// SPDX-License-Identifier: GPL-3.0-or-later

package model

import (
	"strings"
	"testing"

	"krino/internal/config"
)

// formsFile is a directory file with comments in the places that matter:
// above a rule (its own), inside a rule, and free-standing.
const formsFile = `(path "~/dl")

(exclude (name "^keep-"))

;; invoices go to their year
(rule "invoices"
  (when (and (type pdf) (content "invoice")))
  (move "Invoices/{mtime:%Y}")
  (stop))

(rule "images"
  (when (type image))   ; anything the type table calls an image
  (move "Images")
  (stop))

;; last resort

(rule "rest"
  (move "Other"))
`

// openForms puts text in an editor over the sandbox's file.
func openForms(t *testing.T, text string) *Rules {
	t.Helper()
	e, _ := sandboxDir(t, formsFile, map[string]string{"a.pdf": "one"})
	r, err := OpenRules(e, "dl")
	if err != nil {
		t.Fatal(err)
	}
	if text != "" {
		r.SetText(text)
	}
	return r
}

// TestFormsLists: every editable form of the file, in file order, named the
// way the list shows it.
func TestFormsLists(t *testing.T) {
	r := openForms(t, "")
	forms, err := r.Forms()
	if err != nil {
		t.Fatal(err)
	}
	var got []string
	for _, f := range forms {
		got = append(got, f.Label)
	}
	want := []string{`(exclude (name "^keep-"))`, "invoices", "images", "rest"}
	if strings.Join(got, "|") != strings.Join(want, "|") {
		t.Errorf("forms = %v, want %v", got, want)
	}
	if forms[0].Kind != ExcludeForm || forms[1].Kind != RuleForm {
		t.Errorf("kinds = %v, %v", forms[0].Kind, forms[1].Kind)
	}
	if forms[1].Rule == nil || forms[1].Rule.Name != "invoices" {
		t.Errorf("rule form carries no rule: %+v", forms[1])
	}
}

// TestDeleteFormTakesItsComments: a rule's block is its form plus the
// comment lines directly above it with no blank line between (GUI design
// §5.1), so deleting it does not leave its comment stranded - while a
// comment separated by a blank line stays.
func TestDeleteFormTakesItsComments(t *testing.T) {
	r := openForms(t, "")
	if err := r.DeleteForm(1); err != nil { // invoices, with its comment
		t.Fatal(err)
	}
	if strings.Contains(r.Text, "invoices go to their year") {
		t.Errorf("the rule's own comment was left behind:\n%s", r.Text)
	}
	if strings.Contains(r.Text, `(rule "invoices"`) {
		t.Errorf("the rule is still there:\n%s", r.Text)
	}
	// The free-standing comment above "rest" is separated by a blank line,
	// so deleting that rule leaves it alone.
	forms, err := r.Forms()
	if err != nil {
		t.Fatal(err)
	}
	if err := r.DeleteForm(len(forms) - 1); err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(r.Text, ";; last resort") {
		t.Errorf("a comment separated by a blank line was taken too:\n%s", r.Text)
	}
	if diags := r.Check(); len(diags) > 0 {
		t.Errorf("the file no longer loads: %v", diags)
	}
}

// TestMoveForm: a rule moves with its comments, and the order of everything
// else is kept.
func TestMoveForm(t *testing.T) {
	r := openForms(t, "")
	if err := r.MoveForm(2, -1); err != nil { // images, up past invoices
		t.Fatal(err)
	}
	forms, err := r.Forms()
	if err != nil {
		t.Fatal(err)
	}
	var got []string
	for _, f := range forms {
		got = append(got, f.Label)
	}
	want := []string{`(exclude (name "^keep-"))`, "images", "invoices", "rest"}
	if strings.Join(got, "|") != strings.Join(want, "|") {
		t.Fatalf("after moving up: %v, want %v", got, want)
	}
	// The comment travelled with its rule, and still sits above it.
	iInvoices := strings.Index(r.Text, `(rule "invoices"`)
	iComment := strings.Index(r.Text, ";; invoices go to their year")
	if iComment < 0 || iComment > iInvoices {
		t.Errorf("the comment did not travel with its rule:\n%s", r.Text)
	}
	if strings.Index(r.Text, `(rule "images"`) > iComment {
		t.Errorf("images did not move above invoices:\n%s", r.Text)
	}
	if diags := r.Check(); len(diags) > 0 {
		t.Errorf("the file no longer loads: %v", diags)
	}
	// Moving the first form up, or the last down, does nothing.
	before := r.Text
	if err := r.MoveForm(0, -1); err != nil {
		t.Fatal(err)
	}
	if err := r.MoveForm(len(forms)-1, 1); err != nil {
		t.Fatal(err)
	}
	if r.Text != before {
		t.Error("moving past the ends changed the file")
	}
}

