module Web.View.DecisionRecords.Show where

import Web.Types
import Generated.Types
import IHP.Prelude
import IHP.ViewPrelude
import Web.Routes ()
import Data.Int (Int16)

data ShowView = ShowView
    { record            :: !DecisionRecord
    , policyRefs        :: ![PolicyReference]
    , implRefs          :: ![ImplementationChangeReference]
    , deploymentRecords :: ![DeploymentRecord]
    , evaluations       :: ![ChangeEvaluation]
    , mRequirement      :: !(Maybe Requirement)
    , mCandidate        :: !(Maybe RequirementCandidate)
    , users             :: ![User]
    }

instance View ShowView where
    html ShowView { .. } = [hsx|
        <div class="mb-6 flex items-center gap-2 text-sm text-gray-500">
            <a href={DecisionRecordsAction} class="hover:text-gray-700">Decisions</a>
            <span>/</span>
            <span>{record.title}</span>
        </div>

        <div class="max-w-3xl space-y-6">
            <!-- Header card -->
            <div class="bg-white rounded-lg border border-gray-200 px-6 py-5">
                <div class="flex items-start justify-between mb-3">
                    <h1 class="text-2xl font-semibold">{record.title}</h1>
                    <div class="flex gap-2 ml-4">
                        <span class={outcomeClass record.outcome <> " text-xs px-2 py-0.5 rounded font-medium"}>
                            {record.outcome}
                        </span>
                        <a href={EditDecisionRecordAction (record.id)}
                           class="text-sm border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-50">
                            Edit
                        </a>
                    </div>
                </div>
                <div class="text-xs text-gray-400 mb-3">
                    Decided by: {userName users record.decidedBy} · {show record.decidedAt}
                </div>
                <div class="mb-3">
                    <p class="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-1">Rationale</p>
                    <p class="text-sm text-gray-700 leading-relaxed">{record.rationale}</p>
                </div>
                {maybe mempty renderNotes record.notes}
            </div>

            <!-- Linked requirement -->
            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
                <h2 class="text-sm font-semibold text-gray-700 mb-2">Linked Requirement</h2>
                {renderLinkedRequirement mRequirement}
            </div>

            <!-- Source candidate -->
            {maybe mempty renderCandidateSection mCandidate}

            <!-- Policy references -->
            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
                <h2 class="text-sm font-semibold text-gray-700 mb-3">Policy References</h2>
                {forEach policyRefs renderPolicyRef}
                <form method="POST" action={AddPolicyReferenceAction (record.id)}
                      class="mt-3 flex items-end gap-2">
                    {hiddenField "authenticity_token"}
                    <div>
                        <label class="text-xs text-gray-500 block mb-1">Scope</label>
                        <select name="policyScope"
                                class="text-sm border border-gray-300 rounded px-2 py-1.5">
                            <option value="internal">internal</option>
                            <option value="external">external</option>
                            <option value="regulatory">regulatory</option>
                            <option value="contractual">contractual</option>
                            <option value="architectural">architectural</option>
                        </select>
                    </div>
                    <div class="flex-1">
                        <label class="text-xs text-gray-500 block mb-1">Constraint note (optional)</label>
                        <input type="text" name="constraintNote"
                               class="w-full text-sm border border-gray-300 rounded px-2 py-1.5"
                               placeholder="e.g. GDPR Art. 17 right-to-erasure" />
                    </div>
                    <button type="submit"
                            class="text-sm bg-gray-100 border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-200">
                        Add
                    </button>
                </form>
            </div>

            <!-- Deployments -->
            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
                <div class="flex items-center justify-between mb-3">
                    <h2 class="text-sm font-semibold text-gray-700">Deployments</h2>
                    {if null implRefs then mempty else renderNewDeploymentLink record.id}
                </div>
                {if null deploymentRecords then noDeploymentsMsg else forEach deploymentRecords (renderDeploymentRow evaluations)}
            </div>

