#!/usr/bin/env bash
# Shared Git Utilities
# Sprint: CI/CD Enhancement - Script Consolidation
#
# Purpose: Common git operations for CI/CD scripts
# Usage: source "$(dirname "${BASH_SOURCE[0]}")/lib/git-utils.sh"

# Prevent multiple sourcing
if [[ -n "${__STELLAOPS_GIT_UTILS_LOADED:-}" ]]; then
    return 0
fi
export __STELLAOPS_GIT_UTILS_LOADED=1

# Source dependencies
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
source "${SCRIPT_DIR}/logging.sh" 2>/dev/null || true
source "${SCRIPT_DIR}/exit-codes.sh" 2>/dev/null || true

# ============================================================================
# Repository Information
# ============================================================================

# Get repository root directory
git_root() {
    git rev-parse --show-toplevel 2>/dev/null || echo "."
}

# Check if current directory is a git repository
is_git_repo() {
    git rev-parse --git-dir >/dev/null 2>&1
}

# Get current commit SHA (full)
git_sha() {
    git rev-parse HEAD 2>/dev/null
}

# Get current commit SHA (short)
git_sha_short() {
    git rev-parse --short HEAD 2>/dev/null
}

# Get current branch name
git_branch() {
    git rev-parse --abbrev-ref HEAD 2>/dev/null
}

# Get current tag (if HEAD is tagged)
git_tag() {
    git describe --tags --exact-match HEAD 2>/dev/null || echo ""
}

# Get latest tag
git_latest_tag() {
    git describe --tags --abbrev=0 2>/dev/null || echo ""
}

# Get remote URL
git_remote_url() {
    local remote="${1:-origin}"
    git remote get-url "$remote" 2>/dev/null
}

# Get repository name from remote URL
git_repo_name() {
    local url
    url=$(git_remote_url "${1:-origin}")
    basename "$url" .git
}

# ============================================================================
# Commit Information
# ============================================================================

# Get commit message
git_commit_message() {
    local sha="${1:-HEAD}"
    git log -1 --format="%s" "$sha" 2>/dev/null
}

# Get commit author
git_commit_author() {
    local sha="${1:-HEAD}"
    git log -1 --format="%an" "$sha" 2>/dev/null
}

# Get commit author email
git_commit_author_email() {
    local sha="${1:-HEAD}"
    git log -1 --format="%ae" "$sha" 2>/dev/null
}

# Get commit timestamp (ISO 8601)
git_commit_timestamp() {
    local sha="${1:-HEAD}"
    git log -1 --format="%aI" "$sha" 2>/dev/null
}

# Get commit timestamp (Unix epoch)
git_commit_epoch() {
    local sha="${1:-HEAD}"
    git log -1 --format="%at" "$sha" 2>/dev/null
}

# ============================================================================
# Working Tree State
# ============================================================================

# Check if working tree is clean
git_is_clean() {
    [[ -z "$(git status --porcelain 2>/dev/null)" ]]
}

# Check if working tree is dirty
git_is_dirty() {
    ! git_is_clean
}

# Get list of changed files
git_changed_files() {
    git status --porcelain 2>/dev/null | awk '{print $2}'
}

# Get list of staged files
git_staged_files() {
    git diff --cached --name-only 2>/dev/null
}

# Get list of untracked files
git_untracked_files() {
    git ls-files --others --exclude-standard 2>/dev/null
}

# ============================================================================
# Diff and History
# ============================================================================

# Get files changed between two refs
git_diff_files() {
    local from="${1:-HEAD~1}"
    local to="${2:-HEAD}"
    git diff --name-only "$from" "$to" 2>/dev/null
}

# Get files changed in last N commits
git_recent_files() {
    local count="${1:-1}"
    git diff --name-only "HEAD~${count}" HEAD 2>/dev/null
}

# Check if file was changed between two refs
git_file_changed() {
    local file="$1"
    local from="${2:-HEAD~1}"
    local to="${3:-HEAD}"
    git diff --name-only "$from" "$to" -- "$file" 2>/dev/null | grep -q "$file"
}

# Get commits between two refs
git_commits_between() {
    local from="${1:-HEAD~10}"
    local to="${2:-HEAD}"
    git log --oneline "$from".."$to" 2>/dev/null
}

# ============================================================================
# Tag Operations
# ============================================================================

# Create a tag
git_create_tag() {
    local tag="$1"
    local message="${2:-}"

    if [[ -n "$message" ]]; then
        git tag -a "$tag" -m "$message"
    else
        git tag "$tag"
    fi
}

# Delete a tag
git_delete_tag() {
    local tag="$1"
    git tag -d "$tag" 2>/dev/null
}

# Push tag to remote
git_push_tag() {
    local tag="$1"
    local remote="${2:-origin}"
    git push "$remote" "$tag"
}

# List tags matching pattern
git_list_tags() {
    local pattern="${1:-*}"
    git tag -l "$pattern" 2>/dev/null
}

# ============================================================================
# Branch Operations
# ============================================================================

# Check if branch exists
git_branch_exists() {
    local branch="$1"
    git show-ref --verify --quiet "refs/heads/$branch" 2>/dev/null
}

# Check if remote branch exists
git_remote_branch_exists() {
    local branch="$1"
    local remote="${2:-origin}"
    git show-ref --verify --quiet "refs/remotes/$remote/$branch" 2>/dev/null
}

# Get default branch
git_default_branch() {
    local remote="${1:-origin}"
    git remote show "$remote" 2>/dev/null | grep "HEAD branch" | awk '{print $NF}'
}

# ============================================================================
# CI/CD Helpers
# ============================================================================

# Get version string for CI builds
git_ci_version() {
    local tag
    tag=$(git_tag)

    if [[ -n "$tag" ]]; then
        echo "$tag"
    else
        local branch sha
        branch=$(git_branch | tr '/' '-')
        sha=$(git_sha_short)
        echo "${branch}-${sha}"
    fi
}

# Check if current commit is on default branch
git_is_default_branch() {
    local current default
    current=$(git_branch)
    default=$(git_default_branch)
    [[ "$current" == "$default" ]]
}

# Check if running in CI environment
git_is_ci() {
    [[ -n "${CI:-}" ]] || [[ -n "${GITHUB_ACTIONS:-}" ]] || [[ -n "${GITLAB_CI:-}" ]]
}

# Ensure clean worktree or fail
git_require_clean() {
    if git_is_dirty; then
        log_error "Working tree is dirty. Commit or stash changes first."
        return "${EXIT_DIRTY_WORKTREE:-71}"
    fi
}