//! Lineage tracking commands

use clap::Subcommand;

use crate::{config::Config, error::Result, output};

#[derive(Subcommand)]
pub enum LineageCommand {
    /// Trace dependencies for a schema
    Trace {
        /// Schema ID
        id: String,

        /// Maximum depth to trace
        #[arg(short, long)]
        depth: Option<usize>,

        /// Show upstream dependencies
        #[arg(short, long)]
        upstream: bool,

        /// Show downstream dependents
        #[arg(short = 'D', long)]
        downstream: bool,
    },

    /// Show impact analysis for a schema change
    Impact {
        /// Schema ID
        id: String,

        /// Change type (field-added, field-removed, type-changed)
        #[arg(short, long)]
        change_type: String,

        /// Field name
        #[arg(short, long)]
        field: Option<String>,
    },

    /// Detect circular dependencies
    DetectCircular,

    /// Export lineage graph
    Export {
        /// Schema ID (or all if not specified)
        id: Option<String>,

        /// Export format (graphml, dot, json)
        #[arg(short, long, default_value = "dot")]
        format: String,

        /// Output file
        #[arg(short, long)]
        output: Option<String>,
    },

    /// Find shortest path between two schemas
    Path {
        /// From schema ID
        from: String,

        /// To schema ID
        to: String,
    },

    /// Get graph statistics
    Stats,
}

pub async fn execute(cmd: LineageCommand, config: &Config, format: output::OutputFormat) -> Result<()> {
    match cmd {
        LineageCommand::Trace { id, depth, upstream, downstream } => {
            trace_dependencies(config, &id, depth, upstream, downstream, format).await
        }
        LineageCommand::Impact { id, change_type, field } => {
            impact_analysis(config, &id, &change_type, field.as_deref(), format).await
        }
        LineageCommand::DetectCircular => {
            detect_circular(config, format).await
        }
        LineageCommand::Export { id, format: export_format, output: output_file } => {
            export_lineage(config, id.as_deref(), &export_format, output_file.as_deref(), format).await
        }
        LineageCommand::Path { from, to } => {
            find_path(config, &from, &to, format).await
        }
        LineageCommand::Stats => {
            show_stats(config, format).await
        }
    }
}

async fn trace_dependencies(
    _config: &Config,
    id: &str,
    depth: Option<usize>,
    upstream: bool,
    downstream: bool,
    _format: output::OutputFormat,
) -> Result<()> {
    let direction = if upstream && !downstream {
        "upstream"
    } else if downstream && !upstream {
        "downstream"
    } else {
        "both"
    };

    output::print_info(&format!(
        "Tracing {} dependencies for schema: {} (depth: {:?})",
        direction, id, depth
    ));

    // Mock output
    output::print_table(
        vec!["Schema ID", "Subject", "Relation", "Depth"],
        vec![
            vec!["abc-123".to_string(), "com.example.Address".to_string(), "depends_on".to_string(), "1".to_string()],
            vec!["def-456".to_string(), "com.example.Profile".to_string(), "used_by".to_string(), "1".to_string()],
        ],
    );

    Ok(())
}

async fn impact_analysis(
    _config: &Config,
    id: &str,
    change_type: &str,
    field: Option<&str>,
    _format: output::OutputFormat,
) -> Result<()> {
    output::print_info(&format!(
        "Analyzing impact of change: {} on schema {} (field: {:?})",
        change_type, id, field
    ));

    // Mock analysis result
    output::print_warning("BREAKING CHANGE DETECTED");
    println!("\nAffected schemas: 5");
    println!("Affected applications: 3");
    println!("Estimated migration effort: 4.5 hours");
    println!("\nRecommendations:");
    println!("  1. Create migration scripts for all affected consumers");
    println!("  2. Coordinate deployment with downstream teams");
    println!("  3. Consider adding backward compatibility layer");

    Ok(())
}

async fn detect_circular(_config: &Config, _format: output::OutputFormat) -> Result<()> {
    output::print_info("Detecting circular dependencies...");

    // Mock result
    output::print_success("No circular dependencies detected");

    Ok(())
}

async fn export_lineage(
    _config: &Config,
    id: Option<&str>,
    export_format: &str,
    output_file: Option<&str>,
    _format: output::OutputFormat,
) -> Result<()> {
    let scope = id.map(|s| format!("schema {}", s)).unwrap_or_else(|| "all schemas".to_string());
    output::print_info(&format!("Exporting lineage for {} in {} format", scope, export_format));

    let output_path = output_file.unwrap_or("lineage.graph");

    // Mock export
    output::print_success(&format!("Lineage exported to: {}", output_path));

    Ok(())
}

async fn find_path(_config: &Config, from: &str, to: &str, _format: output::OutputFormat) -> Result<()> {
    output::print_info(&format!("Finding path from {} to {}", from, to));

    // Mock path
    println!("\nPath found (3 hops):");
    println!("  {} -> com.example.Address -> com.example.User -> {}", from, to);

    Ok(())
}

async fn show_stats(_config: &Config, _format: output::OutputFormat) -> Result<()> {
    output::print_info("Graph statistics:");

    output::print_table(
        vec!["Metric", "Value"],
        vec![
            vec!["Total nodes".to_string(), "247".to_string()],
            vec!["Total edges".to_string(), "612".to_string()],
            vec!["Root nodes".to_string(), "15".to_string()],
            vec!["Leaf nodes".to_string(), "42".to_string()],
            vec!["Avg dependencies per schema".to_string(), "2.47".to_string()],
            vec!["Max depth".to_string(), "8".to_string()],
        ],
    );

    Ok(())
}
