//go:build llm_script

package main

import (
	"context"
	"database/sql"
	"flag"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"os"
	"os/exec"
	"regexp"
	"strings"
	"time"
)

const (
	defaultSensenovaDocsURL   = "https://platform.sensenova.cn/docs"
	defaultSensenovaModelsURL = "https://www.sensenova.cn/models"
)

type sensenovaPricingImportConfig struct {
	DocsURL   string
	ModelsURL string
	Fixture   string
	DryRun    bool
	Timeout   time.Duration
}

type sensenovaPricingFixture struct {
	DocsHTML   string
	ModelsText string
}

type sensenovaPricingDocModel struct {
	ModelName     string
	ModelID       string
	QuotaPer5Hour int
}

var (
	sensenovaFixtureSplitMarker  = "\n===SENSENOVA_MODELS_BUNDLE===\n"
	sensenovaOverviewCardPattern = regexp.MustCompile(`(?s)<h4[^>]*>([^<]+)</h4>.*?调用次数限制</p><p[^>]*>每5小时([0-9]+)次</p>.*?MODEL ID</p><code[^>]*>([^<]+)</code>`)
	sensenovaModelsScriptPattern = regexp.MustCompile(`src="([^"]+/_next/static/chunks/[^"]+\.js|/_next/static/chunks/[^"]+\.js)"`)
	sensenovaPricingZeroPattern  = regexp.MustCompile(`(?s)"pricing"\s*:\s*\{\s*"prompt"\s*:\s*"0"\s*,\s*"completion"\s*:\s*"0"\s*,\s*"image"\s*:\s*"0"\s*,\s*"request"\s*:\s*"0"`)
)

func main() {
	loadSubscriptionImportEnv()

	var docsURL string
	var modelsURL string
	var fixture string
	var dryRun bool
	var timeoutSeconds int

	flag.StringVar(&docsURL, "docs-url", defaultSensenovaDocsURL, "商汤 SenseNova API 文档页")
	flag.StringVar(&modelsURL, "models-url", defaultSensenovaModelsURL, "商汤 SenseNova 模型页")
	flag.StringVar(&fixture, "fixture", "", "商汤 SenseNova 价格样例文件")
	flag.BoolVar(&dryRun, "dry-run", false, "仅解析并打印摘要，不写入数据库")
	flag.IntVar(&timeoutSeconds, "timeout", 45, "请求超时（秒）")
	flag.Parse()

	cfg := sensenovaPricingImportConfig{
		DocsURL:   docsURL,
		ModelsURL: modelsURL,
		Fixture:   fixture,
		DryRun:    dryRun,
		Timeout:   time.Duration(timeoutSeconds) * time.Second,
	}

	var db *sql.DB
	var err error
	if !cfg.DryRun {
		db, err = subscriptionImportDB()
		if err != nil {
			fmt.Fprintf(os.Stderr, "open db: %v\n", err)
			os.Exit(1)
		}
		defer db.Close()
	}

	if err := runSensenovaPricingImport(cfg, db, os.Stdout); err != nil {
		fmt.Fprintf(os.Stderr, "import_sensenova_pricing: %v\n", err)
		os.Exit(1)
	}
}

func runSensenovaPricingImport(cfg sensenovaPricingImportConfig, db *sql.DB, out io.Writer) error {
	fixture, err := fetchSensenovaPricingFixture(cfg)
	if err != nil {
		return err
	}
	records, err := parseSensenovaPricingCatalog(fixture)
	if err != nil {
		return err
	}
	records = dedupeOfficialPricingRecords(records)
	if len(records) == 0 {
		return fmt.Errorf("unexpected sensenova pricing content: no records")
	}
	if cfg.DryRun {
		_, err = fmt.Fprintf(out, "source=sensenova-pricing-import models=%d operator=%s dry_run=true\n", len(records), records[0].OperatorName)
		return err
	}
	if db == nil {
		return fmt.Errorf("db is required when dry-run=false")
	}
	if err := upsertOfficialPricingRecords(db, records, "sensenova-pricing-import"); err != nil {
		return err
	}
	var tableRows int
	if err := db.QueryRow(`SELECT COUNT(*) FROM region_pricing`).Scan(&tableRows); err != nil {
		return fmt.Errorf("count region_pricing: %w", err)
	}
	_, err = fmt.Fprintf(out, "source=sensenova-pricing-import models=%d operator=%s table_rows=%d dry_run=false\n", len(records), records[0].OperatorName, tableRows)
	return err
}

func fetchSensenovaPricingFixture(cfg sensenovaPricingImportConfig) (sensenovaPricingFixture, error) {
	if strings.TrimSpace(cfg.Fixture) != "" {
		data, err := os.ReadFile(cfg.Fixture)
		if err != nil {
			return sensenovaPricingFixture{}, fmt.Errorf("read fixture %s: %w", cfg.Fixture, err)
		}
		return splitSensenovaFixture(string(data))
	}

