use async_trait::async_trait;
use serde::{Deserialize, Serialize};
use serde_json::Value;

/// Role in a conversation
#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
#[serde(rename_all = "lowercase")]
pub enum Role {
    User,
    Assistant,
    System,
    Tool,
}

/// A message in the conversation
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Message {
    pub role: Role,
    pub content: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub tool_call_id: Option<String>,
}

impl Message {
    pub fn user(content: impl Into<String>) -> Self {
        Self {
            role: Role::User,
            content: content.into(),
            tool_call_id: None,
        }
    }

    pub fn assistant(content: impl Into<String>) -> Self {
        Self {
            role: Role::Assistant,
            content: content.into(),
            tool_call_id: None,
        }
    }

    pub fn system(content: impl Into<String>) -> Self {
        Self {
            role: Role::System,
            content: content.into(),
            tool_call_id: None,
        }
    }

    pub fn tool_result(tool_call_id: impl Into<String>, content: impl Into<String>) -> Self {
        Self {
            role: Role::Tool,
            content: content.into(),
            tool_call_id: Some(tool_call_id.into()),
        }
    }
}

/// Definition of a tool that can be called by the LLM
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ToolDefinition {
    pub name: String,
    pub description: String,
    pub parameters: Value,
}

/// A tool call requested by the LLM
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ToolCall {
    pub id: String,
    pub name: String,
    pub parameters: Value,
}

/// Result of executing a tool
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ToolResult {
    pub success: bool,
    pub output: String,
}

/// Content of a response from the LLM
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(untagged)]
pub enum ResponseContent {
    Text(String),
    ToolCalls(Vec<ToolCall>),
}

/// Response from the LLM
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Response {
    pub content: ResponseContent,
    pub stop_reason: Option<String>,
}

/// Trait for LLM client implementations
#[async_trait]
pub trait LlmClient: Send + Sync {
    async fn chat(
        &self,
        messages: Vec<Message>,
        tools: &[ToolDefinition],
    ) -> anyhow::Result<Response>;
}

pub mod anthropic;
pub mod error;
pub mod factory;
pub mod mock;
pub mod ollama;
pub mod openai;
pub mod retry;