use std::cmp::{max, min};
use std::env;
use std::path::PathBuf;

use directories_next::ProjectDirs;
use home::home_dir;
use image_hasher::{FilterType, HashAlg};
use log::{debug, error, info, warn};
use serde::{Deserialize, Serialize};
use slint::{ComponentHandle, Model, ModelRc};

use czkawka_core::common::{get_all_available_threads, set_number_of_threads};
use czkawka_core::common_items::{DEFAULT_EXCLUDED_DIRECTORIES, DEFAULT_EXCLUDED_ITEMS};

use crate::common::{create_excluded_directories_model_from_pathbuf, create_included_directories_model_from_pathbuf, create_vec_model_from_vec_string};
use crate::{Callabler, GuiState, MainWindow, Settings};

pub const DEFAULT_MINIMUM_SIZE_KB: i32 = 16;
pub const DEFAULT_MAXIMUM_SIZE_KB: i32 = i32::MAX / 1024;
pub const DEFAULT_MINIMUM_CACHE_SIZE: i32 = 256;
pub const DEFAULT_MINIMUM_PREHASH_CACHE_SIZE: i32 = 256;

// (Hash size, Maximum difference) - Ehh... to simplify it, just use everywhere 40 as maximum similarity - for now I'm to lazy to change it, when hash size changes
// So if you want to change it, you need to change it in multiple places
pub const ALLOWED_HASH_SIZE_VALUES: &[(u8, u8)] = &[(8, 40), (16, 40), (32, 40), (64, 40)];

pub const ALLOWED_RESIZE_ALGORITHM_VALUES: &[(&str, &str, FilterType)] = &[
    ("lanczos3", "Lanczos3", FilterType::Lanczos3),
    ("gaussian", "Gaussian", FilterType::Gaussian),
    ("catmullrom", "CatmullRom", FilterType::CatmullRom),
    ("triangle", "Triangle", FilterType::Triangle),
    ("nearest", "Nearest", FilterType::Nearest),
];

pub const ALLOWED_HASH_TYPE_VALUES: &[(&str, &str, HashAlg)] = &[
    ("mean", "Mean", HashAlg::Mean),
    ("gradient", "Gradient", HashAlg::Gradient),
    ("blockhash", "BlockHash", HashAlg::Blockhash),
    ("vertgradient", "VertGradient", HashAlg::VertGradient),
    ("doublegradient", "DoubleGradient", HashAlg::DoubleGradient),
];

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct SettingsCustom {
    #[serde(default = "default_included_directories")]
    pub included_directories: Vec<PathBuf>,
    #[serde(default)]
    pub included_directories_referenced: Vec<PathBuf>,
    #[serde(default = "default_excluded_directories")]
    pub excluded_directories: Vec<PathBuf>,
    #[serde(default = "default_excluded_items")]
    pub excluded_items: String,
    #[serde(default)]
    pub allowed_extensions: String,
    #[serde(default)]
    pub excluded_extensions: String,
    #[serde(default = "minimum_file_size")]
    pub minimum_file_size: i32,
    #[serde(default = "maximum_file_size")]
    pub maximum_file_size: i32,
    #[serde(default = "ttrue")]
    pub recursive_search: bool,
    #[serde(default = "ttrue")]
    pub use_cache: bool,
    #[serde(default)]
    pub save_also_as_json: bool,
    #[serde(default)]
    pub move_deleted_files_to_trash: bool,
    #[serde(default)]
    pub ignore_other_file_systems: bool,
    #[serde(default)]
    pub thread_number: i32,
    #[serde(default = "ttrue")]
    pub duplicate_image_preview: bool,
    #[serde(default = "ttrue")]
    pub duplicate_hide_hard_links: bool,
    #[serde(default = "ttrue")]
    pub duplicate_use_prehash: bool,
    #[serde(default = "minimal_hash_cache_size")]
    pub duplicate_minimal_hash_cache_size: i32,
    #[serde(default = "minimal_prehash_cache_size")]
    pub duplicate_minimal_prehash_cache_size: i32,
    #[serde(default = "ttrue")]
    pub duplicate_delete_outdated_entries: bool,
    #[serde(default = "ttrue")]
    pub similar_images_show_image_preview: bool,
    #[serde(default = "ttrue")]
    pub similar_images_delete_outdated_entries: bool,
    #[serde(default = "ttrue")]
    pub similar_videos_delete_outdated_entries: bool,
    #[serde(default = "ttrue")]
    pub similar_music_delete_outdated_entries: bool,
    #[serde(default = "default_sub_hash_size")]
    pub similar_images_sub_hash_size: u8,
    #[serde(default = "default_hash_type")]
    pub similar_images_sub_hash_type: String,
    #[serde(default = "default_resize_algorithm")]
    pub similar_images_sub_resize_algorithm: String,
    #[serde(default)]
    pub similar_images_sub_ignore_same_size: bool,
    #[serde(default = "default_similarity")]
    pub similar_images_sub_similarity: i32,
}

