ryo-app 0.1.0

//! Verification layer for spec-based testing
//!
//! Provides verification points that can be checked after each phase.

use thiserror::Error;

use super::types::VerificationPointSpec;

/// Verification error
#[derive(Debug, Clone, Error)]
pub enum VerificationError {
    #[error("Module not found: {0}")]
    ModuleNotFound(String),

    #[error("Type not found: {0}")]
    TypeNotFound(String),

    #[error("Missing derive on {ty}: {derive}")]
    MissingDerive { ty: String, derive: String },

    #[error("Missing field on {ty}: {field}")]
    MissingField { ty: String, field: String },

    #[error("Method not found: {ty}::{method}")]
    MethodNotFound { ty: String, method: String },

    #[error("Compilation failed: {0}")]
    CompilationFailed(String),

    #[error("Warning detected: {0}")]
    WarningDetected(String),
}

/// Verification point abstraction
#[derive(Debug, Clone)]
pub enum VerificationPoint {
    /// Check that a module exists
    ModuleExists(Vec<String>),

    /// Check that types exist
    TypeExists(Vec<String>),

    /// Check that a type has specific derives
    HasDerive { ty: String, derives: Vec<String> },

    /// Check that a struct has a specific field
    HasField {
        ty: String,
        field: String,
        field_type: String,
    },

    /// Check that a type has a specific method
    MethodExists { ty: String, method: String },

    /// Check that code compiles
    Compiles,

    /// Check for no warnings (with allowed list)
    NoWarnings { allowed: Vec<String> },
}

impl From<VerificationPointSpec> for VerificationPoint {
    fn from(spec: VerificationPointSpec) -> Self {
        match spec {
            VerificationPointSpec::ModuleExists { paths } => VerificationPoint::ModuleExists(paths),
            VerificationPointSpec::TypeExists { types } => VerificationPoint::TypeExists(types),
            VerificationPointSpec::HasDerive { ty, derives } => {
                VerificationPoint::HasDerive { ty, derives }
            }
            VerificationPointSpec::HasField {
                ty,
                field,
                field_type,
            } => VerificationPoint::HasField {
                ty,
                field,
                field_type,
            },
            VerificationPointSpec::MethodExists { ty, method } => {
                VerificationPoint::MethodExists { ty, method }
            }
            VerificationPointSpec::Compiles => VerificationPoint::Compiles,
            VerificationPointSpec::NoWarnings { allowed } => {
                VerificationPoint::NoWarnings { allowed }
            }
        }
    }
}

/// Result of running a verification
#[derive(Debug, Clone)]
pub struct VerificationResult {
    /// Phase name
    pub phase: String,

    /// Total points checked
    pub total: usize,

    /// Passed points
    pub passed: usize,

    /// Failed points with errors
    pub failures: Vec<(VerificationPoint, VerificationError)>,
}

impl VerificationResult {
    /// Check if all verifications passed
    pub fn all_passed(&self) -> bool {
        self.failures.is_empty()
    }
}

/// Verification runner
pub struct VerificationRunner {
    /// Project root path
    project_root: std::path::PathBuf,
}

impl VerificationRunner {
    /// Create a new verification runner
    pub fn new(project_root: impl Into<std::path::PathBuf>) -> Self {
        Self {
            project_root: project_root.into(),
        }
    }

    /// Run verifications for a phase
    pub fn run(&self, phase: &str, points: &[VerificationPoint]) -> VerificationResult {
        let mut passed = 0;
        let mut failures = Vec::new();

        for point in points {
            match self.verify_point(point) {
                Ok(()) => passed += 1,
                Err(e) => failures.push((point.clone(), e)),
            }
        }

        VerificationResult {
            phase: phase.to_string(),
            total: points.len(),
            passed,
            failures,
        }
    }

