// SPDX-License-Identifier: GPL-3.0-or-later
// examples/cli.rs
//
// CLI test harness for the noctua_core document foundation.

use clap::{ArgGroup, Parser};
use noctua_core::document::manager::{DocumentCommand, DocumentManager, DocumentState};
use noctua_core::document::session::SessionKind;
use std::path::PathBuf;

fn print_session(manager: &DocumentManager, session_name: &str) {
    if let Some(session) = manager.session(session_name) {
        println!("Session '{}' ({:?})", session.name, session.kind);
        println!(
            "  Items: {}, current_index: {:?}",
            session.items.len(),
            session.current_index
        );
        for (i, item) in session.items.iter().enumerate() {
            let marker = if session.current_index == Some(i) {
                "*"
            } else {
                " "
            };
            println!(
                "  [{}] {} (page {})",
                marker,
                item.path.display(),
                item.page_index
            );
        }
    } else {
        println!("Session '{}' not found", session_name);
    }
}

fn handle_command(manager: &mut DocumentManager, command: DocumentCommand) {
    manager.handle(command);
    match &manager.state {
        DocumentState::Error(err) => {
            eprintln!("Error: {}", err);
            manager.state = DocumentState::Empty;
        }
        _ => {}
    }
}

#[derive(Parser, Debug)]
#[command(
    name = "noctua",
    about = "A document viewer for the COSMIC desktop",
    group(
        ArgGroup::new("source")
            .required(true)
            .args(["open_document", "open_directory", "open_session"])
    )
)]
struct Cli {
    /// Open a document (Raster, Vector, Portable)
    #[arg(long, value_name = "PATH")]
    open_document: Option<PathBuf>,

    /// Open a directory
    #[arg(long, value_name = "PATH")]
    open_directory: Option<PathBuf>,

    /// Open a session file (.ron)
    #[arg(long, value_name = "PATH")]
    open_session: Option<PathBuf>,
}

fn main() {
    env_logger::init();

    let cli = Cli::parse();
    let mut manager = DocumentManager::new();

    if let Some(path) = cli.open_session {
        manager.handle(DocumentCommand::OpenSession(path));
    } else if let Some(path) = cli.open_document {
        let dir = path
            .parent()
            .map(|p| p.to_path_buf())
            .unwrap_or_else(|| PathBuf::from("."));

        let session_name = dir
            .file_name()
            .and_then(|n| n.to_str())
            .unwrap_or("Browse")
            .to_string();

        if manager.session(&session_name).is_none() {
            manager.handle(DocumentCommand::CreateSession {
                name: session_name.clone(),
                kind: SessionKind::DirectoryBrowser,
                path: Some(dir.clone()),
            });
            manager.handle(DocumentCommand::ScanDirectory {
                session: session_name.clone(),
                dir,
            });
        }

        manager.handle(DocumentCommand::AddFileToSession {
            session: session_name,
            path,
        });
    } else if let Some(path) = cli.open_directory {
        let session_name = path
            .file_name()
            .and_then(|n| n.to_str())
            .unwrap_or("Browse")
            .to_string();

        if manager.session(&session_name).is_none() {
            manager.handle(DocumentCommand::CreateSession {
                name: session_name.clone(),
                kind: SessionKind::DirectoryBrowser,
                path: Some(path.clone()),
            });
            manager.handle(DocumentCommand::ScanDirectory {
                session: session_name.clone(),
                dir: path,
            });
        }

        manager.handle(DocumentCommand::SetActive(session_name));
    }

    match &manager.state {
        DocumentState::Empty => println!("UI: No document loaded."),
        DocumentState::Loading => println!("UI: Loading..."),
        DocumentState::Error(err) => eprintln!("UI: Error -> {err}"),
        DocumentState::Loaded(_) => {
            println!("UI: Document loaded.");

            if let Some(name) = manager.active_session_name.clone() {
                if let Some(session) = manager.session(&name) {
                    println!(
                        "UI: Session '{}' ({:?}) has {} items, current index: {:?}",
                        session.name,
                        session.kind,
                        session.items.len(),
                        session.current_index
                    );

                    match session.kind {
                        SessionKind::DirectoryBrowser => {
                            println!("UI: Display as directory browser (thumbnails in left panel)");
                        }
                        SessionKind::DocumentCollection => {
                            println!("UI: Display as document collection (pages)");
                        }
                    }
                }

                println!("\nUI: Test navigation...");
                handle_command(&mut manager, DocumentCommand::NavigateNext);
                if let Some(session) = manager.session(&name) {
                    println!(
                        "UI: After NavigateNext     -> index {:?}",
                        session.current_index
                    );
                }

                handle_command(&mut manager, DocumentCommand::NavigatePrevious);
                if let Some(session) = manager.session(&name) {
                    println!(
                        "UI: After NavigatePrevious -> index {:?}",
                        session.current_index
                    );
                }

                handle_command(&mut manager, DocumentCommand::SelectItem(0));
                if let Some(session) = manager.session(&name) {
                    println!(
                        "UI: After SelectItem(0)    -> index {:?}",
                        session.current_index
                    );
                }

                println!("\nUI: Test copy/move/delete...");
                handle_command(
                    &mut manager,
                    DocumentCommand::CreateSession {
                        name: "Favorites".to_string(),
                        kind: SessionKind::DocumentCollection,
                        path: None,
                    },
                );
                handle_command(
                    &mut manager,
                    DocumentCommand::CreateSession {
                        name: "Workspace".to_string(),
                        kind: SessionKind::DocumentCollection,
                        path: None,
                    },
                );

                println!("\nBefore CopyItemToSession:");
                print_session(&manager, "Favorites");

                handle_command(
                    &mut manager,
                    DocumentCommand::CopyItemToSession {
                        source_session: name.clone(),
                        target_session: "Favorites".to_string(),
                        source_item_index: 0,
                        target_item_index: None,
                    },
                );
                println!("\nAfter CopyItemToSession to Favorites:");
                print_session(&manager, "Favorites");

                println!("\n--- Test DeleteItemFromSession on DirectoryBrowser (should fail) ---");
                handle_command(
                    &mut manager,
                    DocumentCommand::DeleteItemFromSession {
                        session: name.clone(),
                        item_index: None,
                    },
                );

                println!("\n--- Test Move from Favorites to Workspace ---");
                println!("\nBefore Move:");
                print_session(&manager, "Favorites");
                print_session(&manager, "Workspace");

                handle_command(
                    &mut manager,
                    DocumentCommand::CopyItemToSession {
                        source_session: "Favorites".to_string(),
                        target_session: "Workspace".to_string(),
                        source_item_index: 0,
                        target_item_index: None,
                    },
                );

                handle_command(
                    &mut manager,
                    DocumentCommand::DeleteItemFromSession {
                        session: "Favorites".to_string(),
                        item_index: Some(0),
                    },
                );

                println!("\nAfter Move:");
                print_session(&manager, "Favorites");
                print_session(&manager, "Workspace");
            }
        }
    }
}