// Package api 暴露 TCS-IPTV 的 HTTP 接口，串联 service 业务编排。
// 对应需求17（接口规范）与各业务需求。
package api

import (
	"net/http"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/tcs-iptv/tcs/internal/chain"
	"github.com/tcs-iptv/tcs/internal/httpx"
	"github.com/tcs-iptv/tcs/internal/model"
	"github.com/tcs-iptv/tcs/internal/service"
)

// Handler 持有业务服务。
type Handler struct {
	svc *service.Service
}

// NewHandler 创建 API 处理器。
func NewHandler(svc *service.Service) *Handler {
	return &Handler{svc: svc}
}

// Register 注册路由（受鉴权中间件保护的路由组由调用方组装）。
func (h *Handler) Register(rg *gin.RouterGroup) {
	rg.POST("/content/register", h.register)                // CP 送审上链（需求2）
	rg.POST("/content/csps-result", h.cspsResult)           // CSPS 合规审核（发码前，需求5）
	rg.POST("/content/issue", h.issue)                      // 审核通过后发码签发（需求3）
	rg.POST("/content/verify", h.verify)                    // 哈希验真（需求4/7）
	rg.POST("/content/transcoded", h.bindTranscoded)        // 转码版绑定（需求5）
	rg.POST("/content/ingest", h.ingest)                    // 媒资库入库（需求6）
	rg.POST("/content/publish", h.publish)                  // 发布给运营商（需求6）
	rg.POST("/content/inject", h.inject)                    // CDN 注入校验（需求7）
	rg.POST("/content/version-change", h.versionChange)     // 版本变更重审（需求12）
	rg.POST("/content/takedown", h.takedown)                // 应急下架（需求11）
	rg.POST("/content/takedown-episode", h.takedownEpisode) // 集级下架（只下架某集）
	rg.POST("/content/restore", h.restore)                  // 恢复上架整剧
	rg.POST("/content/restore-episode", h.restoreEpisode)   // 恢复上架某集
	rg.GET("/content/mappings", h.mappings)                 // 映射查询（需求11/17）
	rg.POST("/content/verify-episode", h.verifyEpisode)     // 集级验真（一剧多集）
	rg.GET("/content/episodes", h.listEpisodes)             // 列出集级哈希
	rg.GET("/content/reviews", h.listReviews)               // 送审待办队列（待审/待发码）
	rg.GET("/content/list", h.listContents)                 // 内容队列（待入库/待发布/待注入）
	rg.POST("/data/playback", h.reportPlayback)             // 播放数据回传（需求9）
	rg.GET("/data/playback-summary", h.playbackSummary)     // 按MA码聚合可信播放数据（需求9/21）
	rg.POST("/settlement/compute", h.computeSettlement)     // 基于可信播放数据分账（需求21）
}

func roleOf(c *gin.Context) chain.Role {
	return chain.Role(httpx.RoleFromContext(c))
}

// --- handlers ---

type episodeHashReq struct {
	Episode    int    `json:"episode"`
	FileSHA256 string `json:"file_sha256"`
	MerkleRoot string `json:"merkle_root"`
	Perceptual string `json:"perceptual_hash"`
	Duration   int    `json:"duration"`
	Resolution string `json:"resolution"`
}

type registerReq struct {
	Title        string           `json:"title"`
	EpisodeCount int              `json:"episode_count"`
	Category     string           `json:"category"`
	FileHash     string           `json:"file_sha256"`
	MerkleRoot   string           `json:"merkle_root"`
	Perceptual   string           `json:"perceptual_hash"`
	Episodes     []episodeHashReq `json:"episodes"`
	CPMediaID    string           `json:"cp_media_id"`
	CPName       string           `json:"cp_name"`
}

func (h *Handler) register(c *gin.Context) {
	var req registerReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	eps := make([]model.EpisodeHash, 0, len(req.Episodes))
	for _, e := range req.Episodes {
		eps = append(eps, model.EpisodeHash{
			Episode: e.Episode, FileSHA256: e.FileSHA256, MerkleRoot: e.MerkleRoot,
			Perceptual: e.Perceptual, Duration: e.Duration, Resolution: e.Resolution,
		})
	}
	res, err := h.svc.SubmitForReview(service.Submission{
		Title: req.Title, EpisodeCount: req.EpisodeCount, Category: req.Category,
		FileHash: req.FileHash, MerkleRoot: req.MerkleRoot, Perceptual: req.Perceptual,
		Episodes:  eps,
		CPMediaID: req.CPMediaID, CPName: req.CPName,
	})
	if err != nil {
		httpx.Error(c, http.StatusBadRequest, "REGISTER_FAILED", err.Error())
		return
	}
	httpx.Accepted(c, res)
}

type issueReq struct {
	ReviewID string `json:"review_id"`
	Issuer   string `json:"issuer"`
}

