#!/usr/bin/env bash
# install.sh — install pi-toolkit
#
# Harness-side bring-up for the pi coding-agent (https://github.com/mariozechner/pi-coding-agent):
#   - pi-env.zsh       : shell loader sourcing ~/.config/pi/.env so AWS_PROFILE
#                        and AWS_REGION are in every shell that launches pi.
#   - keybindings.json : mosh/tmux-friendly newline bindings
#                        (shift+enter, ctrl+j, alt+j).
#   - settings.example.json : template for ~/.pi/agent/settings.json so pi
#                             starts without --provider/--model. Copy + edit.
#
# No dependency on MemPalace. For the palace bridge see
# https://gitea.jordbo.se/joakimp/mempalace-toolkit (optional).
#
# Idempotent. Safe to re-run. Non-destructive on drift: if installed content
# differs from repo, leaves user edits alone and points at diff.

set -euo pipefail

# ── locate self ──────────────────────────────────────
SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

# ── targets ──────────────────────────────────────────
PI_EXT_DEST_DIR="${HOME}/.pi/agent/extensions"    # existence = pi is installed
PI_AGENT_DIR="${HOME}/.pi/agent"

# keybindings — symlinked (pi doesn't rewrite it at runtime)
PI_KEYS_SRC="${SCRIPT_DIR}/keybindings.json"
PI_KEYS_DEST="${HOME}/.pi/agent/keybindings.json"

# settings template — NOT installed, only referenced (pi rewrites settings.json)
PI_SETTINGS_EXAMPLE="${SCRIPT_DIR}/settings.example.json"
PI_SETTINGS_DEST="${HOME}/.pi/agent/settings.json"

# shell env loader — cp'd into oh-my-zsh custom dir (portability over symlink)
PI_ENV_SRC="${SCRIPT_DIR}/pi-env.zsh"
PI_ENV_OMZ_DEST="${HOME}/.oh-my-zsh/custom/pi-env.zsh"

# ── args ─────────────────────────────────────────────
ACTION="install"
ASSUME_YES="no"

while [[ $# -gt 0 ]]; do
    case "$1" in
        --uninstall) ACTION="uninstall"; shift ;;
        -y|--yes)    ASSUME_YES="yes"; shift ;;
        -h|--help)
            cat <<EOF
install.sh — install pi-toolkit

Usage:
  ./install.sh              # install (interactive confirm)
  ./install.sh --yes        # install without prompt
  ./install.sh --uninstall  # remove symlinks and copied loaders

What install does:
  - Requires pi installed (~/.pi/agent/ must exist). Aborts cleanly otherwise.
  - Symlinks keybindings.json into ~/.pi/agent/keybindings.json.
  - If oh-my-zsh is present (~/.oh-my-zsh/custom/), copies pi-env.zsh there
    so every new zsh shell sources ~/.config/pi/.env. Uses cp (not symlink)
    for dotfile-backup portability. Prints source snippet otherwise.
  - Probes (non-halting warnings): settings.json present, and AWS_PROFILE /
    AWS_REGION set if settings.json selects amazon-bedrock.

What uninstall does:
  - Removes keybindings.json symlink if it points into this repo.
  - Removes pi-env.zsh copy ONLY if its content still matches the repo.
  - Never touches settings.json (it's your file, not managed here).

No dependency on MemPalace. For memory integration see:
  https://gitea.jordbo.se/joakimp/mempalace-toolkit
EOF
            exit 0 ;;
        *) echo "Unknown flag: $1" >&2; exit 2 ;;
    esac
done

# ── helpers ──────────────────────────────────────────
ok()    { printf ' \e[32m✓\e[0m  %s\n' "$*"; }
note()  { printf '==> %s\n' "$*"; }
warn()  { printf ' \e[33m!\e[0m  %s\n' "$*" >&2; }
err()   { printf ' \e[31m✗\e[0m  %s\n' "$*" >&2; }

confirm() {
    [[ "$ASSUME_YES" == "yes" ]] && return 0
    read -r -p "Proceed? [y/N] " ans
    [[ "$ans" =~ ^[Yy]$ ]]
}

