openlatch-client 0.1.6

/// Error framework for OpenLatch client using the OL-XXXX code format.
///
/// All user-facing errors carry a structured code, message, optional suggestion,
/// and optional docs URL. The Display format follows the D-06/D-07 convention:
///
/// ```text
/// Error: {message} (OL-XXXX)
///
///   Suggestion: {actionable text}
///   Docs: {url}
/// ```
///
/// Suggestion and Docs lines are omitted when the respective field is `None`.
use std::fmt;

/// A structured, user-facing error with an OL-XXXX code.
///
/// # Display format (D-06/D-07)
///
/// ```text
/// Error: {message} (OL-XXXX)
///
///   Suggestion: {actionable text}
///   Docs: {url}
/// ```
#[derive(Debug, Clone)]
pub struct OlError {
    /// The OL-XXXX error code (e.g. "OL-1001").
    pub code: &'static str,
    /// Human-readable, actionable error description.
    pub message: String,
    /// Optional suggestion for how to fix the error.
    pub suggestion: Option<String>,
    /// Optional link to documentation for this error code.
    pub docs_url: Option<String>,
}

impl OlError {
    /// Create a new error with the given code and message.
    pub fn new(code: &'static str, message: impl Into<String>) -> Self {
        Self {
            code,
            message: message.into(),
            suggestion: None,
            docs_url: None,
        }
    }

    /// Attach a suggestion to this error.
    pub fn with_suggestion(mut self, s: impl Into<String>) -> Self {
        self.suggestion = Some(s.into());
        self
    }

    /// Attach a docs URL to this error.
    pub fn with_docs(mut self, url: impl Into<String>) -> Self {
        self.docs_url = Some(url.into());
        self
    }

    /// Build a "bug report" error pre-filled with a GitHub issue URL.
    ///
    /// Use this for unexpected internal errors that indicate a bug in openlatch.
    pub fn bug_report(message: impl Into<String>) -> Self {
        let msg = message.into();
        let url = format!(
            "https://github.com/OpenLatch/openlatch-client/issues/new?title={}&body={}",
            percent_encode(&msg),
            percent_encode("Version: [auto]\nOS: [auto]\n\nDescription:\n"),
        );
        Self {
            code: "OL-9999",
            message: msg,
            suggestion: Some("This is a bug. Please report it.".into()),
            docs_url: Some(url),
        }
    }
}

impl fmt::Display for OlError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "Error: {} ({})", self.message, self.code)?;

        let has_suggestion = self.suggestion.is_some();
        let has_docs = self.docs_url.is_some();

        if has_suggestion || has_docs {
            writeln!(f)?;
            writeln!(f)?;
            if let Some(ref s) = self.suggestion {
                writeln!(f, "  Suggestion: {s}")?;
            }
            if let Some(ref url) = self.docs_url {
                write!(f, "  Docs: {url}")?;
            }
        }

        Ok(())
    }
}

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

/// Minimal percent-encoding for URL query parameters.
///
/// Only encodes characters that break URL structure: space, newline, carriage return,
/// ampersand, equals sign, and the hash character. This avoids pulling in a
/// full URL-encoding dependency for a single use in bug_report().
fn percent_encode(input: &str) -> String {
    let mut out = String::with_capacity(input.len());
    for c in input.chars() {
        match c {
            ' ' => out.push_str("%20"),
            '\n' => out.push_str("%0A"),
            '\r' => out.push_str("%0D"),
            '&' => out.push_str("%26"),
            '=' => out.push_str("%3D"),
            '#' => out.push_str("%23"),
            other => out.push(other),
        }
    }
    out
}

// ---------------------------------------------------------------------------
// Envelope errors (OL-1000–1099)
// ---------------------------------------------------------------------------

// OL-1001 (ERR_UNKNOWN_AGENT) was retired with the CloudEvents v1.0.2
// migration — `source` and `type` are open strings surfaced through the
// tagged-enum lens (src/core/envelope/known_types.rs), so unknown values
// are a valid runtime path, not an error. The code is intentionally left
// vacant so it is never reused with different semantics. See
// .brainstorms/2026-04-16-forward-compatible-wire-enums.md §5.7.
/// Event body exceeds the 1 MB size limit.
pub const ERR_EVENT_TOO_LARGE: &str = "OL-1002";
/// Event was deduplicated within the TTL window (informational).
pub const ERR_EVENT_DEDUPED: &str = "OL-1003";

// ---------------------------------------------------------------------------
// Privacy filter errors (OL-1100–1199)
// ---------------------------------------------------------------------------

/// A custom regex pattern in config.toml failed to compile.
pub const ERR_INVALID_REGEX: &str = "OL-1100";

// ---------------------------------------------------------------------------
// Cloud forwarding errors (OL-1200–1299)
// ---------------------------------------------------------------------------