	docsHTML, err := fetchRenderedPricingPageWithChromium(cfg.DocsURL, cfg.Timeout)
	if err != nil {
		return sensenovaPricingFixture{}, fmt.Errorf("fetch docs render: %w", err)
	}
	modelsText, err := fetchSensenovaModelsBundle(cfg.ModelsURL, cfg.Timeout)
	if err != nil {
		return sensenovaPricingFixture{}, err
	}
	return sensenovaPricingFixture{DocsHTML: docsHTML, ModelsText: modelsText}, nil
}

func splitSensenovaFixture(raw string) (sensenovaPricingFixture, error) {
	parts := strings.SplitN(raw, sensenovaFixtureSplitMarker, 2)
	if len(parts) != 2 {
		return sensenovaPricingFixture{}, fmt.Errorf("unexpected sensenova fixture: missing models bundle marker")
	}
	docsHTML := strings.TrimSpace(parts[0])
	modelsText := strings.TrimSpace(parts[1])
	if docsHTML == "" || modelsText == "" {
		return sensenovaPricingFixture{}, fmt.Errorf("unexpected sensenova fixture: empty docs or models segment")
	}
	return sensenovaPricingFixture{DocsHTML: docsHTML, ModelsText: modelsText}, nil
}

func fetchSensenovaModelsBundle(modelsURL string, timeout time.Duration) (string, error) {
	client := &http.Client{Timeout: timeout}
	html, err := fetchRawPricingPage(modelsURL, "", client)
	if err != nil {
		return "", fmt.Errorf("fetch models page shell: %w", err)
	}
	scripts := sensenovaModelsScriptPattern.FindAllStringSubmatch(html, -1)
	if len(scripts) == 0 {
		return "", fmt.Errorf("unexpected sensenova models page: no chunk scripts found")
	}
	seen := make(map[string]struct{}, len(scripts))
	for _, match := range scripts {
		if len(match) != 2 {
			continue
		}
		scriptURL, err := resolveSensenovaAssetURL(modelsURL, match[1])
		if err != nil {
			continue
		}
		if _, ok := seen[scriptURL]; ok {
			continue
		}
		seen[scriptURL] = struct{}{}
		bundle, err := fetchRawPricingPage(scriptURL, "", client)
		if err != nil {
			continue
		}
		if sensenovaBundleConfirmsFreeBeta(bundle) {
			return bundle, nil
		}
	}
	return "", fmt.Errorf("unexpected sensenova models page: free-beta bundle not found")
}

func resolveSensenovaAssetURL(baseURL string, assetPath string) (string, error) {
	parsedBase, err := url.Parse(baseURL)
	if err != nil {
		return "", err
	}
	asset, err := url.Parse(assetPath)
	if err != nil {
		return "", err
	}
	return parsedBase.ResolveReference(asset).String(), nil
}

func sensenovaBundleConfirmsFreeBeta(raw string) bool {
	hasFree := strings.Contains(raw, "公测期完全免费开放") || strings.Contains(raw, "free during public beta")
	hasAllModels := strings.Contains(raw, "所有模型完全开放") || strings.Contains(raw, "all models included")
	return hasFree && hasAllModels
}

func fetchRenderedPricingPageWithChromium(pageURL string, timeout time.Duration) (string, error) {
	browserPath, err := lookupChromiumBinaryForSensenova()
	if err != nil {
		return "", err
	}
	ctx, cancel := context.WithTimeout(context.Background(), timeout)
	defer cancel()
	cmd := exec.CommandContext(ctx, browserPath,
		"--headless",
		"--no-sandbox",
		"--disable-gpu",
		"--virtual-time-budget=8000",
		"--dump-dom",
		pageURL,
	)
	cmd.Stderr = io.Discard
	out, err := cmd.Output()
	if ctx.Err() == context.DeadlineExceeded {
		return "", fmt.Errorf("chromium render timeout after %s", timeout)
	}
	if err != nil {
		return "", fmt.Errorf("chromium dump-dom: %w", err)
	}
	if len(out) == 0 {
		return "", fmt.Errorf("chromium dump-dom returned empty output")
	}
	return string(out), nil
}

func lookupChromiumBinaryForSensenova() (string, error) {
	for _, name := range []string{"chromium", "chromium-browser", "google-chrome", "google-chrome-stable"} {
		if path, err := exec.LookPath(name); err == nil {
			return path, nil
		}
	}
	return "", fmt.Errorf("no chromium-compatible browser found in PATH")
}