link_if_into_repo() {
    # Return 0 if $1 is a symlink pointing into $SCRIPT_DIR
    local target
    [[ -L "$1" ]] || return 1
    target=$(readlink -f "$1")
    [[ "$target" == "$SCRIPT_DIR"/* ]]
}

require_pi_installed() {
    if [[ ! -d "$PI_AGENT_DIR" ]]; then
        err "pi not detected at $PI_AGENT_DIR"
        printf '    Install pi first: https://github.com/mariozechner/pi-coding-agent\n'
        printf '    Re-run this installer after `pi` has been started at least once\n'
        printf '    (first run creates ~/.pi/agent/).\n'
        exit 4
    fi
    # Ensure the extensions dir exists so pi loads any extensions we may add
    # later (e.g. mempalace-toolkit's mempalace.ts). pi creates this on first
    # extension install but we may race ahead of that.
    mkdir -p "$PI_EXT_DEST_DIR"
    ok "pi detected at $PI_AGENT_DIR"
}

# ── install ──────────────────────────────────────────
install_keybindings() {
    # Generic mosh/tmux newline fix. Symlinked so edits flow through git.
    note "Linking keybindings.json → $PI_KEYS_DEST"
    if [[ -e "$PI_KEYS_DEST" || -L "$PI_KEYS_DEST" ]]; then
        if link_if_into_repo "$PI_KEYS_DEST"; then
            ok "pi keybindings already linked"
            return 0
        fi
        # Back up any existing real file / foreign symlink.
        local backup="${PI_KEYS_DEST}.bak.$(date +%Y%m%d-%H%M%S)"
        mv "$PI_KEYS_DEST" "$backup"
        warn "Existing $PI_KEYS_DEST backed up to $backup"
    fi
    ln -s "$PI_KEYS_SRC" "$PI_KEYS_DEST"
    ok "Linked keybindings.json → $PI_KEYS_SRC"
}

install_env_loader() {
    # Copy pi-env.zsh into ~/.oh-my-zsh/custom/ (auto-loaded by omz).
    # cp not symlink because that dir is typically part of a dotfiles backup
    # and a symlink into this repo breaks on restore to another host.
    # No oh-my-zsh → print a source snippet for manual rc-file addition.

    if [[ -d "$HOME/.oh-my-zsh/custom" ]]; then
        note "Installing pi-env.zsh into ~/.oh-my-zsh/custom/"
        if [[ -f "$PI_ENV_OMZ_DEST" ]]; then
            if cmp -s "$PI_ENV_SRC" "$PI_ENV_OMZ_DEST"; then
                ok "pi-env.zsh already installed (content matches repo)"
                return 0
            fi
            warn "$PI_ENV_OMZ_DEST exists and differs from repo copy"
            printf '       Leaving your edits alone. Compare with:\n'
            printf '           diff %q %q\n' "$PI_ENV_OMZ_DEST" "$PI_ENV_SRC"
            printf '       To adopt the repo version: rm that file and re-run install.sh\n'
            return 0
        fi
        cp "$PI_ENV_SRC" "$PI_ENV_OMZ_DEST"
        ok "Copied pi-env.zsh → $PI_ENV_OMZ_DEST"
        printf '       Open a new shell (or `exec zsh`) to load AWS_PROFILE / AWS_REGION.\n'
        return 0
    fi

    # No oh-my-zsh — print shell-specific snippet.
    note "oh-my-zsh not detected — manual shell setup needed"
    local shell_name
    shell_name="$(basename "${SHELL:-bash}")"
    local rc_file
    case "$shell_name" in
        zsh)  rc_file="~/.zshrc" ;;
        bash) rc_file="~/.bashrc" ;;
        *)    rc_file="~/.${shell_name}rc  # adjust for your shell" ;;
    esac
    printf '       Add this line to %s so every shell sources ~/.config/pi/.env:\n' "$rc_file"
    printf '           source %q\n' "$PI_ENV_SRC"
    printf '       (the loader itself is POSIX-compatible — works in bash and zsh.)\n'
}

