using System.Net;
using System.Net.Http.Json;
using System.Text.Json;

namespace WordVersioning.Api.IntegrationTests;

/// <summary>FR-9 — template CRUD + auto-detect SDT tags ตอน upload/replace ไฟล์ (AC-11 ส่วน backend)</summary>
[Collection(IntegrationTestCollection.Name)]
public sealed class TemplateTests(IntegrationTestFixture fixture)
{
    /// <summary>สร้าง template จาก BuildTemplateDocx() — คืน (id, fields ที่ detect ได้) — ใช้ร่วมกับ test อื่น</summary>
    public static async Task<(Guid TemplateId, List<TemplateFieldItem> Fields)> CreateDefaultTemplateAsync(
        HttpClient client, string name)
    {
        using var response = await client.PostAsync(
            "api/templates", ApiExtensions.TemplateForm(TestDocx.BuildTemplateDocx(), name));
        Assert.Equal(HttpStatusCode.Created, response.StatusCode);
        var result = await response.Content.ReadFromJsonAsync<CreateTemplateResult>(IntegrationTestFixture.Json);
        return (result!.Id, result.Fields);
    }

    [Fact]
    public async Task Create_DetectsAllSdtTags_WithDefaults()
    {
        using var client = fixture.CreateClient();
        var (templateId, fields) = await CreateDefaultTemplateAsync(client, $"สัญญา {Guid.NewGuid():N}");

        // 5 tags ในไฟล์ (employee_name ซ้ำ 2 จุด → dedup เหลือ 4) ตามลำดับที่ปรากฏ
        Assert.Equal(
            ["employee_name", "position", "salary", "start_date"],
            fields.Select(f => f.Key).ToList());

        // defaults: label = tag, type = text, required = false (FR-9), editor = default ของ type (FR-14)
        Assert.All(fields, f =>
        {
            Assert.Equal(f.Key, f.Label);
            Assert.Equal("text", f.Type);
            Assert.Equal("textbox", f.Editor);
            Assert.False(f.IsRequired);
        });

        // GET detail คืนนิยามชุดเดิม
        using var detail = await client.GetAsync($"api/templates/{templateId}");
        var detailBody = await detail.Content.ReadFromJsonAsync<TemplateDetailResult>(IntegrationTestFixture.Json);
        Assert.Equal(4, detailBody!.Fields.Count);
    }

    [Fact]
    public async Task Create_RejectsNonDocxFile()
    {
        using var client = fixture.CreateClient();
        using var form = new MultipartFormDataContent();
        form.Add(new StringContent("ไม่ใช่ template"), "name");
        var file = new ByteArrayContent("plain"u8.ToArray());
        file.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("text/plain");
        form.Add(file, "file", "template.txt");

        using var response = await client.PostAsync("api/templates", form);
        Assert.Equal(HttpStatusCode.BadRequest, response.StatusCode);
    }

    [Fact]
    public async Task Create_RejectsMissingName()
    {
        using var client = fixture.CreateClient();
        using var form = new MultipartFormDataContent();
        var file = new ByteArrayContent(TestDocx.BuildPlainDocx());
        file.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue(TestDocx.DocxContentType);
        form.Add(file, "file", "template.docx"); // ไม่ส่ง name

        using var response = await client.PostAsync("api/templates", form);
        Assert.Equal(HttpStatusCode.BadRequest, response.StatusCode);
    }

    [Fact]
    public async Task Update_SavesFieldDefinitions_AndMetadata()
    {
        using var client = fixture.CreateClient();
        var (templateId, fields) = await CreateDefaultTemplateAsync(client, $"แก้นิยาม {Guid.NewGuid():N}");

        var updated = new
        {
            description = "สัญญาจ้างฉบับมาตรฐาน",
            fields = fields.Select((f, i) => new
            {
                key = f.Key,
                label = $"ป้ายกำกับ {f.Key}",
                type = f.Key == "salary" ? "number" : f.Key == "start_date" ? "date" : "text",
                editor = f.Key == "employee_name" ? "textarea" : null as string, // ส่งเฉพาะ text field (FR-14)
                isRequired = f.Key == "employee_name",
                sortOrder = fields.Count - i, // กลับลำดับ
            }),
        };

        using var put = await client.PutAsJsonAsync($"api/templates/{templateId}", updated, IntegrationTestFixture.Json);
        Assert.Equal(HttpStatusCode.OK, put.StatusCode);
        var body = await put.Content.ReadFromJsonAsync<TemplateDetailResult>(IntegrationTestFixture.Json);

