// file: crates/ksp-app-config-desk/src/documents.rs
// version: 1

//! Generic Config document inventory, diagnostics and validated repair services.

use ts_rs::TS; // rust-rules: derive-import

const STATUS_VALID: &str = "valid";
const STATUS_INVALID: &str = "invalid";
const STAGE_VALID: &str = "valid";
const STAGE_READ: &str = "read";
const STAGE_JSON: &str = "json";
const STAGE_SCHEMA: &str = "schema";
const STAGE_SEMANTIC: &str = "semantic";
const STAGE_EFFECTIVE: &str = "effective";
const STAGE_OTHER: &str = "other";

/// Safe inventory row for one Config document registered by `ksp-config-lib`.
#[derive(Clone, Debug, serde::Serialize, TS)]
#[serde(rename_all = "camelCase")]
#[ts(export, export_to = "../frontend/ts/bindings/ksp_app_config_desk/documents/ConfigDocumentSummaryDto.ts")]
pub(crate) struct ConfigDocumentSummaryDto {
    /// Stable logical Config identifier.
    pub(crate) file_id: String,
    /// Current Config-managed relative filename mapping.
    pub(crate) filename: String,
    /// Registered validation schema identifier.
    pub(crate) schema_file_id: std::option::Option<String>,
    /// Resolved filesystem path controlled by Config.
    pub(crate) path: String,
    /// `valid` or `invalid` according to the backend Config authority.
    pub(crate) validation_status: String,
    /// Backend diagnostic stage: valid/read/json/schema/semantic/effective/other.
    pub(crate) diagnostic_stage: String,
    /// Safe bounded diagnostic when the document is invalid.
    pub(crate) diagnostic: std::option::Option<crate::CommandErrorDto>,
}

/// Detailed management view for one registered Config document.
#[derive(Clone, Debug, serde::Serialize, TS)]
#[serde(rename_all = "camelCase")]
#[ts(export, export_to = "../frontend/ts/bindings/ksp_app_config_desk/documents/ConfigDocumentDetailDto.ts")]
pub(crate) struct ConfigDocumentDetailDto {
    /// Current validation/inventory summary.
    pub(crate) summary: ConfigDocumentSummaryDto,
    /// Raw Config-managed source when the file can be read, even if its JSON/schema/semantics are invalid.
    pub(crate) source: std::option::Option<String>,
}

/// Result of one validated raw-source repair attempt that reached persistence successfully.
#[derive(Clone, Debug, serde::Serialize, TS)]
#[serde(rename_all = "camelCase")]
#[ts(export, export_to = "../frontend/ts/bindings/ksp_app_config_desk/documents/ConfigDocumentSaveResultDto.ts")]
pub(crate) struct ConfigDocumentSaveResultDto {
    /// Whether persisted source bytes changed.
    pub(crate) source_changed: bool,
    /// Whether Config consumers need a reload to observe the changed document.
    pub(crate) reload_required: bool,
    /// Fresh detail reloaded after persistence.
    pub(crate) document: ConfigDocumentDetailDto,
}

/// Safe document-specific command error with backend-owned diagnostic classification.
#[derive(Clone, Debug, serde::Serialize, TS)]
#[serde(rename_all = "camelCase")]
#[ts(export, export_to = "../frontend/ts/bindings/ksp_app_config_desk/documents/ConfigDocumentErrorDto.ts")]
pub(crate) struct ConfigDocumentErrorDto {
    /// Backend diagnostic stage associated with the failure.
    pub(crate) diagnostic_stage: String,
    /// Bounded KSP error projection without arbitrary context/source values.
    pub(crate) error: crate::CommandErrorDto,
}

impl ConfigDocumentErrorDto {
    fn from_error(error: &ksp_core_lib::Error) -> Self {
        return Self { diagnostic_stage: classify_error(error).to_owned(), error: crate::CommandErrorDto::from_error(error) };
    }
}

