module Web.Controller.Api.V2.OpenApi where

-- GET /api/v2/openapi.json  — OpenAPI 3.1 spec with live type registry enums
-- GET /api/v2/openapi.yaml  — YAML convenience alias
-- GET /api/v2/docs          — Swagger UI

import Web.Types
import Generated.Types
import IHP.Prelude
import IHP.ControllerPrelude
import Data.Aeson (object, (.=), Array, toJSON)
import qualified Data.Aeson as A
import qualified Data.Vector as V
import qualified Data.Text as T
import qualified Data.Text.Encoding as TE
import qualified Data.Yaml as Yaml  -- yaml package
import qualified Data.ByteString.Lazy as LBS
import Application.Helper.TypeRegistry
    ( activeWidgetTypes, activeEventTypes, activeAnnotationCategories )
import Network.HTTP.Types (status200)

instance Controller ApiV2OpenApiController where

    action ApiV2OpenApiJsonAction = do
        spec <- buildOpenApiSpec
        respondAndExit $ responseLBS status200
            [("Content-Type", "application/json")]
            (A.encode spec)

    action ApiV2OpenApiYamlAction = do
        spec <- buildOpenApiSpec
        let yaml = Yaml.encode spec
        respondAndExit $ responseLBS status200
            [("Content-Type", "application/yaml")]
            (LBS.fromStrict yaml)

    action ApiV2DocsAction = do
        respondAndExit $ responseLBS status200
            [("Content-Type", "text/html; charset=utf-8")]
            swaggerUiHtml

-- | Build the full OpenAPI 3.1 document from live registry data.
buildOpenApiSpec :: (?modelContext :: ModelContext) => IO Value
buildOpenApiSpec = do
    (fwWidgetTypes, ownedWidgetTypes) <- activeWidgetTypes
    let allWidgetTypes = fwWidgetTypes ++ ownedWidgetTypes
    eventTypes  <- activeEventTypes
    annCats     <- activeAnnotationCategories

    let wtEnum  = toJSON $ map (.name) allWidgetTypes
    let etEnum  = toJSON $ map (.name) eventTypes
    let acEnum  = toJSON $ map (.name) annCats

    pure $ object
        [ "openapi" .= ("3.1.0" :: Text)
        , "info" .= object
            [ "title"       .= ("Interaction Hub Framework API" :: Text)
            , "version"     .= ("2.0" :: Text)
            , "description" .= ("IHF external API v2. For the human-readable contract see /contracts/functional/interaction-reporting-v1.md" :: Text)
            ]
        , "x-ihf-contract" .= ("/contracts/functional/interaction-reporting-v1.md" :: Text)
        , "servers" .= [object ["url" .= ("/api/v2" :: Text)]]
        , "paths" .= buildPaths
        , "components" .= object
            [ "schemas" .= object
                [ "WidgetType" .= object
                    [ "type" .= ("string" :: Text)
                    , "enum" .= wtEnum
                    ]
                , "EventType" .= object
                    [ "type" .= ("string" :: Text)
                    , "enum" .= etEnum
                    ]
                , "AnnotationCategory" .= object
                    [ "type" .= ("string" :: Text)
                    , "enum" .= acEnum
                    ]
                , "PaginationMeta" .= object
                    [ "type" .= ("object" :: Text)
                    , "properties" .= object
                        [ "page"     .= object ["type" .= ("integer" :: Text)]
                        , "per_page" .= object ["type" .= ("integer" :: Text)]
                        , "total"    .= object ["type" .= ("integer" :: Text)]
                        ]
                    ]
                , "Widget" .= widgetSchema
                , "InteractionEvent" .= interactionEventSchema
                , "Annotation" .= annotationSchema
                , "RequirementCandidate" .= rcSchema
                , "DecisionRecord" .= drSchema
                , "DeploymentRecord" .= depSchema
                , "OutcomeSignal" .= sigSchema
                , "OutcomeCorrelation" .= outcomeCorrelationSchema
                , "PatternPerformanceRecord" .= patternPerformanceSchema
                , "InstitutionalKnowledgeEntry" .= institutionalKnowledgeSchema
                ]
            , "securitySchemes" .= object
                [ "BearerAuth" .= object
                    [ "type"         .= ("http" :: Text)
                    , "scheme"       .= ("bearer" :: Text)
                    , "description"  .= ("API key or OAuth token obtained via POST /api/v2/token" :: Text)
                    ]
                ]
            ]
        , "security" .= [object ["BearerAuth" .= ([] :: [Text])]]
        ]

