"""Core rendering module for rp."""

from __future__ import annotations

from dataclasses import dataclass

from rich.console import Console, RenderableType
from rich.json import JSON as RichJSON
from rich.markdown import Markdown
from rich.padding import Padding
from rich.syntax import Syntax

from rp.debug import DebugLogger, log_debug
from rp.pager import MousePager


@dataclass
class RenderOptions:
    """Rendering options for file display.

    Attributes:
        theme: Pygments color theme name.
        line_numbers: Show line numbers. ``None`` enables them for code only.
        pager: Use pager for output. ``None`` auto-detects terminal output.
        debug: Optional debug logger for render and pager decisions.
    """

    theme: str = "monokai"
    line_numbers: bool | None = None
    pager: bool | None = None
    debug: DebugLogger | None = None


_MARKDOWN_TYPES: set[str] = {"markdown", "md"}
_JSON_TYPES: set[str] = {"json"}


def render(
    content: str, file_type: str, console: Console, options: RenderOptions
) -> None:
    """Render content to the console with syntax highlighting.

    Renders Markdown with Rich Markdown, JSON with Rich JSON with a Syntax
    fallback, and all other types with Pygments Syntax highlighting.

    Args:
        content: File content to render.
        file_type: Pygments lexer name.
        console: Rich console to render to.
        options: Rendering options (theme, line numbers, pager).
    """
    line_numbers = options.line_numbers
    if line_numbers is None:
        line_numbers = file_type not in _MARKDOWN_TYPES and file_type not in _JSON_TYPES
        log_debug(
            options.debug,
            f"render: auto-set line_numbers={line_numbers} for {file_type!r}",
        )

    use_pager = options.pager
    if use_pager is None:
        import sys

        stdout_is_tty = sys.stdout.isatty()
        use_pager = stdout_is_tty
        log_debug(
            options.debug,
            f"pager: auto-detected {'enabled' if use_pager else 'disabled'} "
            f"because stdout is {'a' if stdout_is_tty else 'not a'} TTY",
        )
    else:
        log_debug(
            options.debug,
            f"pager: explicitly {'enabled' if use_pager else 'disabled'}",
        )

    renderable: RenderableType
    if file_type in _MARKDOWN_TYPES:
        renderable = Markdown(content)
    elif file_type in _JSON_TYPES:
        try:
            renderable = RichJSON(content)
        except (SyntaxError, ValueError):
            log_debug(options.debug, "render: invalid JSON, falling back to syntax")
            renderable = Syntax(
                content, "json", theme=options.theme, line_numbers=line_numbers
            )
    else:
        try:
            renderable = Syntax(
                content, file_type, theme=options.theme, line_numbers=line_numbers
            )
        except Exception:
            log_debug(
                options.debug,
                f"render: unknown lexer {file_type!r}, falling back to plain text",
            )
            renderable = Syntax(
                content, "text", theme=options.theme, line_numbers=line_numbers
            )

    padded = Padding(renderable, (1, 2))

    if use_pager:
        log_debug(options.debug, "pager: opening pager")
        with console.pager(pager=MousePager(debug=options.debug), styles=True):
            console.print(padded)
    else:
        log_debug(options.debug, "pager: writing directly to the console")
        console.print(padded)