name: Discord — Release Merge Notification

on:
  pull_request:
    types:
      - closed
    branches:
      - release

jobs:
  notify:
    # Solo cuando el PR fue efectivamente mergeado (no cerrado sin merge)
    if: github.event.pull_request.merged == true
    runs-on: ubuntu-latest
    permissions:
      contents: write   # necesario para pushear CHANGELOG.md

    steps:
      - name: Checkout full history
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          token: ${{ secrets.GITHUB_TOKEN }}
          ref: release

      - name: Configure git identity
        run: |
          git config user.name  "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

      - name: Generate CHANGELOG entry, commit, then send Discord announcement
        uses: actions/github-script@v7
        env:
          DAVEAGENT_API_KEY:   ${{ secrets.DAVEAGENT_API_KEY }}
          DISCORD_BOT_TOKEN:   ${{ secrets.DISCORD_BOT_TOKEN }}
          DISCORD_CHANNEL_ID:  ${{ secrets.DISCORD_CHANNEL_ID }}
        with:
          script: |
            const { execSync } = require('child_process');
            const fs = require('fs');
            const today = new Date().toISOString().slice(0, 10);

            // ── Helpers ──────────────────────────────────────────────────────
            function git(cmd) {
              try {
                return execSync(`git ${cmd}`, { encoding: 'utf8', stdio: ['pipe', 'pipe', 'pipe'] }).trim();
              } catch { return ''; }
            }

            async function callDeepSeek(prompt, maxTokens = 800, temperature = 0.3) {
              const apiKey = process.env.DAVEAGENT_API_KEY;
              if (!apiKey) throw new Error('DAVEAGENT_API_KEY not set');
              const res = await fetch('https://api.deepseek.com/v1/chat/completions', {
                method: 'POST',
                headers: {
                  'Content-Type': 'application/json',
                  'Authorization': `Bearer ${apiKey}`,
                },
                body: JSON.stringify({
                  model: 'deepseek-chat',
                  max_tokens: maxTokens,
                  temperature,
                  messages: [{ role: 'user', content: prompt }],
                }),
              });
              if (!res.ok) {
                const err = await res.text();
                throw new Error(`DeepSeek ${res.status}: ${err}`);
              }
              const data = await res.json();
              return (data.choices?.[0]?.message?.content ?? '').trim();
            }

            // ── Version ──────────────────────────────────────────────────────
            // The version to announce comes from frontend/package.json on the
            // release branch. After announcing we bump the PATCH and commit it
            // back to release, so EACH merge announces a fresh version
            // (3.0.0 -> 3.0.1 -> 3.0.2 ...) instead of repeating the same one.
            // To jump the major/minor, edit frontend/package.json on the
            // release branch (e.g. set "version": "3.1.0") and the next merge
            // continues from there.
            let version = '3.0.0';
            try {
              const pkg = JSON.parse(fs.readFileSync('frontend/package.json', 'utf8'));
              version = pkg.version ?? '3.0.0';
            } catch {}

            function bumpPatch(v) {
              const m = String(v).match(/^(\d+)\.(\d+)\.(\d+)/);
              if (!m) return v;            // leave non-semver strings untouched
              return `${m[1]}.${m[2]}.${Number(m[3]) + 1}`;
            }
            const nextVersion = bumpPatch(version);
            console.log(`Version: v${version}  ->  next: v${nextVersion}`);

            // ── Rango exacto del PR mergeado ──────────────────────────────────
            // base.sha = tip de release ANTES del merge
            // head.sha = tip de la rama fuente (master u otra)
            const pr = context.payload.pull_request;
            const baseSha    = pr.base.sha;
            const headSha    = pr.head.sha;
            const sourceBranch = pr.head.ref;        // ej: "master"
            const prTitle    = pr.title ?? '';
            const prBody     = pr.body  ?? '';

            console.log(`PR: #${pr.number} "${prTitle}"`);
            console.log(`Range: ${baseSha.slice(0,7)}..${headSha.slice(0,7)} (${sourceBranch} → release)`);

            // Commits que entraron (con hash + subject + body + autor)
            const commits = git(
              `log ${baseSha}..${headSha} --pretty=format:"%h||%s||%b||%an|||" --no-merges`
            ) || git(`log -30 --pretty=format:"%h||%s||%b||%an|||" --no-merges`);

