seshat-cli 0.3.1

//! `seshat debug-snippets` command — dumps every convention from the DB
//! with full evidence for offline inspection.
//!
//! Hidden CLI command (registered with `#[command(hide = true)]`); no
//! stable user-facing contract. Used to bisect snippet-extraction
//! regressions on real repositories.

use std::path::Path;

use serde::Deserialize;

use crate::error::CliError;

/// One evidence row as deserialised from `nodes.ext_data` JSON.
///
/// `snippet` lives under two historical shapes:
/// - bare string (legacy)
/// - `{ "content": "..." }` object (current `CodeSnippet`)
///
/// `Snippet`'s custom Deserialize collapses both into a single String.
#[derive(Debug, Deserialize)]
struct EvidenceRow {
    #[serde(default)]
    file: String,
    #[serde(default)]
    line: u64,
    #[serde(default)]
    end_line: u64,
    #[serde(default)]
    snippet: Snippet,
    #[serde(default)]
    snippet_start_line: u64,
}

/// Wrapper that accepts both the bare-string and the
/// `{"content": "..."}` snippet shapes the DB has carried at various
/// schema versions.
#[derive(Debug, Default)]
struct Snippet(String);

impl Snippet {
    fn as_str(&self) -> &str {
        &self.0
    }
}

impl<'de> Deserialize<'de> for Snippet {
    fn deserialize<D: serde::Deserializer<'de>>(d: D) -> Result<Self, D::Error> {
        #[derive(Deserialize)]
        #[serde(untagged)]
        enum Either {
            Bare(String),
            Object { content: String },
        }
        match Either::deserialize(d)? {
            Either::Bare(s) => Ok(Snippet(s)),
            Either::Object { content } => Ok(Snippet(content)),
        }
    }
}

/// Top-level shape of `nodes.ext_data` we care about — only the
/// evidence array. Other fields are ignored.
#[derive(Debug, Default, Deserialize)]
struct ExtData {
    #[serde(default)]
    evidence: Vec<EvidenceRow>,
}

/// One DB row that survives the SELECT projection.
struct NodeRow {
    description: String,
    nature: String,
    weight: String,
    confidence: f64,
    adoption_count: u32,
    total_count: u32,
    ext_data: Option<String>,
}

pub fn run_debug(db_path: &Path, branch_id: &str) -> Result<(), CliError> {
    let conn = rusqlite::Connection::open(db_path).map_err(|e| CliError::CommandFailed {
        command: "debug".to_owned(),
        reason: format!("failed to open database: {e}"),
    })?;

    let sql = "
        SELECT description, nature, weight, confidence,
               adoption_count, total_count, ext_data
        FROM nodes
        WHERE nature IN ('convention', 'observation')
          AND branch_id = ?1
          AND (json_extract(ext_data, '$.user_rejected') IS NULL
               OR json_extract(ext_data, '$.user_rejected') != 1)
          AND (json_extract(ext_data, '$.source') IS NULL
               OR json_extract(ext_data, '$.source') != 'user')
        ORDER BY confidence DESC
    ";

    let mut stmt = conn.prepare(sql).map_err(|e| CliError::CommandFailed {
        command: "debug".to_owned(),
        reason: e.to_string(),
    })?;

    let rows = stmt
        .query_map(rusqlite::params![branch_id], |row| {
            Ok(NodeRow {
                description: row.get(0)?,
                nature: row.get(1)?,
                weight: row.get(2)?,
                confidence: row.get(3)?,
                adoption_count: row.get(4)?,
                total_count: row.get(5)?,
                ext_data: row.get(6)?,
            })
        })
        .map_err(|e| CliError::CommandFailed {
            command: "debug".to_owned(),
            reason: e.to_string(),
        })?;

    // A single malformed row used to abort the entire dump via `?`.
    // The whole point of debug-snippets is "show what's there"; one
    // bad ext_data shouldn't blank the rest of the report.
    for (idx, row_result) in rows.enumerate() {
        let row = match row_result {
            Ok(r) => r,
            Err(e) => {
                eprintln!("  [warn] row {} skipped: {e}", idx + 1);
                continue;
            }
        };
        print_node(idx + 1, &row);
    }

    Ok(())
}

fn print_node(idx: usize, row: &NodeRow) {
    let conf_pct = (row.confidence.clamp(0.0, 1.0) * 100.0).round() as u32;
    let adoption_pct = if row.total_count > 0 {
        ((f64::from(row.adoption_count) / f64::from(row.total_count)) * 100.0).round() as u32
    } else {
        0
    };

    println!(
        "═══ {idx}/─ {desc} ═══ {nature}|{weight}|{conf_pct}% | {adopt}/{total} ({adoption_pct}%)",
        desc = row.description,
        nature = row.nature,
        weight = row.weight,
        adopt = row.adoption_count,
        total = row.total_count,
    );

    let ext: ExtData = row
        .ext_data
        .as_deref()
        .and_then(|s| match serde_json::from_str(s) {
            Ok(d) => Some(d),
            Err(e) => {
                eprintln!("  [warn] malformed ext_data: {e}");
                None
            }
        })
        .unwrap_or_default();

