package app

import (
	"strings"
	"testing"

	"glint/internal/grammar"
	"glint/internal/theme"
)

// TestApplyGrammarDiagsRendersUnderline checks the app buckets a diagnostic batch
// by line and the editor renders it as a green undercurl. FlexokiDark's Grammar
// green is #879A39 -> the underline-color SGR carries its RGB (135,154,57).
func TestApplyGrammarDiagsRendersUnderline(t *testing.T) {
	a := newApp()
	a.setSize(100, 24)
	a.editor.SetTheme(theme.FlexokiDark())
	a.editor.SetContent([]byte("This is a a test"))
	a.editor.SetGrammar(true)

	a.applyGrammarDiags([]grammar.Diag{{Line: 0, StartCol: 8, EndCol: 11, Message: "repeat"}})

	const greenSGR = "58:2::135:154:57" // undercurl color for #879A39
	if !strings.Contains(a.editor.View(), greenSGR) {
		t.Error("expected a green grammar undercurl (SGR " + greenSGR + ") in the rendered view")
	}
}

// TestGrammarEndToEnd drives the whole pipeline against the real harper: Init
// starts the subprocess and opens the buffer, the listener command blocks for the
// first diagnostic batch, and applying it renders a green undercurl. Skipped
// without harper on PATH or under -short.
func TestGrammarEndToEnd(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping live harper test under -short")
	}
	if !grammar.Available() {
		t.Skip("harper-ls not on PATH")
	}
	a := newApp()
	a.setSize(100, 24)
	a.editor.SetTheme(theme.FlexokiDark())
	a.editor.SetContent([]byte("This is a a test.\n"))

	listen := a.Init() // starts harper, opens the buffer, returns the listener cmd
	defer a.Close()
	if a.grammar == nil {
		t.Fatal("Init did not start a harper client")
	}
	msg := listen() // blocks until harper publishes diagnostics
	diag, ok := msg.(grammarDiagMsg)
	if !ok {
		t.Fatalf("listener returned %T, want grammarDiagMsg", msg)
	}
	a.applyGrammarDiags(diag.diags)

	const greenSGR = "58:2::135:154:57" // #879A39 undercurl
	if !strings.Contains(a.editor.View(), greenSGR) {
		t.Error("no green grammar undercurl after live harper round-trip")
	}
}

// TestGrammarNilClientNoOps confirms the debounce/flush path is inert without a
// running harper client, so plain app tests never touch a subprocess.
func TestGrammarNilClientNoOps(t *testing.T) {
	a := newApp()
	if a.grammar != nil {
		t.Fatal("newApp should not start a harper client")
	}
	if cmd := a.grammarChanged(); cmd != nil {
		t.Error("grammarChanged should return nil without a client")
	}
	a.grammarFlush(a.grammarGen) // must not panic
	a.grammarOpen()              // must not panic
}