pub fn default_similarity() -> i32 {
    10
}

impl Default for SettingsCustom {
    fn default() -> Self {
        serde_json::from_str("{}").unwrap()
    }
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct BasicSettings {
    #[serde(default = "default_language")]
    pub language: String,
    #[serde(default)]
    pub default_preset: i32,
    #[serde(default = "default_preset_names")]
    pub preset_names: Vec<String>,
}

impl Default for BasicSettings {
    fn default() -> Self {
        serde_json::from_str("{}").unwrap()
    }
}

pub fn connect_changing_settings_preset(app: &MainWindow) {
    let a = app.as_weak();
    app.global::<Callabler>().on_changed_settings_preset(move || {
        let app = a.upgrade().unwrap();
        let current_item = app.global::<Settings>().get_settings_preset_idx();
        let loaded_data = load_data_from_file::<SettingsCustom>(get_config_file(current_item + 1));
        match loaded_data {
            Ok(loaded_data) => {
                set_settings_to_gui(&app, &loaded_data);
                app.set_text_summary_text(format!("Changed and loaded properly preset {}", current_item + 1).into());
            }
            Err(e) => {
                set_settings_to_gui(&app, &SettingsCustom::default());
                app.set_text_summary_text(format!("Cannot change and load preset {} - reason {e}", current_item + 1).into());
                error!("Failed to change preset - {e}, using default instead");
            }
        }
    });
    let a = app.as_weak();
    app.global::<Callabler>().on_save_current_preset(move || {
        let app = a.upgrade().unwrap();
        let settings = app.global::<Settings>();
        let current_item = settings.get_settings_preset_idx();
        let result = save_data_to_file(get_config_file(current_item), &collect_settings(&app));
        match result {
            Ok(()) => {
                app.set_text_summary_text(format!("Saved preset {}", current_item + 1).into());
            }
            Err(e) => {
                app.set_text_summary_text(format!("Cannot save preset {} - reason {e}", current_item + 1).into());
                error!("{e}");
            }
        }
    });
    let a = app.as_weak();
    app.global::<Callabler>().on_reset_current_preset(move || {
        let app = a.upgrade().unwrap();
        let settings = app.global::<Settings>();
        let current_item = settings.get_settings_preset_idx();
        set_settings_to_gui(&app, &SettingsCustom::default());
        app.set_text_summary_text(format!("Reset preset {}", current_item + 1).into());
    });
    let a = app.as_weak();
    app.global::<Callabler>().on_load_current_preset(move || {
        let app = a.upgrade().unwrap();
        let settings = app.global::<Settings>();
        let current_item = settings.get_settings_preset_idx();
        let loaded_data = load_data_from_file::<SettingsCustom>(get_config_file(current_item));
        match loaded_data {
            Ok(loaded_data) => {
                set_settings_to_gui(&app, &loaded_data);
                app.set_text_summary_text(format!("Loaded preset {}", current_item + 1).into());
            }
            Err(e) => {
                set_settings_to_gui(&app, &SettingsCustom::default());
                let err_message = format!("Cannot load preset {} - reason {e}", current_item + 1);
                app.set_text_summary_text(err_message.into());
                error!("{e}");
            }
        }
    });
}

pub fn create_default_settings_files() {
    let base_config_file = get_base_config_file();
    if let Some(base_config_file) = base_config_file {
        if !base_config_file.is_file() {
            let _ = save_data_to_file(Some(base_config_file), &BasicSettings::default());
        }
    }

