package api

import (
	"errors"
	"io"
	"log"
	"net/http"

	"github.com/gin-gonic/gin"

	"oci-portal/internal/oci"
	"oci-portal/internal/service"
)

// idpIconResponse 是图标上传响应;fileName 为域存储内标识,留作后续清理。
type idpIconResponse struct {
	URL      string `json:"url"`
	FileName string `json:"fileName"`
}

type idpSetupWarning struct {
	Code            string `json:"code"`
	Message         string `json:"message"`
	ResourceCreated bool   `json:"resourceCreated"`
	RequestID       string `json:"requestId"`
}

type createIdpResponse struct {
	oci.IdentityProviderInfo
	SetupWarning *idpSetupWarning `json:"setupWarning,omitempty"`
}

// @Summary  上传身份提供商图标
// @Description 上传到身份域公共图片存储(/storage/v1/Images),返回可填入 iconUrl 的公网地址
// @Tags     租户 IAM
// @Accept   multipart/form-data
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Param    file formData file true "图标文件(png/jpg/jpeg/gif/svg/webp/ico,≤1MB)"
// @Success  200 {object} idpIconResponse
// @Failure  400 {object} map[string]string "缺文件字段、文件为空或文件名非法"
// @Failure  413 {object} map[string]string "文件超过 1MB"
// @Failure  415 {object} map[string]string "扩展名不支持或与文件内容不符"
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/idp-icons [post]
func (h *ociConfigHandler) uploadIdpIcon(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	file, header, err := c.Request.FormFile("file")
	if err != nil {
		status, msg := iconFormStatus(err)
		c.JSON(status, gin.H{"error": msg})
		return
	}
	defer file.Close()
	data, err := io.ReadAll(file) // 请求体总量由路由级 bodyLimit 兜底
	if err != nil {
		status, msg := iconFormStatus(err)
		c.JSON(status, gin.H{"error": msg})
		return
	}
	url, fileName, err := h.svc.UploadIdpIcon(c.Request.Context(), id, c.Query("domainId"), header.Filename, data)
	if err != nil {
		respondIdpIconErr(c, err)
		return
	}
	c.JSON(http.StatusOK, idpIconResponse{URL: url, FileName: fileName})
}

// @Summary  删除身份提供商图标
// @Description 使用上传响应中的 fileName 删除身份域公开图片;404 按已删除处理
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Param    fileName query string true "上传响应返回的 IdP 图标存储标识(images/idp-icon-<32hex>.<ext>)"
// @Success  204 "无内容"
// @Failure  400 {object} map[string]string "fileName 缺失或不是本服务生成的 IdP 图标标识"
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/idp-icons [delete]
func (h *ociConfigHandler) deleteIdpIcon(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	if err := h.svc.DeleteIdpIcon(c.Request.Context(), id, c.Query("domainId"), c.Query("fileName")); err != nil {
		respondIdpIconErr(c, err)
		return
	}
	c.Status(http.StatusNoContent)
}

// iconFormStatus 区分请求体超限(413)与表单缺失/损坏(400)。
func iconFormStatus(err error) (int, string) {
	var mbe *http.MaxBytesError
	if errors.As(err, &mbe) {
		return http.StatusRequestEntityTooLarge, "请求体超出上限(图标最大 1MB)"
	}
	return http.StatusBadRequest, "缺少文件字段 file"
}

// respondIdpIconErr 把图标校验哨兵错误映射为语义状态码,其余走统一错误边界。
func respondIdpIconErr(c *gin.Context, err error) {
	switch {
	case errors.Is(err, service.ErrIdpIconTooLarge):
		c.JSON(http.StatusRequestEntityTooLarge, gin.H{"error": "图标不能超过 1MB"})
	case errors.Is(err, service.ErrIdpIconBadType):
		c.JSON(http.StatusUnsupportedMediaType, gin.H{"error": "扩展名不支持或与文件内容不符"})
	case errors.Is(err, service.ErrIdpIconEmpty):
		c.JSON(http.StatusBadRequest, gin.H{"error": "文件为空"})
	case errors.Is(err, service.ErrIdpIconBadName):
		c.JSON(http.StatusBadRequest, gin.H{"error": "图标文件名非法"})
	default:
		respondError(c, err)
	}
}

