"""Explain command for Local Code Assistant."""

from pathlib import Path
from typing import Optional

import click
from rich.console import Console
from rich.markdown import Markdown
from rich.panel import Panel

from local_code_assistant.commands.base import BaseCommand
from local_code_assistant.prompts.templates import LanguageConfig, PromptTemplates
from local_code_assistant.services.ollama import OllamaService

console = Console()


class ExplainCommand(BaseCommand):
    """Command for explaining code."""

    def __init__(self, ollama: OllamaService, config):
        """Initialize explain command.

        Args:
            ollama: Ollama service instance.
            config: Configuration service instance.
        """
        super().__init__(ollama, config)
        self.supported_languages = LanguageConfig.get_supported_languages()

    def run(
        self,
        code: str,
        language: Optional[str] = None,
        format_markdown: bool = False
    ) -> str:
        """Execute code explanation.

        Args:
            code: Code to explain.
            language: Programming language (auto-detected if not provided).
            format_markdown: Whether to format as markdown.

        Returns:
            Explanation text.
        """
        if not self.ollama.check_connection():
            raise click.ClickException(
                "Cannot connect to Ollama. Make sure it's running."
            )

        if language is None:
            language = self._detect_language(code)

        if language not in self.supported_languages:
            language = "text"

        console.print("[dim]Analyzing code...[/dim]")

        full_prompt = PromptTemplates.code_explanation(
            language=language,
            code=code
        )

        system_prompt = PromptTemplates.build_system_prompt(
            "You are explaining code to a developer. Be clear and concise."
        )

        try:
            explanation = self.ollama.generate(
                prompt=full_prompt,
                model=self._get_model(),
                system=system_prompt,
                temperature=self._get_temperature(0.3)
            )

            self._display_output(explanation, format_markdown)

            return explanation

        except Exception as e:
            raise click.ClickException(f"Explanation failed: {str(e)}") from e

    def run_file(
        self,
        file: Path,
        format_markdown: bool = False
    ) -> str:
        """Explain code from a file.

        Args:
            file: Path to file.
            format_markdown: Whether to format as markdown.

        Returns:
            Explanation text.
        """
        if not file.exists():
            raise click.ClickException(f"File not found: {file}")

        code = file.read_text()
        language = self._detect_language_from_file(file)

        return self.run(code, language, format_markdown)

    def _detect_language(self, code: str) -> str:
        """Detect programming language from code content.

        Args:
            code: Source code.

        Returns:
            Detected language.
        """
        if "def " in code or "import " in code or "class " in code:
            return "python"
        elif "function " in code or "const " in code or "let " in code:
            return "javascript"
        elif "interface " in code or "type " in code or ": string" in code:
            return "typescript"
        elif "func " in code or "package " in code:
            return "go"
        elif "fn " in code or "let " in code or "struct " in code:
            return "rust"

        return "text"

    def _detect_language_from_file(self, file: Path) -> str:
        """Detect language from file extension.

        Args:
            file: File path.

        Returns:
            Language name.
        """
        suffix = file.suffix.lower()

        language_map = {
            ".py": "python",
            ".js": "javascript",
            ".ts": "typescript",
            ".tsx": "typescript",
            ".go": "go",
            ".rs": "rust"
        }

        return language_map.get(suffix, "text")

    def _display_output(self, explanation: str, as_markdown: bool):
        """Display explanation.

        Args:
            explanation: Explanation text.
            as_markdown: Whether to render as markdown.
        """
        if as_markdown:
            console.print(Panel(Markdown(explanation), title="Explanation"))
        else:
            console.print(Panel(explanation, title="Explanation"))


@click.command()
@click.argument("file", type=click.Path(exists=True, path_type=Path))
@click.option(
    "--language", "-l",
    type=click.Choice(LanguageConfig.get_supported_languages()),
    default=None,
    help="Programming language (auto-detected if not specified)"
)
@click.option(
    "--markdown/--no-markdown",
    default=False,
    help="Format output as markdown"
)
@click.pass_context
def explain_cmd(
    ctx: click.Context,
    file: Path,
    language: Optional[str],
    markdown: bool
):
    """Explain code from a file.

    Example:
        local-code-assistant explain script.py
        local-code-assistant explain app.ts --markdown

    \f
    Args:
        ctx: Click context.
        file: Path to file to explain.
        language: Programming language.
        markdown: Format as markdown.
    """
    config = ctx.obj["config"]
    ollama_service = OllamaService(config)
    ctx.obj["ollama_service"] = ollama_service

    command = ExplainCommand(ollama_service, config)
    command.run_file(file, markdown)