            // Lineas simples para el anuncio Discord
            const commitLines = git(
              `log ${baseSha}..${headSha} --pretty=format:"%h %s" --no-merges`
            ) || git(`log -20 --pretty=format:"%h %s" --no-merges`);

            const changedFiles = git(`diff --name-only ${baseSha}..${headSha}`)
              .split('\n').filter(Boolean);

            console.log(`Commits found: ${commitLines.split('\n').filter(Boolean).length}`);
            console.log(`Files changed: ${changedFiles.length}`);

            // ──────────────────────────────────────────────────────────────────
            // FASE 1 — Generar entrada de CHANGELOG con DeepSeek
            // ──────────────────────────────────────────────────────────────────
            const changelogPrompt = `You are generating a CHANGELOG entry for version ${version} of Velxio.

            Velxio is a fully local, open-source Arduino/RP2040 emulator and circuit simulator.

            PR TITLE: ${prTitle}
            PR DESCRIPTION: ${prBody}
            SOURCE BRANCH: ${sourceBranch}

            GIT COMMITS (hash||subject||body||author):
            ${commits}

            Generate a changelog entry using EXACTLY this format:

            ## [${version}] - ${today}

            ### Added
            - New user-facing features

            ### Changed
            - Changes in existing functionality

            ### Fixed
            - Bug fixes

            RULES:
            1. Group commits by category (Added, Changed, Fixed, Performance, Removed, Security)
            2. Write in past tense, user-facing language
            3. Skip trivial commits (formatting, typos, version bumps)
            4. Combine related commits into single entries
            5. Remove commit hashes and author names
            6. Only include sections that have real content
            7. Output ONLY the changelog entry block, nothing else`;

            console.log('Generating CHANGELOG entry...');
            const changelogEntry = await callDeepSeek(changelogPrompt, 800, 0.3);

            // ── Actualizar CHANGELOG.md ───────────────────────────────────────
            const changelogPath = 'CHANGELOG.md';
            let changelogContent;

            if (!fs.existsSync(changelogPath)) {
              changelogContent = '# Changelog\n\n'
                + 'All notable changes to Velxio will be documented in this file.\n'
                + 'The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).\n\n'
                + changelogEntry + '\n\n'
                + `[${version}]: https://github.com/davidmonterocrespo24/velxio/releases/tag/v${version}\n`;
            } else {
              const existing = fs.readFileSync(changelogPath, 'utf8');
              const lines = existing.split('\n');

              // Insertar antes del primer ## [ o despues del header
              let insertIdx = lines.findIndex(l => l.startsWith('## ['));
              if (insertIdx === -1) {
                insertIdx = lines.findIndex((l, i) => i > 3 && l.trim() === '') + 1;
              }

              lines.splice(insertIdx, 0, changelogEntry, '');

              const linkLine = `[${version}]: https://github.com/davidmonterocrespo24/velxio/releases/tag/v${version}`;
              if (!existing.includes(linkLine)) lines.push(linkLine);

              changelogContent = lines.join('\n');
            }

            fs.writeFileSync(changelogPath, changelogContent, 'utf8');
            console.log('CHANGELOG.md updated');

            // ── Bump frontend/package.json to the next patch ──────────────────
            // This is the fix for the "same version announced every time" bug:
            // nothing ever advanced the counter. Text-replace so the file's
            // existing formatting is preserved.
            try {
              const pkgPath = 'frontend/package.json';
              const pkgRaw = fs.readFileSync(pkgPath, 'utf8');
              const bumped = pkgRaw.replace(
                /("version"\s*:\s*")[^"]+(")/,
                `$1${nextVersion}$2`
              );
              fs.writeFileSync(pkgPath, bumped, 'utf8');
              console.log(`Bumped frontend/package.json: ${version} -> ${nextVersion}`);
            } catch (e) {
              console.log('package.json bump failed:', e.message);
            }

            // ── Commit y push del CHANGELOG + version bump ────────────────────
            try {
              execSync('git add CHANGELOG.md frontend/package.json', { stdio: 'inherit' });
              execSync(
                `git commit -m "chore: release v${version}, bump to v${nextVersion} [skip ci]"`,
                { stdio: 'inherit' }
              );
              execSync('git push origin release', { stdio: 'inherit' });
              console.log(`CHANGELOG + version bump committed and pushed (next: v${nextVersion})`);
            } catch (e) {
              console.log('Nothing to commit or push failed:', e.message);
            }

            // ──────────────────────────────────────────────────────────────────
            // FASE 2 — Generar anuncio Discord usando el CHANGELOG recien generado
            // ──────────────────────────────────────────────────────────────────
            const announcementPrompt = `You are writing a Discord announcement for Velxio v${version}.

