"""Alias suggestion command."""

import os
from pathlib import Path
from typing import Optional

import click
from rich.console import Console

from shellhist.core import HistoryLoader
from shellhist.core.export import generate_alias, generate_alias_name
from shellhist.core.patterns import detect_common_sequences


@click.command("suggest-aliases")
@click.option(
    "--history",
    "-H",
    type=str,
    help="Path to history file",
)
@click.option(
    "--auto-create",
    "-a",
    is_flag=True,
    default=False,
    help="Automatically create aliases without prompting",
)
@click.option(
    "--dry-run",
    "-n",
    is_flag=True,
    default=False,
    help="Preview aliases without creating them",
)
@click.option(
    "--shell-file",
    "-f",
    type=str,
    help="Shell config file to append to (default: ~/.bashrc or ~/.zshrc)",
)
@click.option(
    "--shell",
    "-s",
    type=click.Choice(["bash", "zsh"]),
    help="Shell type for parsing",
)
@click.option(
    "--min-occurrences",
    "-m",
    type=int,
    default=3,
    help="Minimum occurrences for pattern (default: 3)",
)
@click.pass_context
def suggest_aliases_command(
    ctx: click.Context,
    history: Optional[str],
    auto_create: bool,
    dry_run: bool,
    shell_file: Optional[str],
    shell: Optional[str],
    min_occurrences: int,
) -> None:
    """Suggest shell aliases for detected command patterns.
    
    Examples:
    
        \b
        shellhist suggest-aliases
        shellhist suggest-aliases --auto-create
        shellhist suggest-aliases --dry-run --shell-file ~/.bashrc
    """
    console = Console()
    
    try:
        loader = HistoryLoader(history_path=history)
        store = loader.load()
        
        if not store.entries:
            console.print("[yellow]No entries found in history.[/yellow]")
            return
        
        sequences = detect_common_sequences(
            store,
            max_length=4,
            min_occurrences=min_occurrences,
        )
        
        if not sequences:
            console.print(
                f"[yellow]No significant patterns found with minimum {min_occurrences} occurrences.[/yellow]"
            )
            console.print("Try lowering --min-occurrences or run more commands.")
            return
        
        shell_type = shell or ("zsh" if "zsh" in os.environ.get("SHELL", "") else "bash")
        
        if shell_file is None:
            home = os.path.expanduser("~")
            shell_file = f"{home}/.bashrc" if shell_type == "bash" else f"{home}/.zshrc"
        
        console.print(f"[bold cyan]Detected Patterns for Alias Suggestions[/bold cyan]\n")
        
        aliases_to_create = []
        
        for i, pattern in enumerate(sequences[:10], 1):
            alias_name = generate_alias_name(pattern)
            alias_line = generate_alias(pattern, alias_name)
            
            console.print(f"{i}. [cyan]{alias_name}[/cyan]")
            console.print(f"   Command: {' -> '.join(pattern.commands)}")
            console.print(f"   Alias: {alias_line}")
            console.print(f"   Frequency: {pattern.frequency} times\n")
            
            if dry_run:
                continue
            
            if auto_create:
                aliases_to_create.append(alias_line)
            else:
                if click.confirm(f"Create alias '{alias_name}'?", default=True):
                    aliases_to_create.append(alias_line)
        
        if not aliases_to_create:
            console.print("\n[yellow]No aliases selected for creation.[/yellow]")
            return
        
        if dry_run:
            console.print("\n[bold]Aliases to create (dry-run):[/bold]")
            for alias in aliases_to_create:
                console.print(f"  {alias}")
            return
        
        shell_path = Path(shell_file)
        shell_path.parent.mkdir(parents=True, exist_ok=True)
        
        with open(shell_file, "a", encoding="utf-8") as f:
            f.write("\n# Shell History Automation Tool - Generated Aliases\n")
            for alias in aliases_to_create:
                f.write(f"{alias}\n")
        
        console.print(
            f"\n[green]Successfully added {len(aliases_to_create)} aliases to {shell_file}[/green]"
        )
        console.print("Run 'source " + shell_file + "' or restart your shell to use them.")
        
    except FileNotFoundError as e:
        console.print(f"[red]Error: {e}[/red]")
        ctx.exit(1)
    except Exception as e:
        console.print(f"[red]Error suggesting aliases: {e}[/red]")
        ctx.exit(1)