buildPaths :: Value
buildPaths = object
    [ "/widgets" .= getListPath "Widget"
    , "/widgets/{id}" .= getShowPath "Widget"
    , "/interaction-events" .= object
        [ "get"  .= listOp "InteractionEvent"
            [ ("widgetId",  "string", "uuid")
            , ("eventType", "string", "")
            ]
        , "post" .= writeOp "InteractionEvent" "CreateInteractionEventRequest"
        ]
    , "/annotations" .= object
        [ "get"  .= listOp "Annotation"
            [ ("widgetId",  "string", "uuid")
            , ("category",  "string", "")
            ]
        , "post" .= writeOp "Annotation" "CreateAnnotationRequest"
        ]
    , "/requirement-candidates" .= getListPath "RequirementCandidate"
    , "/requirement-candidates/{id}" .= getShowPath "RequirementCandidate"
    , "/decision-records" .= getListPath "DecisionRecord"
    , "/decision-records/{id}" .= getShowPath "DecisionRecord"
    , "/deployment-records" .= getListPath "DeploymentRecord"
    , "/deployment-records/{id}" .= getShowPath "DeploymentRecord"
    , "/outcome-signals" .= getListPath "OutcomeSignal"
    , "/outcome-signals/{id}" .= getShowPath "OutcomeSignal"
    , "/widget-types" .= publicListPath "WidgetTypeRegistry"
    , "/event-types" .= publicListPath "EventTypeRegistry"
    , "/annotation-categories" .= publicListPath "AnnotationCategoryRegistry"
    , "/token" .= tokenPath
    -- Phase 10 — Hub Registry and Widget Marketplace
    , "/hub-registry" .= getListPath "HubRegistryEntry"
    , "/hub-registry/{hubId}" .= getShowPath "HubRegistryEntry"
    , "/widget-patterns" .= getListPath "WidgetPattern"
    , "/widget-patterns/{id}" .= getShowPath "WidgetPattern"
    , "/widget-patterns/{id}/adopt" .= object
        [ "post" .= writeOp "PatternAdoption" "AdoptPatternRequest"
        ]
    ]

getListPath :: Text -> Value
getListPath schemaName = object
    [ "get" .= listOp schemaName [] ]

getShowPath :: Text -> Value
getShowPath schemaName = object
    [ "get" .= showOp schemaName ]

listOp :: Text -> [(Text, Text, Text)] -> Value
listOp schemaName extraParams = object
    [ "summary"    .= ("List " <> schemaName)
    , "security"   .= [object ["BearerAuth" .= ([] :: [Text])]]
    , "parameters" .= (pageParams ++ map toParam extraParams)
    , "responses"  .= object
        [ "200" .= object
            [ "description" .= ("OK" :: Text)
            , "content" .= object
                [ "application/json" .= object
                    [ "schema" .= object
                        [ "type" .= ("object" :: Text)
                        , "properties" .= object
                            [ "data" .= object
                                [ "type" .= ("array" :: Text)
                                , "items" .= object ["$ref" .= ("#/components/schemas/" <> schemaName)]
                                ]
                            , "meta" .= object ["$ref" .= ("#/components/schemas/PaginationMeta" :: Text)]
                            ]
                        ]
                    ]
                ]
            ]
        , "401" .= object ["description" .= ("Unauthorized" :: Text)]
        ]
    ]
  where
    toParam (name, typ, fmt) = object $
        [ "name" .= name, "in" .= ("query" :: Text)
        , "schema" .= object (["type" .= typ] ++ if fmt /= "" then [("format", A.String fmt)] else [])
        ]

showOp :: Text -> Value
showOp schemaName = object
    [ "summary"    .= ("Get " <> schemaName)
    , "security"   .= [object ["BearerAuth" .= ([] :: [Text])]]
    , "parameters" .= [object ["name" .= ("id" :: Text), "in" .= ("path" :: Text), "required" .= True, "schema" .= object ["type" .= ("string" :: Text), "format" .= ("uuid" :: Text)]]]
    , "responses"  .= object
        [ "200" .= object
            [ "description" .= ("OK" :: Text)
            , "content" .= object
                [ "application/json" .= object
                    ["schema" .= object ["$ref" .= ("#/components/schemas/" <> schemaName)]]
                ]
            ]
        , "401" .= object ["description" .= ("Unauthorized" :: Text)]
        , "404" .= object ["description" .= ("Not found" :: Text)]
        ]
    ]

