//! Run-package provenance for the report table: one bench run's recipe
//! copy + served-image identity, parsed from `<stem>.manifest.json`
//! (written by `sm121 bench`, see [`crate::bench_artifacts`]).
//!
//! The report also flags **drift**: the manifest's recipe SHA-256 vs the
//! current `recipe.toml` — a run whose recipe has since changed shows ⚠,
//! so "what did this bench actually test?" is always answerable.

use crate::bench_artifacts::{Manifest, short12};
use crate::report::ReportRow;
use serde::{Deserialize, Serialize};

/// Run package provenance for one bench run. Empty fields for runs that
/// predate the run package.
#[derive(Serialize, Deserialize, Default, Debug, Clone)]
pub struct Provenance {
    /// 12-char SHA-256 of the recipe copy captured at bench time.
    pub recipe_sha: String,
    /// True when the current recipe.toml's SHA-256 differs from the one
    /// captured at bench time — the report may no longer represent the
    /// recipe as it stands now.
    pub recipe_drift: bool,
    /// Docker image name from the manifest.
    pub image: String,
    /// `sm121.checksum` build label of the image (short hex).
    pub image_sum: String,
    /// Docker image id (first 12 hex chars) as seen on a launch node.
    pub image_id: String,
    /// tool-eval-bench version string from the run's JSON.
    pub tool: String,
    /// Launcher git commit (first 12 hex chars) that ran the bench.
    pub launcher: String,
}

/// Parse a `<stem>.manifest.json` body into provenance; `None` when the
/// body is not a valid manifest (the entry then falls back to the empty
/// shape, as for runs without a package).
pub fn from_manifest(content: &str, current_recipe_sha: &str) -> Option<Provenance> {
    let m: Manifest = serde_json::from_str(content).ok()?;
    let (image, image_sum, image_id) = m
        .images
        .iter()
        .next()
        .map(|(name, val)| {
            let sum = val
                .get("build_checksum")
                .and_then(|v| v.as_str())
                .unwrap_or_default();
            let id = val
                .get("nodes")
                .and_then(|v| v.as_object())
                .and_then(|n| n.values().next())
                .and_then(|n| n.get("id"))
                .and_then(|v| v.as_str())
                .map(|id| short12(id.strip_prefix("sha256:").unwrap_or(id)))
                .unwrap_or_default();
            (name.clone(), sum.to_string(), id)
        })
        .unwrap_or_default();
    Some(Provenance {
        recipe_sha: short12(&m.recipe.sha256),
        recipe_drift: m.recipe.sha256 != current_recipe_sha,
        image,
        image_sum,
        image_id,
        tool: m.bench.version.unwrap_or_default(),
        launcher: m
            .launcher
            .git_sha
            .as_deref()
            .map(short12)
            .unwrap_or_default(),
    })
}

/// Latest report entry carrying a run package (newest first); the row's
/// provenance cell mirrors what the run's chip shows in the web UI.
pub fn latest(r: &ReportRow) -> Option<&Provenance> {
    r.reports
        .iter()
        .rev()
        .find(|e| !e.provenance.recipe_sha.is_empty() || !e.provenance.image_sum.is_empty())
        .map(|e| &e.provenance)
}

/// `img@<buildsum>·rcp@<sha12>` (+ ⚠ on drift) for the markdown table.
pub fn cell(r: &ReportRow) -> String {
    latest(r)
        .map(|p| {
            let sum = p.image_sum.chars().take(12).collect::<String>();
            let mut s = format!("img@{sum}·rcp@{}", p.recipe_sha);
            if p.recipe_drift {
                s.push_str(" ⚠");
            }
            s
        })
        .unwrap_or_else(|| "—".into())
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::config::Config;
    use crate::report::collect;
    use crate::report::tests::fixture;
    use std::fs;

