asupersync/cli/

error.rs

//! Structured error messages for CLI tools.
//!
//! Follows RFC 9457 (Problem Details) style for machine-readable errors
//! with human-friendly formatting.

use super::exit::ExitCode;
use serde::{Deserialize, Serialize};
use std::collections::HashMap;

/// Structured error following RFC 9457 (Problem Details) style.
///
/// Provides machine-readable error information with human-friendly presentation.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CliError {
    /// Error type identifier (machine-readable).
    #[serde(rename = "type")]
    pub error_type: String,

    /// Short human-readable title.
    pub title: String,

    /// Detailed explanation.
    #[serde(default, skip_serializing_if = "String::is_empty")]
    pub detail: String,

    /// Suggested action for recovery.
    #[serde(skip_serializing_if = "Option::is_none")]
    pub suggestion: Option<String>,

    /// Related documentation URL.
    #[serde(skip_serializing_if = "Option::is_none")]
    pub docs_url: Option<String>,

    /// Additional context (varies by error type).
    #[serde(default, skip_serializing_if = "HashMap::is_empty")]
    pub context: HashMap<String, serde_json::Value>,

    /// Exit code for this error.
    pub exit_code: i32,
}

impl CliError {
    /// Create a new CLI error.
    #[must_use]
    pub fn new(error_type: impl Into<String>, title: impl Into<String>) -> Self {
        Self {
            error_type: error_type.into(),
            title: title.into(),
            detail: String::new(),
            suggestion: None,
            docs_url: None,
            context: HashMap::new(),
            exit_code: ExitCode::RUNTIME_ERROR,
        }
    }

    /// Add detailed explanation.
    #[must_use]
    pub fn detail(mut self, detail: impl Into<String>) -> Self {
        self.detail = detail.into();
        self
    }

    /// Add a suggested recovery action.
    #[must_use]
    pub fn suggestion(mut self, suggestion: impl Into<String>) -> Self {
        self.suggestion = Some(suggestion.into());
        self
    }

    /// Add documentation URL.
    #[must_use]
    pub fn docs(mut self, url: impl Into<String>) -> Self {
        self.docs_url = Some(url.into());
        self
    }

    /// Add context field.
    #[must_use]
    pub fn context(mut self, key: impl Into<String>, value: impl Serialize) -> Self {
        if let Ok(v) = serde_json::to_value(value) {
            self.context.insert(key.into(), v);
        }
        self
    }

    /// Set exit code.
    #[must_use]
    pub const fn exit_code(mut self, code: i32) -> Self {
        self.exit_code = code;
        self
    }

    /// Format for human output.
    ///
    /// When `color` is true, includes ANSI escape codes for terminal coloring.
    #[must_use]
    pub fn human_format(&self, color: bool) -> String {
        let mut out = String::new();

        // Error title in red
        if color {
            out.push_str("\x1b[1;31m"); // Bold red
        }
        out.push_str("Error: ");
        out.push_str(&self.title);
        if color {
            out.push_str("\x1b[0m"); // Reset
        }
        out.push('\n');

        // Detail in normal text
        if !self.detail.is_empty() {
            out.push_str(&self.detail);
            out.push('\n');
        }

        // Suggestion in yellow
        if let Some(ref suggestion) = self.suggestion {
            out.push('\n');
            if color {
                out.push_str("\x1b[33m"); // Yellow
            }
            out.push_str("Suggestion: ");
            out.push_str(suggestion);
            if color {
                out.push_str("\x1b[0m");
            }
            out.push('\n');
        }

        // Docs link in blue/underline
        if let Some(ref docs) = self.docs_url {
            if color {
                out.push_str("\x1b[4;34m"); // Underline blue
            }
            out.push_str("See: ");
            out.push_str(docs);
            if color {
                out.push_str("\x1b[0m");
            }
            out.push('\n');
        }

        // Context in dim
        if !self.context.is_empty() {
            out.push('\n');
            if color {
                out.push_str("\x1b[2m"); // Dim
            }
            out.push_str("Context:\n");
            for (k, v) in &self.context {
                use std::fmt::Write;
                let _ = writeln!(out, "  {k}: {v}");
            }
            if color {
                out.push_str("\x1b[0m");
            }
        }

        out
    }

    /// Format as JSON.
    #[must_use]
    pub fn json_format(&self) -> String {
        serde_json::to_string(self).unwrap_or_else(|_| self.title.clone())
    }

    /// Format as pretty JSON.
    #[must_use]
    pub fn json_pretty_format(&self) -> String {
        serde_json::to_string_pretty(self).unwrap_or_else(|_| self.title.clone())
    }
}

impl std::fmt::Display for CliError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}: {}", self.error_type, self.title)
    }
}

impl std::error::Error for CliError {}

/// Standard error constructors.
pub mod errors {
    use super::{CliError, ExitCode};

