#!/bin/bash
# Mole - File Operations
# Safe file and directory manipulation with validation

set -euo pipefail

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

# Ensure dependencies are loaded
_MOLE_CORE_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
if [[ -z "${MOLE_BASE_LOADED:-}" ]]; then
    # shellcheck source=lib/core/base.sh
    source "$_MOLE_CORE_DIR/base.sh"
fi
if [[ -z "${MOLE_LOG_LOADED:-}" ]]; then
    # shellcheck source=lib/core/log.sh
    source "$_MOLE_CORE_DIR/log.sh"
fi
if [[ -z "${MOLE_TIMEOUT_LOADED:-}" ]]; then
    # shellcheck source=lib/core/timeout.sh
    source "$_MOLE_CORE_DIR/timeout.sh"
fi

# ============================================================================
# Path Validation
# ============================================================================

# Validate path for deletion (absolute, no traversal, not system dir)
validate_path_for_deletion() {
    local path="$1"

    # Check path is not empty
    if [[ -z "$path" ]]; then
        log_error "Path validation failed: empty path"
        return 1
    fi

    # Check symlink target if path is a symbolic link
    if [[ -L "$path" ]]; then
        local link_target
        link_target=$(readlink "$path" 2> /dev/null) || {
            log_error "Cannot read symlink: $path"
            return 1
        }

        # Resolve relative symlinks to absolute paths for validation
        local resolved_target="$link_target"
        if [[ "$link_target" != /* ]]; then
            local link_dir
            link_dir=$(dirname "$path")
            resolved_target=$(cd "$link_dir" 2> /dev/null && cd "$(dirname "$link_target")" 2> /dev/null && pwd)/$(basename "$link_target") || resolved_target=""
        fi

        # Validate resolved target against protected paths
        if [[ -n "$resolved_target" ]]; then
            case "$resolved_target" in
                /System/* | /usr/bin/* | /usr/lib/* | /bin/* | /sbin/* | /private/etc/*)
                    log_error "Symlink points to protected system path: $path -> $resolved_target"
                    return 1
                    ;;
            esac
        fi
    fi

    # Check path is absolute
    if [[ "$path" != /* ]]; then
        log_error "Path validation failed: path must be absolute: $path"
        return 1
    fi

    # Check for path traversal attempts
    # Only reject .. when it appears as a complete path component (/../ or /.. or ../)
    # This allows legitimate directory names containing .. (e.g., Firefox's "name..files")
    if [[ "$path" =~ (^|/)\.\.(\/|$) ]]; then
        log_error "Path validation failed: path traversal not allowed: $path"
        return 1
    fi

    # Check path doesn't contain dangerous characters
    if [[ "$path" =~ [[:cntrl:]] ]] || [[ "$path" =~ $'\n' ]]; then
        log_error "Path validation failed: contains control characters: $path"
        return 1
    fi

    # Allow deletion of coresymbolicationd cache (safe system cache that can be rebuilt)
    case "$path" in
        /System/Library/Caches/com.apple.coresymbolicationd/data | /System/Library/Caches/com.apple.coresymbolicationd/data/*)
            return 0
            ;;
    esac

    # Allow known safe paths under /private
    case "$path" in
        /private/tmp | /private/tmp/* | \
            /private/var/tmp | /private/var/tmp/* | \
            /private/var/log | /private/var/log/* | \
            /private/var/folders | /private/var/folders/* | \
            /private/var/db/diagnostics | /private/var/db/diagnostics/* | \
            /private/var/db/DiagnosticPipeline | /private/var/db/DiagnosticPipeline/* | \
            /private/var/db/powerlog | /private/var/db/powerlog/* | \
            /private/var/db/reportmemoryexception | /private/var/db/reportmemoryexception/* | \
            /private/var/db/receipts/*.bom | /private/var/db/receipts/*.plist)
            return 0
            ;;
    esac

    # Check path isn't critical system directory
    case "$path" in
        / | /bin | /bin/* | /sbin | /sbin/* | /usr | /usr/bin | /usr/bin/* | /usr/sbin | /usr/sbin/* | /usr/lib | /usr/lib/* | /System | /System/* | /Library/Extensions)
            log_error "Path validation failed: critical system directory: $path"
            return 1
            ;;
        /private)
            log_error "Path validation failed: critical system directory: $path"
            return 1
            ;;
        /etc | /etc/* | /private/etc | /private/etc/*)
            log_error "Path validation failed: /etc contains critical system files: $path"
            return 1
            ;;
        /var | /var/db | /var/db/* | /private/var | /private/var/db | /private/var/db/*)
            log_error "Path validation failed: /var/db contains system databases: $path"
            return 1
            ;;
    esac