writeOp :: Text -> Text -> Value
writeOp schemaName _reqSchema = object
    [ "summary"    .= ("Create " <> schemaName)
    , "security"   .= [object ["BearerAuth" .= ([] :: [Text])]]
    , "requestBody" .= object
        [ "required" .= True
        , "content" .= object
            [ "application/json" .= object
                ["schema" .= object ["$ref" .= ("#/components/schemas/" <> schemaName)]]
            ]
        ]
    , "responses"  .= object
        [ "201" .= object ["description" .= ("Created" :: Text)]
        , "401" .= object ["description" .= ("Unauthorized" :: Text)]
        , "422" .= object ["description" .= ("Validation error" :: Text)]
        ]
    ]

publicListPath :: Text -> Value
publicListPath schemaName = object
    [ "get" .= object
        [ "summary"    .= ("List registered " <> schemaName <> " values" :: Text)
        , "responses"  .= object
            [ "200" .= object ["description" .= ("OK" :: Text)] ]
        ]
    ]

tokenPath :: Value
tokenPath = object
    [ "post" .= object
        [ "summary" .= ("Obtain OAuth access token (client credentials)" :: Text)
        , "requestBody" .= object
            [ "required" .= True
            , "content" .= object
                [ "application/x-www-form-urlencoded" .= object
                    [ "schema" .= object
                        [ "type" .= ("object" :: Text)
                        , "properties" .= object
                            [ "grant_type"    .= object ["type" .= ("string" :: Text), "enum" .= ["client_credentials" :: Text]]
                            , "client_id"     .= object ["type" .= ("string" :: Text), "format" .= ("uuid" :: Text)]
                            , "client_secret" .= object ["type" .= ("string" :: Text)]
                            , "scope"         .= object ["type" .= ("string" :: Text)]
                            ]
                        ]
                    ]
                ]
            ]
        , "responses" .= object
            [ "200" .= object ["description" .= ("Access token issued" :: Text)]
            , "400" .= object ["description" .= ("Invalid request or credentials" :: Text)]
            ]
        ]
    ]

pageParams :: [Value]
pageParams =
    [ object ["name" .= ("page" :: Text),     "in" .= ("query" :: Text), "schema" .= object ["type" .= ("integer" :: Text)]]
    , object ["name" .= ("per_page" :: Text), "in" .= ("query" :: Text), "schema" .= object ["type" .= ("integer" :: Text)]]
    ]

-- Schemas for all resource types

widgetSchema :: Value
widgetSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"           .= uuidProp
        , "hubId"        .= uuidProp
        , "name"         .= strProp
        , "widgetType"   .= object ["$ref" .= ("#/components/schemas/WidgetType" :: Text)]
        , "capabilityRef" .= strProp
        , "viewContext"  .= strProp
        , "policyScope"  .= strProp
        , "status"       .= strProp
        , "version"      .= object ["type" .= ("integer" :: Text)]
        , "createdAt"    .= object ["type" .= ("string" :: Text), "format" .= ("date-time" :: Text)]
        ]
    ]

interactionEventSchema :: Value
interactionEventSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"             .= uuidProp
        , "widgetId"       .= uuidProp
        , "eventType"      .= object ["$ref" .= ("#/components/schemas/EventType" :: Text)]
        , "actorId"        .= uuidProp
        , "actorType"      .= strProp
        , "viewContextRef" .= strProp
        , "metadata"       .= object ["type" .= ("object" :: Text)]
        , "occurredAt"     .= dtProp
        ]
    ]

annotationSchema :: Value
annotationSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"        .= uuidProp
        , "widgetId"  .= uuidProp
        , "parentId"  .= uuidProp
        , "body"      .= strProp
        , "category"  .= object ["$ref" .= ("#/components/schemas/AnnotationCategory" :: Text)]
        , "severity"  .= strProp
        , "threadId"  .= uuidProp
        , "actorId"   .= uuidProp
        , "actorType" .= strProp
        , "createdAt" .= dtProp
        ]
    ]