    /// Invalid argument error.
    #[must_use]
    pub fn invalid_argument(arg: &str, reason: &str) -> CliError {
        CliError::new("invalid_argument", format!("Invalid argument: {arg}"))
            .detail(reason)
            .exit_code(ExitCode::USER_ERROR)
    }

    /// File not found error.
    #[must_use]
    pub fn file_not_found(path: &str) -> CliError {
        CliError::new("file_not_found", "File not found")
            .detail(format!("The file '{path}' does not exist"))
            .suggestion("Check the path and try again")
            .context("path", path)
            .exit_code(ExitCode::USER_ERROR)
    }

    /// Permission denied error.
    #[must_use]
    pub fn permission_denied(path: &str) -> CliError {
        CliError::new("permission_denied", "Permission denied")
            .detail(format!("Cannot access '{path}'"))
            .suggestion("Check file permissions or run with appropriate privileges")
            .context("path", path)
            .exit_code(ExitCode::USER_ERROR)
    }

    /// Invariant violation error.
    #[must_use]
    pub fn invariant_violation(invariant: &str, details: &str) -> CliError {
        CliError::new(
            "invariant_violation",
            format!("Invariant violated: {invariant}"),
        )
        .detail(details)
        .docs("https://docs.asupersync.dev/invariants")
        .exit_code(ExitCode::RUNTIME_ERROR)
    }

    /// Parse error.
    #[must_use]
    pub fn parse_error(what: &str, details: &str) -> CliError {
        CliError::new("parse_error", format!("Failed to parse {what}"))
            .detail(details)
            .exit_code(ExitCode::USER_ERROR)
    }

    /// Operation cancelled error.
    #[must_use]
    pub fn cancelled() -> CliError {
        CliError::new("cancelled", "Operation cancelled")
            .detail("The operation was cancelled by user or signal")
            .exit_code(ExitCode::CANCELLED)
    }

    /// Timeout error.
    #[must_use]
    pub fn timeout(operation: &str, duration_ms: u64) -> CliError {
        CliError::new("timeout", format!("Operation timed out: {operation}"))
            .detail(format!("Exceeded timeout after {duration_ms}ms"))
            .context("duration_ms", duration_ms)
            .exit_code(ExitCode::RUNTIME_ERROR)
    }

    /// Internal error (bug).
    #[must_use]
    pub fn internal(details: &str) -> CliError {
        CliError::new("internal_error", "Internal error")
            .detail(details)
            .suggestion(
                "Please report this bug at https://github.com/Dicklesworthstone/asupersync/issues",
            )
            .exit_code(ExitCode::INTERNAL_ERROR)
    }

    /// Test failure error.
    #[must_use]
    pub fn test_failure(test_name: &str, reason: &str) -> CliError {
        CliError::new("test_failure", format!("Test failed: {test_name}"))
            .detail(reason)
            .context("test_name", test_name)
            .exit_code(ExitCode::TEST_FAILURE)
    }

    /// Oracle violation error.
    #[must_use]
    pub fn oracle_violation(oracle: &str, details: &str) -> CliError {
        CliError::new("oracle_violation", format!("Oracle violation: {oracle}"))
            .detail(details)
            .context("oracle", oracle)
            .exit_code(ExitCode::ORACLE_VIOLATION)
    }
}

#[cfg(test)]
mod tests {
    use super::{errors, CliError, ExitCode};

    fn init_test(name: &str) {
        crate::test_utils::init_test_logging();
        crate::test_phase!(name);
    }

    #[test]
    fn error_serializes_to_json() {
        init_test("error_serializes_to_json");
        let error = CliError::new("test_error", "Test Error")
            .detail("Something went wrong")
            .suggestion("Try again")
            .context("file", "test.rs")
            .exit_code(1);

        let json = serde_json::to_string(&error).unwrap();
        let parsed: serde_json::Value = serde_json::from_str(&json).unwrap();

        crate::assert_with_log!(
            parsed["type"] == "test_error",
            "type",
            "test_error",
            parsed["type"].clone()
        );
        crate::assert_with_log!(
            parsed["title"] == "Test Error",
            "title",
            "Test Error",
            parsed["title"].clone()
        );
        crate::assert_with_log!(
            parsed["detail"] == "Something went wrong",
            "detail",
            "Something went wrong",
            parsed["detail"].clone()
        );
        crate::assert_with_log!(
            parsed["suggestion"] == "Try again",
            "suggestion",
            "Try again",
            parsed["suggestion"].clone()
        );
        crate::assert_with_log!(
            parsed["context"]["file"] == "test.rs",
            "context file",
            "test.rs",
            parsed["context"]["file"].clone()
        );
        crate::assert_with_log!(
            parsed["exit_code"] == 1,
            "exit_code",
            1,
            parsed["exit_code"].clone()
        );
        crate::test_complete!("error_serializes_to_json");
    }