    # Check if path is protected (keychains, system settings, etc)
    if declare -f should_protect_path > /dev/null 2>&1; then
        if should_protect_path "$path"; then
            if [[ "${MO_DEBUG:-0}" == "1" ]]; then
                log_warning "Path validation: protected path skipped: $path"
            fi
            return 1
        fi
    fi

    return 0
}

# ============================================================================
# Safe Removal Operations
# ============================================================================

# Safe wrapper around rm -rf with validation
safe_remove() {
    local path="$1"
    local silent="${2:-false}"

    # Validate path
    if ! validate_path_for_deletion "$path"; then
        return 1
    fi

    # Check if path exists
    if [[ ! -e "$path" ]]; then
        return 0
    fi

    # Dry-run mode: log but don't delete
    if [[ "${MOLE_DRY_RUN:-0}" == "1" ]]; then
        if [[ "${MO_DEBUG:-}" == "1" ]]; then
            local file_type="file"
            [[ -d "$path" ]] && file_type="directory"
            [[ -L "$path" ]] && file_type="symlink"

            local file_size=""
            local file_age=""

            if [[ -e "$path" ]]; then
                local size_kb
                size_kb=$(get_path_size_kb "$path" 2> /dev/null || echo "0")
                if [[ "$size_kb" -gt 0 ]]; then
                    file_size=$(bytes_to_human "$((size_kb * 1024))")
                fi

                if [[ -f "$path" || -d "$path" ]] && ! [[ -L "$path" ]]; then
                    local mod_time
                    mod_time=$(stat -f%m "$path" 2> /dev/null || echo "0")
                    local now
                    now=$(date +%s 2> /dev/null || echo "0")
                    if [[ "$mod_time" -gt 0 && "$now" -gt 0 ]]; then
                        file_age=$(((now - mod_time) / 86400))
                    fi
                fi
            fi

            debug_file_action "[DRY RUN] Would remove" "$path" "$file_size" "$file_age"
        else
            debug_log "[DRY RUN] Would remove: $path"
        fi
        return 0
    fi

    debug_log "Removing: $path"

    # Perform the deletion
    # Use || to capture the exit code so set -e won't abort on rm failures
    local error_msg
    local rm_exit=0
    error_msg=$(rm -rf "$path" 2>&1) || rm_exit=$? # safe_remove

    if [[ $rm_exit -eq 0 ]]; then
        return 0
    else
        # Check if it's a permission error
        if [[ "$error_msg" == *"Permission denied"* ]] || [[ "$error_msg" == *"Operation not permitted"* ]]; then
            MOLE_PERMISSION_DENIED_COUNT=${MOLE_PERMISSION_DENIED_COUNT:-0}
            MOLE_PERMISSION_DENIED_COUNT=$((MOLE_PERMISSION_DENIED_COUNT + 1))
            export MOLE_PERMISSION_DENIED_COUNT
            debug_log "Permission denied: $path, may need Full Disk Access"
        else
            [[ "$silent" != "true" ]] && log_error "Failed to remove: $path"
        fi
        return 1
    fi
}

# Safe sudo removal with symlink protection
safe_sudo_remove() {
    local path="$1"

    # Validate path
    if ! validate_path_for_deletion "$path"; then
        log_error "Path validation failed for sudo remove: $path"
        return 1
    fi

    # Check if path exists
    if [[ ! -e "$path" ]]; then
        return 0
    fi

    # Additional check: reject symlinks for sudo operations
    if [[ -L "$path" ]]; then
        log_error "Refusing to sudo remove symlink: $path"
        return 1
    fi

    # Dry-run mode: log but don't delete
    if [[ "${MOLE_DRY_RUN:-0}" == "1" ]]; then
        if [[ "${MO_DEBUG:-}" == "1" ]]; then
            local file_type="file"
            [[ -d "$path" ]] && file_type="directory"

            local file_size=""
            local file_age=""

            if sudo test -e "$path" 2> /dev/null; then
                local size_kb
                size_kb=$(sudo du -sk "$path" 2> /dev/null | awk '{print $1}' || echo "0")
                if [[ "$size_kb" -gt 0 ]]; then
                    file_size=$(bytes_to_human "$((size_kb * 1024))")
                fi

                if sudo test -f "$path" 2> /dev/null || sudo test -d "$path" 2> /dev/null; then
                    local mod_time
                    mod_time=$(sudo stat -f%m "$path" 2> /dev/null || echo "0")
                    local now
                    now=$(date +%s 2> /dev/null || echo "0")
                    if [[ "$mod_time" -gt 0 && "$now" -gt 0 ]]; then
                        file_age=$(((now - mod_time) / 86400))
                    fi
                fi
            fi

            debug_file_action "[DRY RUN] Would remove, sudo" "$path" "$file_size" "$file_age"
        else
            debug_log "[DRY RUN] Would remove, sudo: $path"
        fi
        return 0
    fi

    debug_log "Removing, sudo: $path"

