// runHooks — generic per-environment CI/CD hook runner (execution core).
//
// Executes user-provided scripts (shell or python) that live in the service
// repo and are declared under `environment.<env>.hooks.<phase>` in the repo's
// config.yaml. The platform stays generic: it only locates, contextualises
// (via TT_* env vars) and runs each script — all use-case logic lives in the
// script itself.
//
// Build-phase entry (call from commonCICDFlow, repo already checked out):
//   runHooks(param, 'pre_build')   // before docker build
//   runHooks(param, 'post_build')  // after a successful build
//
// Deploy-phase re-use (from cdHookRunner, after it checks out the repo):
//   runHooks.executeHooks(repoName, hooks, phase, ctxEnv)
//
// By the time the build-phase entry runs, constructParam has merged the
// resolved environment block into `param` top-level, so the current env's hooks
// are at `param.hooks`. The repo is checked out into `${repoName}`, so scripts
// run with CWD at the repo root and can reach any repo file.
def call(Map param, String phase) {
    def hooksBlock = param?.hooks
    if (!(hooksBlock instanceof Map)) {
        return
    }
    def hooks = hooksBlock[phase]
    if (!(hooks instanceof List) || hooks.isEmpty()) {
        return
    }

    String repoName = param?.repo_name
    if (!repoName) {
        error("runHooks: param.repo_name is missing — cannot locate hook scripts.")
    }

    executeHooks(repoName, hooks, phase, buildPhaseContextEnv(repoName, phase))
}

// executeHooks runs each hook spec in `hooks` inside the repo working directory,
// injecting `ctxEnv` (the TT_* context contract) plus a per-hook TT_HOOK_NAME.
// Reused by both the build-phase entry and the deploy-phase cdHookRunner.
def executeHooks(String repoName, def hooks, String phase, List<String> ctxEnv) {
    hooks.eachWithIndex { hook, idx ->
        runOneHook(repoName, phase, idx, hook, ctxEnv)
    }
}

// runOneHook executes a single hook spec inside the repo working directory.
def runOneHook(String repoName, String phase, int idx, def hook, List<String> ctxEnv) {
    String name = (hook?.name ?: "${phase}-${idx}").toString()
    String script = hook?.script?.toString()
    String interpreter = hook?.interpreter?.toString()
    String requirements = hook?.requirements?.toString()
    // Blocking by default; only an explicit `blocking: false` demotes to advisory.
    boolean blocking = !(hook?.blocking?.toString() == 'false')
    int timeoutSeconds = 600
    if (hook?.timeout_seconds) {
        try { timeoutSeconds = hook.timeout_seconds.toString().toInteger() } catch (ignored) { timeoutSeconds = 600 }
    }

    if (!script) {
        error("runHooks: ${phase}[${idx}] '${name}' has no 'script' path in config.yaml.")
    }
    assertRepoRelative(script, "${phase}[${idx}] '${name}' script")
    if (requirements) {
        assertRepoRelative(requirements, "${phase}[${idx}] '${name}' requirements")
    }

    stage(stageName("${phase}: ${name}")) {
        dir(repoName) {
            if (!fileExists(script)) {
                error("runHooks: ${phase} hook '${name}' script not found in repo: ${script}")
            }

            List<String> hookEnv = []
            hookEnv.addAll(ctxEnv)
            hookEnv.add("TT_HOOK_PHASE=${phase}")
            hookEnv.add("TT_HOOK_NAME=${name}")
            String runCmd = buildRunCommand(script, interpreter, requirements)

            log.info("runHooks: executing ${phase} hook '${name}' (${script}), blocking=${blocking}, timeout=${timeoutSeconds}s")
            withEnv(hookEnv) {
                try {
                    timeout(time: timeoutSeconds, unit: 'SECONDS') {
                        sh(script: runCmd)
                    }
                } catch (Exception e) {
                    if (blocking) {
                        log.error("runHooks: blocking ${phase} hook '${name}' failed: ${e}")
                        throw e
                    }
                    // Advisory hook — record and continue without failing the build.
                    log.warning("runHooks: advisory ${phase} hook '${name}' failed (non-blocking): ${e}")
                    currentBuild.description = (currentBuild.description ? currentBuild.description + " | " : "") + "hook(${name}) advisory-failed"
                }
            }
        }
    }
}

// buildRunCommand resolves the interpreter (explicit > extension > shebang) and,
// when a python requirements file is given, provisions an ephemeral venv.
def buildRunCommand(String script, String interpreter, String requirements) {
    String interp = interpreter
    if (!interp) {
        if (script.endsWith('.py')) {
            interp = 'python3'
        } else if (script.endsWith('.sh')) {
            interp = 'bash'
        }
    }

    boolean isPython = (interp == 'python3' || interp == 'python' || script.endsWith('.py'))
    if (requirements && isPython) {
        String py = interp ?: 'python3'
        return """
            set -e
            ${py} -m venv .tt_hook_venv
            . .tt_hook_venv/bin/activate
            pip install --quiet --disable-pip-version-check -r ${requirements}
            ${py} ${script}
        """.stripIndent().trim()
    }

    if (interp) {
        return "set -e\n${interp} ${script}"
    }
    // No interpreter resolved — rely on the script's shebang.
    return "set -e\nchmod +x ${script}\n./${script}"
}

// buildPhaseContextEnv builds the standard TT_* env-var contract for build-phase
// hooks from the pipeline env already populated by constructParam / the GitHub
// Branch Source plugin.
def buildPhaseContextEnv(String repoName, String phase) {
    boolean isPR = (env.CHANGE_ID ? true : false)
    String branch = isPR ? (env.CHANGE_BRANCH ?: env.BRANCH_NAME ?: '') : (env.BRANCH_NAME ?: '')
    boolean isHotfix = (env.hot_fix == 'true' || env.hot_fix == true)
    return [
        "TT_REPO_NAME=${repoName}",
        "TT_ENV=${env.cicd_environment ?: ''}",
        "TT_EVENT=${isPR ? 'pr' : 'push'}",
        "TT_IS_HOTFIX=${isHotfix}",
        "TT_BRANCH=${branch}",
        "TT_TARGET_BRANCH=${env.CHANGE_TARGET ?: ''}",
        "TT_PR_NUMBER=${env.CHANGE_ID ?: ''}",
        "TT_COMMIT_SHA=${env.GIT_COMMIT ?: ''}",
        "TT_IMAGE_TAG=${env.image_tag ?: ''}",
    ]
}

// assertRepoRelative rejects absolute paths and parent-directory traversal so a
// hook can only execute code that lives inside the checked-out repo.
def assertRepoRelative(String p, String what) {
    if (p.startsWith('/')) {
        error("runHooks: ${what} path '${p}' must be repo-relative, not absolute.")
    }
    if (p == '..' || p.startsWith('../') || p.contains('/../')) {
        error("runHooks: ${what} path '${p}' must not traverse outside the repo ('..').")
    }
}