#!/usr/bin/env bash

# SPDX-License-Identifier: Apache-2.0
# Source: https://github.com/loverdos/pre-commit

# shellcheck disable=SC2034
SCRIPT_VERSION=16

# shellcheck disable=SC2034
SCRIPT_ID=AF13AE47-34E0-41FA-8FF8-AF660A922C6A

# Requirements: recent `bash`, `curl`, `git`, and some other general utilities.
# On macOS the built-in `bash` may not work, so install from `brew`.
# Tested-on: macOS, Linux
# Tested-on: fish, bash

# Manages the `git` pre-commit hook.
# The script serves both as an installer for itself and a hook runner.
#
# To install, you need to be in a `git` working tree already, and run
# the following:
#
#   curl -fsSL https://raw.githubusercontent.com/loverdos/pre-commit/main/pre-commit -o pre-commit && chmod +x pre-commit && ./pre-commit --install
#
# Of course, you have the opportunity to first inspect the downloaded file and then execute it.
#
# This does the following:
#   - Creates a `.pre-commit/` folder in the repo, and places the downloaded script there.
#     A pre-existing `.pre-commit/pre-commit` is backed up in `.pre-commit/`
#   - Makes sure that `.git/hooks/pre-commit` links to the above.
#     A pre-existing `.git/hooks/pre-commit` is backed up in `.git/hooks`.
#
# In the `.pre-commit` folder you place the scripts to run before any `git commit`.
# Apparently, none of them should be named `pre-commit`.
# That's it.
#
# Developing the script itself:
#   1. # ... make changes
#   2. ./pre-commit --install
#   3. git commit -m 'new version'
#
# We assume `shellcheck` is installed.

set -euo pipefail

MY_URL=https://raw.githubusercontent.com/loverdos/pre-commit/main/pre-commit
MY_PATH="$0"

pre_commit=pre-commit

org=loverdos
repo=$pre_commit

dot_pre_commit=.$pre_commit
dot_pre_commit_pre_commit=$dot_pre_commit/$pre_commit

dot_git_hooks=.git/hooks
dot_git_hooks_pre_commit=$dot_git_hooks/$pre_commit

dot_script_id=.script_id

function LOG() {
    echo "== $*" >&2
}

# We must always be in a git work tree.
git_root=$(git rev-parse --show-toplevel 2>/dev/null) || {
    LOG "Error: $(pwd) is not a Git work tree"
    exit 1
}

function is_it_me() {
    [[ -f $dot_script_id ]] && [[ $(<"$dot_script_id") == "$SCRIPT_ID" ]] && {
        # remote=$(git remote get-url origin)
        # [[ $remote == https://github.com/$org/$repo.git || $remote == [email protected]:$org/$repo.git ]]
        true
    }
}

function mk_id() {
    echo "$(date -u +%F).$$.$RANDOM"
}

function is_file_or_link() {
    [[ -f "$1" || -L "$1" ]]
}

function is_tracked_in_git() {
    git ls-files --error-unmatch "$1" >/dev/null 2>&1
}

function backup_file() {
    file="$1"
    [[ -z "$2" ]] && suffix=$(mk_id) || suffix="$2"

    new_location="$file.$suffix"

    LOG "Backing up $file to $new_location"

    mv "$file" "$new_location"
}

function sec_to_mmss() {
    local time_sec=$1
    local time_min=$((time_sec / 60))
    time_sec=$((time_sec % 60))

    printf "%02d:%02d" $time_min $time_sec
}

function install() {
    LOG "Begin installation process from $MY_PATH to $git_root"

    if [[ "$MY_PATH" == /dev/*/* ]]; then
        # We use the previous installation method:
        #   bash -c "bash <(curl -fsSL https://raw.githubusercontent.com/loverdos/pre-commit/main/pre-commit) --install"
        # which will not work.

        LOG "You appear to be installing using the old installation recipe"
        LOG "  

  

    

      pre-commit/pre-commit
    
    

         Line 23
      in
      fdfb0a7
    
  
  

    


        

          

          
 #   bash <(curl -fsSL https://raw.githubusercontent.com/loverdos/pre-commit/main/pre-commit) --install 
        
    
  

"
        LOG "which is not compatible with newer versions of the script"
        LOG ""
        LOG "Please use the newer installation method."

        return 2
    fi

    cd "$git_root"

    local script=$dot_pre_commit_pre_commit

    local script_exists=0
    is_file_or_link $script && script_exists=1 # normally it should not be a link ...

    local script_is_tracked=0
    is_tracked_in_git $script && script_is_tracked=1

    if ((script_is_tracked == 1)); then
        LOG "$script exists and is tracked by git"
    elif ((script_exists == 1)); then
        LOG "$script exists and is not being tracked by git"
    else
        LOG "$script does not exist, first time installation"
    fi

    # Make sure all the needed folders exist
    mkdir -p $dot_pre_commit
    mkdir -p $dot_git_hooks

    # Back up the previous version and install the new one.
    backup_id=$(mk_id)
    if ((script_is_tracked == 0 && script_exists == 1)); then
        backup_file $script "$backup_id"
    fi

    if is_it_me; then
        cp "$MY_PATH" $script
    else
        mv "$MY_PATH" $script
    fi

    # Back up the hook and install the new one
    if is_file_or_link $dot_git_hooks_pre_commit; then
        backup_file $dot_git_hooks_pre_commit "$backup_id"
    fi
    ln -s "$git_root"/$script $dot_git_hooks_pre_commit

    LOG "Installed version: $SCRIPT_VERSION "
    LOG "               of: $MY_URL"
    LOG "               to: $script"
    LOG "End installation process from $MY_PATH to $git_root"
}

function run() {
    local cmds=()
    local cmd_statuses=()
    local successes=0
    local failures=0
    local mark=""
    local script_seconds=0
    local script_time=""
    local script_times=()

    LOG "Running pre-commit hook"
    SECONDS=0 # bash builtin ;)

    cd "$git_root"

    set +e
    for script in "$dot_pre_commit"/*; do
        # We do not want to run ourselves recursively ...
        if [[ "$script" == "$dot_pre_commit_pre_commit" || "$script" == "$dot_pre_commit_pre_commit".* ]]; then
            continue
        fi

        LOG
        LOG "Run: $script"

        script_seconds=$SECONDS
        
        $script
        status=$?
        
        script_seconds=$((SECONDS - script_seconds))

        cmds+=("$script")
        cmd_statuses+=("$status")

        script_time=$(sec_to_mmss $script_seconds)
        script_times+=("$script_time")

        if ((status == 0)); then
            ((successes++))
            mark="✅"
        else
            ((failures++))
            mark="❌"
        fi

        LOG "Exit: $mark [= $status] $script"
    done
    set -e

    time=$(sec_to_mmss $SECONDS)

    LOG
    LOG "Results: $successes success(es), $failures failure(s)"
    LOG "     In: $time [min:sec]"
    LOG

    local result=0

    for i in "${!cmds[@]}"; do
        if ((cmd_statuses[i] == 0)); then
            LOG "✅ [${script_times[i]}] ${cmds[i]}"
        else
            LOG "❌ [${script_times[i]}] ${cmds[i]}"
            result=1
        fi
    done

    LOG

    return $result
}

# Install ourselves if that is what was requested.
if [[ $# -eq 1 && $1 == "--install" ]]; then
    install
else
    run
fi