module gg

import os

enum ScreenshotOutput {
    file
    stdout
}

const gg_record_stdout_prefix = '__V_GG_IMAGE__'

@[heap]
pub struct SSRecorderSettings {
pub mut:
    stop_at_frame     i64 = -1
    screenshot_frames []u64
    screenshot_folder string
    screenshot_prefix string
    screenshot_output ScreenshotOutput = .file
}

fn parse_screenshot_frames(value string) []u64 {
    mut frames := []u64{}
    for raw_frame in value.split(',') {
        frame := raw_frame.trim_space()
        if frame == '' {
            continue
        }
        frames << frame.u64()
    }
    return frames
}

fn parse_screenshot_output(value string) ScreenshotOutput {
    return match value.trim_space().to_lower() {
        'stdout' { .stdout }
        else { .file }
    }
}

fn recorder_env_value(env map[string]string, key string, fallback string) string {
    value := env[key]
    if value == '' {
        return fallback
    }
    return value
}

fn new_gg_recorder_settings_from_env(env map[string]string, executable string) &SSRecorderSettings {
    mut stop_frame := recorder_env_value(env, 'VGG_STOP_AT_FRAME', '-1').i64()
    mut frames := parse_screenshot_frames(env['VGG_SCREENSHOT_FRAMES'])
    folder := env['VGG_SCREENSHOT_FOLDER']
    output := parse_screenshot_output(env['VGG_SCREENSHOT_OUTPUT'])
    if output == .stdout && frames.len == 0 {
        frames << u64(1)
    }
    if output == .stdout && stop_frame < 0 && frames.len > 0 {
        stop_frame = i64(frames[frames.len - 1])
    }
    prefix := os.join_path_single(folder, os.file_name(executable).all_before('.') + '_')
    return &SSRecorderSettings{
        stop_at_frame:     stop_frame
        screenshot_frames: frames
        screenshot_folder: folder
        screenshot_prefix: prefix
        screenshot_output: output
    }
}