#!/usr/bin/env bash
# lib/shell.sh — Detect and install shell frameworks / version managers that
# are referenced in the user's dotfiles but are not yet present on disk.
#
# Why this exists:
#   Mackup restores dotfiles (e.g. ~/.zshrc) but not the *tools* those files
#   source.  If ~/.zshrc contains `source ~/.oh-my-zsh/oh-my-zsh.sh` and
#   Oh My Zsh is not installed, every new shell session prints an error.
#
# Architecture:
#   - _SSR_SHELL_DEPS defines built-in known frameworks (name|check|install).
#   - SSR_SHELL_DEPS_EXTRA in ssr.conf allows the user to add custom entries
#     using the same pipe-delimited format.
#   - ssr::shell::detect_and_install iterates all entries, runs the check,
#     and invokes the installer when the check fails.

# ---------------------------------------------------------------------------
# Built-in dependency definitions.
# Format: "name|check_expression|install_command"
#   check_expression  — any bash expression; success (exit 0) = already OK.
#   install_command   — run as the current user (no sudo).
# ---------------------------------------------------------------------------
_SSR_SHELL_DEPS=(
    # Oh My Zsh — most common zsh framework
    "oh-my-zsh\
|[[ -d \"\$HOME/.oh-my-zsh\" ]]\
|RUNZSH=no CHSH=no sh -c \"\$(curl -fsSL https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)\""

    # Prezto — lightweight zsh framework
    "prezto\
|[[ -d \"\$HOME/.zprezto\" ]]\
|git clone --recursive https://github.com/sorin-ionescu/prezto.git \"\${ZDOTDIR:-\$HOME}/.zprezto\""

    # Zinit — zsh plugin manager
    "zinit\
|[[ -d \"\${ZINIT_HOME:-\$HOME/.local/share/zinit/zinit.git}\" ]]\
|bash -c \"\$(curl --fail --show-error --silent --location https://raw.githubusercontent.com/zdharma-continuum/zinit/HEAD/scripts/install.sh)\""

    # Antigen — zsh plugin manager
    "antigen\
|[[ -f \"\$HOME/.antigen.zsh\" ]] || [[ -f \"\$HOME/.config/antigen/antigen.zsh\" ]]\
|mkdir -p \"\$HOME/.config/antigen\" && curl -sSL git.io/antigen -o \"\$HOME/.config/antigen/antigen.zsh\""

    # nvm — Node Version Manager
    "nvm\
|[[ -d \"\${NVM_DIR:-\$HOME/.nvm}\" ]]\
|PROFILE=/dev/null bash -c \"\$(curl -fsSL https://raw.githubusercontent.com/nvm-sh/nvm/HEAD/install.sh)\""

    # pyenv — Python version manager
    "pyenv\
|command -v pyenv >/dev/null 2>&1 || [[ -d \"\$HOME/.pyenv\" ]]\
|brew install pyenv"

    # rbenv — Ruby version manager
    "rbenv\
|command -v rbenv >/dev/null 2>&1 || [[ -d \"\$HOME/.rbenv\" ]]\
|brew install rbenv"

    # rustup — Rust toolchain installer
    "rustup\
|command -v rustup >/dev/null 2>&1 || [[ -d \"\$HOME/.rustup\" ]]\
|curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --no-modify-path"

    # SDKMAN — JVM version manager (Java, Kotlin, Groovy, …)
    "sdkman\
|[[ -d \"\$HOME/.sdkman\" ]]\
|curl -s https://get.sdkman.io | bash"

    # Starship prompt
    "starship\
|command -v starship >/dev/null 2>&1\
|brew install starship"

    # Powerlevel10k — when installed standalone (not via OMZ/zinit)
    "powerlevel10k\
|[[ -d \"\${ZSH_CUSTOM:-\$HOME/.oh-my-zsh/custom}/themes/powerlevel10k\" ]] \
  || [[ -d \"\$HOME/.local/share/powerlevel10k\" ]]\
|git clone --depth=1 https://github.com/romkatv/powerlevel10k.git \"\${ZSH_CUSTOM:-\$HOME/.oh-my-zsh/custom}/themes/powerlevel10k\""

    # asdf — universal version manager
    "asdf\
|command -v asdf >/dev/null 2>&1 || [[ -d \"\$HOME/.asdf\" ]]\
|brew install asdf"