    for i in 1..=10 {
        let config_file = get_config_file(i);
        if let Some(config_file) = config_file {
            if !config_file.is_file() {
                let _ = save_data_to_file(Some(config_file), &SettingsCustom::default());
            }
        }
    }
}

pub fn load_settings_from_file(app: &MainWindow) {
    let result_base_settings = load_data_from_file::<BasicSettings>(get_base_config_file());

    let mut base_settings;
    if let Ok(base_settings_temp) = result_base_settings {
        base_settings = base_settings_temp;
    } else {
        info!("Cannot load base settings, using default instead");
        base_settings = BasicSettings::default();
    }

    let results_custom_settings = load_data_from_file::<SettingsCustom>(get_config_file(base_settings.default_preset));

    let mut custom_settings;
    if let Ok(custom_settings_temp) = results_custom_settings {
        custom_settings = custom_settings_temp;
    } else {
        info!("Cannot load custom settings, using default instead");
        custom_settings = SettingsCustom::default();
    }

    // Validate here values and set "proper"
    // preset_names should have 10 items
    if base_settings.preset_names.len() > 10 {
        base_settings.preset_names.truncate(10);
    } else if base_settings.preset_names.len() < 10 {
        while base_settings.preset_names.len() < 10 {
            base_settings.preset_names.push(format!("Preset {}", base_settings.preset_names.len() + 1));
        }
    }
    base_settings.default_preset = max(min(base_settings.default_preset, 9), 0);
    custom_settings.thread_number = max(min(custom_settings.thread_number, get_all_available_threads() as i32), 0);

    // Ended validating
    set_settings_to_gui(app, &custom_settings);
    set_base_settings_to_gui(app, &base_settings);
    set_number_of_threads(custom_settings.thread_number as usize);
}

pub fn save_all_settings_to_file(app: &MainWindow) {
    save_base_settings_to_file(app);
    save_custom_settings_to_file(app);
}

pub fn save_base_settings_to_file(app: &MainWindow) {
    let result = save_data_to_file(get_base_config_file(), &collect_base_settings(app));

    if let Err(e) = result {
        error!("{e}");
    }
}

pub fn save_custom_settings_to_file(app: &MainWindow) {
    let current_item = app.global::<Settings>().get_settings_preset_idx();
    let result = save_data_to_file(get_config_file(current_item), &collect_settings(app));

    if let Err(e) = result {
        error!("{e}");
    }
}

pub fn load_data_from_file<T>(config_file: Option<PathBuf>) -> Result<T, String>
where
    for<'de> T: Deserialize<'de>,
{
    let current_time = std::time::Instant::now();
    let Some(config_file) = config_file else {
        return Err("Cannot get config file".into());
    };
    if !config_file.is_file() {
        return Err("Config file doesn't exists".into());
    }

    let result = match std::fs::read_to_string(&config_file) {
        Ok(serialized) => {
            debug!("Loading data from file {:?} took {:?}", config_file, current_time.elapsed());

            match serde_json::from_str(&serialized) {
                Ok(custom_settings) => Ok(custom_settings),
                Err(e) => Err(format!("Cannot deserialize settings: {e}")),
            }
        }
        Err(e) => Err(format!("Cannot read config file: {e}")),
    };

    debug!("Loading and converting data from file {:?} took {:?}", config_file, current_time.elapsed());

    result
}

pub fn save_data_to_file<T>(config_file: Option<PathBuf>, serializable_data: &T) -> Result<(), String>
where
    T: Serialize,
{
    let current_time = std::time::Instant::now();
    let Some(config_file) = config_file else {
        return Err("Cannot get config file".into());
    };
    // Create dirs if not exists
    if let Some(parent) = config_file.parent() {
        if let Err(e) = std::fs::create_dir_all(parent) {
            return Err(format!("Cannot create config folder: {e}"));
        }
    }

    match serde_json::to_string_pretty(&serializable_data) {
        Ok(serialized) => {
            if let Err(e) = std::fs::write(&config_file, serialized) {
                return Err(format!("Cannot save config file: {e}"));
            }
        }
        Err(e) => {
            return Err(format!("Cannot serialize settings: {e}"));
        }
    }

    debug!("Saving data to file {:?} took {:?}", config_file, current_time.elapsed());
    Ok(())
}

