//! Version check against Gitea releases API.

use serde::Serialize;

#[derive(Debug, Serialize)]
#[serde(rename_all = "camelCase")]
pub struct UpdateInfo {
    pub current_version: String,
    pub latest_version: String,
    pub update_available: bool,
    pub download_url: String,
    pub release_notes: String,
}

/// Check Gitea for the latest release and compare with current version.
#[tauri::command]
pub async fn check_for_updates(app_handle: tauri::AppHandle) -> Result<UpdateInfo, String> {
    // Read version from tauri.conf.json (patched by CI from git tag)
    // rather than CARGO_PKG_VERSION which is always 0.1.0
    let current = app_handle.config().version.clone().unwrap_or_else(|| "0.0.0".to_string());

    let client = reqwest::Client::builder()
        .timeout(std::time::Duration::from_secs(10))
        .build()
        .map_err(|e| format!("HTTP client error: {}", e))?;

    let resp = client
        .get("https://git.command.vigilcyber.com/api/v1/repos/vstockwell/wraith/releases?limit=1")
        .header("Accept", "application/json")
        .send()
        .await
        .map_err(|e| format!("Failed to check for updates: {}", e))?;

    let releases: Vec<serde_json::Value> = resp.json().await
        .map_err(|e| format!("Failed to parse releases: {}", e))?;

    let latest = releases.first()
        .ok_or_else(|| "No releases found".to_string())?;

    let tag = latest.get("tag_name")
        .and_then(|v| v.as_str())
        .unwrap_or("v0.0.0")
        .trim_start_matches('v')
        .to_string();

    let notes = latest.get("body")
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();

    let html_url = latest.get("html_url")
        .and_then(|v| v.as_str())
        .unwrap_or("https://git.command.vigilcyber.com/vstockwell/wraith/releases")
        .to_string();

    let update_available = version_is_newer(&tag, &current);

    Ok(UpdateInfo {
        current_version: current,
        latest_version: tag,
        update_available,
        download_url: html_url,
        release_notes: notes,
    })
}

/// Compare semver strings. Returns true if `latest` is newer than `current`.
fn version_is_newer(latest: &str, current: &str) -> bool {
    let parse = |v: &str| -> Vec<u32> {
        v.split('.').filter_map(|s| s.parse().ok()).collect()
    };
    let l = parse(latest);
    let c = parse(current);
    for i in 0..3 {
        let lv = l.get(i).copied().unwrap_or(0);
        let cv = c.get(i).copied().unwrap_or(0);
        if lv > cv { return true; }
        if lv < cv { return false; }
    }
    false
}

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

    #[test]
    fn version_comparison() {
        assert!(version_is_newer("1.5.7", "1.5.6"));
        assert!(version_is_newer("1.6.0", "1.5.9"));
        assert!(version_is_newer("2.0.0", "1.9.9"));
        assert!(!version_is_newer("1.5.6", "1.5.6"));
        assert!(!version_is_newer("1.5.5", "1.5.6"));
        assert!(!version_is_newer("1.4.0", "1.5.0"));
    }
}