func (h *Handler) issue(c *gin.Context) {
	var req issueReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	res, err := h.svc.ApproveAndIssue(roleOf(c), req.ReviewID, req.Issuer)
	if err != nil {
		httpx.Error(c, http.StatusForbidden, "ISSUE_FAILED", err.Error())
		return
	}
	httpx.OK(c, res)
}

type verifyReq struct {
	MACode   string `json:"ma_code"`
	FileHash string `json:"file_sha256"`
}

func (h *Handler) verify(c *gin.Context) {
	var req verifyReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	res, err := h.svc.Verify(req.MACode, req.FileHash)
	if err != nil {
		// 验真不匹配也返回结果体，便于调用方据 match 处理
		httpx.Error(c, http.StatusBadRequest, "VERIFY_MISMATCH", err.Error())
		return
	}
	httpx.OK(c, res)
}

type cspsReq struct {
	ReviewID   string `json:"review_id"`
	Approved   bool   `json:"approved"`
	ReviewerID string `json:"reviewer_id"`
}

func (h *Handler) cspsResult(c *gin.Context) {
	var req cspsReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	if err := h.svc.ReviewCSPS(req.ReviewID, req.Approved, req.ReviewerID); err != nil {
		httpx.Error(c, http.StatusBadRequest, "CSPS_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"review_id": req.ReviewID, "approved": req.Approved})
}

type transcodedReq struct {
	CTID           string `json:"content_twin_id"`
	ParentFileHash string `json:"parent_file_hash"`
	TranscodedHash string `json:"transcoded_hash"`
	Format         string `json:"format"`
	Resolution     string `json:"resolution"`
	Version        string `json:"version"`
}

func (h *Handler) bindTranscoded(c *gin.Context) {
	var req transcodedReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	tx, err := h.svc.BindTranscoded(roleOf(c), req.CTID, req.ParentFileHash,
		req.TranscodedHash, req.Format, req.Resolution, req.Version)
	if err != nil {
		httpx.Error(c, http.StatusBadRequest, "TRANSCODE_BIND_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"tx_id": tx})
}

type ingestReq struct {
	MACode       string `json:"ma_code"`
	CTID         string `json:"content_twin_id"`
	MediaAssetID string `json:"media_asset_id"`
	LibName      string `json:"lib_name"`
}

func (h *Handler) ingest(c *gin.Context) {
	var req ingestReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	if err := h.svc.IngestToLibrary(roleOf(c), req.MACode, req.CTID, req.MediaAssetID, req.LibName); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INGEST_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"ma_code": req.MACode, "status": "in_library"})
}

type publishReq struct {
	MACode      string `json:"ma_code"`
	Certificate string `json:"certificate"`
}

func (h *Handler) publish(c *gin.Context) {
	var req publishReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	if err := h.svc.PublishToOperator(service.PublishRequest{MACode: req.MACode, Certificate: req.Certificate}); err != nil {
		httpx.Error(c, http.StatusBadRequest, "PUBLISH_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"ma_code": req.MACode, "status": "published"})
}

type injectReq struct {
	CTID        string `json:"content_twin_id"`
	MACode      string `json:"ma_code"`
	FileHash    string `json:"file_sha256"`
	OperatorID  string `json:"operator_id"`
	CDNEndpoint string `json:"cdn_endpoint"`
}

func (h *Handler) inject(c *gin.Context) {
	var req injectReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	res, err := h.svc.InjectToCDN(roleOf(c), req.CTID, req.MACode, req.FileHash, req.OperatorID, req.CDNEndpoint)
	if err != nil {
		httpx.Error(c, http.StatusBadRequest, "INJECT_REJECTED", err.Error())
		return
	}
	httpx.OK(c, res)
}

type versionChangeReq struct {
	CTID        string   `json:"content_twin_id"`
	Reason      string   `json:"reason"`
	PrevHash    string   `json:"prev_hash"`
	NewHash     string   `json:"new_hash"`
	OldSegments []string `json:"old_segments"`
	NewSegments []string `json:"new_segments"`
}

func (h *Handler) versionChange(c *gin.Context) {
	var req versionChangeReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	episodes, err := h.svc.ReportVersionChange(req.CTID, req.Reason, req.PrevHash, req.NewHash, req.OldSegments, req.NewSegments)
	if err != nil {
		httpx.Error(c, http.StatusBadRequest, "VERSION_CHANGE_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"reaudit_required": true, "affected_episodes": episodes})
}

type takedownReq struct {
	MACode string `json:"ma_code"`
	Reason string `json:"reason"`
}

func (h *Handler) takedown(c *gin.Context) {
	var req takedownReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	res, err := h.svc.Takedown(roleOf(c), req.MACode, req.Reason)
	if err != nil {
		httpx.Error(c, http.StatusForbidden, "TAKEDOWN_FAILED", err.Error())
		return
	}
	httpx.OK(c, res)
}

type takedownEpisodeReq struct {
	MACode  string `json:"ma_code"`
	Episode int    `json:"episode"`
	Reason  string `json:"reason"`
}