/// Cloud API endpoint is unreachable (network error or DNS failure).
pub const ERR_CLOUD_UNREACHABLE: &str = "OL-1200";
/// Cloud returned 401/403 — API key is invalid or revoked.
pub const ERR_CLOUD_AUTH_FAILED: &str = "OL-1201";
/// Cloud returned 429 — rate limit exceeded; respect Retry-After header.
pub const ERR_CLOUD_RATE_LIMITED: &str = "OL-1202";

// ---------------------------------------------------------------------------
// Config errors (OL-1300–1399)
// ---------------------------------------------------------------------------

/// The configuration file contains an invalid value.
pub const ERR_INVALID_CONFIG: &str = "OL-1300";
/// A required configuration field is absent and has no default.
pub const ERR_MISSING_CONFIG_FIELD: &str = "OL-1301";

// ---------------------------------------------------------------------------
// Hooks errors (OL-1400–OL-1499)
// ---------------------------------------------------------------------------

/// No supported AI agent was detected on this machine.
pub const ERR_HOOK_AGENT_NOT_FOUND: &str = "OL-1400";
/// Cannot read or write the agent's settings.json (permissions, I/O error).
pub const ERR_HOOK_WRITE_FAILED: &str = "OL-1401";
/// The settings.json file contains malformed JSONC that cannot be parsed.
pub const ERR_HOOK_MALFORMED_JSONC: &str = "OL-1402";
/// Existing non-OpenLatch hooks detected in settings.json (warning, non-blocking).
pub const ERR_HOOK_CONFLICT: &str = "OL-1403";

// ---------------------------------------------------------------------------
// Daemon errors (OL-1500–1599)
// ---------------------------------------------------------------------------

/// The selected port is already in use by another process.
pub const ERR_PORT_IN_USE: &str = "OL-1500";
/// A daemon instance is already running on this machine.
pub const ERR_ALREADY_RUNNING: &str = "OL-1501";
/// Daemon process started but health check failed within timeout.
pub const ERR_DAEMON_START_FAILED: &str = "OL-1502";
/// A newer version of openlatch is available (warning, non-blocking).
pub const ERR_VERSION_OUTDATED: &str = "OL-1503";

// ---------------------------------------------------------------------------
// Auth / credential errors (OL-1600–1699)
// ---------------------------------------------------------------------------

/// No credentials found in keychain, env var, or encrypted file.
pub const ERR_NO_CREDENTIALS: &str = "OL-1600";
/// API key / token has expired or been revoked.
pub const ERR_TOKEN_EXPIRED: &str = "OL-1601";
/// OS keychain service is unavailable (e.g., no Secret Service on headless Linux).
pub const ERR_KEYCHAIN_UNAVAILABLE: &str = "OL-1602";
/// OS keychain denied access (permission error).
pub const ERR_KEYCHAIN_PERMISSION: &str = "OL-1603";
/// Encrypted file fallback failed (decrypt error, missing file, or corrupt data).
pub const ERR_FILE_FALLBACK_ERROR: &str = "OL-1604";
/// Auth login flow timed out after 5 minutes waiting for browser callback.
pub const ERR_AUTH_TIMEOUT: &str = "OL-1605";
/// Auth login flow failed (callback server error, truncated request, browser launch error).
pub const ERR_AUTH_FLOW_FAILED: &str = "OL-1606";
/// Server-side API key revocation failed during logout (warning only — local cleanup continues).
pub const ERR_AUTH_REVOCATION_FAILED: &str = "OL-1607";

/// Returns a platform-specific suggestion for keychain errors (D-23).
///
/// Provides actionable guidance tailored to the current operating system,
/// including an `OPENLATCH_API_KEY` env var fallback in all cases.
pub fn keychain_suggestion() -> String {
    if cfg!(target_os = "linux") {
        "Install and start gnome-keyring or KWallet, or set OPENLATCH_API_KEY env var as fallback."
            .into()
    } else if cfg!(target_os = "windows") {
        "Check Windows Credential Manager in Control Panel, or set OPENLATCH_API_KEY env var."
            .into()
    } else if cfg!(target_os = "macos") {
        "Check Keychain Access.app permissions, or set OPENLATCH_API_KEY env var.".into()
    } else {
        "Set OPENLATCH_API_KEY env var as an alternative to OS keychain.".into()
    }
}

// ---------------------------------------------------------------------------
// Telemetry errors (OL-1700–1799)
// ---------------------------------------------------------------------------

