ggen-core 26.7.2

//! Manifest validation module
//!
//! Validates parsed manifests for semantic correctness beyond TOML parsing.

use crate::manifest::types::{GgenManifest, QuerySource, TemplateSource};
use crate::utils::error::{Error, Result};
use std::path::Path;

/// Validator for ggen.toml manifests
pub struct ManifestValidator<'a> {
    manifest: &'a GgenManifest,
    base_path: &'a Path,
}

impl<'a> ManifestValidator<'a> {
    /// Create a new validator for the given manifest
    ///
    /// # Arguments
    /// * `manifest` - The parsed manifest to validate
    /// * `base_path` - Base path for resolving relative file paths
    pub fn new(manifest: &'a GgenManifest, base_path: &'a Path) -> Self {
        Self {
            manifest,
            base_path,
        }
    }

    /// Run all validations
    ///
    /// # Returns
    /// * `Ok(())` - All validations passed
    /// * `Err(Error)` - First validation failure
    pub fn validate(&self) -> Result<()> {
        self.validate_project()?;
        self.validate_ontology()?;
        self.validate_inference_rules()?;
        self.validate_generation_rules()?;
        self.validate_shacl_paths()?;
        Ok(())
    }

    /// Validate project section
    fn validate_project(&self) -> Result<()> {
        if self.manifest.project.name.is_empty() {
            return Err(Error::new("project.name cannot be empty"));
        }
        if self.manifest.project.version.is_empty() {
            return Err(Error::new("project.version cannot be empty"));
        }
        Ok(())
    }

    /// Validate ontology configuration
    fn validate_ontology(&self) -> Result<()> {
        let source_path = self.base_path.join(&self.manifest.ontology.source);
        if !source_path.exists() {
            return Err(Error::new(&format!(
                "Ontology source not found: {}",
                source_path.display()
            )));
        }

        // Validate imports exist
        for import in &self.manifest.ontology.imports {
            let import_path = self.base_path.join(import);
            if !import_path.exists() {
                return Err(Error::new(&format!(
                    "Ontology import not found: {}",
                    import_path.display()
                )));
            }
        }

        Ok(())
    }

    /// Validate inference rules
    fn validate_inference_rules(&self) -> Result<()> {
        let mut seen_orders: Vec<i32> = Vec::new();

        for rule in &self.manifest.inference.rules {
            if rule.name.is_empty() {
                return Err(Error::new("inference.rules[].name cannot be empty"));
            }
            if rule.construct.is_empty() {
                return Err(Error::new(&format!(
                    "inference.rules[{}].construct cannot be empty",
                    rule.name
                )));
            }

            // Check for ORDER BY in CONSTRUCT (determinism guard)
            let construct_upper = rule.construct.to_uppercase();
            if !construct_upper.contains("ORDER BY") {
                if self.manifest.validation.strict_mode {
                    return Err(Error::new(&format!(
                        "error[E0011]: Inference rule '{}' CONSTRUCT query lacks ORDER BY\n  |\n  = strict_mode is enabled: non-deterministic triple ordering is rejected\n  = help: Add ORDER BY to your CONSTRUCT query to guarantee deterministic output\n  = help: Or set `strict_mode = false` in [validation] to downgrade to a warning",
                        rule.name
                    )));
                }
                log::warn!(
                    "Inference rule '{}' CONSTRUCT query lacks ORDER BY - may produce non-deterministic results",
                    rule.name
                );
            }

            // Check for duplicate order values (not an error, just tracked)
            if seen_orders.contains(&rule.order) {
                log::warn!(
                    "Inference rule '{}' has duplicate order value {}",
                    rule.name,
                    rule.order
                );
            }
            seen_orders.push(rule.order);
        }

        Ok(())
    }

    /// Validate generation rules
    fn validate_generation_rules(&self) -> Result<()> {
        for rule in &self.manifest.generation.rules {
            if rule.name.is_empty() {
                return Err(Error::new("generation.rules[].name cannot be empty"));
            }

            // Validate query source exists and does not contain VALUES clauses
            // VALUES data must live inline in ggen.toml — never in external .rq files
            if let QuerySource::File { file } = &rule.query {
                let query_path = self.base_path.join(file);
                if !query_path.exists() {
                    return Err(Error::new(&format!(
                        "Query file not found for rule '{}': {}",
                        rule.name,
                        query_path.display()
                    )));
                }
                let content = std::fs::read_to_string(&query_path).map_err(|e| {
                    Error::new(&format!(
                        "Failed to read query file for rule '{}': {}",
                        rule.name, e
                    ))
                })?;
                if query_contains_values(&content) {
                    return Err(Error::new(&format!(
                        "error[E0010]: VALUES data must be inline in ggen.toml\n  --> rule: '{}'\n  --> file: {}\n  |\n  = VALUES clauses belong in ggen.toml as `query = {{ inline = \"SELECT ... WHERE {{ VALUES ... }}\" }}`\n  = External .rq files are for queries against real RDF triples only\n  = help: Move the VALUES block into ggen.toml and delete the .rq file",
                        rule.name,
                        query_path.display()
                    )));
                }
            }