    /// Verify a single point
    fn verify_point(&self, point: &VerificationPoint) -> Result<(), VerificationError> {
        match point {
            VerificationPoint::ModuleExists(paths) => {
                for path in paths {
                    self.check_module_exists(path)?;
                }
                Ok(())
            }
            VerificationPoint::TypeExists(types) => {
                for ty in types {
                    self.check_type_exists(ty)?;
                }
                Ok(())
            }
            VerificationPoint::HasDerive { ty, derives } => {
                for derive in derives {
                    self.check_has_derive(ty, derive)?;
                }
                Ok(())
            }
            VerificationPoint::HasField {
                ty,
                field,
                field_type,
            } => self.check_has_field(ty, field, field_type),
            VerificationPoint::MethodExists { ty, method } => self.check_method_exists(ty, method),
            VerificationPoint::Compiles => self.check_compiles(),
            VerificationPoint::NoWarnings { allowed } => self.check_no_warnings(allowed),
        }
    }

    /// Check if a module exists
    fn check_module_exists(&self, path: &str) -> Result<(), VerificationError> {
        // Convert module path to file path
        let file_path = if path.contains("::") {
            let parts: Vec<&str> = path.split("::").collect();
            format!("src/{}.rs", parts.join("/"))
        } else {
            format!("src/{}.rs", path)
        };

        let full_path = self.project_root.join(&file_path);

        // Also check for mod.rs pattern
        let mod_path = if path.contains("::") {
            let parts: Vec<&str> = path.split("::").collect();
            format!("src/{}/mod.rs", parts.join("/"))
        } else {
            format!("src/{}/mod.rs", path)
        };

        let full_mod_path = self.project_root.join(&mod_path);

        if full_path.exists() || full_mod_path.exists() {
            Ok(())
        } else {
            Err(VerificationError::ModuleNotFound(path.to_string()))
        }
    }

    /// Check if a type exists (basic file-based check)
    fn check_type_exists(&self, ty: &str) -> Result<(), VerificationError> {
        // This would use ryo-analysis in a full implementation
        // For now, we just check that the type name appears in the source
        let src_path = self.project_root.join("src");

        if !src_path.exists() {
            return Err(VerificationError::TypeNotFound(ty.to_string()));
        }

        // Simple grep for the type definition
        // In production, use SymbolRegistry
        for entry in walkdir::WalkDir::new(&src_path)
            .into_iter()
            .filter_map(|e| e.ok())
            .filter(|e| e.path().extension().is_some_and(|ext| ext == "rs"))
        {
            if let Ok(content) = std::fs::read_to_string(entry.path()) {
                // Check for struct or enum definition
                let patterns = [
                    format!("struct {} ", ty),
                    format!("struct {}(", ty),
                    format!("struct {} {{", ty),
                    format!("enum {} ", ty),
                    format!("enum {} {{", ty),
                ];

                for pattern in &patterns {
                    if content.contains(pattern) {
                        return Ok(());
                    }
                }
            }
        }

        Err(VerificationError::TypeNotFound(ty.to_string()))
    }

    /// Check if a type has a derive
    fn check_has_derive(&self, ty: &str, derive: &str) -> Result<(), VerificationError> {
        // Would use ryo-analysis in full implementation
        let src_path = self.project_root.join("src");

        for entry in walkdir::WalkDir::new(&src_path)
            .into_iter()
            .filter_map(|e| e.ok())
            .filter(|e| e.path().extension().is_some_and(|ext| ext == "rs"))
        {
            if let Ok(content) = std::fs::read_to_string(entry.path()) {
                // Find type definition and check preceding derive
                if let Some(pos) = content.find(&format!("struct {}", ty)) {
                    let before = &content[..pos];
                    if let Some(derive_pos) = before.rfind("#[derive(") {
                        let derive_block = &before[derive_pos..];
                        if derive_block.contains(derive) {
                            return Ok(());
                        }
                    }
                }

                if let Some(pos) = content.find(&format!("enum {}", ty)) {
                    let before = &content[..pos];
                    if let Some(derive_pos) = before.rfind("#[derive(") {
                        let derive_block = &before[derive_pos..];
                        if derive_block.contains(derive) {
                            return Ok(());
                        }
                    }
                }
            }
        }