    # mise (formerly rtx) — fast version manager
    "mise\
|command -v mise >/dev/null 2>&1\
|brew install mise"
)

# ---------------------------------------------------------------------------
# Internal helpers
# ---------------------------------------------------------------------------

# Return a list of RC files that are likely to reference external frameworks.
_ssr_shell_rc_files() {
    local files=(
        "$HOME/.zshrc"
        "$HOME/.zprofile"
        "$HOME/.bashrc"
        "$HOME/.bash_profile"
        "$HOME/.profile"
    )
    local f out=()
    for f in "${files[@]}"; do
        [[ -f "$f" ]] && out+=("$f")
    done
    printf '%s\n' "${out[@]}"
}

# Given a dependency name, return true if that name is referenced in any RC file.
# This lets us skip installers for things the user's dotfiles don't actually use.
_ssr_shell_dep_referenced() {
    local name="$1"
    local pattern
    case "$name" in
        oh-my-zsh)     pattern="oh-my-zsh" ;;
        prezto)        pattern="zprezto" ;;
        zinit)         pattern="zinit" ;;
        antigen)       pattern="antigen" ;;
        nvm)           pattern="NVM_DIR\|nvm.sh" ;;
        pyenv)         pattern="pyenv" ;;
        rbenv)         pattern="rbenv" ;;
        rustup)        pattern="rustup\|cargo" ;;
        sdkman)        pattern="sdkman\|SDKMAN_DIR" ;;
        starship)      pattern="starship" ;;
        powerlevel10k) pattern="powerlevel10k\|p10k" ;;
        asdf)          pattern="asdf" ;;
        mise)          pattern="mise" ;;
        *)             return 0 ;;   # unknown — always consider referenced
    esac

    local rcfile
    while IFS= read -r rcfile; do
        grep -qE "$pattern" "$rcfile" 2>/dev/null && return 0
    done < <(_ssr_shell_rc_files)
    return 1
}

# ---------------------------------------------------------------------------
# Public API
# ---------------------------------------------------------------------------

# Detect missing shell frameworks and install them.
# Iterates _SSR_SHELL_DEPS + SSR_SHELL_DEPS_EXTRA (from ssr.conf).
#
# Each entry: "name|check_expression|install_command"
#
# Skips any entry whose name is NOT referenced in the user's RC files
# (avoids installing things that are irrelevant to this machine).
ssr::shell::detect_and_install() {
    local -a all_deps=("${_SSR_SHELL_DEPS[@]}")

    # Append user-defined extras (SSR_SHELL_DEPS_EXTRA set in ssr.conf).
    if [[ -n "${SSR_SHELL_DEPS_EXTRA:-}" ]]; then
        local entry
        for entry in "${SSR_SHELL_DEPS_EXTRA[@]}"; do
            all_deps+=("$entry")
        done
    fi

    local name check_expr install_cmd
    local installed=0 skipped=0

    for dep in "${all_deps[@]}"; do
        # Parse pipe-delimited fields.
        name="$(        printf '%s' "$dep" | cut -d'|' -f1)"
        check_expr="$(  printf '%s' "$dep" | cut -d'|' -f2)"
        install_cmd="$( printf '%s' "$dep" | cut -d'|' -f3)"

        # Skip if not referenced in any RC file (reduces noise on clean systems).
        if ! _ssr_shell_dep_referenced "$name"; then
            skipped=$((skipped + 1))
            continue
        fi

        # Run the check expression; skip if already satisfied.
        if eval "$check_expr" 2>/dev/null; then
            ssr::log "shell dep OK: $name"
            continue
        fi

        ssr::warn "Shell dep missing: $name — installing…"
        if eval "$install_cmd" 2>&1 | { while IFS= read -r line; do ssr::log "  [$name] $line"; done; }; then
            ssr::ok "Installed: $name"
            installed=$((installed + 1))
        else
            ssr::warn "Install failed: $name (non-fatal — continue manually)"
        fi
    done

    if [[ $installed -gt 0 ]]; then
        ssr::ok "Shell framework setup: $installed installed, $skipped not referenced (skipped)"
    else
        ssr::log "Shell framework setup: all referenced deps already present"
    fi
}