//! Pure AppConfig entity — provider registry, model roles, and default model
//! selections.
//!
//! # Architecture
//! This is a pure data structure with **no I/O logic**.  Load/save
//! responsibilities live in [`AppConfigRepository`](super::repository::AppConfigRepository).

#![allow(
    clippy::cast_possible_truncation,
    clippy::cast_sign_loss,
    clippy::cast_precision_loss,
    clippy::cast_possible_wrap
)]

use std::collections::HashMap;

use serde::{Deserialize, Serialize};

/// Top-level application config: registered providers, named model roles,
/// and which provider/model to use by default.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AppConfig {
    pub providers: HashMap<String, ProviderConfig>,
    pub model_roles: HashMap<String, ModelRole>,
    pub default_provider: String,
    pub default_model: String,
    pub default_context_window: u32,
}

/// Connection details for a single LLM provider.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ProviderConfig {
    pub api_base: String,
    pub api_key_env: Option<String>,
    pub default_model: Option<String>,
    pub default_api_key: Option<String>,
}

/// A named role (e.g. "default") mapping to a specific provider/model and
/// its generation parameters.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ModelRole {
    pub provider: String,
    pub model: String,
    pub max_tokens: Option<u32>,
    pub context_window: Option<u32>,
    pub temperature: Option<f32>,
}

impl Default for AppConfig {
    fn default() -> Self {
        let mut providers = HashMap::new();
        providers.insert(
            "zen".to_string(),
            ProviderConfig {
                api_base: "https://opencode.ai/zen/v1".to_string(),
                api_key_env: Some("API_KEY".to_string()),
                default_model: Some("deepseek-v4-flash-free".to_string()),
                default_api_key: None,
            },
        );
        providers.insert(
            "router".to_string(),
            ProviderConfig {
                api_base: "https://9router.asepharyana.my.id/v1".to_string(),
                api_key_env: Some("ROUTER_API_KEY".to_string()),
                default_model: Some("claude-opus-4-8".to_string()),
                default_api_key: None,
            },
        );

        let mut model_roles = HashMap::new();
        model_roles.insert(
            "default".to_string(),
            ModelRole {
                provider: "zen".to_string(),
                model: "deepseek-v4-flash-free".to_string(),
                max_tokens: None,
                context_window: None,
                temperature: Some(0.7),
            },
        );

        Self {
            providers,
            model_roles,
            default_provider: "zen".to_string(),
            default_model: "deepseek-v4-flash-free".to_string(),
            default_context_window: 256_000,
        }
    }
}