package effects

import (
	"context"
	"log/slog"
	"strings"
	"testing"

	coretypes "github.com/enmanuel/agents/pkg/llm"
)

// TestIntegration_StreamToProgressReporter simulates the full flow:
// parseStreamLine produces events → ProgressReporter consumes them → mock sender records calls.
// This validates the complete pipeline from raw JSON lines to Matrix messages.
func TestIntegration_StreamToProgressReporter(t *testing.T) {
	sender := &mockProgressSender{}
	pr := NewProgressReporter(sender, "!room:integration", slog.Default())
	pr.minInterval = 0 // disable rate limiting for test

	fn := pr.StreamFunc()

	// Simulate a realistic stream-json session:
	// 1. Init event
	fn(coretypes.StreamEvent{Kind: coretypes.StreamInit})

	// 2. Tool use: Bash
	fn(coretypes.StreamEvent{
		Kind:      coretypes.StreamToolUse,
		ToolName:  "Bash",
		ToolInput: "git status",
	})

	// 3. Tool use: Read
	fn(coretypes.StreamEvent{
		Kind:      coretypes.StreamToolUse,
		ToolName:  "Read",
		ToolInput: "/home/user/project/main.go",
	})

	// 4. Tool use: Edit
	fn(coretypes.StreamEvent{
		Kind:      coretypes.StreamToolUse,
		ToolName:  "Edit",
		ToolInput: "/home/user/project/main.go",
	})

	// 5. Text event (intermediate, should be ignored)
	fn(coretypes.StreamEvent{
		Kind:    coretypes.StreamText,
		Content: "I've made the changes...",
	})

	// 6. Result event (should be ignored by progress reporter)
	fn(coretypes.StreamEvent{
		Kind:    coretypes.StreamResult,
		Content: "Here is the final answer with all changes applied.",
	})

	// Verify sends: only 1 initial send
	if len(sender.sends) != 1 {
		t.Errorf("expected 1 send (init), got %d", len(sender.sends))
	}
	if !strings.Contains(sender.sends[0], "Procesando") {
		t.Errorf("init message should contain 'Procesando', got %q", sender.sends[0])
	}

	// Verify edits: 3 tool use events
	if len(sender.edits) != 3 {
		t.Fatalf("expected 3 edits (tool uses), got %d", len(sender.edits))
	}

	// First edit: Bash
	if !strings.Contains(sender.edits[0], "Bash") {
		t.Errorf("edit[0] should mention Bash, got %q", sender.edits[0])
	}
	if !strings.Contains(sender.edits[0], "git status") {
		t.Errorf("edit[0] should show input, got %q", sender.edits[0])
	}

	// Second edit: Read
	if !strings.Contains(sender.edits[1], "Read") {
		t.Errorf("edit[1] should mention Read, got %q", sender.edits[1])
	}

	// Third edit: Edit
	if !strings.Contains(sender.edits[2], "Edit") {
		t.Errorf("edit[2] should mention Edit, got %q", sender.edits[2])
	}

	// All edits should target the same event ID
	for i, target := range sender.editTargets {
		if target != "$progress_msg_1" {
			t.Errorf("editTarget[%d] = %q, want %q", i, target, "$progress_msg_1")
		}
	}

	// Finalize
	pr.Finalize("\u2705 *Completado*")

	if len(sender.edits) != 4 {
		t.Fatalf("expected 4 edits (3 tools + 1 finalize), got %d", len(sender.edits))
	}
	if !strings.Contains(sender.edits[3], "Completado") {
		t.Errorf("finalize edit should contain 'Completado', got %q", sender.edits[3])
	}
}

// TestIntegration_NoStreamingNoSideEffects verifies that when streaming is
// not enabled, no ProgressReporter is created and no Matrix side effects occur.
// This is a regression test for the streaming=false default behavior.
func TestIntegration_NoStreamingNoSideEffects(t *testing.T) {
	sender := &mockProgressSender{}

	// Simulate the handler check: streaming disabled → progress is nil
	var progress *ProgressReporter // nil, because streaming is disabled

	if progress != nil {
		t.Error("progress reporter should be nil when streaming is disabled")
	}

	// Verify no sends or edits happened
	if len(sender.sends) != 0 {
		t.Errorf("expected 0 sends, got %d", len(sender.sends))
	}
	if len(sender.edits) != 0 {
		t.Errorf("expected 0 edits, got %d", len(sender.edits))
	}
}

// TestIntegration_ProgressReporterWithSendError verifies that the reporter
// handles send errors gracefully without panicking.
func TestIntegration_ProgressReporterWithSendError(t *testing.T) {
	sender := &errorSender{}
	pr := NewProgressReporter(sender, "!room:test", slog.Default())
	pr.minInterval = 0

	fn := pr.StreamFunc()

	// Should not panic even when send fails
	fn(coretypes.StreamEvent{Kind: coretypes.StreamInit})

	// EventID should be empty since send failed
	if pr.EventID() != "" {
		t.Errorf("expected empty EventID after send error, got %q", pr.EventID())
	}

	// Finalize should be a no-op since no message was sent
	pr.Finalize("Done")
}

// errorSender always returns errors.
type errorSender struct {
	fakeMatrixSender
}

func (e *errorSender) SendMarkdownGetID(_ context.Context, _, _ string) (string, error) {
	return "", context.DeadlineExceeded
}

func (e *errorSender) EditMessage(_ context.Context, _, _, _ string) error {
	return context.DeadlineExceeded
}