    # Perform the deletion
    if sudo rm -rf "$path" 2> /dev/null; then # SAFE: safe_sudo_remove implementation
        return 0
    else
        log_error "Failed to remove, sudo: $path"
        return 1
    fi
}

# ============================================================================
# Safe Find and Delete Operations
# ============================================================================

# Safe file discovery and deletion with depth and age limits
safe_find_delete() {
    local base_dir="$1"
    local pattern="$2"
    local age_days="${3:-7}"
    local type_filter="${4:-f}"

    # Validate base directory exists and is not a symlink
    if [[ ! -d "$base_dir" ]]; then
        log_error "Directory does not exist: $base_dir"
        return 1
    fi

    if [[ -L "$base_dir" ]]; then
        log_error "Refusing to search symlinked directory: $base_dir"
        return 1
    fi

    # Validate type filter
    if [[ "$type_filter" != "f" && "$type_filter" != "d" ]]; then
        log_error "Invalid type filter: $type_filter, must be 'f' or 'd'"
        return 1
    fi

    debug_log "Finding in $base_dir: $pattern, age: ${age_days}d, type: $type_filter"

    local find_args=("-maxdepth" "5" "-name" "$pattern" "-type" "$type_filter")
    if [[ "$age_days" -gt 0 ]]; then
        find_args+=("-mtime" "+$age_days")
    fi

    # Iterate results to respect should_protect_path
    while IFS= read -r -d '' match; do
        if should_protect_path "$match"; then
            continue
        fi
        safe_remove "$match" true || true
    done < <(command find "$base_dir" "${find_args[@]}" -print0 2> /dev/null || true)

    return 0
}

# Safe sudo discovery and deletion
safe_sudo_find_delete() {
    local base_dir="$1"
    local pattern="$2"
    local age_days="${3:-7}"
    local type_filter="${4:-f}"

    # Validate base directory (use sudo for permission-restricted dirs)
    if ! sudo test -d "$base_dir" 2> /dev/null; then
        debug_log "Directory does not exist, skipping: $base_dir"
        return 0
    fi

    if sudo test -L "$base_dir" 2> /dev/null; then
        log_error "Refusing to search symlinked directory: $base_dir"
        return 1
    fi

    # Validate type filter
    if [[ "$type_filter" != "f" && "$type_filter" != "d" ]]; then
        log_error "Invalid type filter: $type_filter, must be 'f' or 'd'"
        return 1
    fi

    debug_log "Finding, sudo, in $base_dir: $pattern, age: ${age_days}d, type: $type_filter"

    local find_args=("-maxdepth" "5" "-name" "$pattern" "-type" "$type_filter")
    if [[ "$age_days" -gt 0 ]]; then
        find_args+=("-mtime" "+$age_days")
    fi

    # Iterate results to respect should_protect_path
    while IFS= read -r -d '' match; do
        if should_protect_path "$match"; then
            continue
        fi
        safe_sudo_remove "$match" || true
    done < <(sudo find "$base_dir" "${find_args[@]}" -print0 2> /dev/null || true)

    return 0
}

# ============================================================================
# Size Calculation
# ============================================================================

# Get path size in KB (returns 0 if not found)
get_path_size_kb() {
    local path="$1"
    [[ -z "$path" || ! -e "$path" ]] && {
        echo "0"
        return
    }
    # Direct execution without timeout overhead - critical for performance in loops
    # Use || echo 0 to ensure failure in du (e.g. permission error) doesn't exit script under set -e
    # Pipefail would normally cause the pipeline to fail if du fails, but || handle catches it.
    local size
    size=$(command du -sk "$path" 2> /dev/null | awk 'NR==1 {print $1; exit}' || true)

    # Ensure size is a valid number (fix for non-numeric du output)
    if [[ "$size" =~ ^[0-9]+$ ]]; then
        echo "$size"
    else
        echo "0"
    fi
}

# Calculate total size for multiple paths
calculate_total_size() {
    local files="$1"
    local total_kb=0

    while IFS= read -r file; do
        if [[ -n "$file" && -e "$file" ]]; then
            local size_kb
            size_kb=$(get_path_size_kb "$file")
            ((total_kb += size_kb))
        fi
    done <<< "$files"

    echo "$total_kb"
}