package web_test

import (
	"context"
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"net/url"
	"strings"
	"testing"
	"time"
)

// TestBulkPageHasNoNestedForms guards against the chip-add <form> being
// nested inside the bulk-actions <form>. HTML forbids nested forms and
// browsers silently flatten them — the chip-add's hx-trigger="submit"
// stops firing and the chip-add inputs leak into the outer Apply form.
// Phase 3n regression.
func TestBulkPageHasNoNestedForms(t *testing.T) {
	srv, pool := mustServer(t)
	defer pool.Close()
	h := srv.Routes()
	_, body := get(t, h, "/admin/bulk")

	// Locate bulk-actions form and verify NO inner <form> opens before its
	// matching </form>. A naive but robust check: between the opening
	// <form id="bulk-actions" ...> and the next </form>, there must be no
	// other <form opening.
	startTag := `<form id="bulk-actions"`
	open := strings.Index(body, startTag)
	if open < 0 {
		t.Fatalf("bulk page lacks <form id=\"bulk-actions\">; body sample:\n%s", body[:min3(800, len(body))])
	}
	tail := body[open:]
	end := strings.Index(tail, "</form>")
	if end < 0 {
		t.Fatalf("bulk-actions form never closes")
	}
	inner := tail[len(startTag):end]
	if strings.Contains(inner, "<form") {
		t.Errorf("bulk-actions form contains a nested <form ...>: HTML forbids this and browsers flatten it. Slice:\n%s",
			inner[:min3(1200, len(inner))])
	}
}

// TestBulkApplyEmptyActionRendersInlineBanner: clicking Apply without
// filling an action field should not 400 + plain-text error page (which
// HTMX swaps as the whole #bulk-section). It should render the section
// with an inline banner. Phase 3n regression.
func TestBulkApplyEmptyActionRendersInlineBanner(t *testing.T) {
	srv, pool := mustServer(t)
	defer pool.Close()
	h := srv.Routes()
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	// Seed one item we can tick a checkbox for.
	stamp := strings.ReplaceAll(time.Now().UTC().Format("150405.000000"), ".", "")
	slug := "bulk-empty-act-" + stamp
	var dev, id string
	if err := pool.QueryRow(ctx, `select id from projax.items where slug='dev' and cardinality(parent_ids)=0`).Scan(&dev); err != nil {
		t.Fatalf("dev: %v", err)
	}
	if err := pool.QueryRow(ctx,
		`insert into projax.items (kind, title, slug, parent_ids)
		  values (array['project']::text[], 'bulk-empty', $1, ARRAY[$2]::uuid[])
		  returning id`,
		slug, dev,
	).Scan(&id); err != nil {
		t.Fatalf("seed: %v", err)
	}
	defer pool.Exec(context.Background(), `delete from projax.items where id=$1`, id)

	form := url.Values{}
	form.Set("ids", id)
	// Intentionally NO add_tag / remove_tag / set_mgmt / set_status set.
	req := httptest.NewRequest(http.MethodPost, "/admin/bulk/apply", strings.NewReader(form.Encode()))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	req.Header.Set("HX-Request", "true")
	w := httptest.NewRecorder()
	h.ServeHTTP(w, req)

	code := w.Result().StatusCode
	body := readBodyString(t, w.Result().Body)
	if code != 200 {
		t.Fatalf("expected 200 with inline banner for empty Apply, got %d body=%s", code, body)
	}
	if !strings.Contains(body, `id="bulk-section"`) {
		t.Errorf("response should re-render the bulk section, not replace it with an error message")
	}
	if !strings.Contains(strings.ToLower(body), "action") {
		t.Errorf("response should contain a 'no action chosen' style banner; body:\n%s", body[:min3(600, len(body))])
	}
}

// TestBulkApplyEmptyIdsRendersInlineBanner: clicking Apply with no rows
// ticked should also render the section with a banner, not 400.
func TestBulkApplyEmptyIdsRendersInlineBanner(t *testing.T) {
	srv, pool := mustServer(t)
	defer pool.Close()
	h := srv.Routes()
	form := url.Values{}
	form.Set("add_tag", "x") // action chosen but no ids
	req := httptest.NewRequest(http.MethodPost, "/admin/bulk/apply", strings.NewReader(form.Encode()))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	req.Header.Set("HX-Request", "true")
	w := httptest.NewRecorder()
	h.ServeHTTP(w, req)

	code := w.Result().StatusCode
	body := readBodyString(t, w.Result().Body)
	if code != 200 {
		t.Fatalf("expected 200 with inline banner for empty ids, got %d body=%s", code, body)
	}
	if !strings.Contains(body, `id="bulk-section"`) {
		t.Errorf("response should re-render the bulk section, not replace it with an error message")
	}
}

