gthings-cdp 0.4.9

use crate::connection::Connection;
use crate::error::{CdpError, Result};
use serde_json::{Value, json};
use std::time::Duration;
use tracing;


/// A CDP tab session, representing one browser tab.
pub struct Tab {
    /// The CDP session ID for this tab's target
    pub session_id: String,
    /// The target ID
    pub target_id: String,
}

impl Tab {
    /// Create a new tab. Uses `Target.createTarget`; attaches via CDP if sessionId is missing.
    pub async fn create(conn: &mut Connection, _ws_url: &str, url: &str) -> Result<Self> {
        let result = conn
            .call(
                "Target.createTarget",
                json!({
                    "url": url,
                    "newWindow": false,
                }),
            )
            .await;

        if let Ok(result) = result {
            if let Some(session_id) = result.get("sessionId").and_then(|v| v.as_str()) {
                let target_id = result
                    .get("targetId")
                    .and_then(|v| v.as_str())
                    .ok_or_else(|| CdpError::CommandFailed {
                        method: "Target.createTarget".into(),
                        msg: "no targetId in response".into(),
                    })?
                    .to_string();

                tracing::debug!("Created tab: target={}, session={}", target_id, session_id);

                return Ok(Tab {
                    session_id: session_id.to_string(),
                    target_id,
                });
            }
            // Missing sessionId — Dia returns targetId without sessionId.
            // Attach to the target via CDP instead of falling back to HTTP
            // (Dia doesn't support HTTP endpoints like /json/new).
            if let Some(target_id) = result.get("targetId").and_then(|v| v.as_str()) {
                tracing::warn!(
                    "Target.createTarget returned targetId without sessionId, attaching..."
                );
                let attach = conn
                    .call(
                        "Target.attachToTarget",
                        json!({
                            "targetId": target_id,
                            "flatten": true,
                        }),
                    )
                    .await
                    .map_err(|e| CdpError::CommandFailed {
                        method: "Target.attachToTarget".into(),
                        msg: format!("attach failed: {e}"),
                    })?;

                let session_id = attach
                    .get("sessionId")
                    .and_then(|v| v.as_str())
                    .ok_or_else(|| CdpError::CommandFailed {
                        method: "Target.attachToTarget".into(),
                        msg: "no sessionId in attach response".into(),
                    })?
                    .to_string();

                tracing::info!(
                    "Attached to created target: {} (session={})",
                    target_id,
                    session_id
                );

                return Ok(Tab {
                    session_id,
                    target_id: target_id.to_string(),
                });
            }
            tracing::warn!(
                "Target.createTarget returned neither sessionId nor targetId, cannot attach"
            );
        } else {
            tracing::warn!("Target.createTarget failed");
        }

        Err(CdpError::CommandFailed {
            method: "Target.createTarget".into(),
            msg: "could not create tab: all methods exhausted".into(),
        })
    }

    /// Navigate the tab to a URL. Waits for the page to reach a stable state.
    pub async fn navigate(&self, conn: &mut Connection, url: &str) -> Result<()> {
        tracing::info!("Navigating to: {}", url);

        let result = conn
            .call_with_session(&self.session_id, "Page.enable", json!({}))
            .await?;
        tracing::debug!("Page.enable: {:?}", result);

        let _result = conn
            .call_with_session(
                &self.session_id,
                "Page.navigate",
                json!({
                    "url": url,
                }),
            )
            .await?;

        // Wait for page readyState
        self.wait_for_page_load(conn, 10000).await
    }

    /// Wait for the page to reach `complete` readyState, with partial content fallback.
    async fn wait_for_page_load(&self, conn: &mut Connection, timeout_ms: u64) -> Result<()> {
        let start = std::time::Instant::now();
        let timeout = Duration::from_millis(timeout_ms);

        loop {
            if start.elapsed() > timeout {
                tracing::warn!("Page load timed out after {}ms", timeout_ms);
                return Ok(()); // Don't fail on timeout — content may still be partial
            }

            let result = conn
                .call_with_session(
                    &self.session_id,
                    "Runtime.evaluate",
                    json!({
                        "expression": "document.readyState",
                        "returnByValue": true,
                    }),
                )
                .await?;

            let ready_state = result["result"]["value"].as_str().unwrap_or("unknown");

            if ready_state == "complete" {
                tracing::debug!("Page loaded (readyState=complete)");
                return Ok(());
            }

            // Fallback: check for partial content
            let has_content = conn.call_with_session(&self.session_id, "Runtime.evaluate", json!({
                "expression": "document.body ? document.body.innerText.length > 100 : false",
                "returnByValue": true,
            })).await?;

            if has_content["result"]["value"].as_bool().unwrap_or(false) {
                tracing::debug!("Page has sufficient content (readyState={})", ready_state);
                return Ok(());
            }

            tokio::time::sleep(Duration::from_millis(200)).await;
        }
    }

    /// Evaluate JavaScript in the tab context and return the result.
    pub async fn evaluate(&self, conn: &mut Connection, js: &str) -> Result<Value> {
        let result = conn
            .call_with_session(
                &self.session_id,
                "Runtime.evaluate",
                json!({
                    "expression": js,
                    "returnByValue": true,
                }),
            )
            .await?;

        Ok(result)
    }

    /// Extract the page content. Returns innerText of body.
    pub async fn extract_text(&self, conn: &mut Connection) -> Result<String> {
        let result = self
            .evaluate(conn, "document.body?.innerText || ''")
            .await?;
        let text = result["result"]["value"].as_str().unwrap_or("").to_string();
        Ok(text)
    }

    /// Extract the page title.
    pub async fn extract_title(&self, conn: &mut Connection) -> Result<String> {
        let result = self.evaluate(conn, "document.title || ''").await?;
        let title = result["result"]["value"].as_str().unwrap_or("").to_string();
        Ok(title)
    }

    /// Extract HTML content.
    pub async fn extract_html(&self, conn: &mut Connection) -> Result<String> {
        let result = self
            .evaluate(conn, "document.documentElement?.outerHTML || ''")
            .await?;
        let html = result["result"]["value"].as_str().unwrap_or("").to_string();
        Ok(html)
    }

    /// Execute multiple JS snippets in sequence.
    pub async fn evaluate_all(
        &self,
        conn: &mut Connection,
        scripts: &[&str],
    ) -> Result<Vec<Value>> {
        let mut results = Vec::with_capacity(scripts.len());
        for script in scripts {
            let result = self.evaluate(conn, script).await?;
            results.push(result);
        }
        Ok(results)
    }

    /// Close this tab. Uses `window.close()` first, then `Target.closeTarget` as fallback.
    /// Errors are logged but not propagated.
    pub async fn close(self, conn: &mut Connection) {
        let _ = conn
            .call_with_session(
                &self.session_id,
                "Runtime.evaluate",
                json!({
                    "expression": "window.close()",
                }),
            )
            .await;

        // Short delay for clean shutdown
        tokio::time::sleep(Duration::from_millis(200)).await;

        let _ = conn
            .call(
                "Target.closeTarget",
                json!({
                    "targetId": self.target_id,
                }),
            )
            .await;
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_tab_struct_creation() {
        let tab = Tab {
            session_id: "test-session".into(),
            target_id: "test-target".into(),
        };
        assert_eq!(tab.session_id, "test-session");
        assert_eq!(tab.target_id, "test-target");
    }
}