/// The telemetry.json consent file contains invalid JSON and cannot be parsed.
pub const ERR_TELEMETRY_CONFIG_CORRUPT: &str = "OL-1700";
/// Failed to write the telemetry.json consent file (permissions or I/O error).
pub const ERR_TELEMETRY_WRITE_FAILED: &str = "OL-1701";
/// A telemetry batch POST failed (informational — events dropped, no retry).
pub const ERR_TELEMETRY_POST_FAILED: &str = "OL-1702";
/// Telemetry subsystem failed to initialise (baked key missing, channel error).
pub const ERR_TELEMETRY_INIT_FAILED: &str = "OL-1703";

// ---------------------------------------------------------------------------
// Doctor (--fix / --restore / --rescue) errors (OL-1800–1899)
// ---------------------------------------------------------------------------

/// `doctor --fix` journal file is present but cannot be parsed (--restore can't drive).
pub const ERR_DOCTOR_JOURNAL_CORRUPT: &str = "OL-1800";
/// `doctor --restore` was invoked with no prior `--fix` journal on disk.
pub const ERR_DOCTOR_RESTORE_NO_JOURNAL: &str = "OL-1801";
/// `doctor --rescue` could not write the archive (disk full, permissions, etc.).
pub const ERR_DOCTOR_RESCUE_WRITE_FAILED: &str = "OL-1802";
/// `doctor --rescue` produced an archive but one or more collectors errored.
pub const ERR_DOCTOR_RESCUE_PARTIAL: &str = "OL-1803";

// ---------------------------------------------------------------------------
// Tamper-evidence errors (OL-1900–1999)
// ---------------------------------------------------------------------------

/// HMAC key unavailable — both OS keyring and file fallback failed.
pub const ERR_HMAC_KEY_UNAVAILABLE: &str = "OL-1900";
/// The hook-state.json file exists but cannot be parsed (invalid JSON or unknown schema_version).
pub const ERR_STATE_FILE_CORRUPT: &str = "OL-1901";
/// Atomic write to hook-state.json failed after settings.json was written.
pub const ERR_STATE_FILE_WRITE_FAILED: &str = "OL-1902";
/// The `_openlatch.v` field carries a version we don't understand.
pub const ERR_MARKER_SCHEMA_UNSUPPORTED: &str = "OL-1903";
/// JCS canonicalization rejected the hook entry (internal error; should not happen).
pub const ERR_CANONICALIZATION_FAILED: &str = "OL-1904";
/// A legacy `_openlatch: true` boolean marker was found and will be upgraded (info-level).
pub const ERR_LEGACY_MARKER_DETECTED: &str = "OL-1905";

// ---------------------------------------------------------------------------
// Bug report sentinel
// ---------------------------------------------------------------------------

/// Code assigned to all internal/unexpected errors routed through bug_report().
pub const ERR_BUG: &str = "OL-9999";

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

    #[test]
    fn test_ol_error_display_full_format() {
        // OlError Display output matches D-06/D-07 format. Uses a stable
        // error code unaffected by the CloudEvents migration (OL-1002 is
        // retained; OL-1001 was retired when the wire format opened up).
        let err = OlError::new(ERR_EVENT_TOO_LARGE, "Event body exceeds 1 MB limit")
            .with_suggestion("Split the payload into smaller events")
            .with_docs("https://docs.openlatch.ai/errors/OL-1002");

        let output = format!("{err}");
        assert!(
            output.starts_with("Error: Event body exceeds 1 MB limit (OL-1002)"),
            "Expected error header, got: {output}"
        );
        assert!(
            output.contains("Suggestion: Split the payload"),
            "Missing suggestion"
        );
        assert!(
            output.contains("Docs: https://docs.openlatch.ai"),
            "Missing docs URL"
        );
    }

    #[test]
    fn test_ol_error_display_no_suggestion() {
        // Test 2: OlError without suggestion omits the suggestion line
        let err = OlError::new(ERR_EVENT_TOO_LARGE, "Event body exceeds 1 MB limit")
            .with_docs("https://docs.openlatch.ai/errors/OL-1002");

        let output = format!("{err}");
        assert!(
            !output.contains("Suggestion:"),
            "Should not contain suggestion line: {output}"
        );
        assert!(
            output.contains("Docs:"),
            "Should still contain docs line: {output}"
        );
    }

    #[test]
    fn test_ol_error_display_no_docs_url() {
        // Test 3: OlError without docs_url omits the docs line
        let err = OlError::new(ERR_INVALID_REGEX, "Invalid regex pattern")
            .with_suggestion("Fix the regex in your config");

        let output = format!("{err}");
        assert!(
            !output.contains("Docs:"),
            "Should not contain docs line: {output}"
        );
        assert!(
            output.contains("Suggestion:"),
            "Should still contain suggestion: {output}"
        );
    }