// TestBulkApplyRendersWithFilterPreserved: after Apply, the re-rendered
// section should keep multi-value filter selections (tag=A AND tag=B, the
// browser sends two name=tag entries). Pre-fix renderBulkList used
// r.FormValue which only returns the FIRST value, dropping B.
func TestBulkApplyRendersWithFilterPreserved(t *testing.T) {
	srv, pool := mustServer(t)
	defer pool.Close()
	h := srv.Routes()
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	// Seed two items in different areas, distinct tags so we can verify the
	// filter narrows.
	stamp := strings.ReplaceAll(time.Now().UTC().Format("150405.000000"), ".", "")
	var dev, home string
	if err := pool.QueryRow(ctx, `select id from projax.items where slug='dev' and cardinality(parent_ids)=0`).Scan(&dev); err != nil {
		t.Fatalf("dev: %v", err)
	}
	if err := pool.QueryRow(ctx, `select id from projax.items where slug='home' and cardinality(parent_ids)=0`).Scan(&home); err != nil {
		t.Fatalf("home: %v", err)
	}
	mk := func(parent, slug string, tags []string) string {
		var id string
		if err := pool.QueryRow(ctx,
			`insert into projax.items (kind, title, slug, parent_ids, tags)
			  values (array['project']::text[], $1, $2, ARRAY[$3]::uuid[], $4)
			  returning id`,
			"f", slug, parent, tags,
		).Scan(&id); err != nil {
			t.Fatalf("seed %s: %v", slug, err)
		}
		return id
	}
	tagA := "bulkfilt-a-" + stamp
	tagB := "bulkfilt-b-" + stamp
	devSlug := "bulkfilt-dev-" + stamp
	homeSlug := "bulkfilt-home-" + stamp
	devID := mk(dev, devSlug, []string{tagA, tagB})
	homeID := mk(home, homeSlug, []string{tagA})
	defer func() {
		_, _ = pool.Exec(context.Background(), `delete from projax.items where id in ($1, $2)`, devID, homeID)
	}()

	// Apply: ids=devID, add_tag=newtag, and tag filter has BOTH tagA AND tagB
	// (multi-select scenario).
	form := url.Values{}
	form.Add("ids", devID)
	form.Set("add_tag", "newtag-"+stamp)
	form.Add("tag", tagA)
	form.Add("tag", tagB)
	req := httptest.NewRequest(http.MethodPost, "/admin/bulk/apply", strings.NewReader(form.Encode()))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	req.Header.Set("HX-Request", "true")
	w := httptest.NewRecorder()
	h.ServeHTTP(w, req)

	if w.Result().StatusCode != 200 {
		body := readBodyString(t, w.Result().Body)
		t.Fatalf("apply → %d body=%s", w.Result().StatusCode, body)
	}
	body := readBodyString(t, w.Result().Body)
	// dev-item carries both tags → matches the AND filter → should appear in the rendered list.
	if !strings.Contains(body, fmt.Sprintf("/i/dev.%s", devSlug)) {
		t.Errorf("expected dev-row to remain visible after Apply (filter AND-matches both tags)")
	}
	// home-item carries only tagA → should NOT appear (filter requires BOTH).
	if strings.Contains(body, fmt.Sprintf("/i/home.%s", homeSlug)) {
		t.Errorf("home-row should be filtered out — has only tagA, filter required tagA+tagB")
	}
}

// readBodyString reads an HTTP response body as a string. Helper used by
// the regression tests since httptest.NewRecorder().Result().Body is a
// ReadCloser.
func readBodyString(t *testing.T, r io.ReadCloser) string {
	t.Helper()
	defer r.Close()
	b, _ := io.ReadAll(r)
	return string(b)
}

func min3(a, b int) int {
	if a < b {
		return a
	}
	return b
}