    if ext.evidence.is_empty() {
        println!("  [no evidence]");
        return;
    }

    for (ei, item) in ext.evidence.iter().enumerate() {
        print_evidence(ei, item);
    }
}

fn print_evidence(ei: usize, item: &EvidenceRow) {
    let file = if item.file.is_empty() {
        "?"
    } else {
        item.file.as_str()
    };
    let line = u32::try_from(item.line).unwrap_or(u32::MAX);
    let end_line = u32::try_from(if item.end_line == 0 {
        item.line
    } else {
        item.end_line
    })
    .unwrap_or(u32::MAX);
    let snippet_start_line = u32::try_from(item.snippet_start_line).unwrap_or(0);
    let snippet = item.snippet.as_str();

    println!(
        "  [{ei}] {file}  line={line}..{end_line}  ssl={snippet_start_line}  snippet_len={}",
        snippet.len(),
    );
    if snippet.is_empty() {
        return;
    }
    for (li, l) in snippet.lines().enumerate() {
        let actual_line = if snippet_start_line > 0 {
            snippet_start_line as usize + li
        } else {
            line as usize + li
        };
        let marker = if actual_line >= line as usize && actual_line <= end_line as usize {
            ">>>"
        } else {
            "   "
        };
        let numbered_line = actual_line + 1;
        println!("    {marker} {numbered_line:>4} | {l}");
    }
}

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

    #[test]
    fn snippet_deserializes_bare_string() {
        let json = r#""hello world""#;
        let s: Snippet = serde_json::from_str(json).unwrap();
        assert_eq!(s.as_str(), "hello world");
    }

    #[test]
    fn snippet_deserializes_object_form() {
        let json = r#"{"content": "hello world"}"#;
        let s: Snippet = serde_json::from_str(json).unwrap();
        assert_eq!(s.as_str(), "hello world");
    }

    #[test]
    fn snippet_deserializes_empty_string_bare() {
        let json = r#""""#;
        let s: Snippet = serde_json::from_str(json).unwrap();
        assert!(s.as_str().is_empty());
    }

    #[test]
    fn snippet_deserializes_empty_object_content() {
        let json = r#"{"content": ""}"#;
        let s: Snippet = serde_json::from_str(json).unwrap();
        assert!(s.as_str().is_empty());
    }

    #[test]
    fn snippet_default_is_empty_string() {
        let s = Snippet::default();
        assert_eq!(s.as_str(), "");
    }

    #[test]
    fn snippet_rejects_unknown_shape() {
        // Number is neither a bare string nor an object with `content`.
        let json = "42";
        let result: Result<Snippet, _> = serde_json::from_str(json);
        assert!(result.is_err());
    }

    #[test]
    fn evidence_row_uses_defaults_for_missing_fields() {
        let row: EvidenceRow = serde_json::from_str("{}").unwrap();
        assert!(row.file.is_empty());
        assert_eq!(row.line, 0);
        assert_eq!(row.end_line, 0);
        assert!(row.snippet.as_str().is_empty());
        assert_eq!(row.snippet_start_line, 0);
    }

    #[test]
    fn evidence_row_parses_bare_snippet() {
        let json =
            r#"{"file": "src/main.rs", "line": 10, "end_line": 12, "snippet": "fn main() {}"}"#;
        let row: EvidenceRow = serde_json::from_str(json).unwrap();
        assert_eq!(row.file, "src/main.rs");
        assert_eq!(row.line, 10);
        assert_eq!(row.end_line, 12);
        assert_eq!(row.snippet.as_str(), "fn main() {}");
        assert_eq!(row.snippet_start_line, 0);
    }

    #[test]
    fn evidence_row_parses_object_snippet() {
        let json = r#"{
            "file": "src/lib.rs",
            "line": 5,
            "end_line": 7,
            "snippet": {"content": "pub fn foo() {}"},
            "snippet_start_line": 3
        }"#;
        let row: EvidenceRow = serde_json::from_str(json).unwrap();
        assert_eq!(row.file, "src/lib.rs");
        assert_eq!(row.line, 5);
        assert_eq!(row.end_line, 7);
        assert_eq!(row.snippet.as_str(), "pub fn foo() {}");
        assert_eq!(row.snippet_start_line, 3);
    }

    #[test]
    fn evidence_row_ignores_unknown_fields() {
        let json = r#"{"file": "x", "extra_field": 123, "snippet": "code"}"#;
        let row: EvidenceRow = serde_json::from_str(json).unwrap();
        assert_eq!(row.file, "x");
        assert_eq!(row.snippet.as_str(), "code");
    }

    #[test]
    fn ext_data_default_has_no_evidence() {
        let ext = ExtData::default();
        assert!(ext.evidence.is_empty());
    }

    #[test]
    fn ext_data_parses_empty_object() {
        let ext: ExtData = serde_json::from_str("{}").unwrap();
        assert!(ext.evidence.is_empty());
    }