            // Validate template source exists
            if let TemplateSource::File { file } = &rule.template {
                let template_path = self.base_path.join(file);
                if !template_path.exists() {
                    return Err(Error::new(&format!(
                        "Template file not found for rule '{}': {}",
                        rule.name,
                        template_path.display()
                    )));
                }
            }

            // E0014: Check that any pack referenced in a QuerySource::Pack or
            // TemplateSource::Pack rule is declared in [[packs]].
            let rule_pack_name: Option<&str> = match &rule.query {
                QuerySource::Pack { pack, .. } => Some(pack.as_str()),
                _ => match &rule.template {
                    crate::manifest::TemplateSource::Pack { pack, .. } => Some(pack.as_str()),
                    _ => None,
                },
            };
            if let Some(pack_name) = rule_pack_name {
                if !self.manifest.packs.iter().any(|p| p.name == pack_name) {
                    return Err(Error::new(&format!(
                        "error[E0014]: Pack '{}' used in rule '{}' is not declared in [[packs]]",
                        pack_name, rule.name
                    )));
                }
            }

            // E0013: Check for ORDER BY in SELECT queries (determinism guard).
            // Mirrors E0011 for CONSTRUCT. Pack queries are resolved at runtime
            // and not available here — skip them.
            let query_text_opt: Option<String> = match &rule.query {
                QuerySource::Inline { inline } => Some(inline.clone()),
                QuerySource::File { file } => {
                    let qpath = self.base_path.join(file);
                    std::fs::read_to_string(&qpath).ok()
                }
                QuerySource::Pack { .. } => None, // resolved at sync time; skip
            };
            if let Some(ref query_text) = query_text_opt {
                if !query_has_order_by(query_text) {
                    if self.manifest.validation.strict_mode {
                        return Err(Error::new(&format!(
                            "error[E0013]: Generation rule '{}' SELECT query lacks ORDER BY\n  |\n  = strict_mode is enabled: non-deterministic row ordering is rejected\n  = help: Add ORDER BY to your SELECT query to guarantee deterministic template rendering\n  = help: Or set `strict_mode = false` in [validation] to downgrade to a warning",
                            rule.name
                        )));
                    }
                    log::warn!(
                        "Generation rule '{}' SELECT query lacks ORDER BY — row order may vary across runs",
                        rule.name
                    );
                }
            }

            // Validate output path pattern
            if rule.output_file.is_empty() {
                return Err(Error::new(&format!(
                    "generation.rules[{}].output_file cannot be empty",
                    rule.name
                )));
            }
        }

        Ok(())
    }

    /// Validate SHACL shape file paths
    fn validate_shacl_paths(&self) -> Result<()> {
        for shacl_path in &self.manifest.validation.shacl {
            let full_path = self.base_path.join(shacl_path);
            if !full_path.exists() {
                return Err(Error::new(&format!(
                    "SHACL shape file not found: {}",
                    full_path.display()
                )));
            }
        }
        Ok(())
    }
}

/// Returns true if the SPARQL string contains an ORDER BY clause.
///
/// Detection is case-insensitive and covers multiline queries. This is a
/// textual heuristic (oxigraph does not expose an AST); "ORDER BY" in a
/// SPARQL comment or string literal would be a false-positive, but that
/// edge case is acceptable — it only suppresses a warning, not correctness.
pub fn query_has_order_by(sparql: &str) -> bool {
    sparql.to_uppercase().contains("ORDER BY")
}

/// Returns true if the SPARQL query string contains a VALUES clause.
/// Strips `#`-prefixed line comments before checking so commented-out
/// VALUES blocks do not trigger the guard.
pub fn query_contains_values(query: &str) -> bool {
    query
        .lines()
        .filter(|line| !line.trim_start().starts_with('#'))
        .any(|line| {
            line.split_whitespace()
                .any(|tok| tok.eq_ignore_ascii_case("VALUES"))
        })
}

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

    fn create_test_manifest() -> GgenManifest {
        let toml = r#"
[project]
name = "test"
version = "1.0.0"

[ontology]
source = "Cargo.toml"  # Use existing file for test

[generation]
rules = []
"#;
        ManifestParser::parse_str(toml).unwrap()
    }

    #[test]
    fn test_validate_empty_project_name() {
        let toml = r#"
[project]
name = ""
version = "1.0.0"

[ontology]
source = "test.ttl"

[generation]
rules = []
"#;
        let manifest = ManifestParser::parse_str(toml).unwrap();
        let validator = ManifestValidator::new(&manifest, Path::new("."));
        assert!(validator.validate().is_err());
    }

    #[test]
    fn test_validate_missing_ontology() {
        let manifest = create_test_manifest();
        // Use a path where the ontology won't exist
        let validator = ManifestValidator::new(&manifest, Path::new("/nonexistent/path"));
        assert!(validator.validate().is_err());
    }
}