// Page — continuation token carrier. Mirrors NPE Page.java.
//
// Used everywhere "the next page" is paginated through an opaque token
// (search results, channel videos, playlist videos, comments). The fields
// are deliberately a grab-bag — NPE callers stuff whatever they need to
// resume.

use std::collections::BTreeMap;

#[derive(Clone, Debug, Default)]
pub struct Page {
    url: Option<String>,
    id: Option<String>,
    ids: Vec<String>,
    body: Option<Vec<u8>>,
    cookies: BTreeMap<String, String>,
}

impl Page {
    pub fn new() -> Self {
        Self::default()
    }

    pub fn with_url(url: impl Into<String>) -> Self {
        Self { url: Some(url.into()), ..Self::default() }
    }

    pub fn url(&self) -> Option<&str> {
        self.url.as_deref()
    }

    pub fn set_url(&mut self, url: Option<String>) -> &mut Self {
        self.url = url;
        self
    }

    pub fn id(&self) -> Option<&str> {
        self.id.as_deref()
    }

    pub fn set_id(&mut self, id: Option<String>) -> &mut Self {
        self.id = id;
        self
    }

    pub fn ids(&self) -> &[String] {
        &self.ids
    }

    pub fn set_ids(&mut self, ids: Vec<String>) -> &mut Self {
        self.ids = ids;
        self
    }

    pub fn body(&self) -> Option<&[u8]> {
        self.body.as_deref()
    }

    pub fn set_body(&mut self, body: Option<Vec<u8>>) -> &mut Self {
        self.body = body;
        self
    }

    pub fn cookies(&self) -> &BTreeMap<String, String> {
        &self.cookies
    }

    pub fn set_cookies(&mut self, cookies: BTreeMap<String, String>) -> &mut Self {
        self.cookies = cookies;
        self
    }

    pub fn is_valid(&self) -> bool {
        self.url.as_deref().map(|s| !s.is_empty()).unwrap_or(false)
            || self.id.as_deref().map(|s| !s.is_empty()).unwrap_or(false)
            || !self.ids.is_empty()
            || self.body.as_ref().map(|b| !b.is_empty()).unwrap_or(false)
    }
}