#!/usr/bin/env bash
set -euo pipefail

CHOICE=""

while [[ $# -gt 0 ]]; do
    case "$1" in
        --fisher) CHOICE="fisher"; shift ;;
        --omf)    CHOICE="omf";    shift ;;
        *) echo "Usage: $0 [--fisher|--omf]"; exit 1 ;;
    esac
done

detect_pkg_manager() {
    if command -v apt &>/dev/null; then
        echo "apt"
    elif command -v dnf &>/dev/null; then
        echo "dnf"
    elif command -v pacman &>/dev/null; then
        echo "pacman"
    elif command -v zypper &>/dev/null; then
        echo "zypper"
    else
        echo "unknown"
    fi
}

install_fish() {
    local pm
    pm=$(detect_pkg_manager)
    case "$pm" in
        apt)
            sudo apt update && sudo apt install -y fish
            ;;
        dnf)
            sudo dnf install -y fish
            ;;
        pacman)
            sudo pacman -S --noconfirm fish
            ;;
        zypper)
            sudo zypper install -y fish
            ;;
        *)
            echo "No supported package manager found. Please install fish manually: https://fishshell.com"
            exit 1
            ;;
    esac
}

get_plugins_file() {
    local user_plugins="$HOME/.config/fish/fish_plugins"
    local repo_plugins="$(dirname "$0")/fish_plugins"
    if [ -f "$user_plugins" ]; then
        echo "$user_plugins"
    elif [ -f "$repo_plugins" ]; then
        echo "$repo_plugins"
    else
        echo ""
    fi
}

install_fisher_and_plugins() {
    local fisher_path="$HOME/.config/fisher"
    local fish_config_dir="$HOME/.config/fish"

    echo "Creating Fisher directory structure..."
    mkdir -p "$fisher_path"/{functions,completions,conf.d,themes}

    echo "Symlinking themes directory..."
    mkdir -p "$fish_config_dir"
    ln -sf "$fisher_path/themes" "$fish_config_dir/themes"

    echo "Installing Fisher plugin manager..."
    fish -c 'curl -sL https://raw.githubusercontent.com/jorgebucaran/fisher/main/functions/fisher.fish | source && fisher install jorgebucaran/fisher'

    local plugins_file
    plugins_file=$(get_plugins_file)
    if [ -n "$plugins_file" ]; then
        echo "Installing plugins from $(basename "$plugins_file")..."
        fish -c "fisher install < $plugins_file"
    else
        echo "No fish_plugins file found. Skipping plugin installation."
    fi
}

install_omf() {
    if [ ! -d "$HOME/.local/share/omf" ]; then
        echo "Installing Oh My Fish..."
        curl https://raw.githubusercontent.com/oh-my-fish/oh-my-fish/master/bin/install > install
        fish install --path=~/.local/share/omf --config=~/.config/omf
    else
        echo "Oh My Fish already installed."
    fi
}

install_bobthefish() {
    if command -v fish &>/dev/null && [ -f "$HOME/.local/share/omf/init.fish" ]; then
        echo "Installing bobthefish theme..."
        fish -c 'omf install bobthefish'
    fi
}

set_default_shell() {
    local fish_path
    fish_path=$(command -v fish)
    if [ "$SHELL" != "$fish_path" ]; then
        echo "Setting default shell to fish..."
        if grep -q "^$USER:" /etc/passwd 2>/dev/null; then
            chsh -s "$fish_path"
        else
            echo "Run this manually: chsh -s $fish_path"
        fi
    else
        echo "Fish is already your default shell."
    fi
}

main() {
    if [ -z "$CHOICE" ]; then
        while true; do
            read -p "Select fish plugin manager (fisher/omf): " CHOICE
            case "$CHOICE" in
                fisher|omf) break ;;
                *) echo "Please enter 'fisher' or 'omf'" ;;
            esac
        done
    fi

    install_fish

    case "$CHOICE" in
        fisher)
            install_fisher_and_plugins
            ;;
        omf)
            install_omf
            install_bobthefish
            ;;
    esac

    set_default_shell

    echo
    echo "=== Installation complete ==="
    echo "Log out and back in, or run: exec fish"
}

main