            Velxio is a fully local, open-source Arduino/RP2040 emulator and circuit simulator that runs in the browser.
            Website: https://velxio.dev/
            GitHub: https://github.com/davidmonterocrespo24/velxio

            CRITICAL: The announcement MUST be 1900 characters or less.

            CHANGELOG for this version (use this as the source of truth):
            ${changelogEntry}

            RECENT COMMITS (for additional context):
            ${commitLines}

            STYLE EXAMPLES:

            EXAMPLE 1:
            v2.0.0 @everyone

            Velxio just got a major upgrade. Here is what is new.

            GROUND CHECK FOR LEDS
            LEDs now require a proper cathode connection to GND. No more phantom lights without a complete circuit.

            GENERIC OUTPUT COMPONENT PROTECTION
            Any output component connected without a ground wire stays off. The simulator now enforces real circuit behavior for all components.

            SSD1306 SPI MODE
            The SSD1306 OLED display now supports both I2C and SPI. Switch protocols from the component property dialog.

            Try it now: https://velxio.dev/
            Full release details: https://github.com/davidmonterocrespo24/velxio/releases/tag/v2.0.0

            EXAMPLE 2:
            v2.0.1 @everyone

            Quick fixes in this update:

            Fixed LED staying on after simulation stops
            Fixed wire color not persisting on reload
            Fixed serial monitor scroll position resetting mid-output

            Update your Docker image or open https://velxio.dev/

            STYLE RULES:
            - Start with version number and @everyone on the first line
            - No emojis
            - No markdown (no **, no ###)
            - Use ALL CAPS for section headers when grouping multiple features
            - Focus on USER BENEFITS, not implementation details
            - Under 1900 characters
            - End with link to GitHub release
            - Write in English`;

            console.log('Generating Discord announcement...');
            let announcement = await callDeepSeek(announcementPrompt, 600, 0.7);

            // Limpiar markdown residual
            announcement = announcement
              .replace(/###/g, '')
              .replace(/\*\*/g, '')
              .replace(/__/g, '')
              .trim();

            // Truncar si excede el limite
            if (announcement.length > 1900) {
              const cut = announcement.lastIndexOf('\n', 1900);
              announcement = announcement.slice(0, cut > 1200 ? cut : 1900).trim();
            }

            console.log('='.repeat(70));
            console.log('DISCORD ANNOUNCEMENT:');
            console.log('='.repeat(70));
            console.log(announcement);
            console.log(`\nCharacters: ${announcement.length}/1900`);

            // ──────────────────────────────────────────────────────────────────
            // FASE 3 — Enviar a Discord via Bot API
            // ──────────────────────────────────────────────────────────────────
            const botToken  = process.env.DISCORD_BOT_TOKEN;
            const channelId = process.env.DISCORD_CHANNEL_ID;
            if (!botToken || !channelId) {
              core.setFailed('DISCORD_BOT_TOKEN or DISCORD_CHANNEL_ID secret not configured');
              return;
            }

            const discordRes = await fetch(
              `https://discord.com/api/v10/channels/${channelId}/messages`,
              {
                method: 'POST',
                headers: {
                  'Content-Type':  'application/json',
                  'Authorization': `Bot ${botToken}`,
                },
                body: JSON.stringify({ content: announcement }),
              }
            );

            if (!discordRes.ok) {
              const err = await discordRes.text();
              core.setFailed(`Discord ${discordRes.status}: ${err}`);
              return;
            }

            console.log('='.repeat(70));
            console.log(`Release v${version} announced on Discord`);
            console.log(`PR #${pr.number} | Commits: ${commitLines.split('\n').filter(Boolean).length} | Files: ${changedFiles.length}`);