use std::pin::Pin;

use async_openai::types::chat::ChatCompletionTool;
use db::cache::AppCache;
use db::database::AppDatabase;
use models::agents::model;
use models::projects::project;
use models::repos::repo;
use models::rooms::{room, room_message};
use models::users::user;
use config::AppConfig;
use std::collections::HashMap;
use uuid::Uuid;

/// Maximum recursion rounds for tool-call loops (AI → tool → result → AI).
/// Previous default of 3 caused frequent silent termination on realistic multi-step queries.
pub const DEFAULT_MAX_TOOL_DEPTH: usize = 99;

/// A single chunk from an AI streaming response.
#[derive(Debug, Clone)]
pub struct AiStreamChunk {
    pub content: String,
    pub done: bool,
    /// What kind of content this chunk contains — helps the frontend render
    /// thinking, tool calls, and results with different styles.
    pub chunk_type: AiChunkType,
}

/// Type of streaming chunk, used by the frontend for rendering.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum AiChunkType {
    /// AI reasoning/thinking text before a tool call or answer.
    Thinking,
    /// Final answer text from the AI.
    Answer,
    /// A tool call is being executed (content = tool name + args summary).
    ToolCall,
    /// Tool execution result (content = result or error).
    ToolResult,
}

impl Default for AiChunkType {
    fn default() -> Self {
        Self::Answer
    }
}

/// Optional streaming callback: called for each token chunk.
pub type StreamCallback = Box<
    dyn Fn(AiStreamChunk) -> Pin<Box<dyn std::future::Future<Output = ()> + Send>> + Send + Sync,
>;

pub struct AiRequest {
    pub db: AppDatabase,
    pub cache: AppCache,
    pub config: AppConfig,
    pub model: model::Model,
    pub project: project::Model,
    pub sender: user::Model,
    pub room: room::Model,
    pub input: String,
    pub mention: Vec<Mention>,
    pub history: Vec<room_message::Model>,
    pub user_names: HashMap<Uuid, String>,
    pub temperature: f64,
    pub max_tokens: i32,
    pub top_p: f64,
    pub frequency_penalty: f64,
    pub presence_penalty: f64,
    pub think: bool,
    pub tools: Option<Vec<ChatCompletionTool>>,
    pub max_tool_depth: usize,
}

pub enum Mention {
    User(user::Model),
    Repo(repo::Model),
}

pub mod context;
pub mod service;
pub use context::{AiContextSenderType, RoomMessageContext};
pub use service::ChatService;