// TestAddRuleAfter: a new rule lands after the one selected, is the form
// the printer writes, and the file still loads.
func TestAddRuleAfter(t *testing.T) {
	r := openForms(t, "")
	i, err := r.AddRuleAfter(1, "new one")
	if err != nil {
		t.Fatal(err)
	}
	forms, err := r.Forms()
	if err != nil {
		t.Fatal(err)
	}
	if i != 2 || forms[2].Label != "new one" {
		t.Fatalf("new rule at %d: %v", i, labels(forms))
	}
	if diags := r.Check(); len(diags) > 0 {
		t.Errorf("the file no longer loads: %v", diags)
	}
}

// TestReplaceForm: editing one form rewrites that form's text and nothing
// else - every comment and every other line stays byte for byte.
func TestReplaceForm(t *testing.T) {
	r := openForms(t, "")
	forms, err := r.Forms()
	if err != nil {
		t.Fatal(err)
	}
	rule := *forms[1].Rule // invoices
	rule.Actions = []config.Action{{Kind: config.Move, Arg: "Faktury"}}
	if err := r.ReplaceForm(1, config.PrintRule(&rule)); err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(r.Text, `(move "Faktury")`) {
		t.Errorf("the edit did not land:\n%s", r.Text)
	}
	if strings.Contains(r.Text, `(move "Invoices/{mtime:%Y}")`) {
		t.Errorf("the old action is still there:\n%s", r.Text)
	}
	for _, keep := range []string{";; invoices go to their year", ";; last resort",
		"; anything the type table calls an image", `(exclude (name "^keep-"))`} {
		if !strings.Contains(r.Text, keep) {
			t.Errorf("replacing one form lost %q:\n%s", keep, r.Text)
		}
	}
	if diags := r.Check(); len(diags) > 0 {
		t.Errorf("the file no longer loads: %v", diags)
	}
}

// TestFormHasComments: a form with a comment inside it cannot be rewritten
// from a form editor without losing it, so the caller is warned; a
// semicolon inside a string is not a comment (GUI design §5.1).
func TestFormHasComments(t *testing.T) {
	r := openForms(t, "")
	forms, err := r.Forms()
	if err != nil {
		t.Fatal(err)
	}
	if got, err := r.FormHasComments(2); err != nil || !got { // images
		t.Errorf("FormHasComments(images) = %v, %v; want true", got, err)
	}
	if got, err := r.FormHasComments(1); err != nil || got { // invoices
		t.Errorf("FormHasComments(invoices) = %v, %v; want false", got, err)
	}
	_ = forms

	r.SetText("(path \"~/dl\")\n(rule \"semi\" (when (name \"a;b\")) (move \"Out\"))\n")
	if got, err := r.FormHasComments(0); err != nil || got {
		t.Errorf("a semicolon inside a string counted as a comment: %v, %v", got, err)
	}
}

// TestFormsRefusesBrokenText: the forms list comes from parsing, so text
// that does not parse has no forms to show, and says so.
func TestFormsRefusesBrokenText(t *testing.T) {
	r := openForms(t, "(path \"~/dl\")\n(rule \"unclosed\"\n")
	if _, err := r.Forms(); err == nil {
		t.Error("Forms answered for text that does not parse")
	}
	if err := r.DeleteForm(0); err == nil {
		t.Error("DeleteForm acted on text that does not parse")
	}
}

func labels(forms []Form) []string {
	var out []string
	for _, f := range forms {
		out = append(out, f.Label)
	}
	return out
}