderConfig {
    /// Fastmail OAuth client ID.
    pub fastmail_client_id: Option<String>,

    /// Google OAuth client ID.
    pub google_client_id: Option<String>,
    /// Google OAuth client secret.
    pub google_client_secret: Option<String>,

    /// Microsoft OAuth client ID.
    pub microsoft_client_id: Option<String>,
    /// Microsoft OAuth client secret.
    pub microsoft_client_secret: Option<String>,

}

impl ProviderConfig {
    /// Loads provider configuration from environment variables.
    pub fn from_env() -> Self {
        Self {
            fastmail_client_id: std::env::var("GOINGSON_FASTMAIL_CLIENT_ID").ok(),
            google_client_id: std::env::var("GOINGSON_GOOGLE_CLIENT_ID").ok(),
            google_client_secret: std::env::var("GOINGSON_GOOGLE_CLIENT_SECRET").ok(),
            microsoft_client_id: std::env::var("GOINGSON_MICROSOFT_CLIENT_ID").ok(),
            microsoft_client_secret: std::env::var("GOINGSON_MICROSOFT_CLIENT_SECRET").ok(),
        }
    }
}