pub fn get_base_config_file() -> Option<PathBuf> {
    let configs = ProjectDirs::from("pl", "Qarmin", "Krokiet")?;
    let config_folder = configs.config_dir();
    let base_config_file = config_folder.join("config_general.json");
    Some(base_config_file)
}
pub fn get_config_file(number: i32) -> Option<PathBuf> {
    let configs = ProjectDirs::from("pl", "Qarmin", "Krokiet")?;
    let config_folder = configs.config_dir();
    let config_file = config_folder.join(format!("config_preset_{number}.json"));
    Some(config_file)
}

pub fn set_base_settings_to_gui(app: &MainWindow, basic_settings: &BasicSettings) {
    let settings = app.global::<Settings>();
    // settings.set_language(basic_settings.language.clone());
    settings.set_settings_preset_idx(basic_settings.default_preset);
    settings.set_settings_presets(ModelRc::new(create_vec_model_from_vec_string(basic_settings.preset_names.clone())));
}
pub fn set_settings_to_gui(app: &MainWindow, custom_settings: &SettingsCustom) {
    let settings = app.global::<Settings>();

    // Included directories
    let included_directories = create_included_directories_model_from_pathbuf(&custom_settings.included_directories, &custom_settings.included_directories_referenced);
    settings.set_included_directories_model(included_directories);

    // Excluded directories
    let excluded_directories = create_excluded_directories_model_from_pathbuf(&custom_settings.excluded_directories);
    settings.set_excluded_directories_model(excluded_directories);

    settings.set_excluded_items(custom_settings.excluded_items.clone().into());
    settings.set_allowed_extensions(custom_settings.allowed_extensions.clone().into());
    settings.set_excluded_extensions(custom_settings.excluded_extensions.clone().into());
    settings.set_minimum_file_size(custom_settings.minimum_file_size.to_string().into());
    settings.set_maximum_file_size(custom_settings.maximum_file_size.to_string().into());
    settings.set_use_cache(custom_settings.use_cache);
    settings.set_save_as_json(custom_settings.save_also_as_json);
    settings.set_move_to_trash(custom_settings.move_deleted_files_to_trash);
    settings.set_ignore_other_filesystems(custom_settings.ignore_other_file_systems);
    settings.set_thread_number(custom_settings.thread_number as f32);

    settings.set_recursive_search(custom_settings.recursive_search);
    settings.set_duplicate_image_preview(custom_settings.duplicate_image_preview);
    settings.set_duplicate_hide_hard_links(custom_settings.duplicate_hide_hard_links);
    settings.set_duplicate_use_prehash(custom_settings.duplicate_use_prehash);
    settings.set_duplicate_minimal_hash_cache_size(custom_settings.duplicate_minimal_hash_cache_size.to_string().into());
    settings.set_duplicate_minimal_prehash_cache_size(custom_settings.duplicate_minimal_prehash_cache_size.to_string().into());
    settings.set_duplicate_delete_outdated_entries(custom_settings.duplicate_delete_outdated_entries);
    settings.set_similar_images_show_image_preview(custom_settings.similar_images_show_image_preview);
    settings.set_similar_images_delete_outdated_entries(custom_settings.similar_images_delete_outdated_entries);
    settings.set_similar_videos_delete_outdated_entries(custom_settings.similar_videos_delete_outdated_entries);
    settings.set_similar_music_delete_outdated_entries(custom_settings.similar_music_delete_outdated_entries);

    let similar_images_sub_hash_size_idx = if let Some(idx) = ALLOWED_HASH_SIZE_VALUES
        .iter()
        .position(|(hash_size, _max_similarity)| *hash_size == custom_settings.similar_images_sub_hash_size)
    {
        idx
    } else {
        warn!(
            "Value of hash size \"{}\" is invalid, setting it to default value",
            custom_settings.similar_images_sub_hash_size
        );
        0
    };
    settings.set_similar_images_sub_hash_size_index(similar_images_sub_hash_size_idx as i32);

    let similar_images_sub_hash_type_idx = if let Some(idx) = ALLOWED_HASH_TYPE_VALUES
        .iter()
        .position(|(settings_key, _gui_name, _hash_type)| *settings_key == custom_settings.similar_images_sub_hash_type)
    {
        idx
    } else {
        warn!(
            "Value of hash type \"{}\" is invalid, setting it to default value",
            custom_settings.similar_images_sub_hash_type
        );
        0
    };
    settings.set_similar_images_sub_hash_type_index(similar_images_sub_hash_type_idx as i32);