    #[test]
    fn test_ol_error_display_no_optional_fields() {
        // Test 3 (extended): OlError with neither suggestion nor docs
        let err = OlError::new(ERR_PORT_IN_USE, "Port 7443 is already in use");

        let output = format!("{err}");
        assert_eq!(output, "Error: Port 7443 is already in use (OL-1500)");
    }

    #[test]
    fn test_error_code_constants_exist() {
        // Error code constants exist for each subsystem range. OL-1001
        // (ERR_UNKNOWN_AGENT) was retired with the CloudEvents migration.
        assert_eq!(ERR_EVENT_TOO_LARGE, "OL-1002");
        assert_eq!(ERR_INVALID_REGEX, "OL-1100");
        assert_eq!(ERR_INVALID_CONFIG, "OL-1300");
        assert_eq!(ERR_MISSING_CONFIG_FIELD, "OL-1301");
        assert_eq!(ERR_EVENT_DEDUPED, "OL-1003");
        assert_eq!(ERR_HOOK_CONFLICT, "OL-1403");
        assert_eq!(ERR_PORT_IN_USE, "OL-1500");
        assert_eq!(ERR_ALREADY_RUNNING, "OL-1501");
        assert_eq!(ERR_DAEMON_START_FAILED, "OL-1502");
        assert_eq!(ERR_VERSION_OUTDATED, "OL-1503");
        // Cloud forwarding errors
        assert_eq!(ERR_CLOUD_UNREACHABLE, "OL-1200");
        assert_eq!(ERR_CLOUD_AUTH_FAILED, "OL-1201");
        assert_eq!(ERR_CLOUD_RATE_LIMITED, "OL-1202");
        // Auth / credential errors
        assert_eq!(ERR_NO_CREDENTIALS, "OL-1600");
        assert_eq!(ERR_TOKEN_EXPIRED, "OL-1601");
        assert_eq!(ERR_KEYCHAIN_UNAVAILABLE, "OL-1602");
        assert_eq!(ERR_KEYCHAIN_PERMISSION, "OL-1603");
        assert_eq!(ERR_FILE_FALLBACK_ERROR, "OL-1604");
        // Tamper-evidence errors
        assert_eq!(ERR_HMAC_KEY_UNAVAILABLE, "OL-1900");
        assert_eq!(ERR_STATE_FILE_CORRUPT, "OL-1901");
        assert_eq!(ERR_STATE_FILE_WRITE_FAILED, "OL-1902");
        assert_eq!(ERR_MARKER_SCHEMA_UNSUPPORTED, "OL-1903");
        assert_eq!(ERR_CANONICALIZATION_FAILED, "OL-1904");
        assert_eq!(ERR_LEGACY_MARKER_DETECTED, "OL-1905");
    }

    #[test]
    fn test_keychain_suggestion_returns_non_empty_string() {
        // keychain_suggestion() must return a non-empty, platform-specific string
        let suggestion = keychain_suggestion();
        assert!(
            !suggestion.is_empty(),
            "keychain_suggestion must not be empty"
        );
        // On Windows it should mention Credential Manager or env var
        #[cfg(target_os = "windows")]
        assert!(
            suggestion.contains("Credential Manager") || suggestion.contains("OPENLATCH_API_KEY"),
            "Windows suggestion must mention Credential Manager or env var: {suggestion}"
        );
        // On macOS it should mention Keychain Access
        #[cfg(target_os = "macos")]
        assert!(
            suggestion.contains("Keychain") || suggestion.contains("OPENLATCH_API_KEY"),
            "macOS suggestion must mention Keychain: {suggestion}"
        );
        // On Linux it should mention gnome-keyring or Secret Service
        #[cfg(target_os = "linux")]
        assert!(
            suggestion.contains("gnome-keyring") || suggestion.contains("OPENLATCH_API_KEY"),
            "Linux suggestion must mention gnome-keyring or env var: {suggestion}"
        );
    }

    #[test]
    fn test_ol_error_implements_std_error() {
        // Test 5: OlError implements std::error::Error trait
        let err = OlError::new(ERR_EVENT_TOO_LARGE, "test");
        // Verify the trait bound by using it as &dyn std::error::Error
        let _boxed: Box<dyn std::error::Error> = Box::new(err);
    }

    #[test]
    fn test_bug_report_sets_code_ol_9999() {
        let err = OlError::bug_report("Unexpected panic in envelope module");
        assert_eq!(err.code, "OL-9999");
        assert!(err.suggestion.is_some());
        assert!(err.docs_url.is_some());
        let url = err.docs_url.unwrap();
        assert!(url.contains("github.com/OpenLatch/openlatch-client/issues/new"));
    }

    #[test]
    fn test_percent_encode_spaces_and_newlines() {
        assert_eq!(percent_encode("hello world"), "hello%20world");
        assert_eq!(percent_encode("line1\nline2"), "line1%0Aline2");
    }
}