use crate::command::adapter::{AdapterError, InputAdapter};
use crate::command::context::AdapterContext;
use crate::command::Command;

/// Channel 输入适配器
///
/// 将 Channel 消息中的文本命令（如 "/new", "/save"）转换为 Command
pub struct ChannelInputAdapter;

impl ChannelInputAdapter {
    /// 创建新的 Channel 输入适配器
    pub fn new() -> Self {
        Self
    }
}

impl Default for ChannelInputAdapter {
    fn default() -> Self {
        Self::new()
    }
}

impl InputAdapter for ChannelInputAdapter {
    fn try_parse(
        &self,
        input: &str,
        _ctx: AdapterContext,
    ) -> Result<Option<Command>, AdapterError> {
        let trimmed = input.trim();

        // 解析 /new 命令
        if trimmed == "/new" {
            return Ok(Some(Command::CreateSession { title: None }));
        }

        if let Some(title) = trimmed.strip_prefix("/new ") {
            let title = title.trim();
            return Ok(Some(Command::CreateSession {
                title: Some(title.to_string()),
            }));
        }

        // 解析 /save 命令
        if trimmed == "/save" {
            return Ok(Some(Command::SaveSession {
                filepath: None,
                include_all: false,
            }));
        }

        if let Some(args) = trimmed.strip_prefix("/save ") {
            let args = args.trim();
            // 解析参数：可能是 "all"、路径、或 "all 路径"
            let (include_all, filepath) = if args == "all" {
                // /save all - 保存全部消息
                (true, None)
            } else if args.starts_with("all ") {
                // /save all <filepath> - 保存全部消息到指定路径
                let path = args[4..].trim();
                (true, Some(path.to_string()))
            } else {
                // /save <filepath> - 保存活跃消息到指定路径
                (false, Some(args.to_string()))
            };
            return Ok(Some(Command::SaveSession { filepath, include_all }));
        }

        // 解析 /list 命令
        if trimmed == "/list" {
            return Ok(Some(Command::ListSessions {
                include_archived: false,
            }));
        }

        if trimmed == "/list all" {
            return Ok(Some(Command::ListSessions {
                include_archived: true,
            }));
        }

        // 解析 /use 命令 - 切换会话（支持 session_id 或序号）
        if let Some(session_id) = trimmed.strip_prefix("/use ") {
            let session_id = session_id.trim();
            return Ok(Some(Command::SwitchSession {
                session_id: session_id.to_string(),
            }));
        }

        // 解析 /current 命令 - 获取当前会话信息
        if trimmed == "/current" {
            return Ok(Some(Command::GetCurrentSession));
        }

        // 不是命令，返回 None
        Ok(None)
    }
}