package geminiweb

import (
	"context"
	"fmt"
	"strings"
	"time"

	"github.com/go-rod/rod"
	"github.com/go-rod/rod/lib/proto"
)

const geminiURL = "https://gemini.google.com/app"

var modelSelectors = map[string]string{
	"gemini-2.0-flash":        "Flash",
	"gemini-2.5-pro":          "Pro",
	"gemini-2.5-pro-thinking": "Thinking",
}

func NormalizeModel(model string) string {
	if strings.HasPrefix(model, "gemini-") {
		return model
	}
	return "gemini-" + model
}

func GetModelDisplayName(model string) string {
	if name, ok := modelSelectors[model]; ok {
		return name
	}
	return "Flash"
}

func NavigateToGemini(page *rod.Page) error {
	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
	defer cancel()

	if err := page.Context(ctx).Navigate(geminiURL); err != nil {
		return fmt.Errorf("failed to navigate to gemini: %w", err)
	}
	return page.Context(ctx).WaitLoad()
}

func IsLoggedIn(page *rod.Page) bool {
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	// 嘗試多種可能的登入狀態指示器
	selectors := []string{
		`textarea`,
		`[contenteditable="true"]`,
		`[aria-label*="chat" i]`,
		`button[aria-label*="new" i]`,
	}

	for _, sel := range selectors {
		_, err := page.Context(ctx).Element(sel)
		if err == nil {
			return true
		}
	}
	return false
}

func SelectModel(page *rod.Page, model string) error {
	displayName := GetModelDisplayName(model)

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	// 嘗試多種可能的模型選擇器選擇器
	selectors := []string{
		`button[aria-label*="model" i]`,
		`button[aria-label*="Model" i]`,
		`[data-test-id="model-selector"]`,
		`button[aria-haspopup="listbox"]`,
		`[class*="model-selector"]`,
		`[class*="model"] button`,
	}

	var modelSwitcher *rod.Element
	var err error
	for _, sel := range selectors {
		modelSwitcher, err = page.Context(ctx).Element(sel)
		if err == nil {
			break
		}
	}

	if err != nil {
		// 如果找不到模型選擇器，可能是頁面已經在正確的模型上，或是 Gemini 的 UI 不同
		fmt.Printf("Warning: model selector not found, using current model (requested: %s)\n", displayName)
		return nil
	}

	// 獲取目前的模型文字
	currentText, _ := modelSwitcher.Text()
	if currentText != "" && strings.Contains(strings.ToLower(currentText), strings.ToLower(displayName)) {
		// 已經在正確的模型上
		return nil
	}

	if err := modelSwitcher.Click(proto.InputMouseButtonLeft, 1); err != nil {
		return fmt.Errorf("failed to click model selector: %w", err)
	}

	time.Sleep(500 * time.Millisecond)

	// 嘗試多種可能的選項選擇器
	optionSelectors := []string{
		fmt.Sprintf(`[aria-label*="%s" i]`, displayName),
		fmt.Sprintf(`[data-value*="%s" i]`, displayName),
		fmt.Sprintf(`text=%s`, displayName),
		`[role="option"]`,
	}

	var option *rod.Element
	for _, sel := range optionSelectors {
		option, err = page.Context(ctx).Element(sel)
		if err == nil {
			break
		}
	}

	if err != nil {
		fmt.Printf("Warning: model option %s not found, using current model\n", displayName)
		return nil
	}

	return option.Click(proto.InputMouseButtonLeft, 1)
}

func SendPrompt(page *rod.Page, prompt string) error {
	fmt.Printf("[GeminiWeb] Finding input field...\n")

	// 嘗試多種可能的輸入框選擇器
	selectors := []string{
		`textarea`,
		`[contenteditable="true"]`,
		`[role="textbox"]`,
		`div[contenteditable="true"]`,
		`div[role="textbox"]`,
		`.ql-editor`,
		`rich-textarea`,
	}

	var textarea *rod.Element
	var err error
	for _, sel := range selectors {
		fmt.Printf("  Trying selector: %s\n", sel)
		textarea, err = page.Element(sel)
		if err == nil {
			fmt.Printf("  Found with: %s\n", sel)
			break
		}
	}

	if err != nil {
		return fmt.Errorf("input field not found after trying all selectors: %w", err)
	}

	fmt.Printf("[GeminiWeb] Typing prompt (%d chars)...\n", len(prompt))
	if err := textarea.Input(prompt); err != nil {
		return fmt.Errorf("failed to input prompt: %w", err)
	}

	fmt.Printf("[GeminiWeb] Finding send button...\n")
	time.Sleep(500 * time.Millisecond)