            <!-- Implementation references -->
            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
                <div class="flex items-center justify-between mb-3">
                    <h2 class="text-sm font-semibold text-gray-700">Implementation References</h2>
                    <form method="POST" action={ProposeImplementationAction (record.id)} class="inline">
                        <button type="submit" class="text-xs border border-green-300 text-green-700 px-2 py-1 rounded hover:bg-green-50">
                            Propose Implementation
                        </button>
                    </form>
                </div>
                {forEach implRefs renderImplRef}
                <form method="POST" action={AddImplementationRefAction (record.id)}
                      class="mt-3 flex items-end gap-2">
                    {hiddenField "authenticity_token"}
                    <div>
                        <label class="text-xs text-gray-500 block mb-1">System</label>
                        <select name="system"
                                class="text-sm border border-gray-300 rounded px-2 py-1.5">
                            <option value="github">github</option>
                            <option value="linear">linear</option>
                            <option value="jira">jira</option>
                            <option value="other">other</option>
                        </select>
                    </div>
                    <div class="flex-1">
                        <label class="text-xs text-gray-500 block mb-1">Work item ref</label>
                        <input type="text" name="workItemRef"
                               class="w-full text-sm border border-gray-300 rounded px-2 py-1.5"
                               placeholder="e.g. #1234, PROJ-456" />
                    </div>
                    <button type="submit"
                            class="text-sm bg-gray-100 border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-200">
                        Add
                    </button>
                </form>
            </div>
        </div>
    |]

renderNotes :: Text -> Html
renderNotes notes = [hsx|
    <div class="mt-2">
        <p class="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-1">Notes</p>
        <p class="text-sm text-gray-600 italic">{notes}</p>
    </div>
|]

renderCandidateSection :: RequirementCandidate -> Html
renderCandidateSection c = [hsx|
    <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
        <h2 class="text-sm font-semibold text-gray-700 mb-2">Source Candidate</h2>
        <a href={ShowRequirementCandidateAction (c.id)}
           class="text-sm text-indigo-600 hover:text-indigo-800">{c.title}</a>
    </div>
|]

renderPolicyRef :: PolicyReference -> Html
renderPolicyRef ref = [hsx|
    <div class="flex items-start justify-between py-2 border-b border-gray-100 last:border-0">
        <div class="flex items-center gap-2 text-sm">
            <span class={policyScopeClass ref.policyScope <> " text-xs px-2 py-0.5 rounded font-medium"}>
                {ref.policyScope}
            </span>
            {maybe mempty renderConstraintNote ref.constraintNote}
            <span class="text-xs text-gray-400">{show ref.createdAt}</span>
        </div>
        <form method="POST"
              action={DeletePolicyReferenceAction (ref.id)}>
            {hiddenField "authenticity_token"}
            <button type="submit"
                    class="text-xs text-red-500 hover:text-red-700 ml-2">Remove</button>
        </form>
    </div>
|]

renderImplRef :: ImplementationChangeReference -> Html
renderImplRef ref = [hsx|
    <div class="flex items-start justify-between py-2 border-b border-gray-100 last:border-0">
        <div class="flex items-center gap-2 text-sm">
            <span class={systemBadgeClass ref.system <> " text-xs px-2 py-0.5 rounded font-medium"}>
                {ref.system}
            </span>
            <span class="font-mono text-gray-700">{ref.workItemRef}</span>
            <span class="text-xs text-gray-400">{show ref.linkedAt}</span>
        </div>
        <form method="POST"
              action={DeleteImplementationRefAction (ref.id)}>
            {hiddenField "authenticity_token"}
            <button type="submit"
                    class="text-xs text-red-500 hover:text-red-700 ml-2">Remove</button>
        </form>
    </div>
|]

