using GoogleApi.Entities.Search.Video.Common;
using Microsoft.AspNetCore.Mvc;
using System.Text.Json;
using System.Text.RegularExpressions;
using TIAMWebApp.Shared.Application.Models;


namespace TIAMWebApp.Server.Controllers
{

    [ApiController]
    [Route("api/blog")]
    public class BlogAPIController : ControllerBase
    {
        private readonly IWebHostEnvironment _env;
        private readonly string _dataPath;
        private readonly string _coverPath;

        public BlogAPIController(IWebHostEnvironment env)
        {
            _env = env;
            _dataPath = Path.Combine(_env.WebRootPath, "data");
            _coverPath = Path.Combine(_env.WebRootPath, "uploads", "covers");
            Directory.CreateDirectory(_dataPath);
            Directory.CreateDirectory(_coverPath);
        }

        // ✅ Get All Posts
        [HttpGet]
        public IActionResult GetAll()
        {
            var files = Directory.GetFiles(_dataPath, "*.json");
            var posts = files.Select(file =>
            {
                var json = System.IO.File.ReadAllText(file);
                return JsonSerializer.Deserialize<BlogPostMetadata>(json);
            }).ToList();

            return Ok(posts);
        }

        // ✅ Get Single Post
        [HttpGet("{id}")]
        public IActionResult GetById(string id)
        {
            var file = Path.Combine(_dataPath, $"{id}.json");
            if (!System.IO.File.Exists(file))
                return NotFound();

            var json = System.IO.File.ReadAllText(file);
            var post = JsonSerializer.Deserialize<BlogPostMetadata>(json);
            return Ok(post);
        }

        // ✅ Create Post (with optional cover upload)
        [HttpPost]
        public async Task<IActionResult> Create([FromForm] BlogPostForm form)
        {
            var post = new BlogPostMetadata
            {
                Title = form.Title,
                Lead = form.Lead,
                DriveLink = form.DriveLink,
                Tags = form.Tags.Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries).ToList()
            };

            if (form.CoverImage != null)
            {
                string fileName = $"{post.Id}{Path.GetExtension(form.CoverImage.FileName)}";
                string filePath = Path.Combine(_coverPath, fileName);
                await using var fs = System.IO.File.Create(filePath);
                await form.CoverImage.CopyToAsync(fs);
                post.CoverImage = $"/uploads/covers/{fileName}";
            }

            string jsonPath = Path.Combine(_dataPath, $"{post.Id}.json");
            await System.IO.File.WriteAllTextAsync(jsonPath, JsonSerializer.Serialize(post));

            return Ok(post);
        }

        //// ✅ Update Post
        //[HttpPut("{id}")]
        //public async Task<IActionResult> Update(string id, [FromBody] BlogPostMetadata post)
        //{
        //    string jsonPath = Path.Combine(_dataPath, $"{id}.json");
        //    if (!System.IO.File.Exists(jsonPath))
        //        return NotFound();

        //    post.Id = id; // Ensure correct ID
        //    await System.IO.File.WriteAllTextAsync(jsonPath, JsonSerializer.Serialize(post));
        //    return Ok(post);
        //}

        [HttpPut("{id}")]
        public async Task<IActionResult> Update(string id)
        {
            var form = await Request.ReadFormAsync();

            // Parse metadata fields
            var title = form["Title"].ToString();
            var lead = form["Lead"].ToString();
            var tags = form["Tags"].ToString().Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries).ToList();
            var driveLink = form["DriveLink"].ToString();

            string coverImagePath = null;
            var file = form.Files.GetFile("CoverImage");

            if (file != null)
            {
                var ext = Path.GetExtension(file.FileName);
                var fileName = $"{id}{ext}";
                var filePath = Path.Combine(_coverPath, fileName);

                using var stream = System.IO.File.Create(filePath);
                await file.CopyToAsync(stream);

                // Save relative path
                coverImagePath = $"/uploads/covers/{fileName}";
            }

            // Load existing metadata
            string jsonPath = Path.Combine(_dataPath, $"{id}.json");
            if (!System.IO.File.Exists(jsonPath))
                return NotFound();

            var existingJson = await System.IO.File.ReadAllTextAsync(jsonPath);
            var existing = JsonSerializer.Deserialize<BlogPostMetadata>(existingJson);

            // Update values
            existing.Title = title;
            existing.Lead = lead;
            existing.Tags = tags;
            existing.DriveLink = driveLink;
            existing.CoverImage = coverImagePath;

            if (!string.IsNullOrWhiteSpace(coverImagePath))
                existing.CoverImage = coverImagePath;

            await System.IO.File.WriteAllTextAsync(jsonPath, JsonSerializer.Serialize(existing));
            return Ok(existing);
        }


        // ✅ Delete Post
        [HttpDelete("{id}")]
        public IActionResult Delete(string id)
        {
            string jsonPath = Path.Combine(_dataPath, $"{id}.json");
            if (!System.IO.File.Exists(jsonPath))
                return NotFound();

            var post = JsonSerializer.Deserialize<BlogPostMetadata>(System.IO.File.ReadAllText(jsonPath));
            if (!string.IsNullOrEmpty(post?.CoverImage))
            {
                var coverPath = Path.Combine(_env.WebRootPath, post.CoverImage.TrimStart('/').Replace("/", Path.DirectorySeparatorChar.ToString()));
                if (System.IO.File.Exists(coverPath))
                    System.IO.File.Delete(coverPath);
            }

            System.IO.File.Delete(jsonPath);
            return NoContent();
        }

        [HttpGet("postcontent/{postId}")]
        public async Task<IActionResult> GetPostContent(string postId)
        {
            // Load metadata (adjust this to your actual metadata loading logic)
            var metadataPath = Path.Combine(_dataPath, $"{postId}.json");
            if (!System.IO.File.Exists(metadataPath))
            {
                return NotFound("Post metadata not found.");
            }

            var metadataJson = await System.IO.File.ReadAllTextAsync(metadataPath);
            var metadata = System.Text.Json.JsonSerializer.Deserialize<BlogPostMetadata>(metadataJson);
            if (metadata == null || string.IsNullOrEmpty(metadata.DriveLink))
            {
                return BadRequest("Invalid post metadata.");
            }

            // Extract file ID from Google Drive link
            string? fileId = ExtractGoogleDriveFileId(metadata.DriveLink);
            if (string.IsNullOrEmpty(fileId))
            {
                return BadRequest("Invalid Drive link.");
            }

            // Download blog content from Drive
            string downloadUrl = $"https://drive.google.com/uc?export=download&id={fileId}";
            using var httpClient = new HttpClient();
            var content = await httpClient.GetStringAsync(downloadUrl);

            return Content(content, "text/html");
        }

        private string? ExtractGoogleDriveFileId(string driveLink)
        {
            var match = Regex.Match(driveLink, @"\/d\/([^\/]+)");
            return match.Success ? match.Groups[1].Value : null;
        }

        public class BlogPostForm
        {
            public string Title { get; set; }
            public string Lead { get; set; }
            public string DriveLink { get; set; }
            public string Tags { get; set; }
            public IFormFile CoverImage { get; set; }
        }
    }
}