func parseSensenovaPricingCatalog(fixture sensenovaPricingFixture) ([]officialPricingRecord, error) {
	if !sensenovaBundleConfirmsFreeBeta(fixture.ModelsText) {
		return nil, fmt.Errorf("unexpected sensenova models bundle: missing public-beta free signal")
	}
	if !strings.Contains(fixture.DocsHTML, "GET https://token.sensenova.cn/v1/models") {
		return nil, fmt.Errorf("unexpected sensenova docs content: missing list models endpoint")
	}
	if !sensenovaPricingZeroPattern.MatchString(fixture.DocsHTML) {
		return nil, fmt.Errorf("unexpected sensenova docs content: missing zero pricing object example")
	}

	matches := sensenovaOverviewCardPattern.FindAllStringSubmatch(fixture.DocsHTML, -1)
	if len(matches) == 0 {
		return nil, fmt.Errorf("unexpected sensenova docs content: no model overview cards parsed")
	}

	providerNameCn, providerCountry, providerWebsite := providerMetadata("SenseTime")
	records := make([]officialPricingRecord, 0, len(matches))
	seenModelIDs := make(map[string]struct{}, len(matches))
	for _, match := range matches {
		if len(match) != 4 {
			continue
		}
		modelName := strings.TrimSpace(match[1])
		modelID := strings.TrimSpace(match[3])
		if modelName == "" || modelID == "" {
			continue
		}
		if _, ok := seenModelIDs[modelID]; ok {
			continue
		}
		seenModelIDs[modelID] = struct{}{}
		sectionID := sensenovaSectionIDForModel(modelID)
		section, err := extractHTMLSectionByID(fixture.DocsHTML, sectionID)
		if err != nil {
			return nil, err
		}
		providerName := sensenovaProviderName(modelID)
		providerCn, providerCountryCode, providerSite := providerNameCn, providerCountry, providerWebsite
		if providerName != "SenseTime" {
			providerCn, providerCountryCode, providerSite = providerMetadata(providerName)
		}
		records = append(records, officialPricingRecord{
			ModelID:         normalizeExternalID("sensenova", modelID),
			ModelName:       modelName,
			ProviderName:    providerName,
			ProviderNameCn:  providerCn,
			ProviderCountry: providerCountryCode,
			ProviderWebsite: providerSite,
			OperatorName:    "SenseNova API",
			OperatorNameCn:  "日日新开放平台",
			OperatorCountry: "CN",
			OperatorWebsite: defaultSensenovaDocsURL,
			OperatorType:    "official",
			Region:          "CN",
			Currency:        "CNY",
			InputPrice:      0,
			OutputPrice:     0,
			IsFree:          true,
			ContextLength:   sensenovaContextLength(modelID, section),
			SourceURL:       defaultSensenovaDocsURL,
			ModelSourceURL:  firstNonEmptyText(defaultSensenovaDocsURL+"#"+sectionID, defaultSensenovaDocsURL),
			DateConfidence:  "unknown",
			DateSourceKind:  "official_pricing",
			Modality:        sensenovaModality(modelID, section),
		})
	}
	if len(records) == 0 {
		return nil, fmt.Errorf("unexpected sensenova pricing content: empty records after parse")
	}
	return records, nil
}

func extractHTMLSectionByID(raw string, sectionID string) (string, error) {
	marker := fmt.Sprintf(`<section id="%s"`, sectionID)
	start := strings.Index(raw, marker)
	if start == -1 {
		return "", fmt.Errorf("unexpected sensenova docs content: missing section %s", sectionID)
	}
	remaining := raw[start:]
	next := strings.Index(remaining[len(marker):], "<section id=")
	if next == -1 {
		return remaining, nil
	}
	return remaining[:len(marker)+next], nil
}

func sensenovaSectionIDForModel(modelID string) string {
	switch modelID {
	case "sensenova-6.7-flash-lite":
		return "model-flash"
	case "sensenova-u1-fast":
		return "model-u1"
	case "deepseek-v4-flash":
		return "model-deepseek-v4-flash"
	default:
		return ""
	}
}

func sensenovaProviderName(modelID string) string {
	if strings.HasPrefix(strings.ToLower(strings.TrimSpace(modelID)), "deepseek") {
		return "DeepSeek"
	}
	return "SenseTime"
}

func sensenovaContextLength(modelID string, section string) int {
	switch modelID {
	case "sensenova-6.7-flash-lite", "deepseek-v4-flash":
		if strings.Contains(section, "上下文长度 256K tokens") || strings.Contains(section, "256K 上下文") {
			return 256 * 1024
		}
	}
	return 0
}

func sensenovaModality(modelID string, section string) string {
	switch modelID {
	case "sensenova-u1-fast":
		if strings.Contains(section, "/v1/images/generations") {
			return "image"
		}
		return "multimodal"
	case "sensenova-6.7-flash-lite":
		if strings.Contains(section, "图像输入理解") {
			return "multimodal"
		}
		return "text"
	default:
		return "text"
	}
}