    #[test]
    fn manifest_parses_and_drifts() {
        use crate::bench_artifacts::sha256_hex;
        let dir = fixture();
        let recipe_path = dir.join("test-recipe-nvfp4/recipe.toml");
        let recipe = fs::read_to_string(&recipe_path).unwrap();
        // run package for the roce-run stem: manifest + recipe copy
        let stem = "2026-01-04_roce-run";
        fs::write(
            dir.join(format!("test-recipe-nvfp4/reports/{stem}.manifest.json")),
            format!(
                "{{\"schema_version\":1,\"run\":\"{stem}\",\"created_utc\":\"x\",\"recipe\":{{\"name\":\"Test Recipe\",\"file\":\"x\",\"sha256\":\"{}\"}},\"cluster\":{{\"name\":\"c\",\"nodes\":[]}},\"launcher\":{{\"bin\":\"b\",\"git_sha\":\"deadbeefcafe42\"}},\"bench\":{{\"tool\":\"tool-eval-bench\",\"version\":\"2.6.1.dev99\",\"args\":[]}},\"images\":{{\"img:tag\":{{\"build_checksum\":\"8bb87348\",\"nodes\":{{\"dgx1\":{{\"id\":\"sha256:abcdef1234567890\",\"sm121_checksum\":\"8bb87348\"}}}}}}}}}}",
                sha256_hex(recipe.as_bytes())
            ),
        )
        .unwrap();
        fs::write(
            dir.join(format!("test-recipe-nvfp4/reports/{stem}.recipe.toml")),
            &recipe,
        )
        .unwrap();
        let mk_config = || {
            toml::from_str::<Config>(&format!("recipe_sources = [\"{}\"]", dir.to_str().unwrap()))
                .unwrap()
        };

        // no drift: manifest sha == current recipe sha
        let rows = collect(&mk_config(), false);
        let row = rows.iter().find(|r| r.name == "test-recipe-nvfp4").unwrap();
        let e = row.reports.iter().find(|e| e.label == "roce-run").unwrap();
        assert_eq!(e.provenance.image_sum, "8bb87348");
        assert_eq!(e.provenance.image, "img:tag");
        assert_eq!(e.provenance.image_id, "abcdef123456");
        assert_eq!(e.provenance.tool, "2.6.1.dev99");
        assert_eq!(e.provenance.launcher, "deadbeefcafe");
        assert_eq!(
            e.provenance.recipe_sha,
            &sha256_hex(recipe.as_bytes())[..12]
        );
        assert!(!e.provenance.recipe_drift);
        // run-package files ride on the run's stem (links in the UI)
        assert!(e.files.contains(&format!("{stem}.manifest.json")));
        assert!(e.files.contains(&format!("{stem}.recipe.toml")));
        // the score still comes from the REPORT json, not the manifest
        assert_eq!(e.pct, Some(92.0));
        // the markdown row carries the provenance cell
        assert!(cell(row).starts_with("img@8bb87348·rcp@"));

        // drift: the recipe changed since the bench
        fs::write(&recipe_path, recipe + "port = 30001\n").unwrap();
        let rows = collect(&mk_config(), false);
        let row = rows.iter().find(|r| r.name == "test-recipe-nvfp4").unwrap();
        let e = row.reports.iter().find(|e| e.label == "roce-run").unwrap();
        assert!(e.provenance.recipe_drift, "recipe changed after the run");
        assert!(cell(row).ends_with('⚠'));
        fs::remove_dir_all(&dir).ok();
    }

    #[test]
    fn bad_manifest_yields_empty_provenance() {
        assert!(from_manifest("not json", "x").is_none());
        // complete manifest, empty images + drifted sha
        let m = from_manifest(
            r#"{"schema_version":1,"run":"r","created_utc":"x","recipe":{"name":"n","file":"f","sha256":"a"},"cluster":{"name":"c","nodes":[]},"launcher":{"bin":"b"},"bench":{"tool":"t","args":[]},"images":{}}"#,
            "b",
        )
        .unwrap();
        assert!(m.recipe_drift, "a != b");
        assert!(m.image.is_empty());
    }
}