package webui

import (
	"fmt"
	"html"
	"net/http"
	"os"
	"strings"
)

func (h *handler) handleTaskPage(w http.ResponseWriter, r *http.Request) {
	id := r.PathValue("id")
	task, ok := globalQueue.findByID(id)
	if !ok {
		http.NotFound(w, r)
		return
	}
	snapshot := *task
	body := renderTaskDetailPage(h.opts, snapshot)
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	_, _ = w.Write([]byte(body))
}

func renderTaskDetailPage(opts HandlerOptions, task Task) string {
	title := task.Name
	if strings.TrimSpace(title) == "" {
		title = task.ID
	}
	var body strings.Builder
	body.WriteString(`<div style="display:flex;align-items:center;gap:12px;margin-bottom:16px;flex-wrap:wrap">`)
	body.WriteString(`<a class="btn btn-secondary btn-sm" href="/tasks">Back to Tasks</a>`)
	body.WriteString(`<span style="font-size:12px;color:var(--muted)">Artifacts are saved in the task folder under <code>./tasks</code>.</span>`)
	body.WriteString(`</div>`)

	if report := loadTaskReportFragment(task); report != "" {
		body.WriteString(report)
	} else {
		body.WriteString(`<div class="card"><div class="card-head">Task Summary</div><div class="card-body">`)
		body.WriteString(`<div style="font-size:18px;font-weight:700">` + html.EscapeString(title) + `</div>`)
		body.WriteString(`<div style="margin-top:8px">` + renderTaskStatusBadge(task.Status) + `</div>`)
		if strings.TrimSpace(task.ErrMsg) != "" {
			body.WriteString(`<div style="margin-top:8px;color:var(--crit-fg)">` + html.EscapeString(task.ErrMsg) + `</div>`)
		}
		body.WriteString(`</div></div>`)
	}

	if task.Status == TaskRunning || task.Status == TaskPending {
		body.WriteString(`<div class="card"><div class="card-head">Live Logs</div><div class="card-body">`)
		body.WriteString(`<div id="task-live-log" class="terminal" style="max-height:none;white-space:pre-wrap">Connecting...</div>`)
		body.WriteString(`</div></div>`)
		body.WriteString(`<script>
var _taskDetailES = new EventSource('/api/tasks/` + html.EscapeString(task.ID) + `/stream');
var _taskDetailTerm = document.getElementById('task-live-log');
_taskDetailES.onopen = function(){ _taskDetailTerm.textContent = ''; };
_taskDetailES.onmessage = function(e){ _taskDetailTerm.textContent += e.data + "\n"; _taskDetailTerm.scrollTop = _taskDetailTerm.scrollHeight; };
_taskDetailES.addEventListener('done', function(){ _taskDetailES.close(); setTimeout(function(){ window.location.reload(); }, 1000); });
_taskDetailES.onerror = function(){ _taskDetailES.close(); };
</script>`)
	}

	return layoutHead(opts.Title+" — "+title) +
		layoutNav("tasks", opts.BuildLabel) +
		`<div class="main"><div class="topbar"><h1>` + html.EscapeString(title) + `</h1></div><div class="content">` +
		body.String() +
		`</div></div></body></html>`
}

func loadTaskReportFragment(task Task) string {
	if strings.TrimSpace(task.ReportHTMLPath) == "" {
		return ""
	}
	data, err := os.ReadFile(task.ReportHTMLPath)
	if err != nil || len(data) == 0 {
		return ""
	}
	return string(data)
}

func taskArtifactDownloadLink(task Task, absPath string) string {
	if strings.TrimSpace(absPath) == "" {
		return ""
	}
	return fmt.Sprintf(`/export/file?path=%s`, absPath)
}