"""
Configuration management for Curator

Three levels of configuration:
1. Global config (.Curator.!gtag next to Curator.py) - app-wide settings
2. Folder config (.Curator.!ftag in project root) - folder-specific settings
3. File tags (.{filename}.!tag) - per-file metadata (handled in file.py)
"""
import json
from pathlib import Path

# Global config file (next to the main script)
GLOBAL_CONFIG_FILE = Path(__file__).parent.parent.parent / ".Curator.!gtag"

# Folder config filename
FOLDER_CONFIG_NAME = ".Curator.!ftag"


# =============================================================================
# GLOBAL CONFIG - Application settings
# =============================================================================

# Tag schema: the single source of truth for which tag categories exist, how
# they are derived from ČSFD, and how they map to the Filmotéka folder tree.
# Each entry:
#   category       — tag category name (e.g. "Žánr")
#   csfd_field     — CSFDMovie attribute feeding it (genres / year / countries /
#                    rating / directors / actors), or None for a user-only category
#   transform      — named value transform: None (str) or "decade_band" (rating)
#   filmoteka_root — folder under the output: "" = at the root (e.g. genres),
#                    "Dle X" = grouping folder, None = filterable but no folders
#   filename_template — optional per-category hardlink name used only inside this
#                    category's folders (e.g. "{year} - {title}{ext}"); fields:
#                    title / year / rating / ext / stem / filename. Absent/None =
#                    keep the pool filename. Pool files are never renamed by this.
DEFAULT_TAG_SCHEMA = [
    {"category": "Žánr", "csfd_field": "genres", "transform": None, "filmoteka_root": ""},
    {"category": "Rok", "csfd_field": "year", "transform": None, "filmoteka_root": "Dle roku"},
    {"category": "Země původu", "csfd_field": "countries", "transform": None,
     "filmoteka_root": "Dle země původu"},
    {"category": "Hodnocení", "csfd_field": "rating", "transform": "decade_band",
     "filmoteka_root": "Dle hodnocení"},
]

DEFAULT_GLOBAL_CONFIG = {
    "window_geometry": "1200x800",
    "window_maximized": False,
    "last_folder": None,
    "sidebar_width": 250,
    "recent_folders": [],
    "pool_dir": None,        # managed pool root (single source of truth)
    "filmoteka_dir": None,   # generated Filmotéka output (hardlink tree)
    "copyasis_folders": ["Seriály"],  # pool subfolders mirrored 1:1 (copy-as-is)
    "tag_schema": DEFAULT_TAG_SCHEMA,  # tag categories + ČSFD/Filmotéka rules
}


def load_global_config() -> dict:
    """Load global application config"""
    if GLOBAL_CONFIG_FILE.exists():
        try:
            with open(GLOBAL_CONFIG_FILE, "r", encoding="utf-8") as f:
                config = json.load(f)
                # Merge with defaults for any missing keys
                for key, value in DEFAULT_GLOBAL_CONFIG.items():
                    if key not in config:
                        config[key] = value
                return config
        except Exception:
            return DEFAULT_GLOBAL_CONFIG.copy()
    return DEFAULT_GLOBAL_CONFIG.copy()


def save_global_config(cfg: dict):
    """Save global application config"""
    with open(GLOBAL_CONFIG_FILE, "w", encoding="utf-8") as f:
        json.dump(cfg, f, indent=2, ensure_ascii=False)


# =============================================================================
# FOLDER CONFIG - Per-folder settings
# =============================================================================

DEFAULT_FOLDER_CONFIG = {
    "ignore_patterns": [],
    "custom_tags": {},  # Additional tags specific to this folder
    "recursive": True,  # Whether to scan subfolders
    "hardlink_output_dir": None,  # Output directory for hardlink structure
    "hardlink_categories": None,  # Categories to include in hardlink (None = all)
}


def get_folder_config_path(folder: Path) -> Path:
    """Get path to folder config file"""
    return folder / FOLDER_CONFIG_NAME


def load_folder_config(folder: Path) -> dict:
    """Load folder-specific config"""
    config_path = get_folder_config_path(folder)
    if config_path.exists():
        try:
            with open(config_path, "r", encoding="utf-8") as f:
                config = json.load(f)
                # Merge with defaults for any missing keys
                for key, value in DEFAULT_FOLDER_CONFIG.items():
                    if key not in config:
                        config[key] = value
                return config
        except Exception:
            return DEFAULT_FOLDER_CONFIG.copy()
    return DEFAULT_FOLDER_CONFIG.copy()


def save_folder_config(folder: Path, cfg: dict):
    """Save folder-specific config"""
    config_path = get_folder_config_path(folder)
    with open(config_path, "w", encoding="utf-8") as f:
        json.dump(cfg, f, indent=2, ensure_ascii=False)


def folder_has_config(folder: Path) -> bool:
    """Check if folder has a tagger config"""
    return get_folder_config_path(folder).exists()


# =============================================================================
# BACKWARDS COMPATIBILITY
# =============================================================================

def load_config():
    """Legacy function - returns global config"""
    return load_global_config()


def save_config(cfg: dict):
    """Legacy function - saves global config"""
    save_global_config(cfg)