    #[test]
    fn error_human_format_includes_all_parts() {
        init_test("error_human_format_includes_all_parts");
        let error = CliError::new("test_error", "Test Error")
            .detail("Details here")
            .suggestion("Try this");

        let human = error.human_format(false);

        let has_title = human.contains("Error: Test Error");
        crate::assert_with_log!(has_title, "title", true, has_title);
        let has_details = human.contains("Details here");
        crate::assert_with_log!(has_details, "details", true, has_details);
        let has_suggestion = human.contains("Suggestion: Try this");
        crate::assert_with_log!(has_suggestion, "suggestion", true, has_suggestion);
        crate::test_complete!("error_human_format_includes_all_parts");
    }

    #[test]
    fn error_human_format_no_ansi_when_disabled() {
        init_test("error_human_format_no_ansi_when_disabled");
        let error = CliError::new("test", "Test");
        let human = error.human_format(false);

        let has_ansi = human.contains("\x1b[");
        crate::assert_with_log!(!has_ansi, "no ansi", false, has_ansi);
        crate::test_complete!("error_human_format_no_ansi_when_disabled");
    }

    #[test]
    fn error_human_format_has_ansi_when_enabled() {
        init_test("error_human_format_has_ansi_when_enabled");
        let error = CliError::new("test", "Test");
        let human = error.human_format(true);

        let has_ansi = human.contains("\x1b[");
        crate::assert_with_log!(has_ansi, "has ansi", true, has_ansi);
        crate::test_complete!("error_human_format_has_ansi_when_enabled");
    }

    #[test]
    fn error_implements_display() {
        init_test("error_implements_display");
        let error = CliError::new("test_type", "Test Title");
        let display = format!("{error}");

        let has_type = display.contains("test_type");
        crate::assert_with_log!(has_type, "type", true, has_type);
        let has_title = display.contains("Test Title");
        crate::assert_with_log!(has_title, "title", true, has_title);
        crate::test_complete!("error_implements_display");
    }

    #[test]
    fn standard_errors_have_correct_exit_codes() {
        init_test("standard_errors_have_correct_exit_codes");
        let invalid = errors::invalid_argument("foo", "bad").exit_code;
        crate::assert_with_log!(
            invalid == ExitCode::USER_ERROR,
            "invalid_argument",
            ExitCode::USER_ERROR,
            invalid
        );
        let not_found = errors::file_not_found("/path").exit_code;
        crate::assert_with_log!(
            not_found == ExitCode::USER_ERROR,
            "file_not_found",
            ExitCode::USER_ERROR,
            not_found
        );
        let permission = errors::permission_denied("/path").exit_code;
        crate::assert_with_log!(
            permission == ExitCode::USER_ERROR,
            "permission_denied",
            ExitCode::USER_ERROR,
            permission
        );
        let cancelled = errors::cancelled().exit_code;
        crate::assert_with_log!(
            cancelled == ExitCode::CANCELLED,
            "cancelled",
            ExitCode::CANCELLED,
            cancelled
        );
        let internal = errors::internal("bug").exit_code;
        crate::assert_with_log!(
            internal == ExitCode::INTERNAL_ERROR,
            "internal",
            ExitCode::INTERNAL_ERROR,
            internal
        );
        let test_failure = errors::test_failure("test", "reason").exit_code;
        crate::assert_with_log!(
            test_failure == ExitCode::TEST_FAILURE,
            "test_failure",
            ExitCode::TEST_FAILURE,
            test_failure
        );
        let oracle = errors::oracle_violation("oracle", "details").exit_code;
        crate::assert_with_log!(
            oracle == ExitCode::ORACLE_VIOLATION,
            "oracle_violation",
            ExitCode::ORACLE_VIOLATION,
            oracle
        );
        crate::test_complete!("standard_errors_have_correct_exit_codes");
    }

    #[test]
    fn error_context_accepts_various_types() {
        init_test("error_context_accepts_various_types");
        let error = CliError::new("test", "Test")
            .context("string", "value")
            .context("number", 42)
            .context("bool", true)
            .context("array", vec![1, 2, 3]);

        let len = error.context.len();
        crate::assert_with_log!(len == 4, "context len", 4, len);
        crate::assert_with_log!(
            error.context["string"] == "value",
            "string",
            "value",
            error.context["string"].clone()
        );
        crate::assert_with_log!(
            error.context["number"] == 42,
            "number",
            42,
            error.context["number"].clone()
        );
        crate::assert_with_log!(
            error.context["bool"] == true,
            "bool",
            true,
            error.context["bool"].clone()
        );
        crate::test_complete!("error_context_accepts_various_types");
    }

    #[test]
    fn error_deserializes_from_json() {
        init_test("error_deserializes_from_json");
        let json = r#"{"type":"test","title":"Test","exit_code":1}"#;
        let error: CliError = serde_json::from_str(json).unwrap();

        crate::assert_with_log!(error.error_type == "test", "type", "test", error.error_type);
        crate::assert_with_log!(error.title == "Test", "title", "Test", error.title);
        crate::assert_with_log!(error.exit_code == 1, "exit_code", 1, error.exit_code);
        crate::test_complete!("error_deserializes_from_json");
    }
}