    let similar_images_sub_resize_algorithm_idx = if let Some(idx) = ALLOWED_RESIZE_ALGORITHM_VALUES
        .iter()
        .position(|(settings_key, _gui_name, _resize_alg)| *settings_key == custom_settings.similar_images_sub_resize_algorithm)
    {
        idx
    } else {
        warn!(
            "Value of resize algorithm \"{}\" is invalid, setting it to default value",
            custom_settings.similar_images_sub_resize_algorithm
        );
        0
    };
    settings.set_similar_images_sub_resize_algorithm_index(similar_images_sub_resize_algorithm_idx as i32);

    settings.set_similar_images_sub_ignore_same_size(custom_settings.similar_images_sub_ignore_same_size);
    settings.set_similar_images_sub_max_similarity(40.0); // TODO this is now set to stable 40
    settings.set_similar_images_sub_current_similarity(custom_settings.similar_images_sub_similarity as f32);

    // Clear text
    app.global::<GuiState>().set_info_text("".into());
}

pub fn collect_settings(app: &MainWindow) -> SettingsCustom {
    let settings = app.global::<Settings>();

    let included_directories_model = settings.get_included_directories_model();
    let included_directories = included_directories_model.iter().map(|model| PathBuf::from(model.path.as_str())).collect::<Vec<_>>();
    let included_directories_referenced = included_directories_model
        .iter()
        .filter(|model| model.referenced_folder)
        .map(|model| PathBuf::from(model.path.as_str()))
        .collect::<Vec<_>>();

    let excluded_directories_model = settings.get_excluded_directories_model();
    let excluded_directories = excluded_directories_model.iter().map(|model| PathBuf::from(model.path.as_str())).collect::<Vec<_>>();

    let excluded_items = settings.get_excluded_items().to_string();
    let allowed_extensions = settings.get_allowed_extensions().to_string();
    let excluded_extensions = settings.get_excluded_extensions().to_string();
    let minimum_file_size = settings.get_minimum_file_size().parse::<i32>().unwrap_or(DEFAULT_MINIMUM_SIZE_KB);
    let maximum_file_size = settings.get_maximum_file_size().parse::<i32>().unwrap_or(DEFAULT_MAXIMUM_SIZE_KB);

    let recursive_search = settings.get_recursive_search();
    let use_cache = settings.get_use_cache();
    let save_also_as_json = settings.get_save_as_json();
    let move_deleted_files_to_trash = settings.get_move_to_trash();
    let ignore_other_file_systems = settings.get_ignore_other_filesystems();
    let thread_number = settings.get_thread_number().round() as i32;

    let duplicate_image_preview = settings.get_duplicate_image_preview();
    let duplicate_hide_hard_links = settings.get_duplicate_hide_hard_links();
    let duplicate_use_prehash = settings.get_duplicate_use_prehash();
    let duplicate_minimal_hash_cache_size = settings.get_duplicate_minimal_hash_cache_size().parse::<i32>().unwrap_or(DEFAULT_MINIMUM_CACHE_SIZE);
    let duplicate_minimal_prehash_cache_size = settings
        .get_duplicate_minimal_prehash_cache_size()
        .parse::<i32>()
        .unwrap_or(DEFAULT_MINIMUM_PREHASH_CACHE_SIZE);
    let duplicate_delete_outdated_entries = settings.get_duplicate_delete_outdated_entries();

    let similar_images_show_image_preview = settings.get_similar_images_show_image_preview();
    let similar_images_delete_outdated_entries = settings.get_similar_images_delete_outdated_entries();

    let similar_videos_delete_outdated_entries = settings.get_similar_videos_delete_outdated_entries();

    let similar_music_delete_outdated_entries = settings.get_similar_music_delete_outdated_entries();

    let similar_images_sub_hash_size_idx = settings.get_similar_images_sub_hash_size_index();
    let similar_images_sub_hash_size = ALLOWED_HASH_SIZE_VALUES[similar_images_sub_hash_size_idx as usize].0;