// ---- Federation：SAML IdP 与 sign-on 免 MFA ----

// createIdpRequest 的映射 / JIT 字段全部可缺省：布尔用指针区分「未传」，
// 缺省即控制台默认（JIT 开启建用户不更新、分配 Administrators 组、
// 名称 ID 格式无、NameID 映射用户名）。
type createIdpRequest struct {
	Name        string `json:"name" binding:"required"`
	Metadata    string `json:"metadata" binding:"required"`
	Description string `json:"description"`
	IconURL     string `json:"iconUrl"`

	NameIDFormat       string `json:"nameIdFormat"`
	AssertionAttribute string `json:"assertionAttribute"`
	UserStoreAttribute string `json:"userStoreAttribute"`

	JitEnabled          *bool `json:"jitEnabled"`
	JitCreate           *bool `json:"jitCreate"`
	JitUpdate           *bool `json:"jitUpdate"`
	JitAssignAdminGroup *bool `json:"jitAssignAdminGroup"`
	JitMapEmail         bool  `json:"jitMapEmail"`
}

func boolOr(v *bool, def bool) bool {
	if v == nil {
		return def
	}
	return *v
}

// @Summary  身份提供商列表
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Success  200 {array} oci.IdentityProviderInfo
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/identity-providers [get]
func (h *ociConfigHandler) listIdentityProviders(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	idps, err := h.svc.IdentityProviders(c.Request.Context(), id, c.Query("domainId"))
	if err != nil {
		respondError(c, err)
		return
	}
	c.JSON(http.StatusOK, idps)
}

// @Summary  创建身份提供商(SAML)
// @Description 创建禁用态 IdP；若 IdP 已创建但 JIT 后置配置失败且回滚无法确认，仍返回 201，并在 setupWarning 中标明部分成功
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Param    body body createIdpRequest true "请求体"
// @Success  201 {object} createIdpResponse
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/identity-providers [post]
func (h *ociConfigHandler) createIdentityProvider(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	var req createIdpRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	idp, err := h.svc.CreateIdentityProvider(c.Request.Context(), id, c.Query("domainId"), oci.CreateIdpInput{
		Name:                req.Name,
		Metadata:            req.Metadata,
		Description:         req.Description,
		IconURL:             req.IconURL,
		NameIDFormat:        req.NameIDFormat,
		AssertionAttribute:  req.AssertionAttribute,
		UserStoreAttribute:  req.UserStoreAttribute,
		JitEnabled:          boolOr(req.JitEnabled, true),
		JitCreate:           boolOr(req.JitCreate, true),
		JitUpdate:           boolOr(req.JitUpdate, false),
		JitAssignAdminGroup: boolOr(req.JitAssignAdminGroup, true),
		JitMapEmail:         req.JitMapEmail,
	})
	respondCreateIdpResult(c, idp, err)
}

func respondCreateIdpResult(c *gin.Context, idp oci.IdentityProviderInfo, err error) {
	if err == nil {
		c.JSON(http.StatusCreated, createIdpResponse{IdentityProviderInfo: idp})
		return
	}
	var partial *oci.PartialIdentityProviderCreateError
	if !errors.As(err, &partial) {
		respondError(c, err)
		return
	}
	requestID := logPartialIdpCreate(c, partial)
	c.JSON(http.StatusCreated, createIdpResponse{
		IdentityProviderInfo: partial.IdentityProvider,
		SetupWarning: &idpSetupWarning{
			Code: oci.IdpSetupWarningCode, Message: "JIT 配置未完成，自动回滚状态无法确认，请刷新列表检查",
			ResourceCreated: true, RequestID: requestID,
		},
	})
}

func logPartialIdpCreate(c *gin.Context, partial *oci.PartialIdentityProviderCreateError) string {
	requestID := newRequestID()
	detail := errors.Unwrap(partial)
	if detail == nil {
		detail = partial
	}
	log.Printf("[WARN %s] %s %s: partial IdP create: %v", requestID, c.Request.Method, requestPath(c), detail)
	return requestID
}