func (h *Handler) takedownEpisode(c *gin.Context) {
	var req takedownEpisodeReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	if err := h.svc.TakedownEpisode(roleOf(c), req.MACode, req.Episode, req.Reason); err != nil {
		httpx.Error(c, http.StatusForbidden, "TAKEDOWN_EPISODE_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"ma_code": req.MACode, "episode": req.Episode, "revoked": true})
}

func (h *Handler) restore(c *gin.Context) {
	var req takedownReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	if err := h.svc.Restore(roleOf(c), req.MACode); err != nil {
		httpx.Error(c, http.StatusForbidden, "RESTORE_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"ma_code": req.MACode, "status": "published"})
}

func (h *Handler) restoreEpisode(c *gin.Context) {
	var req takedownEpisodeReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	if err := h.svc.RestoreEpisode(roleOf(c), req.MACode, req.Episode); err != nil {
		httpx.Error(c, http.StatusForbidden, "RESTORE_EPISODE_FAILED", err.Error())
		return
	}
	httpx.OK(c, gin.H{"ma_code": req.MACode, "episode": req.Episode, "revoked": false})
}

func (h *Handler) mappings(c *gin.Context) {
	maCode := c.Query("ma_code")
	if maCode == "" {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", "缺少 ma_code")
		return
	}
	res, err := h.svc.QueryMappings(maCode)
	if err != nil {
		httpx.Error(c, http.StatusNotFound, "NOT_FOUND", err.Error())
		return
	}
	httpx.OK(c, res)
}

type verifyEpisodeReq struct {
	MACode   string `json:"ma_code"`
	Episode  int    `json:"episode"`
	FileHash string `json:"file_sha256"`
}

func (h *Handler) verifyEpisode(c *gin.Context) {
	var req verifyEpisodeReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	res, err := h.svc.VerifyEpisode(req.MACode, req.Episode, req.FileHash)
	if err != nil {
		httpx.Error(c, http.StatusBadRequest, "VERIFY_MISMATCH", err.Error())
		return
	}
	httpx.OK(c, res)
}

func (h *Handler) listEpisodes(c *gin.Context) {
	maCode := c.Query("ma_code")
	if maCode == "" {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", "缺少 ma_code")
		return
	}
	eps, err := h.svc.ListEpisodes(maCode)
	if err != nil {
		httpx.Error(c, http.StatusNotFound, "NOT_FOUND", err.Error())
		return
	}
	httpx.OK(c, gin.H{"ma_code": maCode, "episodes": eps, "count": len(eps)})
}

func (h *Handler) listReviews(c *gin.Context) {
	httpx.OK(c, gin.H{"reviews": h.svc.ListReviews(c.Query("status"))})
}

func (h *Handler) listContents(c *gin.Context) {
	list, err := h.svc.ListContentsByStatus(c.Query("status"))
	if err != nil {
		httpx.Error(c, http.StatusInternalServerError, "INTERNAL_ERROR", err.Error())
		return
	}
	httpx.OK(c, gin.H{"contents": list, "count": len(list)})
}

// ---- 二期：播放数据回传与分账（需求9/21） ----

type playbackReq struct {
	PlatformID string `json:"platform_id"`
	Batch      []struct {
		MACode      string `json:"ma_code"`
		Episode     int    `json:"episode"`
		UserHash    string `json:"user_hash"`
		EventType   string `json:"event_type"`
		DurationSec int    `json:"duration_sec"`
		RevenueCent int64  `json:"revenue_cent"`
	} `json:"batch"`
}

func (h *Handler) reportPlayback(c *gin.Context) {
	var req playbackReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	events := make([]model.PlaybackEvent, 0, len(req.Batch))
	for _, b := range req.Batch {
		events = append(events, model.PlaybackEvent{
			MACode: b.MACode, Episode: b.Episode, PlatformID: req.PlatformID,
			UserHash: b.UserHash, EventType: model.PlaybackEventType(b.EventType),
			DurationSec: b.DurationSec, RevenueCent: b.RevenueCent, EventTime: time.Now(),
		})
	}
	accepted, rejected := h.svc.ReportPlayback(events)
	httpx.OK(c, gin.H{"accepted": accepted, "rejected": rejected})
}

func (h *Handler) playbackSummary(c *gin.Context) {
	maCode := c.Query("ma_code")
	if maCode == "" {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", "缺少 ma_code")
		return
	}
	httpx.OK(c, h.svc.PlaybackSummary(maCode))
}

type settlementReq struct {
	MACode string `json:"ma_code"`
	Period string `json:"period"`
}

func (h *Handler) computeSettlement(c *gin.Context) {
	var req settlementReq
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.Error(c, http.StatusBadRequest, "INVALID_REQUEST", err.Error())
		return
	}
	st, err := h.svc.ComputeSettlement(req.MACode, req.Period)
	if err != nil {
		httpx.Error(c, http.StatusBadRequest, "SETTLEMENT_FAILED", err.Error())
		return
	}
	httpx.OK(c, st)
}