    let similar_images_sub_hash_type_idx = settings.get_similar_images_sub_hash_type_index();
    let similar_images_sub_hash_type = ALLOWED_HASH_TYPE_VALUES[similar_images_sub_hash_type_idx as usize].0.to_string();

    let similar_images_sub_resize_algorithm_idx = settings.get_similar_images_sub_resize_algorithm_index();
    let similar_images_sub_resize_algorithm = ALLOWED_RESIZE_ALGORITHM_VALUES[similar_images_sub_resize_algorithm_idx as usize].0.to_string();

    let similar_images_sub_ignore_same_size = settings.get_similar_images_sub_ignore_same_size();
    let similar_images_sub_similarity = settings.get_similar_images_sub_current_similarity().round() as i32;
    SettingsCustom {
        included_directories,
        included_directories_referenced,
        excluded_directories,
        excluded_items,
        allowed_extensions,
        excluded_extensions,
        minimum_file_size,
        maximum_file_size,
        recursive_search,
        use_cache,
        save_also_as_json,
        move_deleted_files_to_trash,
        ignore_other_file_systems,
        thread_number,
        duplicate_image_preview,
        duplicate_hide_hard_links,
        duplicate_use_prehash,
        duplicate_minimal_hash_cache_size,
        duplicate_minimal_prehash_cache_size,
        duplicate_delete_outdated_entries,
        similar_images_show_image_preview,
        similar_images_delete_outdated_entries,
        similar_videos_delete_outdated_entries,
        similar_music_delete_outdated_entries,
        similar_images_sub_hash_size,
        similar_images_sub_hash_type,
        similar_images_sub_resize_algorithm,
        similar_images_sub_ignore_same_size,
        similar_images_sub_similarity,
    }
}

pub fn collect_base_settings(app: &MainWindow) -> BasicSettings {
    let settings = app.global::<Settings>();

    let default_preset = settings.get_settings_preset_idx();
    let preset_names = settings.get_settings_presets().iter().map(|x| x.to_string()).collect::<Vec<_>>();

    assert_eq!(preset_names.len(), 10);
    BasicSettings {
        language: "en".to_string(),
        default_preset,
        preset_names,
    }
}

fn default_included_directories() -> Vec<PathBuf> {
    let mut included_directories = vec![];
    if let Ok(current_dir) = env::current_dir() {
        included_directories.push(current_dir.to_string_lossy().to_string());
    } else if let Some(home_dir) = home_dir() {
        included_directories.push(home_dir.to_string_lossy().to_string());
    } else if cfg!(target_family = "unix") {
        included_directories.push("/".to_string());
    } else {
        // This could be set to default
        included_directories.push("C:\\".to_string());
    };
    included_directories.sort();
    included_directories.iter().map(PathBuf::from).collect::<Vec<_>>()
}

fn default_excluded_directories() -> Vec<PathBuf> {
    let mut excluded_directories = DEFAULT_EXCLUDED_DIRECTORIES.iter().map(PathBuf::from).collect::<Vec<_>>();
    excluded_directories.sort();
    excluded_directories
}

fn default_excluded_items() -> String {
    DEFAULT_EXCLUDED_ITEMS.to_string()
}

fn default_language() -> String {
    "en".to_string()
}

fn default_preset_names() -> Vec<String> {
    (0..10).map(|x| format!("Preset {}", x + 1)).collect::<Vec<_>>()
}

fn minimum_file_size() -> i32 {
    DEFAULT_MINIMUM_SIZE_KB
}
fn maximum_file_size() -> i32 {
    DEFAULT_MAXIMUM_SIZE_KB
}
fn ttrue() -> bool {
    true
}
fn minimal_hash_cache_size() -> i32 {
    DEFAULT_MINIMUM_CACHE_SIZE
}
fn minimal_prehash_cache_size() -> i32 {
    DEFAULT_MINIMUM_PREHASH_CACHE_SIZE
}

pub fn default_resize_algorithm() -> String {
    ALLOWED_RESIZE_ALGORITHM_VALUES[0].0.to_string()
}
pub fn default_hash_type() -> String {
    ALLOWED_HASH_TYPE_VALUES[0].0.to_string()
}
pub fn default_sub_hash_size() -> u8 {
    16
}