use crate::matcher::{Match, MatchReceiver};
use crate::keyboard::KeyboardSender;
use crate::config::ConfigManager;
use crate::config::BackendType;
use crate::clipboard::ClipboardManager;
use log::{info};
use crate::ui::UIManager;

pub struct Engine<'a, S: KeyboardSender, C: ClipboardManager, M: ConfigManager,
                  U: UIManager> {
    sender: S,
    clipboard_manager: &'a C,
    config_manager: &'a M,
    ui_manager: &'a U,
}

impl <'a, S: KeyboardSender, C: ClipboardManager, M: ConfigManager, U: UIManager>
    Engine<'a, S, C, M, U> {
    pub fn new<'b>(sender: S, clipboard_manager: &'b C, config_manager: &'b M, ui_manager: &'b U) -> Engine<'b, S, C, M, U> {
        Engine{sender, clipboard_manager, config_manager, ui_manager }
    }
}

impl <'a, S: KeyboardSender, C: ClipboardManager, M: ConfigManager, U: UIManager>
    MatchReceiver for Engine<'a, S, C, M, U>{

    fn on_match(&self, m: &Match) {
        let config = self.config_manager.active_config();

        if config.disabled {
            return;
        }

        self.sender.delete_string(m.trigger.len() as i32);

        match config.backend {
            BackendType::Inject => {
                // Send the expected string. On linux, newlines are managed automatically
                // while on windows and macos, we need to emulate a Enter key press.

                if cfg!(target_os = "linux") {
                    self.sender.send_string(m.replace.as_str());
                }else{
                    // To handle newlines, substitute each "\n" char with an Enter key press.
                    let splits = m.replace.lines();

                    for (i, split) in splits.enumerate() {
                        if i > 0 {
                            self.sender.send_enter();
                        }

                        self.sender.send_string(split);
                    }
                }
            },
            BackendType::Clipboard => {
                self.clipboard_manager.set_clipboard(m.replace.as_str());
                self.sender.trigger_paste();
            },
        }
    }

    fn on_toggle(&self, status: bool) {
        let message = if status {
            "espanso enabled"
        }else{
            "espanso disabled"
        };

        info!("Toggled: {}", message);

        self.ui_manager.notify(message);
    }
}