        Err(VerificationError::MissingDerive {
            ty: ty.to_string(),
            derive: derive.to_string(),
        })
    }

    /// Check if a struct has a field
    fn check_has_field(
        &self,
        ty: &str,
        field: &str,
        _field_type: &str,
    ) -> Result<(), VerificationError> {
        // Would use ryo-analysis in full implementation
        let src_path = self.project_root.join("src");

        for entry in walkdir::WalkDir::new(&src_path)
            .into_iter()
            .filter_map(|e| e.ok())
            .filter(|e| e.path().extension().is_some_and(|ext| ext == "rs"))
        {
            if let Ok(content) = std::fs::read_to_string(entry.path()) {
                // Find struct definition
                if let Some(pos) = content.find(&format!("struct {} {{", ty)) {
                    // Find the closing brace
                    if let Some(end) = content[pos..].find('}') {
                        let struct_body = &content[pos..pos + end];
                        if struct_body.contains(&field.to_string()) {
                            return Ok(());
                        }
                    }
                }
            }
        }

        Err(VerificationError::MissingField {
            ty: ty.to_string(),
            field: field.to_string(),
        })
    }

    /// Check if a type has a method
    fn check_method_exists(&self, ty: &str, method: &str) -> Result<(), VerificationError> {
        // Would use ryo-analysis in full implementation
        let src_path = self.project_root.join("src");

        for entry in walkdir::WalkDir::new(&src_path)
            .into_iter()
            .filter_map(|e| e.ok())
            .filter(|e| e.path().extension().is_some_and(|ext| ext == "rs"))
        {
            if let Ok(content) = std::fs::read_to_string(entry.path()) {
                // Find impl block for the type
                if content.contains(&format!("impl {}", ty))
                    && content.contains(&format!("fn {}(", method))
                {
                    return Ok(());
                }
            }
        }

        Err(VerificationError::MethodNotFound {
            ty: ty.to_string(),
            method: method.to_string(),
        })
    }

    /// Check that code compiles
    fn check_compiles(&self) -> Result<(), VerificationError> {
        let output = std::process::Command::new("cargo")
            .arg("check")
            .current_dir(&self.project_root)
            .output();

        match output {
            Ok(out) if out.status.success() => Ok(()),
            Ok(out) => {
                let stderr = String::from_utf8_lossy(&out.stderr);
                Err(VerificationError::CompilationFailed(stderr.to_string()))
            }
            Err(e) => Err(VerificationError::CompilationFailed(e.to_string())),
        }
    }

    /// Check for no warnings
    fn check_no_warnings(&self, allowed: &[String]) -> Result<(), VerificationError> {
        let output = std::process::Command::new("cargo")
            .args(["check", "--message-format=short"])
            .current_dir(&self.project_root)
            .output();

        match output {
            Ok(out) => {
                let stderr = String::from_utf8_lossy(&out.stderr);

                // Filter out allowed warnings
                for line in stderr.lines() {
                    if line.contains("warning:") {
                        let is_allowed = allowed.iter().any(|a| line.contains(a));
                        if !is_allowed {
                            return Err(VerificationError::WarningDetected(line.to_string()));
                        }
                    }
                }

                Ok(())
            }
            Err(e) => Err(VerificationError::CompilationFailed(e.to_string())),
        }
    }
}

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

    #[test]
    fn test_verification_result() {
        let result = VerificationResult {
            phase: "test".to_string(),
            total: 3,
            passed: 3,
            failures: vec![],
        };

        assert!(result.all_passed());
    }

    #[test]
    fn test_verification_point_from_spec() {
        let spec = VerificationPointSpec::ModuleExists {
            paths: vec!["user".to_string(), "product".to_string()],
        };

        let point: VerificationPoint = spec.into();

        if let VerificationPoint::ModuleExists(paths) = point {
            assert_eq!(paths.len(), 2);
        } else {
            panic!("Expected ModuleExists");
        }
    }
}