/// Lists all Config-kind documents from the Config registry and evaluates their current backend validation state.
pub(crate) fn inventory(state: &crate::AppState) -> std::vec::Vec<ConfigDocumentSummaryDto> {
    let management = state.config_management();
    let engine = management.engine();
    let mut documents = std::vec::Vec::new();
    for descriptor in engine.registry().descriptors() {
        if descriptor.kind() != ksp_config_lib::ConfigFileKind::Config {
            continue;
        }
        documents.push(build_summary(management, descriptor));
    }
    ksp_logging_lib::debug!(
        target: crate::TRACING_TARGET,
        domain = crate::TRACING_DOMAIN_DOCUMENTS,
        document_count = documents.len(),
        "Config document inventory evaluated"
    );
    return documents;
}

/// Loads one Config document detail, including raw source when Config can read it.
pub(crate) fn detail(state: &crate::AppState, file_id_text: &str) -> std::result::Result<ConfigDocumentDetailDto, ConfigDocumentErrorDto> {
    let file_id = parse_config_file_id(file_id_text);
    let file_id = match file_id {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(ConfigDocumentErrorDto::from_error(&error)),
    };
    let management = state.config_management();
    let descriptor = management.engine().registry().descriptor(&file_id);
    let descriptor = match descriptor {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(ConfigDocumentErrorDto::from_error(&error)),
    };
    if descriptor.kind() != ksp_config_lib::ConfigFileKind::Config {
        let error = ksp_core_lib::Error::new(crate::ERROR_CODE_DOCUMENT_KIND_INVALID, "requested document is not a Config-kind document");
        return std::result::Result::Err(ConfigDocumentErrorDto::from_error(&error));
    }
    let summary = build_summary(management, descriptor);
    let source = management.read_source(&file_id);
    let source = match source {
        std::result::Result::Ok(value) => std::option::Option::Some(value.content().to_owned()),
        std::result::Result::Err(_) => std::option::Option::None,
    };
    ksp_logging_lib::debug!(
        target: crate::TRACING_TARGET,
        domain = crate::TRACING_DOMAIN_DOCUMENTS,
        file_id = file_id.as_str(),
        validation_status = summary.validation_status.as_str(),
        diagnostic_stage = summary.diagnostic_stage.as_str(),
        source_available = source.is_some(),
        "Config document detail loaded"
    );
    return std::result::Result::Ok(ConfigDocumentDetailDto { summary, source });
}

/// Validates and atomically persists one raw Config source candidate, then reloads the document detail.
pub(crate) fn save_source(
    state: &crate::AppState,
    file_id_text: &str,
    source: &str,
) -> std::result::Result<ConfigDocumentSaveResultDto, ConfigDocumentErrorDto> {
    let file_id = parse_config_file_id(file_id_text);
    let file_id = match file_id {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(ConfigDocumentErrorDto::from_error(&error)),
    };
    let report = state.config_management().save_source_candidate(&file_id, source);
    let report = match report {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(ConfigDocumentErrorDto::from_error(&error)),
    };
    let document = detail(state, file_id.as_str());
    let document = match document {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(error),
    };
    ksp_logging_lib::info!(
        target: crate::TRACING_TARGET,
        domain = crate::TRACING_DOMAIN_DOCUMENTS,
        file_id = file_id.as_str(),
        source_changed = report.source_changed(),
        reload_required = report.reload_required(),
        "validated Config document source candidate persisted"
    );
    return std::result::Result::Ok(ConfigDocumentSaveResultDto {
        source_changed: report.source_changed(),
        reload_required: report.reload_required(),
        document,
    });
}

fn parse_config_file_id(value: &str) -> ksp_core_lib::Result<ksp_config_lib::ConfigFileId> {
    let file_id = ksp_config_lib::ConfigFileId::new(value.to_owned());
    let file_id = match file_id {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(error),
    };
    return std::result::Result::Ok(file_id);
}

