HtmlToPdf/mvp/HtmlToPdfService.Api/Controllers/ImageController.cs

using Microsoft.AspNetCore.Mvc;
using PuppeteerSharp;
using HtmlToPdfService.Api.Models;
using HtmlToPdfService.Core.Services;
using HtmlToPdfService.Core.Storage;

namespace HtmlToPdfService.Api.Controllers;

/// <summary>
/// 图片转换控制器
/// </summary>
[ApiController]
[Route("api/image")]
public class ImageController : ControllerBase
{
    private readonly IImageService _imageService;
    private readonly IFileStorage _fileStorage;
    private readonly ILogger<ImageController> _logger;

    public ImageController(
        IImageService imageService,
        IFileStorage fileStorage,
        ILogger<ImageController> logger)
    {
        _imageService = imageService;
        _fileStorage = fileStorage;
        _logger = logger;
    }

    /// <summary>
    /// 从 HTML 内容生成图片
    /// </summary>
    [HttpPost("convert/html")]
    [ProducesResponseType(typeof(FileContentResult), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status400BadRequest)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status500InternalServerError)]
    public async Task<IActionResult> ConvertHtml(
        [FromBody] ConvertHtmlToImageRequest request,
        CancellationToken cancellationToken)
    {
        if (!ModelState.IsValid)
        {
            return BadRequest(ModelState);
        }

        try
        {
            _logger.LogInformation("收到 HTML 转图片请求");

            // 构建截图选项
            var screenshotOptions = BuildScreenshotOptions(request.Options);

            // 执行转换
            var result = await _imageService.ConvertHtmlToImageAsync(
                request.Html,
                screenshotOptions,
                request.Options?.Width,
                request.Options?.Height,
                request.DelayAfterLoad,
                request.Callback?.Url,
                request.Callback?.Headers,
                request.Callback?.IncludePdfData,
                request.SaveLocal,
                cancellationToken);

            // 返回图片文件
            var contentType = GetContentType(request.Options?.Format);
            var fileName = $"screenshot.{request.Options?.Format ?? "png"}";
            
            return File(result.PdfData!, contentType, fileName);
        }
        catch (ArgumentException ex)
        {
            _logger.LogWarning(ex, "请求参数无效");
            return BadRequest(new ProblemDetails
            {
                Status = StatusCodes.Status400BadRequest,
                Title = "请求参数无效",
                Detail = ex.Message
            });
        }
        catch (TimeoutException ex)
        {
            _logger.LogError(ex, "转换超时");
            return StatusCode(StatusCodes.Status503ServiceUnavailable, new ProblemDetails
            {
                Status = StatusCodes.Status503ServiceUnavailable,
                Title = "服务繁忙",
                Detail = ex.Message
            });
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "HTML 转图片失败");
            return StatusCode(StatusCodes.Status500InternalServerError, new ProblemDetails
            {
                Status = StatusCodes.Status500InternalServerError,
                Title = "转换失败",
                Detail = ex.Message
            });
        }
    }

    /// <summary>
    /// 从 URL 生成图片
    /// </summary>
    [HttpPost("convert/url")]
    [ProducesResponseType(typeof(FileContentResult), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status400BadRequest)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status500InternalServerError)]
    public async Task<IActionResult> ConvertUrl(
        [FromBody] ConvertUrlToImageRequest request,
        CancellationToken cancellationToken)
    {
        if (!ModelState.IsValid)
        {
            return BadRequest(ModelState);
        }

        try
        {
            _logger.LogInformation("收到 URL 转图片请求: {Url}", request.Url);

            // 构建截图选项
            var screenshotOptions = BuildScreenshotOptions(request.Options);

            // 解析等待条件
            WaitUntilNavigation[]? waitUntil = null;
            if (!string.IsNullOrEmpty(request.WaitUntil))
            {
                waitUntil = ParseWaitUntil(request.WaitUntil);
            }