    #[test]
    fn ext_data_parses_evidence_array_mixed_shapes() {
        let json = r#"{
            "evidence": [
                {"file": "a.rs", "line": 1, "snippet": "x"},
                {"file": "b.rs", "line": 2, "snippet": {"content": "y"}}
            ],
            "other_field": "ignored"
        }"#;
        let ext: ExtData = serde_json::from_str(json).unwrap();
        assert_eq!(ext.evidence.len(), 2);
        assert_eq!(ext.evidence[0].file, "a.rs");
        assert_eq!(ext.evidence[0].snippet.as_str(), "x");
        assert_eq!(ext.evidence[1].file, "b.rs");
        assert_eq!(ext.evidence[1].snippet.as_str(), "y");
    }

    #[test]
    fn run_debug_returns_error_on_missing_database() {
        let dir = tempfile::tempdir().unwrap();
        let missing = dir.path().join("does-not-exist").join("nope.db");

        let result = run_debug(&missing, "main");
        assert!(result.is_err());
        let msg = result.unwrap_err().to_string();
        assert!(
            msg.contains("debug") || msg.contains("database") || msg.contains("failed"),
            "unexpected error: {msg}"
        );
    }

    #[test]
    fn run_debug_on_empty_db_succeeds_with_no_rows() {
        let dir = tempfile::tempdir().unwrap();
        let db_path = dir.path().join("empty.db");
        let conn = rusqlite::Connection::open(&db_path).unwrap();
        // Minimal schema mirroring the columns the debug query expects.
        conn.execute_batch(
            "CREATE TABLE nodes (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                branch_id TEXT NOT NULL,
                nature TEXT NOT NULL,
                weight TEXT NOT NULL,
                confidence REAL NOT NULL,
                adoption_count INTEGER NOT NULL,
                total_count INTEGER NOT NULL,
                description TEXT NOT NULL,
                ext_data TEXT
            );",
        )
        .unwrap();
        drop(conn);

        let result = run_debug(&db_path, "main");
        assert!(result.is_ok(), "got error: {:?}", result.err());
    }

    #[test]
    fn run_debug_walks_convention_rows_and_skips_user_source() {
        let dir = tempfile::tempdir().unwrap();
        let db_path = dir.path().join("seeded.db");
        let conn = rusqlite::Connection::open(&db_path).unwrap();
        conn.execute_batch(
            "CREATE TABLE nodes (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                branch_id TEXT NOT NULL,
                nature TEXT NOT NULL,
                weight TEXT NOT NULL,
                confidence REAL NOT NULL,
                adoption_count INTEGER NOT NULL,
                total_count INTEGER NOT NULL,
                description TEXT NOT NULL,
                ext_data TEXT
            );",
        )
        .unwrap();

        // Auto-detected convention with both snippet shapes in evidence.
        conn.execute(
            "INSERT INTO nodes (branch_id, nature, weight, confidence,
                adoption_count, total_count, description, ext_data)
             VALUES ('main', 'convention', 'strong', 0.9, 8, 10, 'C1', ?1)",
            rusqlite::params![
                serde_json::json!({
                    "evidence": [
                        {"file": "a.rs", "line": 1, "snippet": "code"},
                        {"file": "b.rs", "line": 2, "snippet": {"content": "more"}}
                    ]
                })
                .to_string()
            ],
        )
        .unwrap();

        // User-recorded decision — must be filtered out by run_debug's WHERE clause.
        conn.execute(
            "INSERT INTO nodes (branch_id, nature, weight, confidence,
                adoption_count, total_count, description, ext_data)
             VALUES ('main', 'convention', 'strong', 0.7, 0, 0, 'user-rec', ?1)",
            rusqlite::params![serde_json::json!({"source": "user"}).to_string()],
        )
        .unwrap();

        // Convention with malformed ext_data — must not crash the dump.
        conn.execute(
            "INSERT INTO nodes (branch_id, nature, weight, confidence,
                adoption_count, total_count, description, ext_data)
             VALUES ('main', 'convention', 'moderate', 0.5, 1, 1, 'malformed', ?1)",
            rusqlite::params!["{not valid json"],
        )
        .unwrap();

        // Different branch — must be filtered out.
        conn.execute(
            "INSERT INTO nodes (branch_id, nature, weight, confidence,
                adoption_count, total_count, description, ext_data)
             VALUES ('other', 'convention', 'strong', 0.6, 2, 2, 'other-branch', NULL)",
            [],
        )
        .unwrap();

        // Non-convention nature — also filtered out.
        conn.execute(
            "INSERT INTO nodes (branch_id, nature, weight, confidence,
                adoption_count, total_count, description, ext_data)
             VALUES ('main', 'fact', 'moderate', 0.5, 1, 1, 'fact-row', NULL)",
            [],
        )
        .unwrap();
        drop(conn);

        let result = run_debug(&db_path, "main");
        assert!(result.is_ok(), "got error: {:?}", result.err());
    }
}