        Assert.Equal("สัญญาจ้างฉบับมาตรฐาน", body!.Description);
        Assert.Equal("ป้ายกำกับ employee_name", body.Fields[3].Label); // กลับลำดับแล้ว employee_name ท้ายสุด
        Assert.Equal("number", body.Fields.First(f => f.Key == "salary").Type);
        Assert.Equal("date", body.Fields.First(f => f.Key == "start_date").Type);
        Assert.True(body.Fields.First(f => f.Key == "employee_name").IsRequired);

        // editor: ที่ส่งคือ textarea, ที่ไม่ส่ง resolve เป็น default ของ type (FR-14)
        Assert.Equal("textarea", body.Fields.First(f => f.Key == "employee_name").Editor);
        Assert.Equal("textbox", body.Fields.First(f => f.Key == "position").Editor);
        Assert.Equal("number", body.Fields.First(f => f.Key == "salary").Editor);
        Assert.Equal("date", body.Fields.First(f => f.Key == "start_date").Editor);
    }

    [Fact]
    public async Task Update_RejectsUnknownFieldKey()
    {
        using var client = fixture.CreateClient();
        var (templateId, _) = await CreateDefaultTemplateAsync(client, $"key นอกไฟล์ {Guid.NewGuid():N}");

        using var put = await client.PutAsJsonAsync($"api/templates/{templateId}", new
        {
            fields = new[] { new { key = "not_in_file", label = "ไม่มีในไฟล์", type = "text", isRequired = false, sortOrder = 0 } },
        }, IntegrationTestFixture.Json);

        Assert.Equal(HttpStatusCode.BadRequest, put.StatusCode); // เพิ่ม/ลบ key ต้องผ่าน replace ไฟล์เท่านั้น
    }

    [Fact]
    public async Task Update_RejectsInvalidFieldType()
    {
        using var client = fixture.CreateClient();
        var (templateId, fields) = await CreateDefaultTemplateAsync(client, $"type ผิด {Guid.NewGuid():N}");

        using var put = await client.PutAsJsonAsync($"api/templates/{templateId}", new
        {
            fields = fields.Select(f => new { key = f.Key, label = f.Key, type = "datetime", isRequired = false, sortOrder = f.SortOrder }),
        }, IntegrationTestFixture.Json);

        Assert.Equal(HttpStatusCode.BadRequest, put.StatusCode);
    }

    [Fact]
    public async Task ReplaceFile_DetectsAddedAndRemovedTags()
    {
        using var client = fixture.CreateClient();
        var (templateId, _) = await CreateDefaultTemplateAsync(client, $"replace {Guid.NewGuid():N}");

        using var put = await client.PutAsync(
            $"api/templates/{templateId}/file",
            new MultipartFormDataContent
            {
                { new ByteArrayContent(TestDocx.BuildReplacementTemplateDocx())
                    { Headers = { ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue(TestDocx.DocxContentType) } },
                    "file", "replaced.docx" },
            });
        Assert.Equal(HttpStatusCode.OK, put.StatusCode);
        var body = await put.Content.ReadFromJsonAsync<ReplaceFileResult>(IntegrationTestFixture.Json);

        // เดิม: employee_name, position, salary, start_date → ใหม่: employee_name, note
        Assert.Equal(["note"], body!.AddedTags);
        Assert.Equal(
            new[] { "position", "salary", "start_date" }.Order(),
            body.RemovedTags.Order());
        Assert.Equal(["employee_name", "note"], body.Fields.Select(f => f.Key).ToList());
    }