            // 执行转换
            var result = await _imageService.ConvertUrlToImageAsync(
                request.Url,
                screenshotOptions,
                request.Options?.Width,
                request.Options?.Height,
                waitUntil,
                request.Timeout,
                request.DelayAfterLoad,
                request.Callback?.Url,
                request.Callback?.Headers,
                request.Callback?.IncludePdfData,
                request.SaveLocal,
                cancellationToken);

            // 返回图片文件
            var contentType = GetContentType(request.Options?.Format);
            var fileName = $"screenshot.{request.Options?.Format ?? "png"}";
            
            return File(result.PdfData!, contentType, fileName);
        }
        catch (ArgumentException ex)
        {
            _logger.LogWarning(ex, "请求参数无效");
            return BadRequest(new ProblemDetails
            {
                Status = StatusCodes.Status400BadRequest,
                Title = "请求参数无效",
                Detail = ex.Message
            });
        }
        catch (TimeoutException ex)
        {
            _logger.LogError(ex, "转换超时");
            return StatusCode(StatusCodes.Status503ServiceUnavailable, new ProblemDetails
            {
                Status = StatusCodes.Status503ServiceUnavailable,
                Title = "服务繁忙",
                Detail = ex.Message
            });
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "URL 转图片失败");
            return StatusCode(StatusCodes.Status500InternalServerError, new ProblemDetails
            {
                Status = StatusCodes.Status500InternalServerError,
                Title = "转换失败",
                Detail = ex.Message
            });
        }
    }

    /// <summary>
    /// 构建截图选项
    /// </summary>
    private ScreenshotOptions BuildScreenshotOptions(ImageOptionsDto? options)
    {
        if (options == null)
        {
            return new ScreenshotOptions { FullPage = true };
        }

        var screenshotOptions = new ScreenshotOptions
        {
            FullPage = options.FullPage,
            Type = ParseScreenshotType(options.Format),
            OmitBackground = options.OmitBackground ?? false
        };

        // JPEG 和 WebP 支持质量设置
        if (options.Quality.HasValue && 
            (screenshotOptions.Type == ScreenshotType.Jpeg || screenshotOptions.Type == ScreenshotType.Webp))
        {
            screenshotOptions.Quality = options.Quality.Value;
        }

        // 如果指定了截图区域
        if (options.Clip != null)
        {
            screenshotOptions.Clip = new PuppeteerSharp.Media.Clip
            {
                X = options.Clip.X,
                Y = options.Clip.Y,
                Width = options.Clip.Width,
                Height = options.Clip.Height
            };
        }

        return screenshotOptions;
    }

    /// <summary>
    /// 解析截图类型
    /// </summary>
    private ScreenshotType ParseScreenshotType(string? format)
    {
        return format?.ToLowerInvariant() switch
        {
            "jpeg" or "jpg" => ScreenshotType.Jpeg,
            "webp" => ScreenshotType.Webp,
            _ => ScreenshotType.Png
        };
    }

    /// <summary>
    /// 获取 Content-Type
    /// </summary>
    private string GetContentType(string? format)
    {
        return format?.ToLowerInvariant() switch
        {
            "jpeg" or "jpg" => "image/jpeg",
            "webp" => "image/webp",
            _ => "image/png"
        };
    }

    /// <summary>
    /// 解析等待条件
    /// </summary>
    private WaitUntilNavigation[] ParseWaitUntil(string waitUntil)
    {
        return waitUntil.ToLowerInvariant() switch
        {
            "load" => new[] { WaitUntilNavigation.Load },
            "domcontentloaded" => new[] { WaitUntilNavigation.DOMContentLoaded },
            "networkidle0" => new[] { WaitUntilNavigation.Networkidle0 },
            "networkidle2" => new[] { WaitUntilNavigation.Networkidle2 },
            _ => new[] { WaitUntilNavigation.Networkidle2 }
        };
    }
}