rcSchema :: Value
rcSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"          .= uuidProp
        , "title"       .= strProp
        , "description" .= strProp
        , "sourceWidgetId" .= uuidProp
        , "category"    .= strProp
        , "status"      .= strProp
        , "createdAt"   .= dtProp
        ]
    ]

drSchema :: Value
drSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"           .= uuidProp
        , "title"        .= strProp
        , "rationale"    .= strProp
        , "outcome"      .= strProp
        , "requirementId" .= uuidProp
        , "candidateId"  .= uuidProp
        , "decidedAt"    .= dtProp
        , "notes"        .= strProp
        , "createdAt"    .= dtProp
        ]
    ]

depSchema :: Value
depSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"          .= uuidProp
        , "decisionId"  .= uuidProp
        , "versionRef"  .= strProp
        , "deployedAt"  .= dtProp
        , "notes"       .= strProp
        , "createdAt"   .= dtProp
        ]
    ]

sigSchema :: Value
sigSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"           .= uuidProp
        , "widgetId"     .= uuidProp
        , "deploymentId" .= uuidProp
        , "signalType"   .= strProp
        , "value"        .= object ["type" .= ("number" :: Text)]
        , "observedAt"   .= dtProp
        ]
    ]

outcomeCorrelationSchema :: Value
outcomeCorrelationSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"                 .= uuidProp
        , "hubId"              .= uuidProp
        , "annotationCategory" .= strProp
        , "correlationType"    .= strProp
        , "correlationScore"   .= object ["type" .= ("number" :: Text)]
        , "sampleCount"        .= object ["type" .= ("integer" :: Text)]
        , "computedAt"         .= dtProp
        ]
    ]

patternPerformanceSchema :: Value
patternPerformanceSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"                   .= uuidProp
        , "widgetPatternId"      .= uuidProp
        , "hubId"                .= uuidProp
        , "adoptionCount"        .= object ["type" .= ("integer" :: Text)]
        , "positiveOutcomeCount" .= object ["type" .= ("integer" :: Text)]
        , "totalOutcomeCount"    .= object ["type" .= ("integer" :: Text)]
        , "positiveOutcomeRate"  .= object ["type" .= ("number" :: Text)]
        , "meanOutcomeValue"     .= object ["type" .= ("number" :: Text)]
        , "outcomeRank"          .= object ["type" .= ("integer" :: Text)]
        , "calibratedAt"         .= dtProp
        ]
    ]

institutionalKnowledgeSchema :: Value
institutionalKnowledgeSchema = object
    [ "type" .= ("object" :: Text)
    , "properties" .= object
        [ "id"               .= uuidProp
        , "hubId"            .= uuidProp
        , "decisionRecordId" .= uuidProp
        , "summary"          .= strProp
        , "tags"             .= object ["type" .= ("array" :: Text)]
        , "createdAt"        .= dtProp
        , "updatedAt"        .= dtProp
        ]
    ]

uuidProp :: Value
uuidProp = object ["type" .= ("string" :: Text), "format" .= ("uuid" :: Text)]

strProp :: Value
strProp = object ["type" .= ("string" :: Text)]

dtProp :: Value
dtProp = object ["type" .= ("string" :: Text), "format" .= ("date-time" :: Text)]

-- | Embedded Swagger UI HTML using CDN assets (no build step required)
swaggerUiHtml :: LBS.ByteString
swaggerUiHtml = LBS.fromStrict $ TE.encodeUtf8 swaggerUiHtmlText

swaggerUiHtmlText :: Text
swaggerUiHtmlText =
    "<!DOCTYPE html><html lang=\"en\"><head><meta charset=\"UTF-8\" />" <>
    "<title>IHF API v2 \x2014 Documentation</title>" <>
    "<link rel=\"stylesheet\" href=\"https://unpkg.com/swagger-ui-dist@5/swagger-ui.css\" />" <>
    "</head><body>" <>
    "<div id=\"swagger-ui\"></div>" <>
    "<script src=\"https://unpkg.com/swagger-ui-dist@5/swagger-ui-bundle.js\"></script>" <>
    "<script>window.onload=function(){SwaggerUIBundle({" <>
    "url:\"/api/v2/openapi.json\"," <>
    "dom_id:\"#swagger-ui\"," <>
    "presets:[SwaggerUIBundle.presets.apis,SwaggerUIBundle.SwaggerUIStandalonePreset]," <>
    "layout:\"StandaloneLayout\"" <>
    "});}</script>" <>
    "</body></html>"