outcomeClass :: Text -> Text
outcomeClass "accepted"  = "bg-green-100 text-green-800"
outcomeClass "rejected"  = "bg-red-100 text-red-800"
outcomeClass "deferred"  = "bg-gray-100 text-gray-600"
outcomeClass "split"     = "bg-purple-100 text-purple-800"
outcomeClass "merged"    = "bg-indigo-100 text-indigo-800"
outcomeClass "reframed"  = "bg-orange-100 text-orange-800"
outcomeClass _           = "bg-gray-100 text-gray-600"

policyScopeClass :: Text -> Text
policyScopeClass "regulatory"   = "bg-red-50 text-red-700 border border-red-200"
policyScopeClass "contractual"  = "bg-orange-50 text-orange-700 border border-orange-200"
policyScopeClass "external"     = "bg-yellow-50 text-yellow-700 border border-yellow-200"
policyScopeClass "architectural"= "bg-blue-50 text-blue-700 border border-blue-200"
policyScopeClass _              = "bg-gray-50 text-gray-600 border border-gray-200"

systemBadgeClass :: Text -> Text
systemBadgeClass "github" = "bg-gray-800 text-white"
systemBadgeClass "linear" = "bg-violet-100 text-violet-800"
systemBadgeClass "jira"   = "bg-blue-100 text-blue-800"
systemBadgeClass _        = "bg-gray-100 text-gray-600"

renderLinkedRequirement :: Maybe Requirement -> Html
renderLinkedRequirement Nothing = [hsx|<p class="text-sm text-gray-400">No requirement linked.</p>|]
renderLinkedRequirement (Just req) = [hsx|
    <a href={ShowRequirementAction (req.id)}
       class="text-sm text-indigo-600 hover:text-indigo-800">{req.title}</a>
|]

renderNewDeploymentLink :: Id DecisionRecord -> Html
renderNewDeploymentLink recordId = [hsx|
    <a href={(pathTo NewDeploymentRecordAction) <> "?decisionId=" <> show recordId}
       class="text-xs border border-indigo-300 text-indigo-600 px-3 py-1 rounded hover:bg-indigo-50">
        New Deployment
    </a>
|]

noDeploymentsMsg :: Html
noDeploymentsMsg = [hsx|<p class="text-sm text-gray-400">No deployments recorded yet.</p>|]

renderConstraintNote :: Text -> Html
renderConstraintNote n = [hsx|<span class="text-gray-600">{n}</span>|]

renderDeploymentRow :: [ChangeEvaluation] -> DeploymentRecord -> Html
renderDeploymentRow evals dr = [hsx|
    <div class="flex items-center justify-between py-2 border-b border-gray-100 last:border-0">
        <div class="flex items-center gap-2 text-sm">
            <a href={ShowDeploymentRecordAction (dr.id)}
               class="font-mono text-indigo-600 hover:text-indigo-800">{dr.versionRef}</a>
            <span class="text-xs text-gray-400">{show dr.deployedAt}</span>
        </div>
        {maybe mempty renderEvalSummary mEval}
    </div>
|]
  where
    mEval = find (\e -> e.deploymentId == dr.id) evals

renderEvalSummary :: ChangeEvaluation -> Html
renderEvalSummary ev = [hsx|
    <span class={scoreClass ev.score <> " text-xs px-2 py-0.5 rounded font-medium"}>
        {starsFor ev.score}
    </span>
|]

starsFor :: Int16 -> Text
starsFor n = pack (Prelude.replicate (fromIntegral n) '★') <> pack (Prelude.replicate (5 - fromIntegral n) '☆')

scoreClass :: Int16 -> Text
scoreClass n
    | n <= 2    = "bg-red-100 text-red-800"
    | n == 3    = "bg-yellow-100 text-yellow-800"
    | otherwise = "bg-green-100 text-green-800"

userName :: [User] -> Maybe (Id User) -> Text
userName _     Nothing    = "—"
userName users (Just uid) = maybe "(unknown)" (.name) (find (\u -> u.id == uid) users)