"""Template system for card generation."""

import json
import os
from pathlib import Path
from typing import Any, Optional
from dataclasses import dataclass, field


@dataclass
class Template:
    """Card template configuration."""
    name: str
    layout: dict[str, Any] = field(default_factory=dict)
    colors: dict[str, str] = field(default_factory=dict)
    fonts: dict[str, str] = field(default_factory=dict)
    spacing: dict[str, int] = field(default_factory=dict)


class TemplateLoader:
    """Loader and validator for card templates."""

    DEFAULT_TEMPLATES = {
        "default": {
            "layout": {
                "header_height": 60,
                "section_spacing": 20,
                "option_spacing": 10,
                "margin": 30,
                "columns": 2
            },
            "colors": {
                "header_bg": "#2E3440",
                "header_text": "#FFFFFF",
                "section_title": "#88C0D0",
                "option_flag": "#A3BE8C",
                "option_desc": "#ECEFF4",
                "background": "#FFFFFF",
                "border": "#4C566A"
            },
            "fonts": {
                "header": ("Helvetica", 24, "B"),
                "section": ("Helvetica", 14, "B"),
                "option_flag": ("Courier", 10, "B"),
                "option_desc": ("Helvetica", 9, ""),
                "synopsis": ("Courier", 11, ""),
                "body": ("Helvetica", 10, "")
            },
            "spacing": {
                "line_height": 14,
                "margin": 20,
                "section_padding": 15
            }
        },
        "minimal": {
            "layout": {
                "header_height": 40,
                "section_spacing": 15,
                "option_spacing": 8,
                "margin": 20,
                "columns": 2
            },
            "colors": {
                "header_bg": "#FFFFFF",
                "header_text": "#000000",
                "section_title": "#666666",
                "option_flag": "#000000",
                "option_desc": "#333333",
                "background": "#FFFFFF",
                "border": "#CCCCCC"
            },
            "fonts": {
                "header": ("Helvetica", 18, ""),
                "section": ("Helvetica", 11, "B"),
                "option_flag": ("Courier", 9, ""),
                "option_desc": ("Helvetica", 8, ""),
                "synopsis": ("Courier", 9, ""),
                "body": ("Helvetica", 8, "")
            },
            "spacing": {
                "line_height": 12,
                "margin": 15,
                "section_padding": 10
            }
        },
        "compact": {
            "layout": {
                "header_height": 35,
                "section_spacing": 10,
                "option_spacing": 5,
                "margin": 15,
                "columns": 3
            },
            "colors": {
                "header_bg": "#1A1A2E",
                "header_text": "#FFFFFF",
                "section_title": "#00D9FF",
                "option_flag": "#00FF88",
                "option_desc": "#AAAAAA",
                "background": "#16213E",
                "border": "#0F3460"
            },
            "fonts": {
                "header": ("Helvetica", 14, "B"),
                "section": ("Helvetica", 10, "B"),
                "option_flag": ("Courier", 7, "B"),
                "option_desc": ("Helvetica", 7, ""),
                "synopsis": ("Courier", 8, ""),
                "body": ("Helvetica", 7, "")
            },
            "spacing": {
                "line_height": 10,
                "margin": 10,
                "section_padding": 8
            }
        },
        "dark": {
            "layout": {
                "header_height": 50,
                "section_spacing": 18,
                "option_spacing": 12,
                "margin": 25,
                "columns": 2
            },
            "colors": {
                "header_bg": "#1E1E1E",
                "header_text": "#61AFEF",
                "section_title": "#C678DD",
                "option_flag": "#98C379",
                "option_desc": "#ABB2BF",
                "background": "#282C34",
                "border": "#3E4451"
            },
            "fonts": {
                "header": ("Helvetica", 20, "B"),
                "section": ("Helvetica", 12, "B"),
                "option_flag": ("Courier", 9, "B"),
                "option_desc": ("Helvetica", 8, ""),
                "synopsis": ("Courier", 10, ""),
                "body": ("Helvetica", 9, "")
            },
            "spacing": {
                "line_height": 13,
                "margin": 18,
                "section_padding": 12
            }
        }
    }

    def __init__(self, template_dir: Optional[str] = None):
        self.template_dir = Path(template_dir) if template_dir else Path(__file__).parent.parent / "templates"

    def list_templates(self) -> list[str]:
        """List available template names."""
        templates = list(self.DEFAULT_TEMPLATES.keys())
        if self.template_dir.exists():
            for f in self.template_dir.glob("*.json"):
                if f.stem not in templates:
                    templates.append(f.stem)
        return sorted(templates)

    def load(self, name: str) -> Template:
        """Load a template by name."""
        if name in self.DEFAULT_TEMPLATES:
            data = self.DEFAULT_TEMPLATES[name]
            return Template(name=name, **data)

        template_path = self.template_dir / f"{name}.json"
        if template_path.exists():
            with open(template_path, 'r') as f:
                data = json.load(f)
            if "fonts" in data:
                for key in data["fonts"]:
                    if isinstance(data["fonts"][key], list):
                        data["fonts"][key] = tuple(data["fonts"][key])
            return Template(name=name, **data)

        raise ValueError(f"Template '{name}' not found. Available: {', '.join(self.list_templates())}")

    def load_custom(self, path: str) -> Template:
        """Load a custom template from file path."""
        with open(path, 'r') as f:
            data = json.load(f)
        return Template(name=Path(path).stem, **data)

    def get_template_path(self, name: str) -> Optional[Path]:
        """Get the file path for a template if it exists."""
        if name in self.DEFAULT_TEMPLATES:
            return None
        template_path = self.template_dir / f"{name}.json"
        if template_path.exists():
            return template_path
        return None