fn build_summary(management: &ksp_config_lib::ConfigManagement, descriptor: &ksp_config_lib::ConfigFileDescriptor) -> ConfigDocumentSummaryDto {
    let engine = management.engine();
    let path = engine.registry().resolve_path(engine.bootstrap(), descriptor.file_id());
    let path = match path {
        std::result::Result::Ok(value) => value.to_string_lossy().into_owned(),
        std::result::Result::Err(_) => descriptor.filename().to_string_lossy().into_owned(),
    };
    let validation = validate_effective_document(management, descriptor.file_id());
    let (validation_status, diagnostic_stage, diagnostic) = match validation {
        std::result::Result::Ok(()) => (STATUS_VALID.to_owned(), STAGE_VALID.to_owned(), std::option::Option::None),
        std::result::Result::Err(error) => {
            (STATUS_INVALID.to_owned(), classify_error(&error).to_owned(), std::option::Option::Some(crate::CommandErrorDto::from_error(&error)))
        },
    };
    return ConfigDocumentSummaryDto {
        file_id: descriptor.file_id().as_str().to_owned(),
        filename: descriptor.filename().to_string_lossy().into_owned(),
        schema_file_id: descriptor.schema_file_id().map(|value| {
            return value.as_str().to_owned();
        }),
        path,
        validation_status,
        diagnostic_stage,
        diagnostic,
    };
}

fn validate_effective_document(management: &ksp_config_lib::ConfigManagement, file_id: &ksp_config_lib::ConfigFileId) -> ksp_core_lib::Result<()> {
    let validated = management.engine().load_validated_document(file_id);
    match validated {
        std::result::Result::Ok(_) => {},
        std::result::Result::Err(error) => return std::result::Result::Err(error),
    }
    if file_id.as_str() != ksp_config_lib::FILE_ID_STD_LOGGING {
        return std::result::Result::Ok(());
    }
    let environment = ksp_config_lib::ConfigEnvironment::load();
    let environment = match environment {
        std::result::Result::Ok(value) => value,
        std::result::Result::Err(error) => return std::result::Result::Err(error),
    };
    let resolved = management.engine().load_resolved_logging_config(std::option::Option::None, &environment);
    return match resolved {
        std::result::Result::Ok(_) => std::result::Result::Ok(()),
        std::result::Result::Err(error) => std::result::Result::Err(error),
    };
}

fn classify_error(error: &ksp_core_lib::Error) -> &'static str {
    let code = error.code();
    if code == ksp_config_lib::ERROR_CODE_JSON_FILE_READ_FAILED {
        if error_context_file_id_is_schema(error) {
            return STAGE_SCHEMA;
        }
        return STAGE_READ;
    }
    if code == ksp_config_lib::ERROR_CODE_JSON_SYNTAX_INVALID {
        if error_context_file_id_is_schema(error) {
            return STAGE_SCHEMA;
        }
        return STAGE_JSON;
    }
    if code == ksp_config_lib::ERROR_CODE_SCHEMA_INVALID || code == ksp_config_lib::ERROR_CODE_SCHEMA_VALIDATION_FAILED {
        return STAGE_SCHEMA;
    }
    if code == ksp_config_lib::ERROR_CODE_DOCUMENT_SEMANTIC_INVALID
        || code == ksp_config_lib::ERROR_CODE_PROFILE_NOT_FOUND
        || code == ksp_config_lib::ERROR_CODE_COMPOSITE_REFERENCE_INVALID
    {
        return STAGE_SEMANTIC;
    }
    if code == ksp_config_lib::ERROR_CODE_EFFECTIVE_CONFIG_INVALID
        || code == ksp_config_lib::ERROR_CODE_ENVIRONMENT_PLACEHOLDER_INVALID
        || code == ksp_config_lib::ERROR_CODE_ENVIRONMENT_VALUE_INVALID
        || code == ksp_config_lib::ERROR_CODE_ENVIRONMENT_VARIABLE_INVALID
        || code == ksp_config_lib::ERROR_CODE_ENVIRONMENT_VARIABLE_MISSING
        || code == ksp_config_lib::ERROR_CODE_DOTENV_FILE_READ_FAILED
        || code == ksp_config_lib::ERROR_CODE_DOTENV_SYNTAX_INVALID
    {
        return STAGE_EFFECTIVE;
    }
    return STAGE_OTHER;
}

fn error_context_file_id_is_schema(error: &ksp_core_lib::Error) -> bool {
    for field in error.context() {
        if field.key() == "file_id" {
            return field.value().starts_with("schema.");
        }
    }
    return false;
}

#[cfg(test)]
#[path = "../unit_tests/documents.rs"]
mod tests;