    [Fact]
    public async Task Deactivate_HidesFromDefaultList_ButVisibleWithIncludeInactive()
    {
        using var client = fixture.CreateClient();
        var (templateId, _) = await CreateDefaultTemplateAsync(client, $"deactivate {Guid.NewGuid():N}");

        using var deactivate = await client.DeleteAsync($"api/templates/{templateId}");
        Assert.Equal(HttpStatusCode.NoContent, deactivate.StatusCode);

        using var activeList = await client.GetAsync("api/templates");
        var active = await activeList.Content.ReadFromJsonAsync<List<TemplateListItemResult>>(IntegrationTestFixture.Json);
        Assert.DoesNotContain(active!, t => t.Id == templateId);

        using var allList = await client.GetAsync("api/templates?includeInactive=true");
        var all = await allList.Content.ReadFromJsonAsync<List<TemplateListItemResult>>(IntegrationTestFixture.Json);
        Assert.Contains(all!, t => t.Id == templateId && !t.IsActive);
    }

    [Fact]
    public async Task Deactivate_ThenGenerate_Returns400_ButDocumentsOfTemplateStillAccessible()
    {
        using var client = fixture.CreateClient();
        var (templateId, _) = await CreateDefaultTemplateAsync(client, $"deactivate+generate {Guid.NewGuid():N}");

        // สร้างเอกสาร 1 ฉบับก่อน deactivate
        var values = new Dictionary<string, string>
        {
            ["employee_name"] = "สมชาย ใจดี",
            ["position"] = "โปรแกรมเมอร์",
            ["salary"] = "50000",
            ["start_date"] = "2026-08-20",
        };
        using var generate = await client.PostAsJsonAsync("api/documents/generate",
            new { templateId, values }, IntegrationTestFixture.Json);
        Assert.Equal(HttpStatusCode.Created, generate.StatusCode);
        var doc = await generate.Content.ReadFromJsonAsync<GenerateResult>(IntegrationTestFixture.Json);

        using var deactivate = await client.DeleteAsync($"api/templates/{templateId}");
        Assert.Equal(HttpStatusCode.NoContent, deactivate.StatusCode);

        // สร้างเอกสารใหม่ไม่ได้ (FR-9 policy)
        using var generateAgain = await client.PostAsJsonAsync("api/documents/generate",
            new { templateId, values }, IntegrationTestFixture.Json);
        Assert.Equal(HttpStatusCode.BadRequest, generateAgain.StatusCode);

        // แต่เอกสารเก่ายังเข้าถึงได้ครบ: list + detail + history + download (FR-9 + FR-12)
        using var list = await client.GetAsync($"api/templates/{templateId}/documents");
        Assert.Equal(HttpStatusCode.OK, list.StatusCode);
        var documents = await list.Content.ReadFromJsonAsync<List<TemplateDocItem>>(IntegrationTestFixture.Json);
        var listItem = documents!.Single();
        Assert.Equal(doc!.DocumentId, listItem.DocumentId);
        Assert.Equal(1, listItem.VersionCount);

        using var detail = await client.GetAsync($"api/documents/{doc!.DocumentId}");
        Assert.Equal(HttpStatusCode.OK, detail.StatusCode);
        Assert.True((await detail.Content.ReadFromJsonAsync<DocDetail>(IntegrationTestFixture.Json))!.TemplateIsActive is false);

        using var history = await client.GetAsync($"api/documents/{doc.DocumentId}/versions");
        Assert.Equal(HttpStatusCode.OK, history.StatusCode);

        using var download = await client.GetAsync($"api/documents/{doc.DocumentId}/versions/{doc.VersionId}/download");
        Assert.Equal(HttpStatusCode.OK, download.StatusCode);
    }

    [Fact]
    public async Task Get_UnknownTemplate_Returns404()
    {
        using var client = fixture.CreateClient();
        using var response = await client.GetAsync($"api/templates/{Guid.NewGuid()}");
        Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
    }

    [Fact]
    public async Task ListDocuments_UnknownTemplate_Returns404()
    {
        using var client = fixture.CreateClient();
        using var response = await client.GetAsync($"api/templates/{Guid.NewGuid()}/documents");
        Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
    }
}