# ── Probes ───────────────────────────────────────────
# Never halt. warn + return 0 — mirrors opencode-toolkit and mempalace-toolkit.
check_pi_settings() {
    # If settings.json missing, pi refuses to start without --provider/--model
    # on every run. Template exists in this repo; point at the cp command.
    if [[ -f "$PI_SETTINGS_DEST" ]]; then
        ok "pi settings.json present at $PI_SETTINGS_DEST"
        return 0
    fi

    warn "pi settings.json NOT found at $PI_SETTINGS_DEST"
    printf '       Without it, pi must be invoked with --provider/--model every run.\n'
    printf '       Bootstrap from the shipped template:\n'
    printf '           cp %q %q\n' "$PI_SETTINGS_EXAMPLE" "$PI_SETTINGS_DEST"
    printf '           $EDITOR %q   # adjust region prefix + model IDs\n' "$PI_SETTINGS_DEST"
    printf '       See README.md for the eu./us./anthropic: prefix rules.\n'
}

check_aws_env() {
    # Only warn if settings.json selects amazon-bedrock. If pi uses a
    # non-Bedrock provider (bare anthropic, openai, ...) AWS creds are
    # irrelevant and this probe would be noise. If settings.json doesn't
    # exist yet, check_pi_settings already told the user to bootstrap it
    # — we can't know which provider they'll pick, so stay quiet here.
    [[ -f "$PI_SETTINGS_DEST" ]] || return 0
    grep -q '"amazon-bedrock"' "$PI_SETTINGS_DEST" 2>/dev/null || return 0

    if [[ -n "${AWS_PROFILE:-}" && -n "${AWS_REGION:-}" ]]; then
        ok "AWS env present (AWS_PROFILE=$AWS_PROFILE, AWS_REGION=$AWS_REGION)"
        return 0
    fi

    warn "AWS_PROFILE and/or AWS_REGION not set in this shell"
    printf '       pi with defaultProvider=amazon-bedrock needs both to invoke Bedrock.\n'
    printf '       Recommended layout (matches tor-ms22 dotfiles pattern):\n'
    printf '           ~/.config/pi/.env              # AWS_PROFILE=..., AWS_REGION=...\n'
    printf '       The pi-env.zsh loader (installed above) sources it automatically.\n'
    printf '       Open a fresh shell to pick up the vars after creating the file.\n'
}

do_install() {
    echo
    echo "pi-toolkit installer"
    echo "Repository: $SCRIPT_DIR"
    echo
    require_pi_installed
    echo
    echo "==> Installation plan:"
    echo "   Symlink keybindings.json → $PI_KEYS_DEST"
    if [[ -d "$HOME/.oh-my-zsh/custom" ]]; then
        echo "   Copy pi-env.zsh → $PI_ENV_OMZ_DEST"
    else
        echo "   Print manual source-snippet instructions for pi-env.zsh"
    fi
    echo
    confirm || { echo "Aborted."; exit 0; }
    echo
    install_keybindings
    echo
    install_env_loader
    echo
    check_pi_settings
    echo
    check_aws_env
    echo
    ok "Done."
}

# ── uninstall ────────────────────────────────────────
do_uninstall() {
    echo
    echo "pi-toolkit uninstaller"
    echo "Repository: $SCRIPT_DIR"
    echo
    confirm || { echo "Aborted."; exit 0; }
    echo

    note "Removing pi keybindings symlink"
    if link_if_into_repo "$PI_KEYS_DEST"; then
        rm "$PI_KEYS_DEST"
        ok "Removed pi keybindings symlink"
    else
        ok "No pi keybindings symlink to remove"
    fi

    echo
    note "Removing pi-env.zsh loader (oh-my-zsh path)"
    # Only remove if content still matches the repo copy — user may have
    # local edits we shouldn't silently discard.
    if [[ -f "$PI_ENV_OMZ_DEST" ]] && cmp -s "$PI_ENV_SRC" "$PI_ENV_OMZ_DEST"; then
        rm "$PI_ENV_OMZ_DEST"
        ok "Removed $PI_ENV_OMZ_DEST"
    elif [[ -f "$PI_ENV_OMZ_DEST" ]]; then
        warn "$PI_ENV_OMZ_DEST differs from repo copy — left alone"
    else
        ok "No pi-env.zsh loader to remove"
    fi

    echo
    ok "Done."
}

case "$ACTION" in
    install)   do_install ;;
    uninstall) do_uninstall ;;
esac