// @Summary  激活身份提供商
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Param    idpId path string true "idpId"
// @Param    body body object true "请求体(见接口说明)"
// @Success  200 {object} oci.IdentityProviderInfo
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/identity-providers/{idpId}/activate [post]
func (h *ociConfigHandler) activateIdentityProvider(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	var req struct {
		Enabled *bool `json:"enabled" binding:"required"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	idp, err := h.svc.SetIdentityProviderEnabled(c.Request.Context(), id, c.Query("domainId"), c.Param("idpId"), *req.Enabled)
	if err != nil {
		respondError(c, err)
		return
	}
	c.JSON(http.StatusOK, idp)
}

// @Summary  删除身份提供商
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Param    idpId path string true "idpId"
// @Success  204 "无内容"
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/identity-providers/{idpId} [delete]
func (h *ociConfigHandler) deleteIdentityProvider(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	if err := h.svc.DeleteIdentityProvider(c.Request.Context(), id, c.Query("domainId"), c.Param("idpId")); err != nil {
		respondError(c, err)
		return
	}
	c.Status(http.StatusNoContent)
}

// @Summary  下载 SAML 元数据
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Success  200 {file} file "SAML 元数据 XML(附件下载)"
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/saml-metadata [get]
func (h *ociConfigHandler) downloadSamlMetadata(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	metadata, err := h.svc.DomainSamlMetadata(c.Request.Context(), id, c.Query("domainId"))
	if err != nil {
		respondError(c, err)
		return
	}
	c.Header("Content-Disposition", `attachment; filename="oci-domain-saml-metadata.xml"`)
	c.Data(http.StatusOK, "application/xml", metadata)
}

// @Summary  单点登录规则列表
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Success  200 {array} oci.SignOnRuleInfo
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/sign-on-rules [get]
func (h *ociConfigHandler) listSignOnRules(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	rules, err := h.svc.ConsoleSignOnRules(c.Request.Context(), id, c.Query("domainId"))
	if err != nil {
		respondError(c, err)
		return
	}
	c.JSON(http.StatusOK, rules)
}

// @Summary  创建 MFA 豁免规则
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Param    body body object true "请求体(见接口说明)"
// @Success  201 {object} oci.SignOnRuleInfo
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/sign-on-exemptions [post]
func (h *ociConfigHandler) createMfaExemption(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	var req struct {
		IdentityProviderID string `json:"identityProviderId" binding:"required"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	rule, err := h.svc.CreateMfaExemption(c.Request.Context(), id, c.Query("domainId"), req.IdentityProviderID)
	if err != nil {
		respondError(c, err)
		return
	}
	c.JSON(http.StatusCreated, rule)
}

// @Summary  删除 MFA 豁免规则
// @Tags     租户 IAM
// @Param    id path int true "配置 ID"
// @Param    domainId query string false "身份域 OCID(缺省 Default 域)"
// @Param    ruleId path string true "ruleId"
// @Success  204 "无内容"
// @Security BearerAuth
// @Router   /api/v1/oci-configs/{id}/sign-on-exemptions/{ruleId} [delete]
func (h *ociConfigHandler) deleteMfaExemption(c *gin.Context) {
	id, ok := pathID(c)
	if !ok {
		return
	}
	if err := h.svc.DeleteMfaExemption(c.Request.Context(), id, c.Query("domainId"), c.Param("ruleId")); err != nil {
		respondError(c, err)
		return
	}
	c.Status(http.StatusNoContent)
}