	// 嘗試多種可能的發送按鈕選擇器
	btnSelectors := []string{
		`button[type="submit"]`,
		`button[aria-label*="Send" i]`,
		`button[aria-label*="submit" i]`,
		`button:has(svg)`,
		`button`,
	}

	var sendBtn *rod.Element
	for _, sel := range btnSelectors {
		fmt.Printf("  Trying button selector: %s\n", sel)
		sendBtn, err = page.Element(sel)
		if err == nil {
			// 檢查是否是發送按鈕（不是其他按鈕）
			ariaLabel, _ := sendBtn.Attribute("aria-label")
			text, _ := sendBtn.Text()
			if ariaLabel != nil || text != "" {
				fmt.Printf("  Found button with aria-label=%v text=%s\n", ariaLabel, truncate(text, 20))
			}
		}
		if err == nil {
			fmt.Printf("  Found send button with: %s\n", sel)
			break
		}
	}

	if err != nil {
		// 嘗試按 Enter 鍵發送
		fmt.Printf("[GeminiWeb] No send button found, trying Enter key...\n")
		if err := page.Keyboard.Press('\n'); err != nil {
			return fmt.Errorf("failed to press Enter: %w", err)
		}
		return nil
	}

	fmt.Printf("[GeminiWeb] Clicking send button...\n")
	return sendBtn.Click(proto.InputMouseButtonLeft, 1)
}

func truncate(s string, max int) string {
	if len(s) <= max {
		return s
	}
	return s[:max] + "..."
}

func WaitForResponse(page *rod.Page, onChunk func(text string), onThinking func(thinking string), onComplete func()) error {
	lastText := ""
	lastThinking := ""
	responseComplete := false

	timeout := time.NewTimer(120 * time.Second)
	defer timeout.Stop()

	ticker := time.NewTicker(500 * time.Millisecond)
	defer ticker.Stop()

	for {
		select {
		case <-timeout.C:
			return fmt.Errorf("response timeout")
		case <-ticker.C:
			textChanged := false

			responseEls, err := page.Elements(`.response-text, message-content, .model-response, div[data-test-id="response"]`)
			if err == nil && len(responseEls) > 0 {
				for _, el := range responseEls {
					text, _ := el.Text()
					text = strings.TrimSpace(text)
					if text != "" && text != lastText {
						if strings.Contains(text, lastText) {
							newPart := strings.TrimPrefix(text, lastText)
							if newPart != "" {
								onChunk(newPart)
							}
						} else {
							onChunk(text)
						}
						lastText = text
						textChanged = true
					}
				}
			}

			thinkingEls, err := page.Elements(`.thinking-content, .thought-text, div[data-test-id="thinking"]`)
			if err == nil && len(thinkingEls) > 0 {
				for _, el := range thinkingEls {
					thinking, _ := el.Text()
					thinking = strings.TrimSpace(thinking)
					if thinking != "" && thinking != lastThinking {
						if strings.Contains(thinking, lastThinking) {
							newPart := strings.TrimPrefix(thinking, lastThinking)
							if newPart != "" {
								onThinking(newPart)
							}
						} else {
							onThinking(thinking)
						}
						lastThinking = thinking
						textChanged = true
					}
				}
			}

			doneBtn, err := page.Element(`button[aria-label*="stop"], button[aria-label*="regenerate"]`)
			if err == nil && doneBtn != nil {
				ariaLabel, _ := doneBtn.Attribute("aria-label")
				if ariaLabel != nil && (*ariaLabel == "Stop" || strings.Contains(*ariaLabel, "regenerate")) {
					if !responseComplete && lastText != "" {
						responseComplete = true
						onComplete()
						return nil
					}
				}
			}

			if !textChanged && responseComplete {
				return nil
			}
		}
	}
}

func IsRateLimited(page *rod.Page) bool {
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	defer cancel()

	el, err := page.Context(ctx).Element(`[class*="rate-limit"], [class*="quota"], [data-test-id="rate-limited"]`)
	return err == nil && el != nil
}

func GetRateLimitMessage(page *rod.Page) string {
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	defer cancel()

	el, err := page.Context(ctx).Element(`[class*="rate-limit"], [class*="quota"], [class*="error-message"]`)
	if err != nil || el == nil {
		return ""
	}

	text, _ := el.Text()
	return strings.TrimSpace(text)
}